bluuebunny/crossref_metadata_2025 huggingface dataset:
Factors associated with late hospital arrival in acute stroke patients of Bangladesh
Authors: Iktidar Mohammad Azmain , Manna Ridwana Maher , Akhter Muntasrina , Roy Simanta , Bonna Atia Sharmin , Chowdhury Sreshtha , Yousuf Renessa , Mimi Farzana Ahammad , Sayed MD Samee U , Haque Miah MD Akiful , Hawlader Mohammad Delwer Hossain
Published: December 2024

Objectives

Underutilisation of thrombolysis is a major problem in patients with stroke in Bangladesh as patients do not arrive within the therapeutic window due to delays in their way to emergency department. This study aims to assess the time delay from patients’ symptom onset to arrival in the hospital and the factors that are associated with it.

Methods

This cross-sectional survey of a prospective cohort of stroke patients was conducted between January and March 2023. 448 stroke patients meeting the inclusion criteria were enrolled in the study from five tertiary-level hospitals in Bangladesh. After obtaining informed consent, trained data collectors conducted face-to-face interviews of the patient/patients’ guardians via a pretested structured questionnaire. Stata (V.16) was used to analyse data. Median and IQRs were used to summarise quantitative variables, and qualitative variables were summarised using frequency and relative frequency. Pearson’s χ2test and Mann-Whitney U test were used to explore the bivariate relationship between predictor and outcome variables. Finally, a binary logistic regression model was fit to explore the factors associated with delayed arrival (>4.5 hours) at the hospital.

Results

The median age of the patients was 61 years (54–70) and 63% were men. The majority hailed from rural (59.6%) areas and had primary (25.89%) education. The patients had an overall median prehospital delay of 14 (8–28) hours, 3 (1–6) hours of decision delay, 1 (0–2) hours of medical contact delay, and 14 (6.5–25.75) hours of referral delay. Patients with master’s education (adjusted OR (AOR): 0.04, p=0.023) and private transport (AOR: 0.26, p=0.029) had a lower chance of late arrival. However, patients having unknown onset, self-medicating, having a previous history of stroke, and being admitted to a private hospital had a significantly higher chance of late arrival.

Conclusion

Nearly 90% of the patients were late to arrive (>4.5 hours) at hospital and referral delay comprises the majority of the prehospital delay. Therefore, fast symptom recognition and the urgency of seeking healthcare as soon as symptoms appear should be the focus of public awareness efforts.
Validation of the NCCN/Yale criteria for the identification ofCDH1pathogenic variant carriers
Authors: Lerner Benjamin A , Giner-Calabuig Mar , Carraway Cassidy , Richardson Marcy , Krahn Karl , Susswein Lisa , Nielsen Sarah M , Karam Rachid , Xicola Rosa M , Llor Xavier
Published: December 2024

Background

Diffuse gastric and lobular breast cancer (LBC) syndrome is an autosomal-dominant syndrome characterised by early-onset diffuse gastric cancer and LBC most often caused by germline pathogenic variants (PVs) inCDH1. We previously showed the International Gastric Cancer Linkage Consortium (IGCLC) criteria for genetic testing to have poor sensitivity forCDH1PV and proposed our own simpler and more sensitive Yale criteria. The European Reference Network on Genetic Tumour Risk Syndromes subsequently proposed expanding the IGCLC criteria and showed its LBC-expanded criteria to be more sensitive than the IGCLC criteria in a European cohort ofCDH1PV carriers.

Methods

We aggregated demographic and clinical data of allCDH1PV carriers identified at three US commercial laboratories. These data were used to calculate the sensitivity of the IGCLC, LBC-expanded and National Comprehensive Cancer Network (NCCN)/Yale criteria.

Results

Data on 708 probands and their 4318 family members were included in the analysis. In this cohort, the sensitivities for detectingCDH1PVs were 23.6% for IGCLC criteria, 35.7% for LBC-expanded criteria and 82.2% for NCCN/Yale criteria.

Conclusion

In a large cohort ofCDH1PV carriers to date, the IGCLC and LBC-expanded criteria called for genetic testing in a minority ofCDH1PV carriers while the Yale criteria detected the large majority. Along with their superior sensitivity, the NCCN/Yale criteria address critical practical challenges in cancer genetics by not depending heavily on pathology information from family members which is often lacking and by incorporating recommendations from other cancer genetics guidelines.
Healthcare workers’ well-being and perspectives on support during the COVID-19 pandemic: a systematic review and meta-synthesis of qualitative studies
Authors: Zhang Siyuan , Gu Xiuzhu
Published: December 2024

Background

Since the outbreak of the COVID-19 pandemic, healthcare workers (HCWs) have faced multiple difficulties in their work and personal lives. However, most of the quantitative reviews have focused on the extent of the pandemic’s impact on the HCWs and have thus failed to fully capture the HCWs’ experiences and the complexity of the problems they encountered. Therefore, this qualitative systematic review elucidates the HCWs’ challenges brought about by the pandemic, their perceptions of the existing support and the support that require further attention.

Methods

The literature search spanned five databases: Scopus, PubMed, Web of Science, CINAHL and PsycInfo, targeting qualitative studies of HCWs’ pandemic experiences from December 2019 to December 2023. These studies underwent strict quality and relevance assessment, emphasising critical appraisal and selection. Findings were unified through meta-synthesis, adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The study was registered in PROSPERO.

Results

This study analysed 29 qualitative studies on HCWs’ experiences during the pandemic and their perceptions of support, identifying four themes of HCWs’ physical and mental well-being, the impact of the pandemic on their professional and personal lives, their work environments and the support they received. These themes encompassed 8 main categories and 25 codes. The research revealed that the pandemic and work conditions negatively influenced their health, affecting their professional and personal lives. Current support has lessened the pandemic’s effects on HCWs but should also address future requirements like long-term psychological support.

Conclusion

The studies identified the challenges faced by HCWs during the pandemic, and the existing support. However, due to the complex interactions between the work and environmental factors, the effectiveness of the existing support remains challenging. To improve their effectiveness, the future support should target the interactions between the HCWs and the work system.

PROSPERO registration number

CRD42023426238.
New benzo-9-crown-3 functionalized aryl imides for the capture and release of lithium ions from solution
Authors: Atkinson Colton , Welch Gregory C.
Published: December 2024

With an increased demand for lithium ion (Li-ion) battery technologies, and the small number of lithium mines around the globe, there has been a heightened desire to develop new materials capable of extracting lithium from aqueous sources such as the ocean. To do so in an economically viable way, the materials must be highly selective toward the extraction of Li-ions so as not to necessitate the further purification from competing metal ions such as magnesium, sodium, or calcium. To address this, herein we report on three new conjugated imide compounds functionalized with the crown ether benzo-9-crown-3. The three new compounds Phth-CE, F-Phth-CE, and NMI-CE were synthesized via atom-economical condensation reactions between an amino functionalized benzo-9-crown-3 with commodity aryl imide building blocks. These three new compounds serve to develop an understanding of Li-ion capture via the benzo-9-crown-3 moieties scaffolded onto stable aromatic ring systems. The nodal plane between the aryl imide and the phenyl ring of benzo-9-crown-3 isolates the crown ether allowing for unhindered Li-ion capture and release. Subtle derivatization of the aryl imide showcases structural versatility to include a fluoride amenable to nucleophilic aromatic substitution and/or to act as a diagnostic handle and naphthalene unit extending optical absorption to longer wavelengths. Each new compound exhibits the formation of Li-ion sandwich complexes as determined by 7Li NMR spectroscopy, and near identical Li-ion extraction efficiencies, distribution coefficients, and selectivity under acidic conditions in neat and mixed-metal ion solutions as determined by triple quadrupole inductively coupled plasma mass spectrometry analysis.
Binary logistic regression model for pavement marking retroreflectivity of Wyoming highways
Authors: Tajnin Mst Rahanuma , Roy Uttara , Ksaibati Khaled
Published: December 2024

This study focuses on the factors affecting the retroreflectivity ( RL) of longitudinal pavement marking using the data collected from four different functional classes of roads in Wyoming. Two different approaches were considered: the whole dataset was used in one approach, while in another, the dataset was classified based on functional classification. In both approaches, a binary logistic regression model was developed to investigate the factors affecting the probability of RL above the WYDOT’s marginal retroreflectivity level (125 and 100 mcd/m2/lux for white and yellow marking, respectively). A total of six categorical variables and eight continuous variables were incorporated into the models. The marking age, color, material, line type, highway location, and degree of curvature impact the pavement marking retroreflectivity above the marginal level. Regarding the horizontal curve, the increase in the degree of curvature of the horizontal curve decreases the likelihood of having the RL exceeding the marginal level.
Classifying southern stingray activity states across abiotic factors in Belize coral reef ecosystems
Authors: Flowers Kathryn I. , Babcock Elizabeth A. , Chapman Demian D. , Lamb Norlan , Miranda Ashbert , Nuñez Randolph , Kelley Megan C. , Papastamatiou Yannis P.
Published: December 2024

Elasmobranchs often exhibit nocturnal or crepuscular activity, with shark diel patterns being better understood than ray diel patterns. We used accelerometry and hidden Markov models (HMMs) to classify female southern stingray ( Hypanus americanus Hildebrand & Schroeder, 1928) activity states across diel periods and environmental conditions in Belize. Three state (low, medium, and high activity) HMMs were constructed for all individuals together and separately ( N = 9). Combined, stingrays were most likely to be highly active at night and in low and medium activity states in the morning. However, there was individual variation in diel activity. In contrast, all stingrays consistently used shallow water (<4 m) during periods of high activity. Temperature had less influence on activity patterns, although three individuals exhibited high activity in cooler water. Generally, high stingray activity was driven by diel cycles and depth. Future research should link activity states to specific behaviours, include a larger sample size, extend tag deployment durations, and explore the impact of predator and prey dynamics on stingray activity.
Autism Spectrum Disorder Detection Using Prominent Connectivity Features from Electroencephalography
Authors: Peya Zahrul Jannat , Maria Mahfuza Akter , Hossain Sk Imran , Akhand M. A. H. , Siddique Nazmul
Published: December 2024

Autism Spectrum Disorder (ASD) is a disorder of brain growth with great variability whose clinical presentation initially shows up during early stages or youth, and ASD follows a repetitive pattern of behavior in most cases. Accurate diagnosis of ASD has been difficult in clinical practice as there is currently no valid indicator of ASD. Since ASD is regarded as a neurodevelopmental disorder, brain signals specially electroencephalography (EEG) are an effective method for detecting ASD. Therefore, this research aims at developing a method of extracting features from EEG signal for discriminating between ASD and control subjects. This study applies six prominent connectivity features, namely Cross Correlation (XCOR), Phase Locking Value (PLV), Pearson’s Correlation Coefficient (PCC), Mutual Information (MI), Normalized Mutual Information (NMI) and Transfer Entropy (TE), for feature extraction. The Connectivity Feature Maps (CFMs) are constructed and used for classification through Convolutional Neural Network (CNN). As CFMs contain spatial information, they are able to distinguish ASD and control subjects better than other features. Rigorous experimentation has been performed on the EEG datasets collected from Italy and Saudi Arabia according to different criteria. MI feature shows the best result for categorizing ASD and control participants with increased sample size and segmentation.
New correlations for determining nonuniform liquid film thickness and interfacial friction in two-phase flow within a vertically inclined pipe
Authors: Ghafouri Arash , Ghafouri Ashkan , Kosarineia Abbas , Daneh-Dezfuli Alireza
Published: December 2024

Two-phase flow in inclined pipes frequently occurs in industrial applications such as oil and gas production, heat exchangers and nuclear reactors. Understanding liquid film thickness and interfacial friction coefficient is crucial for designing and optimizing these systems. This study investigates the effect of limited inclination angles on liquid film thickness and interfacial friction coefficient in two-phase flow within vertical pipes. An image recording and processing technique analyzes the counter-current flow of water and air, which forms an annular flow pattern in transparent pipes of various sizes. The results are segregated based on superficial velocities, Reynolds numbers and pipe diameters. A multivariate correlation is developed to determine the ratio of maximum to minimum film thickness and an equivalent film thickness correlation for inclined pipes. The interfacial friction coefficient is also evaluated, leading to a tri-variable correlation. The proposed correlations align closely with presented data and prior research ([Formula: see text] for film thickness ratio and [Formula: see text] for interfacial friction coefficient). The maximum deviation between data and proposed correlations is 2.86% for film thickness and 4.3% for the interfacial friction coefficient. These findings enhance the understanding of two-phase flow behavior in inclined pipes and offer valuable tools for industrial design and optimization.
ARE THERE TIME-VARYING CAUSALITIES BETWEEN TRADE POLICY UNCERTAINTY AND CARBON EMISSION TRANSFER? NEW EVIDENCE FROM CHINA
Authors: WANG KAI-HUA , LI MIAO , GE FENGNING
Published: December 2024

In this paper, we examine the relationship between Chinese carbon emission transfer and trade policy uncertainty. We identify the evidence of bidirectional Granger causality using the bootstrap rolling-window approach, and further test the influence mechanism using a logit model. Empirical results spanning different sub-samples reveal a two-way causal relationship between trade policy uncertainty and carbon emission transfer. Trade policy uncertainty will reduce carbon emission transfer indirectly by limiting international trade and foreign direct investment. Whereas trade policy uncertainty will boost carbon emission transfer by increasing technological innovation hurdles. Conversely, carbon emission transfer exacerbates trade policy uncertainty through strategic environmental policies and carbon tariffs. This discovery broadens the research on trade policy uncertainty to environmental concerns, and time-varying causation expands the impact path of carbon emission transfer while clarifying global carbon emission responsibility. The findings recommend a responsible trading strategy based on environmental considerations and international cooperation to limit carbon transfer.
On pseudo-conjugation actions of finite groups and related topics
Authors: Almeida T. L. B. , Moghaddamfar A. R. , Nakaoka I. N.
Published: December 2024

In this paper, we introduce the concept of a pseudo-conjugation action of a group [Formula: see text] on itself. This action behaves like conjugation. The purpose of this paper is twofold. First, it provides several useful properties of pseudo-conjugation actions that should simplify other calculations. Second, it extends specific concepts of group theory, such as AC-groups and the notion of isoclinism between two groups, among others. A connection between a pseudo-conjugation action and the conjugation action is also examined.
Chirally cosmetic surgeries on Kinoshita–Terasaka and Conway knot families
Authors: Yang Xiliu
Published: December 2024

In this note, we prove that a nontrivial Kinoshita–Terasaka or Conway knot does not admit chirally cosmetic surgeries, by calculating the finite type invariant of order 3.
Effects of neutrino electromagnetic properties and spin polarization in elastic neutrino–nucleon scattering
Authors: Kouzakov Konstantin A. , Lazarev Fedor M. , Studenikin Alexander I.
Published: December 2024

Electromagnetic neutrino properties can be a manifestation of new physics. We study electromagnetic contribution to elastic neutrino–nucleon scattering processes. Following our approach developed for the case of elastic neutrino–electron and neutrino–proton collisions, in our formalism we account for possible electromagnetic form factors of massive neutrinos: the charge, magnetic, electric and anapole form factors of both diagonal and transition types. Considering Dirac neutrinos from an astrophysical source arriving at a detector on Earth, we assume them to have arbitrary spin polarization due to effects of neutrino spin oscillations induced by neutrino magnetic moment interactions with magnetic fields both in the astrophysical source and in the interstellar environment. When treating the nucleon electromagnetic vertex, we take into account not only charge and magnetic form factors of a nucleon, but also its electric and anapole form factors. We numerically examine how the effects of electromagnetic properties and spin polarization of the cosmic neutrinos can influence the differential cross sections of their elastic scattering on nucleons in the detector.
MODELING THE EFFECTS OF PSYCHOLOGICAL FEAR, TV AND SOCIAL MEDIA ADVERTISEMENTS ON THE CONTROL OF INFECTIOUS DISEASES
Authors: VERMA MAITRI , TRIPATHI KULDEEP KUMAR , MISRA ARVIND KUMAR
Published: December 2024

In this paper, a mathematical model is proposed to study the combined effects of media awareness and fear-induced behavioral changes on the dynamics of infectious diseases. It is considered that in comparison to the unaware individuals, the aware individuals have a lower contact with infected ones. The number of media advertisements is assumed to increase at a rate proportional to the number of infected persons and declines as the number of aware individuals increases. The stability analysis of the model shows that an increase in the growth rate of media advertisements leads to generation of periodic oscillations in the system due to occurrence of Hopf-bifurcation at interior equilibrium. The fear factor and the decline in advertisements due to an increase in the number of aware individuals are found to have stabilizing effect on dynamics of system and their high values can eliminate the limit cycle oscillations present in the system. The rate at which awareness spreads among susceptible individuals and the behavioral response of the aware population are found to be the critical parameters which shape the overall impact of awareness on disease dynamics. It has been observed that the increase in contact rate of aware individuals with infected ones and the dissemination rate of awareness can result into emergence of multiple stability switches via double Hopf-bifurcation.
COMPLEXITY-BASED ANALYSIS OF THE VARIATIONS IN SKIN REACTION IN DIFFERENT EMOTIONAL STATES
Authors: KREJCAR ONDREJ , PANDEY ANAMIKA , NAMAZI HAMIDREZA
Published: December 2024

Analyzing the skin’s response to different external conditions is a significant area of research in biomedical engineering. This paper examines the variations in skin activity across different emotional states. We employed the concepts of complexity, calculating the approximate entropy (ApEn) and sample entropy (SampEn) of galvanic skin response (GSR) signals from 12 subjects who were exposed to 21 stimulus videos (three sessions), in total, categorized under six basic emotions: surprise, anger, fear, happiness, sadness, disgust, and an additional neutral state. The results demonstrated significant variations in the complexity of GSR signals across these emotional states. The methodology used in this study can also be extended to analyze other physiological signals, such as EEG, EMG, and ECG, to potentially understand the responses of various organs like the brain, muscles, and heart to different emotional stimuli.
OPTIMIZING SHOT PEENING PROCESS PARAMETERS ON SURFACE ROUGHNESS, HARDNESS, AND WEAR PROPERTIES OF Ti6Al4V PEENED WITH STAINLESS STEEL SHOTS
Authors: HARI BAALAAJI R. A. , BALASUBRAMANIAN K.
Published: December 2024

In this investigation, Ti6Al4V was used as the base material for the shot peening process. Three major influencing parameters such as peening time, peening distance, and peening pressure were examined. The substrate was shot peened with stainless steel shot, with an average diameter of 0.6[Formula: see text]mm. The process parameters were optimized using the statistical tool Response Surface Methodology. A three-factor, five-level composite design matrix was employed to minimize the number of trial runs. The effect of shot peening parameters on hardness, surface roughness, and coefficient of friction was optimized. The adequacy of the model was checked using an analysis of variance. From the test results, it was observed that the peening performed with a shot peening time of 20[Formula: see text]s, a peening distance of 100[Formula: see text]mm, and a peening pressure of 3 bar resulted in a higher hardness of 433 VHN, a surface roughness of 5.8, and a coefficient of friction of 0.22. This may be attributed to the optimal residual compressive strength achieved through the shot peening process.
EXACT SOLUTION OF RADIATIVE FLOW ON THE MIXED CONVECTION FLOW OF HYBRID NANOFLUID IN A POROUS MEDIUM: LAPLACE TRANSFORM TECHNIQUE FOR SUSTAINABLE ENERGY
Authors: ALI F. , ZAIB A. , PADMAVATHI T. , FAIZAN M. , ZAFAR S. S.
Published: December 2024

To govern the complex rheological dynamics of fluid simulations, numerous mathematical approaches are being developed. The examination of such mathematical frameworks employs theoretical, iterative, empirical, and analytical methodologies. This work analyzes and evaluates the Laplace transforms to estimate the time-dependent mixed convective flow of hybrid nanofluid in a porous material. A hybrid nanofluid is produced through dispersing molybdenum disulfide ([Formula: see text]) and silicone dioxide ([Formula: see text]) nanoparticles in carboxymethyl cellulose ([Formula: see text]). The objective of this study is to examine the heat transfer properties of a hybrid nanofluid ([Formula: see text]/[Formula: see text]) flowing over a vertical sheet while being subjected to a thermal radiation and heat source and sink. The Laplace transform approach has been used in closed form to solve the resulting partial differential equations governing the flow. This study examines how hybrid nanofluids influence time-dependent flow and heat transmission in the presence of porous medium, heat radiation, and rate of heat generation. The computer program MATHEMATICA is used to emphasize the impact of each flow parameter. Graphs are used to analyze the results of radiation, heat source, magnetic, and nanoparticle volume fraction obtained using the Laplace transform technique for engineering variables like fraction and rate of heat, as well as velocity and thermal distribution. The velocity distribution is an increasing function of mixed convective parameter. Larger values of porosity variable and mixed convection variable result in accelerating the velocity of the fluid. Additionally, we conducted research with various ratios of nanoparticles and discovered several intriguing outcomes that can be used to solve various technical issues, particularly in the cooling process.
Recap of the 32nd Annual Conference on Pacific Basin Finance, Economics, Accounting, and Management
Authors: Lee Cheng-Few , Sarath Bharat
Published: December 2024

The 32nd Annual Conference on Pacific Basin Finance, Economics, Accounting, and Management was held at Rutgers University, USA on August 29 and 30, 2024. The first conference was held at Rutgers University in 1993. Since then, the conference has been held in Hong Kong (1994, 1998), Taiwan (1995, 1999, 2003, 2006, 2011, 2016, 2019, 2020, 2022, 2023), Rutgers (1996, 2001, 2005, 2012, 2018, 2021), Singapore (1997, 2002, 2017), Bangkok (2000, 2004, 2009), Vietnam (2007, 2015), Australia (2008, 2013), China (2010), Japan (2014). The program directors of the conference were Cheng-Few Lee and Bharat Sarath, Rutgers University, USA.
Failure Feature and Restoring Force Model of Interlocking Shear Groove Between Base Plate and Main Beam Under Low Cyclic Load
Authors: Feng Yulin , Zeng Haiting , Pang Lin , Zhou Wangbao , Jiang Lizhong
Published: December 2024

Interlocking Shear Groove (ISG) between base plate and main beam serves as the connection for interaction between the longitudinal slab ballastless track (LSBT) and bridge structure. To study the failure characteristics of ISG under low cyclic loads, a test model with a 1:5 scale ratio of base plate-ISG-main beam with 4 different numbers of shear bars was designed and made. Failure mechanism, failure pattern, hysteresis curve, skeleton curve, and other failure characteristics of the ISG under low cyclic loads were studied. Based on test data multiple regression of ISG, the three-fold theoretical skeleton model and the formula were established. By analyzing the hysteretic characteristics of ISG, the hysteretic rule and stiffness degradation rule of loading and unloading are obtained, and then the restoring force model was established and verified. The results show that the failure pattern of the ISG is divided into three stages: (a) appearance of fine cracks on both sides of the interface between the ISG and main beam; (b) with the increase in loading displacement, the interface between the ISG and main beam underwent shear cracking and developed into through cracks, and the shear bars underwent shear deformation; (c) the ISG cracked and failed under the combined action of bending and shear, the upper component tilted, and the shear bars underwent bending and shear deformation. Increasing the number of shear bars in the ISG effectively increased the bearing capacity and stiffness and improved the ability to resist external loads. This led to an effective reduction in the strength and stiffness degradation rate. With the increase in the number of the shear bars, the energy dissipation ratio and energy dissipation capacity of the ISG increased, the better the seismic performance of the specimens. The established three-fold model theoretical skeleton model and the restoring force model of the ISG are in good agreement with the test data, and the calculation method of the model is simple and clear, which effectively reflects the hysteretic performance of the ISG under low cyclic loads. The research results can provide theoretical basis for seismic damage analysis of the LSBT — bridge system of HSR.
Vibration Analysis of GRA Rotating Truncated Conical Shell in Thermal Environment Under Unified Boundary Condition
Authors: Wang X. H. , Li H. , Guo X. T. , Ma W. S. , Jiang Y.
Published: December 2024

As a part of the rocket structure, the truncated conical shell will undergo extremely high temperature changes during the launch and flight of the rocket, which is particularly important for the selection of materials. The graphene-reinforced aluminum-based composites (GRA) are widely used as a new type of high-performance material. This paper mainly studies the natural vibration characteristics of the graphene-reinforced aluminum-based rotating truncated conical (GRA-RTC) shell under the unified boundary conditions by the traveling wave vibration. The innovation is to consider the temperature change with thickness in the GRA-RTC shell, and there are five uniformly distributed artificial springs at the large and small end radii of the rotating conical shell, which can obtain different elastic support boundary conditions. Three graphene distribution types are obtained along the thickness direction. The impact of the Coriolis force and initial ring tensor on the vibration of the rotating conical shell is examined in the structure. According to the first-order shear deformation theory (FSDT), strain–displacement relationship and constitutive relationship, the kinetic energy and potential energy are obtained for the GRA-RTC shell. While solving, the mode shapes of the circumferential direction and generatrix direction of the rotating conical shell are given by using trigonometric functions and Chebyshev polynomials. The ordinary differential equations of the GRA-RTC shell are attained by the Rayleigh–Ritz method, and the frequency and mode shapes are further solved for the GRA-RTC shell. This paper compares the results with Sanders’ shell theory and ANSYS Workbench, which fully verifies the accuracy of the results in this paper. The influences of the spring stiffness, graphene mass fraction, distribution type, temperature, boundary conditions and rotational speed on the frequency and mode are investigated for the GRA-RTC shell. In the study of free vibration processes, it is found that changes in rotational speed can cause mode exchange, critical resonance speed, and critical speed phenomena, which are very dangerous and can cause structural failure and damage. It provides a foundation for further research on nonlinear traveling vibration of the rotating conical shells. This paper presents a novel approach to studying rotating cylindrical and conical shells with various boundary conditions.
Dynamic Behavior of FG-GPLHS Plates with Coupled Stiffeners Under Moving Loads
Authors: Gong Qingtao , Teng Yao , Ma Binjie , Li Xin , Guo Sheng
Published: December 2024

This research investigates the dynamic behavior of functionally graded graphene platelet honeycomb sandwich (FG-GPLHS) plates coupled with stiffeners under moving loads, a critical area lacking in current research. Utilizing sandwich equivalence theory, a model of the FG-GPLHS plate is constructed, and the coupling of stiffeners is achieved through displacement continuity conditions combined with displacement coordinate transformation. Artificial virtual spring methods are employed to simulate boundary conditions and establish the force matrix for moving loads. The spectral geometry method (SGM)-Chebyshev method is employed to solve for the model, yielding insights into its dynamic behavior. This research takes into account a number of factors such as honeycomb parameters, boundary conditions, loading velocities, stiffeners cross-section properties, graphene platelet (GPL) distribution pattern and mass fraction to evaluate their effects on the vibration damping effectiveness of the structure. In particular, the effect of honeycomb dimensions and GPL parameters on the vibration resistance and stability of the model under moving loads, which can realize a wider range of application values for this structure in engineering.
An ARMAX/ARCH Model to Structural Damage Localization
Authors: Ma Lingjuan , Yi Wen , Song Xueli , Li Rongpeng , Xiao Yuzhu , Zheng Supei , Wang Kaiming
Published: December 2024

The time series methods derived from the structural dynamic equation have been effectively applied to damage localization. The current technique utilizes an autoregressive moving average with exogenous inputs (ARMAX) model, neglecting the dynamic responses of certain degrees of freedom, and approximating excitation and noise as a moving average (MA) process, which leads to an assumption of constant residual variance. However, this assumption typically reduces the damage localization accuracy by potentially overlooking structural damage information. To address these issues, this study proposes an approach using conditional standard deviation of the ARMAX and autoregressive conditional heteroskedasticity (ARCH) model residuals to further improve damage localization accuracy. Specifically, first, this method derives the ARMAX model from the structural motion equations, with the autoregressive and input term orders fixed. Second, the excitation, noise, and dynamic responses of degrees of freedom in other directions are considered residuals, which are then modeled as the MA process to ensure whiteness and the ARCH model to account for heteroscedasticity, thereby enhancing structural information capture. Finally, the damage feature, defined as the ratio of the conditional standard deviation of the ARCH model residuals in the test state to that in the reference state, is used to identify damage localization. Numerical simulations and experimental results from Los Alamos National Laboratory indicate that the proposed method significantly enhances damage localization accuracy compared to the existing ARMAX model.
A New Modified Couple Stress Finite Element Model for Buckling Analysis of Laminated CNTs-Reinforced Composite Microplate
Authors: Nguyen Xuan Thinh , Hoang-Le Minh , Khatir Samir , Tran Minh Thi , Cuong-Le Thanh
Published: December 2024

This paper aims to develop a size-dependent numerical solution for a comprehensive study on the buckling responses of laminated functionally graded (FG) carbon nanotubes (CNTs)-reinforced composite microplates under linear and nonlinear in-plane compressive loading. According to the new modified couple stress theory and isogeometric analysis (IGA), in conjunction with the higher order plate theory, the size-dependent governing motion equations including material length scale parameter for buckling analysis of CNTs-reinforced laminated composite microplates is established. The research considers five types of loading shapes: uniform, triangular, trapezoidal, sinusoidal, and parabolic. The distribution of CNTs varies across the layer’s thickness, either uniformly or functionally patterns. The material properties of the composite layer are derived by using the New rule of mixture. The accuracy and reliability of the present solution are verified by comparing them with existing models. Different numerical examples illustrate the influences of various parameters on buckling responses of laminated FG-CNTs-reinforced composite microplates. These parameters include size-dependent effects, aspect ratio, volume fraction and distribution of CNTs, fiber orientation, lamination scheme, and boundary conditions. Additionally, the study considers a complex geometry of laminated microplates with flower cutouts to provide a comprehensive analysis.
Microwave-Assisted Green Synthesis and Characterization of Silver Nanoparticles Using Neem Extract and Evaluation of Biomedical Properties
Authors: Mudhafar Mustafa , Zaid Khayr , Al-Marzook Farah A. , Alsailawi H. A. , Zainol Ismail , Al-Asady Aabdulridha Mohammed , Hussein Rafal Muhammed , Zorah Mohammed
Published: December 2024

This study aimed to synthesize, physicochemical characterize, and evaluate the biomedical properties of silver nanoparticles (AgNPs). The methodology section included using two green methods to synthesize silver nanoparticles and comparing them to be chosen appropriately by future researchers. Two samples were obtained: one from green microwave-assisted (MSGS) called AgNPs-1 and the second sample prepared by rapid synthesis method called AgNPs-2; these samples were characterized for their physicochemical using X-ray Powder Diffraction (XRD), Dynamic Light Scattering (DLS), Fourier-transform infrared spectroscopy (FTIR), Energy-dispersive X-ray spectroscopy (EDX). Moreover, the biomedical properties were evaluated by determining the antibacterial and cytotoxicity studies. The results observed two peaks in the UV–Vis spectroscopy were indicated at 446[Formula: see text]nm and 454[Formula: see text]nm for AgNPs-2 and AgNPs-1, respectively, which first revealed the different particle sizes and conformed in the XRD. DLS showed that the particle sizes of AgNPs-2 were 84.30[Formula: see text]nm and 121[Formula: see text]nm, respectively, while AgNPs-1 were 120.20[Formula: see text]nm and 437[Formula: see text]nm, respectively. The morphology of the synthesized samples was investigated using scanning electron microscopy (SEM) and showed different shapes, which were spherical and spherical-rod for AgNPs-2 and AgNPs-1, respectively. The presence of the silver element was indicated at 3[Formula: see text]KeV in EDX for both samples. The antibacterial test showed a significant ability to inhibit the growth of the four evaluated bacteria, and AgNPs-2 showed more effect than AgNPs-1 because of the size of the particles. The cytotoxicity study showed no toxic effect, and the average cell availability of HeLa cells was 91%. The current research demonstrated that new products from natural materials have good antibacterial properties that can be used as antibiotics with nontoxic effects in the biomedical field.
Exploring relationship between hypercholesterolemia and instability of atherosclerotic plaque — An approach based on a matrix population model
Authors: Twardawa Mateusz , Gutowska Kaja , Formanowicz Piotr
Published: December 2024

Background: Cardiovascular diseases have long been studied to identify their causal factors and counteract them effectively. Atherosclerosis, an inflammatory process of the blood vessel wall, is a common cardiovascular disease. Among the many well-known risk factors, hypercholesterolemia is undoubtedly a significant condition for atherosclerotic plaque formation and is linked to atherosclerosis on many levels, i.e. cell interactions, cytokines levels, diet, and lifestyle. Current studies suggest that controlling balance between proinflammatory (M1) and anti-inflammatory (M2) types of macrophages may be used for patient condition improvement and necrotic core reduction. Methods: This study considered the effects of hypercholesterolemia on the population dynamics of macrophages (M0, M1, M2, foam cells) in atherosclerotic plaque. A mathematical model using a matrix approach to population dynamics was proposed and tested in various scenarios. In order to check model sensitivity and variability associated with error propagation, the uncertainty analysis was performed based on the Monte Carlo approach. Results: Simulations of macrophage population dynamics provided the assessment of necrotic core development and plaque instability. Excess lipid levels emerged as the most critical factor for necrotic core development. However, plaque growth can be significantly slowed if macrophages and foam cells can maintain proper lipid levels. This balance may be disrupted by proinflammatory lipids that eventually will increase plaque size, what is also reflected by M1/M2 dynamics. Conclusion: Hypercholesterolemia accelerates atherosclerosis development, leading to earlier cardiovascular incidents. In silico results suggest that reducing lipid intake and portion of proinflammatory lipids is crucial to slowing plaque development and reducing rupture risk, all of which requires preserving fragile M1/M2 balance. Targeting the inflammatory microenvironment and macrophage polarization represents a promising approach for atherosclerosis management.
Formulation of a New Finite Element with Drilling Rotation Based on Assumed Strains for Membrane Structures
Authors: Abderrahmani Sifeddine
Published: December 2024

A new membrane finite element with four nodes that is based on the strain approach using Airy’s function is developed for the resolution of plane linear elasticity problems in general. The adoption of linear variations for the normal components of the strain and constant shear strain improves the accuracy of the elements. However, any singularity is eliminated by the use of a local reference frame oriented in an optimal manner. From numerical examples of a beam subjected to bending and shearing, we conclude that exact solutions can be obtained and they demonstrate the accuracy of the proposed procedure.
Sectoral Analysis of Environment Social and Governance Data Using Deep Learning Model
Authors: Rangasamy Sangeetha , Rajamohan Kavitha , Deb Darpan , Pillada Naga
Published: December 2024

The relevance of sustainable practices in businesses is indispensable due to the rising global concerns over climate threats and carbon emissions. Integrating Environmental, Social, and Governance (ESG) factors into business models and operations has become the need of the hour. This radical shift in business operations is propelled by the Sustainable Development Goals (SDGs) set up by the United Nations (UN). The advent of newer technologies, especially Machine Learning (ML) and Deep Learning (DL), has aided firms in data assimilation and evaluating their sustainable practices. However, a notable research gap remains in examining ESG integration in the processes and procedures of corporations through AI algorithms. This is due to the challenges of gathering comprehensive ESG-related data and the need for detailed comparative sectoral analysis. The impact and correlation of ESG scores on a firm’s financial performance have been studied, but a sectoral analysis across the globe needs to be done. The use of ML models for the textual and numerical data accumulation analysis is pertinent. The present study aims to provide a data-driven comparative analysis of three chosen sectors with the help of Artificial Intelligence (AI). This research paper focuses on the environmental domain, as the climate threats and opportunities need an appropriate policy for implementation. This study utilizes the vast repository of ESG disclosure data from the Bloomberg database for the energy, consumer durables, and pharmaceutical sectors, covering global and Indian perspectives for comparative analysis. These three sectors provide pivotal data for addressing sustainability challenges regarding the Climate and Emission categories. The research and interpretation of numerical data are done with the help of the DL model and language model Bidirectional Encoder Representations from Transformers (BERT), which analyzes the textual data from social media. The study highlights the challenges associated with ESG integration among the chosen sectors on a global platform. The findings from this study can contribute significantly to the ongoing sustainability dialogue and policy formulation.
Dynamical behavior of solitons in the Landau–Ginzburg–Higgs equation by using efficient techniques
Authors: Iqbal Ifrah , Alessa Nazek , Shahzad M. Umair , Ur Rehman Hamood , Muneer Sadia , Zotos Euaggelos E.
Published: December 2024

This paper investigates the dynamics of the nonlinear Landau–Ginzburg–Higgs equation within the domain of superfluids and Bose–Einstein condensates. The primary focus is on exploring novel exact solutions within this equation. To obtain soliton solutions of the proposed nonlinear model, a modified Sardar sub-equation method and an extended modified tanh function method are employed. From a significant physical perspective, a diverse range of solutions is presented, encompassing bright solitons, dark solitons, singular solitons, combo dark-bright solitons, dark-singular solitons, periodic solutions, exponential solutions, and rational solutions. The study utilizes 2D and 3D visualizations of the computed wave solutions to effectively illustrate the internal structure of the phenomenon. This study also presents a comparative analysis of wave speed parameters using 2D graphs. By visualizing these parameters, the research highlights the variations and intricate behavior of the soliton solutions, further enhancing the understanding of the nonlinear Landau–Ginzburg–Higgs equation. The study marks the first application of the modified Sardar subequation method and the extended modified tanh function method to the nonlinear Landau–Ginzburg–Higgs equation. This combination provides a comprehensive model for capturing complicated biological and physical events, with increased predictive power and adaptability.
3D-Printed Nonuniform Lattice Metamaterials with Programmable Poisson’s Ratio
Authors: Zhang Jingyi , Liu Yuheng , Lu Haibao , Tao Ran
Published: December 2024

This research presents a novel design method for mechanical metamaterials with programmable Poisson’s ratio. Poisson’s ratio of metamaterials can be quantitatively controlled by geometric parameters such as the side length of the rhombus, rhombus angle, and reentrant angle. The parametric study was conducted through finite element method (FEM) analysis, revealing the influence of geometric parameters on Poisson’s ratio and nominal modulus. The FEM results have a good agreement with the experiments. Additionally, based on the design concept of nonuniform stiffness, we have designed different structural parameters for different areas to achieve multiple Poisson’s ratio effects within the same structure. Ultimately, two types of nonuniform stiffness metamaterials, featuring distinct three Poisson’s ratios and asymmetrical Poisson’s ratios were obtained, respectively. This work expands the design methods in the research of programmable Poisson’s ratio metamaterials and provides guidance for the design of nonuniform stiffness lattice structures with tunable Poisson’s ratio.
An Inventory Model of a Decaying Item with Fuzzy Lifetime and Decay Rate under Dynamic Trade Credit and Variable Demand
Authors: Kumar Gautam , Maiti Manas Kumar , Samanta Guruprasad , Maiti Manoranjan
Published: December 2024

An inventory model of a decaying item is proposed considering dynamic credit period to the consumers, fuzzy life time of the units, time-dependent fuzzy decaying rate, and freshness dependent dynamic imprecise demand. Decaying rate of units depends on its lifetime and is considered as a dynamic monotonic increasing function of the same. To encourage the consumers, the retailer provides a credit on a part of the purchase and due to the dynamic decreasing nature of the freshness of units, the credit interval is considered as dynamic increasing. The unit cost, consumer credit period, and credit amount have impact on demand. As demand is fuzzy, some units may left at any cycle ending and are put up for sell in lot in a lump sum price. The model is formulated using fuzzy mathematical tools to decide the optimal cycle length, unit selling price, and order quantity to optimize the annual fuzzy profit from a cycle. A modified form of particle swarm optimization is applied to get the best decision, in which, using fuzzy credibility measure the objectives corresponding to two feasible solutions are compared to select the better one. Proper fuzzy simulation approaches are followed to determine the required credibility measures.