bluuebunny/crossref_metadata_2025 huggingface dataset:
Femtosecond Laser Irradiation to Zirconia Prior to Calcium Phosphate Coating Enhances Osteointegration of Zirconia in Rabbits
Authors: Mutsuzaki Hirotaka , Yashiro Hidehiko , Kakehata Masayuki , Oyane Ayako , Ito Atsuo
Published: February 2024

Calcium phosphate (CaP) coating of zirconia and zirconia-based implants is challenging, due to their chemical instability and susceptibility to thermal and mechanical impacts. A 3 mol% yttrium-stabilized tetragonal zirconia polycrystal was subjected to femtosecond laser (FsL) irradiation to form micro- and submicron surface architectures, prior to CaP coating using pulsed laser deposition (PLD) and low-temperature solution processing. Untreated zirconia, CaP-coated zirconia, and FsL-irradiated and CaP-coated zirconia were implanted in proximal tibial metaphyses of male Japanese white rabbits for four weeks. Radiographical analysis, push-out test, alizarin red staining, and histomorphometric analysis demonstrated a much improved bone-bonding ability of FsL-irradiated and CaP-coated zirconia over CaP-coated zirconia without FsL irradiation and untreated zirconia. The failure strength of the FsL-irradiated and CaP-coated zirconia in the push−out test was 6.2–13.1-times higher than that of the CaP-coated zirconia without FsL irradiation and untreated zirconia. Moreover, the adhesion strength between the bone and FsL-irradiated and CaP-coated zirconia was as high as that inducing host bone fracture in the push-out tests. The increased bone-bonding ability was attributed to the micro-/submicron surface architectures that enhanced osteoblastic differentiation and mechanical interlocking, leading to improved osteointegration. FsL irradiation followed by CaP coating could be useful for improving the osteointegration of cement-less zirconia-based joints and zirconia dental implants.
Optimizing AUV Navigation Using Factor Graphs with Side-Scan Sonar Integration
Authors: Zhang Lin , Gao Yanbin , Guan Lianwu
Published: February 2024

For seabed mapping, the prevalence of autonomous underwater vehicles (AUVs) employing side-scan sonar (SSS) necessitates robust navigation solutions. However, the positioning errors of traditional strapdown inertial navigation system (SINS) and Doppler velocity log (DVL) systems accumulated significantly, further exacerbated by DVL’s susceptibility to failure in complex underwater conditions. This research proposes an integrated navigation approach that utilizes factor graph optimization (FGO) along with an improved pre-integration technique integrating SSS-derived position measurements. Firstly, the reliability of SSS image registration in the presence of strong noise and feature-poor environments is improved by replacing the feature-based methods with a Fourier-based method. Moreover, the high-precision inertial measurement unit (IMU) pre-integration method could correct the heading errors of SINS significantly by considering the Earth’s rotation. Finally, the AUV’s marine experimental results demonstrated that the proposed integration method not only offers improved SSS image registration and corrects initial heading discrepancies but also delivers greater system stability, particularly in instances of DVL data loss.
Population Genetics Assessment of the Model Coral Species Stylophora pistillata from Eilat, the Red Sea
Authors: Rachmilovitz Elad Nehoray , Douek Jacob , Rinkevich Baruch
Published: February 2024

The successful management of coral reefs necessitates understanding the genetic characteristics of reefs’ populations since levels of genetic diversity play a critical role in their resilience, enabling them to withstand environmental changes with greater efficacy. To assess the genetic diversity and connectivity of the widespread Indo-Pacific coral, Stylophora pistillata, eight microsatellite loci were employed on 380 tissue samples collected from eight sites along the northern Gulf of Eilat, Red Sea. We documented deviations from the Hardy–Weinberg equilibrium and observed low heterozygosity and high values of expected heterozygosity (0.59 and 0.82, respectively). The relatively high FST values and STRUCTURE analysis results showed population fragmentation along the short coastline (<12 km). These results signify isolation by distance, low gene flow between most populations, and possible non-random mating. These results are connected to this species’ sexual reproduction traits, a brooding coral species with planulae that settle shortly upon release with limited connectivity that are most probably further exacerbated by anthropogenic impacts imposed on Eilat’s reefs. This study provides insights into the connectivity and population genetics of S. pistillata residing in an urbanized northern Red Sea reef and reinforces the need for better management of the current MPA, employing future active coral reef restoration in the area.
The Wide-Area Coverage Path Planning Strategy for Deep-Sea Mining Vehicle Cluster Based on Deep Reinforcement Learning
Authors: Xing Bowen , Wang Xiao , Liu Zhenchong
Published: February 2024

The path planning strategy of deep-sea mining vehicles is an important factor affecting the efficiency of deep-sea mining missions. However, the current traditional path planning algorithms suffer from hose entanglement problems and small coverage in the path planning of mining vehicle cluster. To improve the security and coverage of deep-sea mining systems, this paper proposes a cluster-coverage path planning strategy based on a traditional algorithm and Deep Q Network (DQN). First, we designed a deep-sea mining environment modeling and map decomposition method. Subsequently, the path planning strategy design is based on traditional algorithms and DQN. Considering the actual needs of deep-sea mining missions, the mining vehicle cluster path planning algorithm is optimized in several aspects, such as loss function, neural network structure, sample selection mechanism, constraints, and reward function. Finally, we conducted simulation experiments and analysis of the algorithm on the simulation platform. The experimental results show that the deep-sea mining cluster path planning strategy proposed in this paper performs better in terms of security, coverage, and coverage rate.
The Relationship between Endophytic Fungi of Chimonanthus praecox and Volatile Metabolites under Different Circadian Rhythms and Blooming Stages
Authors: Li Yue , Hei Jingying , He Xiahong , Rui Rui , Wang Shu
Published: February 2024

Chimonanthus praecox is an aromatic plant that flowers in winter. The composition of the floral volatiles of C. praecox is influenced by different blooming stages, circadian rhythms and species. However, the relationship between floral volatiles and plant endophytic fungi has not received much research attention. Here, we used high-throughput sequencing technology to compare and analyze the changes in the structure and diversity of the endophytic fungal communities in C. praecox under different circadian rhythms (7:00 a.m., 1:00 p.m., and 7:00 p.m.) and in different blooming stages (unopened flowers and opened flowers). The endophytic fungi of C. praecox consisted of nine phyla, 34 classes, 79 orders, 181 families, 293 genera, and 397 species, and Ascomycota was the dominant phylum. Under a diurnal rhythm, the diversity (Chao1 and Shannon indices) of endophytic fungi gradually decreased in the unopened flowers, while an increasing and then decreasing trend was found for the opened flowers. In the different blooming stages, the endophytic fungal diversity was significantly higher at 7:00 a.m. in the unopened flowers compared to the opened flowers. Humidity was the key factors that significantly affected the endophytic fungal diversity and community. Moreover, 11 endophytic fungi were significantly positively or negatively correlated with seven floral volatiles. In conclusion, the community structure and diversity of endophytic fungi in C. praecox were affected by the different blooming stages and circadian rhythms, and a correlation effect related to floral volatiles was found, but there are other possible reasons that were not tested. This study provides a theoretical basis for elucidating the interrelationships between endophytic fungi, floral volatiles, and environmental factors in C. praecox.
Associations between Mediterranean Diet Adherence, Quality of Life, and Mental Health in Patients with Multiple Sclerosis: A Cross-Sectional Study
Authors: Dakanalis Antonios , Tryfonos Christina , Pavlidou Eleni , Vadikolias Konstantinos , Papadopoulou Sousana K. , Alexatou Olga , Vorvolakos Theofanis , Chrysafi Maria , Fotiou Dimitrios , Mentzelou Maria , Serdari Aspasia , Chatzidimitriou Maria , Dimoliani Sophia , Tsourouflis Gerasimos , Giaginis Constantinos
Published: February 2024

Background: The Mediterranean diet (MD) is well-known as a diet which may exert a protective effect against neurodegenerative diseases, including multiple sclerosis (MS). To date, only a few clinical surveys have assessed the potential effects of the MD in patients with MS. The purpose of the present study is to evaluate the potential effects of MD compliance on disease disability, quality of life, physical activity, depressive symptomatology, and blood biochemical parameters related to nutritional status in MS patients, considering several socio-demographic, anthropometric, and lifestyle characteristics. Methods: This is a cross-sectional study conducted on 558 adults with MS aged 18–64 years. Relevant questionnaires were utilized to evaluate socio-demographic and anthropometric parameters, disease disability (Expanded Disability Status Scale, EDSS), multidimensional health-related quality (MS Quality of Life-54, MSQOL-54), physical activity levels (International Physical Activity Questionnaire, IPAQ), depression (Beck Depression Inventory II, BDI-II), and MD adherence (MedDietScore), while several blood biochemical parameters were retrieved from the patients’ medical records. Results: Enhanced MD compliance was independently associated with a decreased frequency of overweight/obesity, as well as abdominal obesity, in patients suffering from MS. Elevated MD compliance was also independently associated with a decreased incidence of advanced disease disability, a higher prevalence of elevated physical activity, an improved quality of life, and lower depressive symptoms, as well as higher levels of certain blood biochemical parameters, which are effective indicators of iron deficiency and malnutrition. Conclusions: The present study found that higher MD adherence may slow down disease disability, promoting a better quality of life and mental health in adults with MS. Future prospective surveys are required to obtain conclusive results.
Insights into Sustainability Reporting: Trends, Aspects, and Theoretical Perspectives from a Qualitative Lens
Authors: Dincer Banu , Dincer Caner
Published: February 2024

This review aims to provide a comprehensive synthesis of the coverage of sustainability reporting (SR) aspects within the corpus of qualitative SR literature. It seeks to elucidate the theoretical and conceptual foundations that have guided the trajectory of the sustainability field and illuminate the qualitative methodologies used in this body of literature. Employing a systematic review methodology, this study undertakes an exhaustive examination of 242 selected empirical studies on sustainability reporting conducted during the period spanning from 2001 to 2022. The noteworthy contribution of this review to the realm of sustainability research lies in its identification of unexplored and underexplored domains that merit attention in forthcoming investigations. These include but are not limited to employee health and safety practices, product responsibility, and gender dynamics. While stakeholder theory and institutional theory have been dominant theories within the selected literature, the exploration of moral legitimacy remains largely underinvestigated. It is essential to underscore that this review exclusively encompasses qualitative studies, owing to the richness and versatility inherent in qualitative research methods. This deliberate selection enables researchers to employ diverse methodological and theoretical frameworks to gain a profound understanding of engagement within the practice of sustainability reporting. This review introduces an interesting approach by considering the thematic scope, as well as theoretical and methodological choices, observed across the selected studies.
The New Normalcy and the Pandemic Threat: A Real Option Approach
Authors: Scandizzo Pasquale Lucio , Knudsen Odin K.
Published: February 2024

This paper delves into the evolving post-pandemic business arena, focusing on how liability options and social norms are reshaping industry structures. We anticipate lasting transformations due to the emergence of new safety standards that bridge the gap between corporate interests and societal welfare. To foster these changes, effective post-lockdown economic policies could encompass not only rigorous social standards but also specific financial incentives. Examples of such incentives include tax relief for businesses implementing comprehensive health protocols and subsidies for those transitioning to remote work or modifying production layouts to minimize infection risks. Our analysis delineates two predominant operational frameworks for firms in this new environment: the liability and property regimes. These are determined by each firm’s financial outcomes and the extent of damages incurred, all measured against societal expectations. Firms within the liability regime may exhibit only partial compliance, often attributed to ambiguous standards and prevailing uncertainties, potentially leading to a dip in profits. In contrast, entities operating under the property regime are likely to engage in more extensive organizational restructuring. A key insight from our study is the paradigm shift in investment behavior, increasingly influenced by risk management, particularly in the strategic choice between liability and property rules. This shift is evident in how firms now prioritize managing potential external liabilities, such as environmental hazards or evolving regulatory landscapes, in their investment decisions. Consequently, the traditional growth-centric investment paradigm is being supplemented by strategies that emphasize safeguarding against various external risks, marking a significant realignment in corporate investment philosophies post-pandemic. This transition underscores the intricate interplay between economic policies, corporate strategies, and societal dynamics in the contemporary business milieu.
Spatiotemporal Evolution, Spatial Agglomeration and Convergence of Environmental Governance in China—A Comparative Analysis Based on a Basin Perspective
Authors: Xu Mengzhi , Luan Shixin , Gao Xuan , Wang Huachun
Published: February 2024

Scientifically measuring the level of environmental governance (EGL) and understanding its spatial convergence has important reference value for ecological governance. In this paper, the global entropy method is applied to measure the EGL of 284 prefecture-level cities in China from 2007 to 2019, which are divided into three major river basins, including the Yellow River, Yangtze River, and Pearl River, to observe the spatial–temporal evolutionary characterization through a standard deviation ellipse model. The coefficient of variation and the spatial econometric model are the tools used to conduct the spatial convergence test. The results are as follows: (1) China’s EGL is low overall, though it is fluctuating upward at low magnitude, and the three major river basins follow the ranking: The Pearl River Basin > The Yangtze River Basin > The Yellow River Basin. (2) Spatially, the distribution pattern of China’s EGL changes from “scattered and sporadic” to “multipolar core”. (3) The center of China’s environmental governance was concentrated in the east from 2007 to 2019, and the EGL in the midstream and downstream regions of the three major river basins increased rapidly. (4) Environmental governance in China has significant absolute and conditional β-convergence characteristics, as do the three major basins, while the ranking of convergence speed remains “Yangtze River Basin > Yellow River Basin > Pearl River Basin”. Of these, economic development accelerated the convergence rate of environmental governance in China and its three major river basins; financial pressure significantly inhibited the convergence of the EGL of the Yellow River Basin. The improvement of the EGL in the Pearl River Basin was also negatively influenced by the industrial structure.
Solvatochromic and Computational Study of Some Cycloimmonium Ylids
Authors: Babusca Daniela , Vleoanga Andrei , Dorohoi Dana Ortansa
Published: February 2024

This article contains a comparative spectral analysis corroborated with the quantum mechanical computations of four cycloimmonium ylids. The spectral shift of the visible electronic absorption band of the studied molecules in 20 solvents with different empirical parameters is expressed by linear multi-parametric dependences that emphasize the intramolecular charge transfer (ICT) process. The nature of molecular interactions and their contribution to the spectral shift of the visible ICT band of solutes are also established in this manuscript. The results of the statistical analysis are used to estimate the cycloimmonium ylids’ excited dipole moment by the variational method, using the hypothesis of McRae. The importance of the structure of both the heterocycle and carbanion substituents to the stability and reactivity of the studied cycloimmonium ylids is underlined by the quantum mechanical computations of the molecular descriptors.
Electrical Impedance Spectroscopy for Precise Film Thickness Assessment in Line Contacts
Authors: Manjunath Manjunath , Hausner Simon , Heine André , De Baets Patrick , Fauconnier Dieter
Published: February 2024

In this article, we focus on utilising electrical impedance spectroscopy (EIS) for the assessment of global and contact impedances in roller bearings. Our primary objective is to establish a quantitative prediction of lubricant film thickness in elasto-hydrodynamic lubrication (EHL) and investigate the impedance transition from ohmic to capacitive behaviour as the system shifts from boundary lubrication to EHL. To achieve this, we conduct measurements of electrical impedance, bearing and oil temperature, and frictional torque in a cylindrical roller thrust bearing (CRTB) subjected to pure axial loading across various rotational speeds and supply oil temperatures. The measured impedance data is analysed and translated into a quantitative measure of lubricant film thickness within the contacts using the impedance-based and capacitance-based methods. For EHL, we observe that the measured capacitance of the EHL contact deviates from the theoretical value based on a Hertzian contact shape by a factor ranging from 3 to 11, depending on rotational speed, load, and temperature. The translation of complex impedance values to film thickness, employing the impedance and capacitance method, is then compared with the analytically estimated film thickness using the Moes correlation, corrected for inlet shear heating effects. This comparison demonstrates a robust agreement within 2% for EHL film thickness measurement. Monitoring the bearing resistance and capacitance via EIS across rotational speeds clearly shows the transition from boundary to mixed lubrication as well as the transition from mixed lubrication to EHL. Finally, we have observed that monitoring the electrical impedance appears to have the potential to perform the run-in of bearings in a controlled way.
2-Benzoyl-4-phenyl-1,2,5-thiadiazol-3(2H)-one 1,1-Dioxide
Authors: Broumidis Emmanouil , Patterson Samuel B. H. , Rosair Georgina M. , Koutentis Panayiotis A. , Kalogirou Andreas S.
Published: February 2024

3,5-Diphenyl-4H-1,2,6-thiadiazin-4-one treated with meta-chloroperoxybenzoic acid undergoes an oxidative ring contraction to give 2-benzoyl-4-phenyl-1,2,5-thiadiazol-3(2H)-one 1,1-dioxide in a 29% yield, the structure of which is supported by single-crystal X-ray diffraction analysis and the available spectroscopic data.
Performance of Large Area n-TOPCon Solar Cells with Selective Poly-Si Based Passivating Contacts Prepared by PECVD Method
Authors: Liu Zhaobin , Guo Chunlin , Liu Ya , Wang Jianhua , Su Xuping , Wang Qinqin
Published: February 2024

Selective emitter (SE) technology significantly influences the passivation and contact properties of n-TOPCon solar cells. In this study, three mask layers (SiOx, SiNx, and SiOxNy) were employed to fabricate n-TOPCon solar cells with phosphorus (P)-SE structures on the rear side using a three-step method. Additionally, phosphosilicon glass (PSG) was used to prepare n-TOPCon solar cells with P-SE structure on the rear side using four-step method, and the comparative analysis of electrical properties were studied. The SiOx mask with a laser power of 20 W (O2 group) achieved the highest solar cell efficiency (Eff, 24.85%), The open-circuit voltage (Voc) is 2.4 mV higher than that of the H1 group, and the fill factor (FF) is 1.88% higher than that of the L1 group. Furthermore, the final Eff of solar cell is 0.17% higher than that of the L1 group and 0.20% higher than that of the H1 group. In contrast, using the four-step method and a laser power of 20 W (P2 group), a maximum Eff of 24.82% was achieved. Moreover, it exhibited an Voc, which is elevated by 3.2 mV compared to the H1 group, and FF increased by 1.49% compared to the L1 group. Furthermore, the overall Eff of the P2 group outperforms both the L1 and H1 groups by approximately 0.14% and 0.17%, respectively. In the four-step groups, the Eff of each laser condition group was improved compared with the L1 group and H1 group, The stability observed within the four-step method surpassed that of the three-step groups. However, in terms of full-scale electrical properties, the three-step method can achieve comparable results as those obtained from the four-step method. This research holds significant guiding implications for upgrading the n-TOPCon solar cell rear-side technology during mass production.
Acceleration Mechanism of Steel Slag Hydration Using THEED
Authors: Yue Deyu , Wang Jianfeng , Huo Pengchen , Chang Lei , He Dingyong , Cui Suping , Liu Hui
Published: February 2024

In this paper, the strength development of a pure steel slag (SS) system with various concentrations of N,N,N′,N′-Tetrakis-(2-hydroxyethyl) ethylenediamine (THEED) was investigated. The hydration kinetics, pore structure and microstructure of SS pastes with and without THEED were characterized to underscore the working mechanism of THEED. Results show that THEED additions significantly increase the 3, 7 and 28 days compressive strength of hardened SS pastes. The enhancement effect increases with the dosage of THEED. At a concentration of 2000 ppm, THEED increased the compressive strength by 733%, 665%, and 545% at 3, 7 and 28 days, respectively. It is confirmed that THEED additions improve the hydration degree of SS by accelerating hydration of the aluminum phase (C3A, PDF-38-1429; C12A7, PDF-48-1882) and C2F,( PDF 38-0408) to generate Mc (PDF-41-0219) and Pa (PDF-30-0222) in the presence of CaCO3. Also, the hydration degree of silicates is increased by THEED. In this way, THEED additions refine the pore structure of hardened SS paste by increasing the pore volume with a diameter below 300 nm to achieve enhancement. The chelating effect of THEED results in promoting dissolution of SS, which provides the driving force for accelerating SS hydration.
Characterization and Analysis of Corrosion Resistance of Rubber Materials for Downhole Tools in a High-Stress Environment with Coupled H2S-CO2
Authors: Gong Leilei , Chen Yulin , Cai Meng , Li Junliang , Lu Qiuyu , Hou Duo
Published: February 2024

In the process of constructing deep natural gas wells in Sichuan and Chongqing, gas wells encounter various technical challenges such as high temperature, high pressure, and a corrosive environment containing H2S and CO2. The corrosion of rubber materials in these acidic environments can easily lead to seal failure in downhole tools. To better investigate the corrosion resistance of rubber materials in acidic environments, we utilized a dynamic cyclic corrosion experimental device capable of simulating the service conditions experienced by downhole tools under high-temperature, high-pressure multiphase flow. Corrosion-resistance tests were conducted on fluororubbers (FKM) 1, 2, 3, and HNBR (hydrogenated nitrile-butadiene rubber) under acidic conditions (80 °C and 160 °C), along with sealing corrosion tests on O-rings. These tests aimed to analyze the mechanical properties, hardness, and corrosion resistance before and after exposure to acid media as well as the sealing performance of O-rings. Ultimately, our goal was to identify suitable rubber materials for acidic pressure environments. Experimental results revealed that all four types of rubber exhibited decreased elongation at break after undergoing corrosion testing; however, fluororubber 3 demonstrated significant susceptibility to temperature effects while the other three types showed minimal impact from temperature variations. Fluororubber 1 and fluororubber 3 displayed substantial deformation levels whereas mechanical properties greatly deteriorated for fluororubber 2. Overall, HNBR showcased superior comprehensive performance.
A Planar Cable-Driven Under-Sensing Model to Measure Forces and Displacements
Authors: Muscolo Giovanni Gerardo , Fiorini Paolo
Published: February 2024

This paper presents a planar cable-driven model of a simple mechanism that is able to measure forces and displacements. Recently, a preliminary study based on a cable-driven sensitive mechanism was presented to the research community, underlining the innovative characteristics of the model in under-actuation and under-sensing. The core of the research work was to conceive a compliant system able to measure forces and displacements from a point located in a different zone with respect to the one where the force is applied, and this is possible thanks to cable-driven systems. In this paper, a new simplified model with respect to our published work is presented, reducing the number of cables and including the calculation of friction in the developed test bench. The formulation to calculate the displacement of the point of the applied force and the formulation to calculate the force are presented and validated with a simulation and by using a real test bench for experimentation. A multi-body system is used for the simulation, and the results are compared and discussed. Four cases are analysed to test the formulation, including the friction in pulleys and in the joint connection between the mobile part and the fixed part of the mechanism. Future works will be oriented toward reducing the dimensions of the conceived mechanism in order to implement the model in minimally invasive robotic surgery instruments.
Experimental Thermal Conductivity Studies of Agar-Based Aqueous Suspensions with Lignin Magnetic Nanocomposites
Authors: Gautam Bishal , Nabat Al-Ajrash Saja M. , Hasan Mohammad Jahid , Saini Abhishek , Watzman Sarah J. , Ureña-Benavides Esteban , Vasquez-Guardado Erick S.
Published: February 2024

Nanoparticle additives increase the thermal conductivity of conventional heat transfer fluids at low concentrations, which leads to improved heat transfer fluids and processes. This study investigates lignin-coated magnetic nanocomposites (lignin@Fe3O4) as a novel bio-based magnetic nanoparticle additive to enhance the thermal conductivity of aqueous-based fluids. Kraft lignin was used to encapsulate the Fe3O4 nanoparticles to prevent agglomeration and oxidation of the magnetic nanoparticles. Lignin@Fe3O4 nanoparticles were prepared using a pH-driven co-precipitation method with a 3:1 lignin to magnetite ratio and characterized by X-ray diffraction, FT-IR, thermogravimetric analysis, and transmission electron microscopy. The magnetic properties were characterized using a vibrating sample magnetometer. Once fully characterized, lignin@Fe3O4 nanoparticles were dispersed in aqueous 0.1% w/v agar–water solutions at five different concentrations, from 0.001% w/v to 0.005% w/v. Thermal conductivity measurements were performed using the transient line heat source method at various temperatures. A maximum enhancement of 10% in thermal conductivity was achieved after adding 0.005% w/v lignin@Fe3O4 to the agar-based aqueous suspension at 45 °C. At room temperature (25 °C), the thermal conductivity of lignin@Fe3O4 and uncoated Fe3O4 agar-based suspensions was characterized at varying magnetic fields from 0 to 0.04 T, which were generated using a permanent magnet. For this analysis, the thermal conductivity of lignin magnetic nanosuspensions initially increased, showing a 5% maximum peak increase after applying a 0.02 T magnetic field, followed by a decreasing thermal conductivity at higher magnetic fields up to 0.04 T. This result is attributed to induced magnetic nanoparticle aggregation under external applied magnetic fields. Overall, this work demonstrates that lignin-coated Fe3O4 nanosuspension at low concentrations slightly increases the thermal conductivity of agar aqueous-based solutions, using a simple permanent magnet at room temperature or by adjusting temperature without any externally applied magnetic field.
Laplace Transformation of the Ruin Time for a Risk Model with a Parisian Implementation Delay
Authors: Sun Tao , Zhang Xinqiu
Published: February 2024

In this paper, we apply the concept of the Parisian implementation delay to dividend payments and assume that the claim amount paid Zi by the insurance company for the ith time follows an exponential distribution. We give the Laplace transformation of the ruin time for a risk model with a Parisian implementation delay and give display expressions using the scale function.
Nonlinear Phenomena of Fluid Flow in a Bioinspired Two-Dimensional Geometric Symmetric Channel with Sudden Expansion and Contraction
Authors: Yang Liquan , Yang Mo , Huang Weijia
Published: February 2024

Inspired by the airway for phonation, fluid flow in an idealized model within a sudden expansion and contraction channel with a geometrically symmetric structure is investigated, and the nonlinear behaviors of the flow therein are explored via numerical simulations. Numerical simulation results show that, as the Reynolds number (Re = U0H/ν) increases, the numerical solution undergoes a pitchfork bifurcation, an inverse pitchfork bifurcation and a Hopf bifurcation. There are symmetric solutions, asymmetric solutions and oscillatory solutions for flows. When the sudden expansion ratio (Er) = 6.00, aspect ratio (Ar) = 1.78 and Re ≤ Rec1 (≈185), the numerical solution is unique, symmetric and stable. When Rec1 < Re ≤ Rec2 (≈213), two stable asymmetric solutions and one symmetric unstable solution are reached. When Rec2 < Re ≤ Rec3 (≈355), the number of numerical solution returns one, which is stable and symmetric. When Re > Rec3, the numerical solution is oscillatory. With increasing Re, the numerical solution develops from periodic and multiple periodic solutions to chaos. The critical Reynolds numbers (Rec1, Rec2 and Rec3) and the maximum return velocity, at which reflux occurs in the channel, change significantly under conditions with different geometry. In this paper, the variation rules of Rec1, Rec2 and Rec3 are investigated, as well as the maximum return velocity with the sudden expansion ratio Er and the aspect ratio Ar.
Geometry of Enumerable Class of Surfaces Associated with Mylar Balloons
Authors: Pulov Vladimir I. , Kovalchuk Vasyl , Mladenov Ivaïlo M.
Published: February 2024

In this paper, the very fundamental geometrical characteristics of the Mylar balloon like the profile curve, height, volume, arclength, surface area, crimping factor, etc. are recognized as geometrical moments In(x) and In and this observation has been used to introduce an infinite family of surfaces Sn specified by the natural numbers n=0,1,2,…. These surfaces are presented via explicit formulas (through the incomplete Euler’s beta function) and can be identified as an interesting family of balloons. Their parameterizations is achieved relying on the well-known relationships among elliptic integrals, beta and gamma functions. The final results are expressed via the fundamental mathematical constants, such as π and the lemniscate constant ϖ. Quite interesting formulas for recursive calculations of various quantities related to associated figures modulo four are derived. The most principal results are summarized in a table, illustrated via a few graphics, and some direct relationships with other fundamental areas in mathematics, physics, and geometry are pointed out.
Current Approach to Risk Factors and Biomarkers of Intestinal Fibrosis in Inflammatory Bowel Disease
Authors: Dudek Patrycja , Talar-Wojnarowska Renata
Published: February 2024

Inflammatory bowel disease (IBD), especially Crohn’s disease (CD), characterized by a chronic inflammatory process and progressive intestinal tissue damage, leads to the unrestrained proliferation of mesenchymal cells and the development of bowel strictures. Complications induced by fibrosis are related to high rates of morbidity and mortality and lead to a substantial number of hospitalizations and surgical procedures, generating high healthcare costs. The development of easily obtained, reliable fibrogenesis biomarkers is essential to provide an important complementary tool to existing diagnostic and prognostic methods in IBD management, guiding decisions on the intensification of pharmacotherapy, proceeding to surgical methods of treatment and monitoring the efficacy of anti-fibrotic therapy in the future. The most promising potential markers of fibrosis include cartilage oligomeric matrix protein (COMP), hepatocyte growth factor activator (HGFA), and fibronectin isoform- extra domain A (ED-A), as well as antibodies against granulocyte macrophage colony-stimulating factor (GM-CSF Ab), cathelicidin (LL-37), or circulatory miRNAs: miR-19a-3p and miR-19b-3p. This review summarizes the role of genetic predisposition, and risk factors and serological markers potentially contributing to the pathophysiology of fibrotic strictures in the course of IBD.
Attitudes of the Lithuanian Population toward COVID-19 Vaccination and Evaluation of Its Effectiveness: A Cross-Sectional Study
Authors: Airapetian Artur , Bachmetjev Benedikt , Zablockis Rolandas
Published: February 2024

Background and Objectives: This study delves into the attitudes, beliefs and determinants influencing the uptake of the COVID-19 vaccine among the Lithuanian population. Materials and Methods: Utilizing a cross-sectional study design, a total of 3166 respondents were surveyed. Results: The findings reveal a significant disparity in vaccination rates based on socio-demographic factors, with higher uptake observed among individuals with a university degree, urban residents and those in higher income brackets. Personal beliefs, particularly regarding the vaccine’s efficacy in pandemic management, played a pivotal role in vaccination decisions. This study also highlights the influence of external factors, such as the activity of the “anti-vaxxer” movement and the introduction of vaccination certificates. Conclusions: The results emphasize the need for targeted educational interventions and comprehensive public health campaigns to address vaccine hesitancy and promote widespread immunization.
Stiffness of Anatomically Shaped Lattice Scaffolds Made by Direct Metal Laser Sintering of Ti-6Al-4V Powder: A Comparison of Two Different Design Variants
Authors: Turudija Rajko , Stojković Miloš , Stojković Jelena R. , Aranđelović Jovan , Marinković Dragan
Published: February 2024

The modern approach to the recovery of damaged and missing bone tissue is increasingly focused on the application of implants capable of supporting the growth and recovery of parent tissue, rather than replacing the tissue itself. In this regard, the primary task of modern bone implants is to enable the targeted deformation of the implant against the expected load that that piece of bone should bear. The paper presents research related to anatomically shaped lattice scaffolds (ASLSs) made by the direct metal laser sintering (DMLS) of Ti-6Al-4V powder, and refers to the influence of the crossing angle between the outer lattice struts on the rigidity of the scaffold structure. The study includes the measurement of the deformation of two ASLSs designed for the same missing piece of rabbit tibia; these differed in terms of the crossing angle of the struts in the outer lattice and were exposed to quasi-uniaxial compression. The results show that the ASLS with outer struts that intersect at 60° (the angle between the compression direction and the strut axes is 30°) is more flexible compared to the ASLS with outer struts that intersect at 90° (the compression direction and the strut axes are colinear), even though its porosity is lower and volume is bigger.
Study on the Optimization of Heat Transfer Coefficient of a Rare Earth Wrought Magnesium Alloy in Residual Stress Analysis
Authors: Xie Qiumin , Wu Yunxin , Wu Yuanzhi , Peng Shunli
Published: February 2024

To investigate the heat transfer coefficient (HTC) of a newly developed rare-earth wrought magnesium alloy under different cooling rates, the experiment of solution treatment followed by water quenching or air cooling process was carried out for calculation by lumped capacitance method (LCM) and optimized by inverse heat transfer method (IHTM), and cooling temperature curves were simulated afterward. In water quenching, the larger the temperature difference between the sample and water, the larger the maximum HTC, and the earlier it reached the maximum value, and in air cooling the HTC became larger with the airflow speeds increased. In LCM, the peak values of the HTC were 2840 W/(m2·°C) in water quenching and 54 W/(m2·°C) in air cooling. The corresponding HTC was 2388 W/(m2·°C) in IHTM. The maximum absolute average relative error (AARE) of temperature simulation in water quenching decreased from 8.46% in LCM to 2.45% in IHTM. The residual stress(RS) of a large conical component was simulated using both non-optimized and optimized HTC, the RS in the IHTM was ~30 MPa smaller than that in the ILCM, because the corresponding HTC was smaller, and the comparison of the simulation results with the measurements revealed that the RS using HTC in the IHTM is more accurate.
Intestinal Dysbiosis in Subjects with Obesity from Western Mexico and Its Association with a Proinflammatory Profile and Disturbances of Folate (B9) and Carbohydrate Metabolism
Authors: Riggen-Bueno Verónica , Del Toro-Arreola Susana , Baltazar-Díaz Tonatiuh Abimael , Vega-Magaña Alejandra N. , Peña-Rodríguez Marcela , Castaño-Jiménez Paula Alejandra , Sánchez-Orozco Laura Verónica , Vera-Cruz José María , Bueno-Topete Miriam Ruth
Published: February 2024

Obesity is a public health problem with a growing prevalence worldwide. In Mexico, it is estimated that one out of three adults suffer from obesity. In these patients, the intestinal microbiota (IM) undergoes pathological changes that are associated with a dysbiotic state; however, the microbiota profile of adult subjects with obesity from western Mexico has not been described. To assess this, fecal samples were obtained from 65 participants (Obese = 38; Control = 27). The microbial composition was characterized by 16S rRNA amplicon sequencing. The IM of the group with obesity revealed a clear decrease in richness and diversity (p < 0.001), as well as a significant increase in proinflammatory bacterial groups, mainly genera belonging to the Negativicutes class, Escherichia/Shigella, and Prevotella. Likewise, an increase in short-chain fatty acid-producing bacteria was found, especially the genus Lachnoclostridium. Additionally, PICRUSt2 analysis showed a depletion of vitamin B9 metabolism and an increase in saccharolytic pathways. The IM of patients with obesity possesses a dysbiotic, proinflammatory environment, possibly contributing to lipogenesis and adiposity. Thus, assessing the IM will allow for a better understanding of the pathophysiology of metabolic diseases of high prevalence, such as obesity. These findings are described for the first time in the adult population of western Mexico.
Multiscale Fabrication Process Optimization of DFB Cavities for Organic Laser Diodes
Authors: Ouirimi Amani , Chime Alex Chamberlain , Loganathan Nixson , Chakaroun Mahmoud , Gaimard Quentin , Fischer Alexis P. A.
Published: February 2024

In the context of the quest for the Organic Laser Diode, we present the multiscale fabrication process optimization of mixed-order distributed-feedback micro-cavities integrated in nanosecond-short electrical pulse-ready organic light-emitting diodes (OLEDs). We combine ultra-short pulsed electrical excitation and laser micro-cavities. This requires the integration of a highly resolved DFB micro-cavity with an OLED stack and with microwave electrodes. In a second challenge, we tune the cavity resonance precisely to the electroluminescence peak of the organic laser gain medium. This requires precise micro-cavity fabrication performed using e-beam lithography to pattern gratings with a precision in the nanometer scale. Optimal DFB micro-cavities are obtained with 300 nm thick hydrogen silsesquioxane negative-tone e-beam resist on 50 nm thin indium tin oxide anode exposed with a charge quantity per area (i.e., dose) of 620 µC/cm2, developed over 40 min in tetramethylammonium hydroxide diluted in water. We show that the integration of the DFB micro-cavity does not hinder the pulsed electrical operability of the device, which exhibits a peak current density as high as 14 kA/cm2.
Enhancing Pixel Charging Efficiency by Optimizing Thin-Film Transistor Dimensions in Gate Driver Circuits for Active-Matrix Liquid Crystal Displays
Authors: Ma Xiaoxin , Zou Xin , Yan Ruoyang , Yeung Fion Sze Yan , Zhang Wanlong , Yuan Xiaocong
Published: February 2024

Flat panel displays are electronic displays that are thin and lightweight, making them ideal for use in a wide range of applications, from televisions and computer monitors to mobile devices and digital signage. The Thin-Film Transistor (TFT) layer is responsible for controlling the amount of light that passes through each pixel and is located behind the liquid crystal layer, enabling precise image control and high-quality display. As one of the important parameters to evaluate the display performance, the faster response time provides more frames in a second, which benefits many high-end applications, such as applications for playing games and watching movies. To further improve the response time, the single-pixel charging efficiency is investigated in this paper by optimizing the TFT dimensions in gate driver circuits in active-matrix liquid crystal displays. The accurate circuit simulation model is developed to minimize the signal’s fall time (Tf) by optimizing the TFT width-to-length ratio. Our results show that using a driving TFT width of 6790 μm and a reset TFT width of 640 μm resulted in a minimum Tf of 2.6572 μs, corresponding to a maximum pixel charging ratio of 90.61275%. These findings demonstrate the effectiveness of our optimization strategy in enhancing pixel charging efficiency and improving display performance.
Optimization of an Alternative Culture Medium for Phycocyanin Production from Arthrospira platensis under Laboratory Conditions
Authors: Freire Balseca Daniel Alberto , Castro Reyes Kimberly Susana , Maldonado Rodríguez María Elena
Published: February 2024

Arthrospira platensis, known as spirulina, is a cyanobacterium with multiple nutritional benefits, as it contains substantial amounts of proteins, fatty acids, and pigments. However, the production of this microalga has faced significant challenges, primarily related to the cost and composition of the required culture medium for its optimal growth. This study focused on optimizing two nitrogen sources (urea and potassium nitrate) to maximize the growth of A. platensis and the production of phycocyanin, a photosynthetic pigment of significant commercial value. Optimization was performed using the response surface methodology (RSM) with a central composite design (CCD). Analysis of variance (ANOVA) was employed to validate the model, which revealed that the different concentrations of urea were statistically significant (p < 0.05) for biomass and phycocyanin production. However, potassium nitrate (KNO3) showed no significant influence (p > 0.05) on the response variables. The RSM analysis indicated that the optimal concentrations of KNO3 and urea to maximize the response variables were 3.5 g L−1 and 0.098 g L−1, respectively. This study offers valuable perspectives for the efficient production of A. platensis while reducing production costs for its cultivation on a larger scale.
Soil Microbes and Plant-Associated Microbes in Response to Radioactive Pollution May Indirectly Affect Plants and Insect Herbivores: Evidence for Indirect Field Effects from Chernobyl and Fukushima
Authors: Sakauchi Ko , Otaki Joji M.
Published: February 2024

The biological impacts of the nuclear accidents in Chernobyl (1986) and Fukushima (2011) on wildlife have been studied in many organisms over decades, mainly from dosimetric perspectives based on laboratory experiments using indicator species. However, ecological perspectives are required to understand indirect field-specific effects among species, which are difficult to evaluate under dosimetric laboratory conditions. From the viewpoint that microbes play a fundamental role in ecosystem function as decomposers and symbionts for plants, we reviewed studies on microbes inhabiting soil and plants in Chernobyl and Fukushima in an attempt to find supporting evidence for indirect field-specific effects on plants and insect herbivores. Compositional changes in soil microbes associated with decreases in abundance and species diversity were reported, especially in heavily contaminated areas of both Chernobyl and Fukushima, which may accompany explosions of radioresistant species. In Chernobyl, the population size of soil microbes remained low for at least 20 years after the accident, and the abundance of plant-associated microbes, which are related to the growth and defense systems of plants, possibly decreased. These reported changes in microbes likely affect soil conditions and alter plant physiology. These microbe-mediated effects may then indirectly affect insect herbivores through food-mass-mediated, pollen-mediated, and metabolite-mediated interactions. Metabolite-mediated interactions may be a major pathway for ecological impacts at low pollution levels and could explain the decreases in insect herbivores in Fukushima. The present review highlights the importance of the indirect field effects of long-term low-dose radiation exposure under complex field circumstances.