bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of Brake Wear Particles on Eukaryotic Cell Viability and Associated Oxidative Stress Responses
Authors: Trečiokaitė Lina , Tsybrii Yurii , Nosko Oleksii , Ragelienė Lina
Published: December 2024

In this study, the cytotoxic effects of brake wear particles (≥250 nm ceramic/ceramic wear particles (CCWPs) and ≤100 nm ceramic/steel wear particles (CSWPs)) and 100 nm iron (III) oxide ultrafine particles (IOUFPs) on human lung carcinoma (A549) and Chinese hamster ovary (CHO) cells were investigated. Cell viability was determined using the MTT and Calcein AM methods. Oxidative stress was assessed by measuring reactive oxygen species (ROS), intracellular reduced glutathione (GSH), and malondialdehyde (MDA) concentrations under exposure to the above particles in the concentration range of 10–80 µg/mL. The initial assessments of CCWPs and CSWPs on the cell viability were performed after a 4-h exposure but later extended to 24 h to investigate the time-dependent of the cell viability and oxidative stress. MTT and Calcein AM assays indicated that the A549 cells are less susceptible to CCWPs and CSWPs than the CHO cells when exposed for both 4 h and 24 h. This study highlights that oxidative stress induced by CCWPs, CSWPs, and IOUFPs is cell-specific. While CCWPs did not affect glutathione (GSH) levels in the CHO cells, it significantly reduced GSH levels in A549 cells, with the exception of 80 µg/mL. Both CCWPs and CSWPs increased the lipid peroxidation in both cell types; however, the A549 cells demonstrated lower sensitivity to these treatments.
Hydrogen Diffusion in Deformed Austenitic TRIP Steel—A Study of Mathematical Prediction and Experimental Validation
Authors: Hempel Christian , Mandel Marcel , Quitzke Caroline , Wendler Marco , Kreschel Thilo , Volkova Olena , Krüger Lutz
Published: December 2024

This study focuses on the effect of pre-deformation on hydrogen diffusion and hydrogen embrittlement of the high alloy austenitic TRIP steel X3CrMnNiMo17-8-4. Different cold-rolled steel sheets with thicknesses of ≤400 µm were electrochemically charged on both sides in 0.1 M sodium hydroxide with hydrogen for two weeks. Comparative measurements on uncharged and immersed samples prove that hydrogen causes embrittlement in this steel for all investigated states. The embrittlement increases with increasing pre-deformation and is accompanied by deformation-induced martensite formation. The corresponding fractured surfaces were examined using electron microscopy and compared to modelled hydrogen distributions with previously determined diffusion coefficients. For this purpose, various diffusion coefficients are determined using the Devanathan–Stachurski permeation test and hot extraction in order to describe the diffusion process. The hydrogen concentration profiles and the fractographic analyses show a good agreement, so this study provides a basis for estimating the embrittlement behaviour for later application.
Utilization of Copper Flotation Tailings in Geopolymer Materials Based on Zeolite and Fly Ash
Authors: Štulović Marija , Radovanović Dragana , Dikić Jelena , Gajić Nataša , Djokić Jovana , Kamberović Željko , Jevtić Sanja
Published: December 2024

Copper flotation tailings (FTs), resulting from the separation and beneficiation processes of ores, are a significant source of environmental pollution (acid mine drainage, toxic elements leaching, and dust generation). The most common disposal method for this industrial waste is dumping. However, due to their favorable physical and chemical properties—the high content of aluminosilicate minerals (60–90%)—flotation tailings can be effectively treated and reused through geopolymerization technology, thereby adding value to this waste. The objective of this study was to evaluate the potential of utilizing the geopolymerization of FTs to produce sustainable materials. Geopolymers based on natural zeolite (NZ), sodium-modified natural zeolite (NaZ), and fly ash (FA) were prepared using 20%, 35%, and 50% of FTs, activated with a 10 M NaOH solution. The study investigated the influence of Ca/Si, Si/Al, and Na/Al molar ratios on the structural, thermal, and mechanical properties (XRD, TG/DTG and unconfined compressive strength, UCS), and contaminant immobilization (TCLP method) of geopolymers. Geochemical modeling via the PHREEQC program was employed to interpret the results. The findings indicated that the UCS value decreased in zeolite-based geopolymers as the content of FT increased due to the inertness of the tailings and the low calcium content in the system (Ca/Si ≤ 0.3), in contrast to the FA-based geopolymer. The highest UCS of 44.3 MPa was recorded in an FA-based geopolymer containing 50% flotation tailings, with optimal molar ratios of 0.4 for Ca/Si, 3.0 for Si/Al, and 1.1 for Na/Al. In conclusion, the geopolymerization process has been determined to be a suitable technological approach for the sustainable treatment and reuse of FTs.
Mechanical Behaviour and Microstructural Analysis of Earthen Materials Reinforced with Intensive Agricultural By-Products and Binders
Authors: Cervilla-Maldonado Ana , Valverde-Palacios Ignacio , Martín-Villegas Francisco , Fuentes-García Raquel
Published: December 2024

Modern construction is largely dependent on steel and concrete, with natural materials such as earth being significantly underutilised. Despite its sustainability and accessibility, earth is not being used to its full potential in developed countries. This study explores innovative building materials using Alhambra Formation soil (Granada, Spain) reinforced with difficult-to-recycle agricultural waste: polypropylene fibres contaminated with organic matter and leachates. Fibres were added at a ratio between 0.20 and 0.80% of the soil mass, leachates at a ratio between 4.25 and 8.50%, and lime was incorporated at 2.00% and 4.00% for specimens with higher residue content. Physico-mechanical properties, including uniaxial compressive strength and longitudinal strain, were analysed together with the microstructure. The results showed that polypropylene fibres, in comparison to the use of leachates, improved compressive strength and ductility, reaching a compressive strength of 1.76 MPa with a fibre content of 0.40%. On the other hand, this value is 7.4% lower than the reference sample without additives. The fibre-reinforced samples showed a higher porosity compared to the samples with leachates or without additives. This approach highlights the potential of agricultural waste for the development of sustainable construction materials, offering enhancements in the strength and ductility of reinforced soils.
Influence of Freeze–Thaw Cycles and Sustained Load on the Durability and Bearing Capacity of Reinforced Concrete Columns
Authors: Chen Chen , Zhang Kai , Ye Lin
Published: December 2024

The deterioration of concrete structures is mainly due to the combined action of the environment and external load. In this study, 32 reinforced concrete columns were prepared to evaluate the coupling actions on the properties of reinforced concrete structures. The durability, bearing capacity, and failure mode of reinforced concrete columns were investigated under the combined action of freeze–thaw (F–T) cycles, sustained load, and salt corrosion (water or composite salt solution). Results show that the mass fluctuation of reinforced concrete columns under a sustained load was more obvious during F-T cycles. During the early F-T cycles, the sustained load was beneficial to the F-T resistance of the reinforced concrete columns. With the increase in F-T cycles, the damage to the columns with a sustained load gradually aggravated. In the composite salt solution, the damage to the reinforced concrete columns was postponed, and its durability showed a two-stage evolution. After 100 F-T cycles, the mass loss and relative dynamic modulus of elasticity (RDME) deterioration of the columns with a sustained load sped up significantly. The combined action of salt corrosion, load, and F-T cycles has the most significant influence on the bearing capacity, stiffness deterioration, and crack development of reinforced concrete columns.
Influence of Flow Control Devices on Mixing Phenomena in the Ladle with Top Lance Stirring System—Numerical and Physical Modeling
Authors: Cwudziński Adam
Published: December 2024

In this paper, the influence of the structure of the bottom of the ladle with ceramic dam or set of dams on the mixing process was assessed, determining the mixing time required to achieve the level of 95% chemical homogenization. The 0.1 scale water model was used for the physical experiments. The numerical simulations were carried out in the Ansys-Fluent 12.1 software for a 1:1 scale ladle and the behavior of hot metal—nitrogen system. The research focused on three issues, i.e., the influence of the flow rate of technical gas, the influence of the position of the top injection lance, and the influence of the type of dam mounted in the ladle bottom. Finally, the use of a semi-circle dam or set of dams in the ladle bottom together with the top lance being set to a lower depth resulted in a significant reduction in the total mixing time of the liquid metal by 42% and 50%, respectively, without increasing the nitrogen flow rate.
Effect of Plate Thickness on the Laser-Welded Microstructure and Mechanical Properties of 22MnB5 Hot-Forming Steel
Authors: Sang Kaixuan , Li Xin , Zhang Yu , Yi Lingling , Chen Jing , Lu Yuting , Gu Zhengwei
Published: December 2024

To meet the development and application needs of advanced high-strength steel, the laser welding of 22MnB5 hot-forming steel plates with thicknesses of 2 mm, 3 mm, and 4 mm was studied in this paper. Mechanical testing revealed that as plate thickness increased, the tensile strength of welded joints decreased from 1489 MPa to 1357 MPa and 1275 MPa, equating to 96%, 91%, and 88% of the corresponding base metal strength, respectively. The heat-affected zone exhibited the lowest mechanical properties. Microstructural characterization showed that with increasing plate thickness, martensite grains in the welded joints grew larger, transitioning from fine acicular to larger island structures. Concurrently, dislocation density in the welded joints decreased gradually. Furthermore, microstructural changes in the heat-affected zone were more pronounced than those in the fusion zone. The larger grain size and reduced dislocation density softened the joint structure, which consequently decreased the strength and hardness of the welded joint. Laser-welded joints of three thicknesses can exceed 85% of the corresponding base metal strength, demonstrating strong industrial application potential.
Fatigue Analysis of Axisymmetric Chiral Cellular Structures Made out of 316L Stainless Steel
Authors: Žnidarič Žiga , Nečemer Branko , Novak Nejc , Glodež Srečko
Published: December 2024

In the proposed study, the fatigue analysis of an axisymmetric chiral cellular structure and its modified form, made of stainless steel 316L, is carried out. The main goal of the original structure geometry was to absorb as much mechanical energy as possible with its auxetic behaviour. However, it was found through testing that its response could be improved by modifying the thickness of the struts through the structure. Representative models for the original and modified geometries were generated using a script adapted for this numerical simulation. Three different types of displacement in the shape of sine waves were used to load the structures. A hexagonal mesh was assigned and determined by convergence analysis. An existing material model with the necessary LCF parameters was assigned in the computational analyses. The data from multiple simulations were recorded and presented in graphs that showed how the fatigue life of the structures changed depending on the level of strain. We also analysed stresses and plastic deformations that occur in the structures. The results showed that, despite a better stress distribution, the fatigue life of the optimised structure was shorter in all cases.
The COVID-19 Mortality Rate in Latin America: A Cross-Country Analysis
Authors: de Araújo Fernando José Monteiro , Guerra Renata Rojas , Peña-Ramírez Fernando Arturo
Published: December 2024

Latin America was one of the hotspots of COVID-19 during the pandemic. Therefore, understanding the COVID-19 mortality rate in Latin America is crucial, as it can help identify at-risk populations and evaluate the quality of healthcare. In an effort to find a more flexible and suitable model, this work formulates a new quantile regression model based on the unit ratio-Weibull (URW) distribution, aiming to identify the factors that explain the COVID-19 mortality rate in Latin America. We define a systematic structure for the two parameters of the distribution: one represents a quantile of the distribution, while the other is a shape parameter. Additionally, some mathematical properties of the new regression model are presented. Point and interval estimates of maximum likelihood in finite samples are evaluated through Monte Carlo simulations. Diagnostic analysis and model selection are also discussed. Finally, an empirical application is presented to understand and quantify the effects of economic, social, demographic, public health, and climatic variables on the COVID-19 mortality rate quantiles in Latin America. The utility of the proposed model is illustrated by comparing it with other widely explored quantile models in the literature, such as Kumaraswamy and unit Weibull regressions.
Exploring Kernel Machines and Support Vector Machines: Principles, Techniques, and Future Directions
Authors: Du Ke-Lin , Jiang Bingchun , Lu Jiabin , Hua Jingyu , Swamy M. N. S.
Published: December 2024

The kernel method is a tool that converts data to a kernel space where operation can be performed. When converted to a high-dimensional feature space by using kernel functions, the data samples are more likely to be linearly separable. Traditional machine learning methods can be extended to the kernel space, such as the radial basis function (RBF) network. As a kernel-based method, support vector machine (SVM) is one of the most popular nonparametric classification methods, and is optimal in terms of computational learning theory. Based on statistical learning theory and the maximum margin principle, SVM attempts to determine an optimal hyperplane by addressing a quadratic programming (QP) problem. Using Vapnik–Chervonenkis dimension theory, SVM maximizes generalization performance by finding the widest classification margin within the feature space. In this paper, kernel machines and SVMs are systematically introduced. We first describe how to turn classical methods into kernel machines, and then give a literature review of existing kernel machines. We then introduce the SVM model, its principles, and various SVM training methods for classification, clustering, and regression. Related topics, including optimizing model architecture, are also discussed. We conclude by outlining future directions for kernel machines and SVMs. This article functions both as a state-of-the-art survey and a tutorial.
The Lichnerowicz-Type Laplacians: Vanishing Theorems for Their Kernels and Estimate Theorems for Their Smallest Eigenvalues
Authors: Mikeš Josef , Stepanov Sergey , Tsyganok Irina
Published: December 2024

In the present paper, we prove several vanishing theorems for the kernel of the Lichnerowicz-type Laplacian and provide estimates for its lowest eigenvalue on closed Riemannian manifolds. As an example of the Lichnerowicz-type Laplacian, we consider the Hodge–de Rham Laplacian acting on forms and ordinary Lichnerowicz Laplacian acting on symmetric tensors. Additionally, we prove vanishing theorems for the null spaces of these Laplacians and find estimates for their lowest eigenvalues on closed Riemannian manifolds with suitably bounded curvature operators of the first kind, sectional and Ricci curvatures. Specifically, we will prove our version of the famous differential sphere theorem, which we will apply to the aforementioned problems concerning the ordinary Lichnerowicz Laplacian.
Dynamics of Chronic Myeloid Leukemia Under Imatinib Treatment: A Study of Resistance Development
Authors: Badralexi Irina , Bordei Ana-Maria , Halanay Andrei , Rădulescu Ileana Rodica
Published: December 2024

Chronic myeloid leukemia (CML) is a hematological disorder characterized by the abnormal proliferation of leukemic cells. This study aims to model the dynamics of leukemic and healthy cell populations in CML, considering the role of the immune system and the effects of treatment with Imatinib. The model also addresses the development of treatment resistance in cells, following the Goldie–Coldman hypothesis. We employ a system of delay differential equations to simulate the interactions between leukemic cells, healthy cells, and the immune system under treatment. The results provide insights into the dynamic balance between leukemic cells, healthy cells, and immune responses, and the impact of developing resistance on treatment outcomes.
Testing Spherical Symmetry Based on Statistical Representative Points
Authors: Liang Jiajuan , He Ping , Liu Qiong
Published: December 2024

This paper introduces a novel chisquare test for spherical symmetry, utilizing statistical representative points. The proposed representative-point-based chisquare statistic is shown, through a Monte Carlo study, to considerably improve the power performance compared to the traditional equiprobable chisquare test in many high-dimensional cases. While the test requires relatively large sample sizes to approximate the chisquare distribution, obtaining critical values from existing chisquare tables is simpler compared to many existing tests for spherical symmetry. A real-data application demonstrates the robustness of the proposed method against different choices of representative points. This paper argues that the use of representative points provides a new perspective in high-dimensional goodness-of-fit testing, offering an alternative approach to evaluating spherical symmetry in such contexts. By leveraging the flexibility of choosing the number of representative points, this method ensures more reliable detection of departures from spherical symmetry, especially in high-dimensional datasets. Overall, this research highlights the practical advantages of the proposed approach in statistical analysis, emphasizing its potential as a powerful tool in goodness-of-fit tests within the realm of high-dimensional data.
Variational Information Principles to Unveil Physical Laws
Authors: Bernal-Casas D. , Oller J. M.
Published: December 2024

This article demonstrates that the application of the variation method to purely information-theoretic models can lead to the discovery of fundamental equations in physics, such as Schrödinger’s equation. Our solution, expressed in terms of information parameters rather than physical quantities, suggests a profound implication—Schrödinger’s equation can be viewed as a unique physical expression of a more profound informational formalism, inspiring new avenues of research.
The Assymptotic Invariants of a Fermat-Type Set of Points in P3
Authors: Le Van Mikołaj , Szemberg Tomasz
Published: December 2024

In this paper, we compute asymptotic invariants—specifically, the Waldschmidt constants and the Seshadri constants—of a set of 31 points in P3, defined as the intersection points of a Fermat-type arrangement of planes.
Analytical Shortcuts to Multiple-Objective Portfolio Optimization: Investigating the Non-Negativeness of Portfolio Weight Vectors of Equality-Constraint-Only Models and Implications for Capital Asset Pricing Models
Authors: Qi Yue , Wang Yue , Huang Jianing , Zhang Yushu
Published: December 2024

Computing optimal-solution sets has long been a topic in multiple-objective optimization. Despite substantial progress, there are still research limitations in the multiple-objective portfolio optimization area. The optimal-solution sets’ structure is barely known. Public-domain software for even three objectives is absent. Alternatively, researchers scrutinize equality-constraint-only models and analytically resolve them. Within this context, this paper extends these analytical methods for nonnegative constraints and thus theoretically contributes to the literature. We prove the existence of positive elements and negative elements for the optimal-solution sets. Practically, we prove that non-negative subsets of the optimal-solution sets can exist. Consequently, the possible existence endorses these analytical methods, because researchers bypass mathematical programming, analytically resolve, and pinpoint some non-negative optima. Moreover, we elucidate these analytical methods’ alignment with capital asset pricing models (CAPMs). Furthermore, we generalize for k-objective models. In conclusion, this paper theoretically reinforces these analytical methods and hints the optimal-solution sets’ structure for multiple-objective portfolio optimization.
A Dynamic Hill Cipher with Arnold Scrambling Technique for Medical Images Encryption
Authors: Xi Yuzhou , Ning Yu , Jin Jie , Yu Fei
Published: December 2024

Cryptography is one of the most important branches of information security. Cryptography ensures secure communication and data privacy, and it has been increasingly applied in healthcare and related areas. As a significant cryptographic method, the Hill cipher has attracted significant attention from experts and scholars. To enhance the security of the traditional Hill cipher (THC) and expand its application in medical image encryption, a novel dynamic Hill cipher with Arnold scrambling technique (DHCAST) is proposed in this work. Unlike the THC, the proposed DHCAST uses a time-varying matrix as its secret key, which greatly increases the security of the THC, and the new DHCAST is successfully applied in medical images encryption. In addition, the new DHCAST method employs the Zeroing Neural Network (ZNN) in its decryption to find the time-varying inversion key matrix (TVIKM). In order to enhance the efficiency of the ZNN for solving the TVIKM, a new fuzzy zeroing neural network (NFZNN) model is constructed, and the convergence and robustness of the NFZNN model are validated by both theoretical analysis and experiment results. Simulation experiments show that the convergence time of the NFZNN model is about 0.05 s, while the convergence time of the traditional Zeroing Neural Network (TZNN) model is about 2 s, which means that the convergence speed of the NFZNN model is about 400 times that of the TZNN model. Moreover, the Peak Signal to Noise Ratio (PSNR) and Number of Pixel Change Rate (NPCR) of the proposed DHCAST algorithm reach 9.51 and 99.74%, respectively, which effectively validates its excellent encryption quality and attack prevention ability.
Effect of Foot Insole on Planter Pressure Distribution in Patients with Neuropathic Diabetic Foot Ulcer: A Prospective, Randomized, Double-Blinded, Controlled Clinical Trial
Authors: Elgohary Hany M. , Allam Ibtsam , Tolba Ahmed M. N. , Ali Faten , Alwhaibi Reem M. , Zakaria Hoda M. , Ragab Walaa M. , Elbalawy Youssef
Published: December 2024

Background and Objectives: Patients with diabetes polyneuropathy are at a heightened risk for developing foot ulcers, often due to dynamic plantar foot pressure patterns that lead to increased pressure and shear forces in specific foot areas. This study aimed to evaluate the effects of foot insoles on peak pressure and the pressure–time integral in patients with polyneuropathy diabetic foot ulcers over a twelve-week period followed by an eight-week follow up. Materials and Methods: This was a prospective, randomized, double-blinded, controlled clinical trial involving 60 patients aged between 50 and 65 years of both genders. Inclusion criteria included midfoot ulcer grades II or III, a history of polyneuropathy diabetic foot ulcers lasting between six months and one year, diabetes duration of seven to ten years, glycated hemoglobin levels between 7% and 9%, and a body mass index (BMI) ranging from 25 to 30 kg/m2. Participants were randomly assigned to either the study group, which received foot insoles along with medication and wound care, or the control group, which received only medication and wound care. Measurements of peak pressure and pressure–time integrals were taken at the start of this study, after twelve weeks, and again eight weeks post-study. Results: The results indicated significant differences in peak pressure and pressure–time integral measurements for the rearfoot, midfoot, hallux, and both medial and lateral forefoot areas after twelve weeks of using foot insoles compared to the control group. This suggests that the use of foot insoles effectively reduces peak pressure and the pressure–time integral in these critical areas. Conclusions: The findings of this study support the use of foot insoles as a beneficial intervention for decreasing peak pressure and the pressure–time integral on the hallux, medial, and lateral forefoot in patients with polyneuropathic diabetic foot ulcers, and they could play a crucial role in preventing further complications.
Effect of Precipitates on Dislocation Loops in Vanadium Alloy After Irradiation with 60 keV Deuterium Ions at Room Temperature
Authors: Wang Jing , Chen Mingxin , Zhang Yifan , Ma Bing , Jiang Haiyan , Chen Chang
Published: December 2024

The effect of different precipitates and nanoparticles on the distribution of radiation-induced dislocation loops in V-4Cr-4Ti alloy and V-4Cr-4Ti-1.8Y-0.4Ti3SiC2 alloy were studied. Both alloys were irradiated with 60 keV deuterium, and the distribution of the dislocation loops was statistically analyzed using the transmission electron microscope (TEM) technique. The results indicated that platelet-like Ti(CNO) precipitates affect the dislocation distribution, in which a significantly reduced dislocation number density in the area within 20 nm of the interface was observed. This phenomenon is attributed to the strong compressive strain in the vertical interface direction at the precipitates/matrix interface. No significant effect on loop distribution was observed in the coherent TiC/matrix interface, which may result from the almost no strain interface. In addition, the uniform distribution of radiation-induced dislocation loops in equivalent crystal orientation was confirmed via the TEM images with multiple g vectors.
Corrosion Inhibition of Carbon Steel Immersed in Standardized Reconstituted Geothermal Water and Individually Treated with Four New Biosourced Oxazoline Molecules
Authors: Helali Chahinez , Betelu Stephanie , Valentin Romain , Thiebaud-Roux Sophie , Ignatiadis Ioannis
Published: December 2024

The current demand for heat production via geothermal energy is increasingly rising amid concerns surrounding non-renewable forms of energy. The Dogger aquifer in the Paris Basin (DAPB) in France produces saline geothermal waters (GWs), which are as hot as 70–85 °C, anaerobic, slightly acidic (pH 6.1–6.4), and characterized mainly by the presence of Cl−, SO42−, CO2/HCO3−, and H2S/HS−. These GWs are corrosive, and the casings of all geothermal wells are carbon steel. Since 1989, these GWs have been progressively treated using petrosourced organic corrosion inhibitors (PS–OCI) at the bottom of the production wells. Currently, there is a great need to test not only new PS–OCIs but also, and above all, biosourced organic corrosion inhibitors (BS–OCIs) to improve the efficiency and environmental friendliness of this carbon-free geothermal energy source. The main objective of this study is to evaluate the potential performance of biosourced corrosion inhibitor candidates (BS–CICs) in terms of their inhibition efficiency (IE) for carbon steel corrosion. This was achieved using a previously established geochemical and electrochemical method to study the mechanisms and kinetics of the corrosion/scaling of carbon steel and optimize short-term corrosion inhibition in standardized reconstituted geothermal water (SRGW) representative of the DAPB’s waters. Four new molecules from the 2-oxazoline family were evaluated individually and compared based on their behavior and inhibition efficiency. These molecules exhibited a mixed nature (i.e., anodic and cathodic inhibitors), with a slight anodic predominance, and showed a significant IE at a concentration of at 10 mg/L during the first hours of immersion of CS-XC38 in SRGW. The average IEs, obtained via the three electrochemical techniques used for the determination of corrosion current densities, i.e., Jcorr(Rp), Jcorr(Tafel), and Jcorr(Rw), are 51%, 79%, 96%, and 93% for Decenox (C10:1), Decanox (C10:0), Undecanox (C11:0), and Tridecanox (C13:0), respectively.
The Relationship Between Maternal Exposure to Endocrine-Disrupting Chemicals and the Incidence of Congenital Heart Diseases: A Systematic Review and Meta-Analysis
Authors: Elhassan Yasir Hassan , Alahmadi Fahad , Albadawi Emad Ali , Albarakati Abdullah , Aljohany Azizah Hendi , Alzaman Naweed SyedKhaleel , Albadrani Muayad
Published: December 2024

Background: Congenital heart diseases are among the most common birth defects, significantly impacting infant health. Recent evidence suggests that exposure to endocrine-disrupting chemicals may contribute to the incidence of congenital heart diseases. This study systematically reviews and analyzes the association between maternal endocrine-disrupting chemicals exposure and congenital heart diseases. Methodology: This systematic review and meta-analysis followed the Cochrane Handbook and PRISMA guidelines. We included studies assessing the link between maternal exposure to various endocrine-disrupting chemicals and the incidence of congenital heart diseases without restricting the study design or exposure assessment methods. Data were extracted from four databases, including PubMed, Scopus, Web of Science, and Cochrane Library, up to June 2024. Quality assessment of observational studies was conducted using the Newcastle–Ottawa Scale. Statistical analysis was performed using RevMan software version 5.3, presenting results as odds ratios with 95% confidence intervals. Results: Fifty-nine studies were included in the meta-analysis. The pooled analysis revealed a significant association between maternal endocrine-disrupting chemical exposure and the incidence of congenital heart diseases when measured using human samples (odds ratio = 1.63, 95% confidence interval [1.35–1.97], p < 0.00001). Notably, exposure to heavy metals, polycyclic aromatic hydrocarbons, and perfluoroalkyl compounds was strongly associated with congenital heart diseases. However, non-sample-based methods showed no significant overall correlation (odds ratio = 1.08, 95% confidence interval [0.93–1.26], p = 0.30), except for housing renovation compounds, which were linked to a higher incidence of congenital heart diseases. Conclusions: Maternal exposure to specific endocrine-disrupting chemicals, particularly heavy metals and polycyclic aromatic hydrocarbons, significantly increases the risk of congenital heart diseases. These findings underscore the need for preventive measures to reduce endocrine-disrupting chemicals exposure during pregnancy and further research to elucidate the underlying mechanisms.
Study on the Carrier Transport Process in Deep Ultraviolet Light-Emitting Diodes with Al-Content-Varied AlGaN Composite Last Quantum Barrier
Authors: Liu Wei , Liu Yujia , Gao Junhua , Liu Zeyu , Shi Bohan , Zhang Linyuan , Zhao Xinnan , Wang Runzhi
Published: December 2024

Serious electron leakage and poor hole injection efficiency are still challenges for deep ultraviolet AlGaN-based light-emitting diodes with a traditional structure in achieving high performance. Currently, the majority of research works concentrate on optimizing the structures of the electron blocking layer (EBL) and last quantum barrier (LQB) separately, rather than considering them as an integrated structure. Therefore, in this study, an Al-content-varied AlGaN composite last quantum barrier (CLQB) layer is proposed to replace the traditional EBL and LQB layers. It is found that when the Al content in the CLQB decreases from 70% to 60% along the growth direction, the sample’s luminescence efficiency is improved, which can be ascribed to the higher carrier concentration in the multiple quantum well active region caused by suppressed electron leakage and enhanced hole injection. Additionally, in the CLQB structure, the carrier loss at the EBL/LQB hetero-interface, which is inevitable in the traditional structure, can be avoided. However, if the Al content in the CLQB changes in an opposite way, i.e., increasing from 60% to 70%, the device optoelectronic performance deteriorates, since the electron leakage is enhanced and the hole injection is suppressed.
COVID-19 in Relation to Chronic Antihistamine Prescription
Authors: Puigdellívol-Sánchez Anna , Juanes-González Marta , Calderón-Valdiviezo Ana , Losa-Puig Helena , Valls-Foix Roger , González-Salvador Marta , Lozano-Paz Celia , Vidal-Alaball Josep
Published: December 2024

No hospitalizations or deaths occurred in residents with the COVID-19 infection, treated with antihistamines and azithromycin, of two external nursing homes during the first wave. We assessed whether patients receiving chronic antihistamines in our institution showed better clinical evolution. COVID-19 admissions and related deaths in the public Hospital of Terrassa (n = 1461) during the pandemic period (11 March 2020–5 May 2023) and cases (n = 32,888) during the period of full suspicion diagnosis (1 June 2020–23 March 2022) were referred to as the number of chronic treatments (nT) including or not including antihistamines (AntiHm or NOAntiHm), and their vaccination status before the first infection (VAC or NoVAC) in our assigned population (n = 140,681 at March 2020) was recorded. No deaths occurred in patients treated with up to ≤6 nT in the AntiHm group in all ages. A significant reduction in hospital admission was observed in the 2–7 nT groups either below or over 60 years old [Odds Ratio (OR) NoAntiHm/AntiHm = 1.76–1.32, respectively, in NoVAC or VAC (OR = 2.10 overall] and in the older ≥8 nT group (OR = 2.08 in NoVac]. In conclusion, patients with chronic antihistamine prescriptions, alone or with polypharmacy, showed reduced hospital admission and mortality rates, suggesting the safety of antihistamine treatment and the need to confirm its effectiveness in a prospective trial.
Antigenic Imprinting Dominates Humoral Responses to New Variants of SARS-CoV-2 in a Hamster Model of COVID-19
Authors: Degryse Joran , Maas Elke , Lassaunière Ria , Geerts Katrien , Kumpanenko Yana , Weynand Birgit , Maes Piet , Neyts Johan , Thibaut Hendrik Jan , Alpizar Yeranddy A. , Dallmeier Kai
Published: December 2024

The emergence of SARS-CoV-2 variants escaping immunity challenges the efficacy of current vaccines. Here, we investigated humoral recall responses and vaccine-mediated protection in Syrian hamsters immunized with the third-generation Comirnaty® Omicron XBB.1.5-adapted COVID-19 mRNA vaccine, followed by infection with either antigenically closely (EG.5.1) or distantly related (JN.1) Omicron subvariants. Vaccination with the YF17D vector encoding a modified Gamma spike (YF-S0*) served as a control for SARS-CoV-2 immunity restricted to pre-Omicron variants. Our results show that both Comirnaty® XBB.1.5 and YF-S0* induce robust, however, poorly cross-reactive, neutralizing antibody (nAb) responses. In either case, total antibody and nAb levels increased following infection. Intriguingly, the specificity of these boosted nAbs did not match the respective challenge virus, but was skewed towards the primary antigen used for immunization, suggesting a marked impact of antigenic imprinting, confirmed by antigenic cartography. Furthermore, limited cross-reactivity and rapid decline in nAbs induced by Comirnaty® XBB.1.5 with EG.5.1 and, more concerning, JN.1, raises doubts about sustained vaccine efficacy against recent circulating Omicron subvariants. In conclusion, we demonstrate that antigenic imprinting plays a dominant role in shaping humoral immunity against emerging SARS-CoV-2 variants. Future vaccine design may have to address two major issues: (i) overcoming original antigenic sin that limits the breadth of a protective response towards emerging variants, and (ii) achieving sustained immunity that lasts for at least one season.
Effects of Distiller’s Grains Biochar and Lactobacillus plantarum on the Remediation of Cd-Pb-Zn-Contaminated Soil and Growth of Sorghum-Sudangrass
Authors: Zhu Guangxu , Li Yufeng , Cheng Dandan , Chen Rongkun , Wang Yunyan , Tu Qiang
Published: December 2024

Soil contamination with heavy metals is a significant environmental issue that adversely affects plant growth and agricultural productivity. Biochar and microbial inoculants have emerged as a promising approach to solving this problem, and previous studies have focused more on the remediation effects of single types of materials on heavy metal soil pollution. This study examined the impact of both standalone and combined applications of distiller’s grains biochar, Lactobacillus plantarum thallus, and the bacterial supernatant on the availability of cadmium (Cd), lead (Pb), and zinc (Zn) in soil, its physicochemical features, and its enzyme activities; this study also examined the growth, physiological and biochemical characteristics, and heavy metal accumulation of Sorghum-sudangrass. The findings suggest that the application of distiller’s grains biochar, Lactobacillus plantarum thallus, and the bacterial supernatant can improve the soil’s physical and chemical properties and enhance soil enzyme activity while reducing the availability of heavy metals in the soil. Furthermore, the addition of these materials promoted plant growth, increased stress resistance, and significantly decreased the accumulation of heavy metals in the plants. A thorough analysis of the results shows that applying 0.025% Lactobacillus plantarum thallus along with 4.4% distiller’s grains biochar produced the best results.
Transcriptome of Kurthia gibsonii TYL-A1 Revealed the Biotransformation Mechanism of Tylosin
Authors: Wang Ye , Zhao Cuizhu , Zhao Boyu , Duan Xinran , Hao Peng , Liang Xiaojun , Yang Lianyu , Gao Yunhang
Published: December 2024

Tylosin (TYL) pollution has aroused widespread concern, and its existence poses a serious threat to the environment and human health. Microbial degradation of antibiotics is considered to be an effective strategy to reduce the environmental impact of antibiotics, but its degradation mechanism is still unclear. In this study, transcriptome analysis was combined to explore the response mechanism of K. gibsonii strain TYL-A1 under TYL stress. The results showed that the strain showed a significant antioxidant response under TYL stress to cope with TYL-induced cell damage. TYL also increased the level of intracellular reactive oxygen species (ROS), damaged the integrity of the cell membrane, and inhibited the growth of strain TYL-A1. Transcriptome sequencing showed that under TYL exposure conditions, 1650 DEGs in strain TYL-A1 showed expression changes, of which 806 genes were significantly up-regulated and 844 genes were significantly down-regulated. Differentially expressed DEGs were significantly enriched in pathways related to metabolism, biosynthesis, and stress response, and tricarboxylic acid cycle, oxidative phosphorylation, and carbon metabolism genes were significantly up-regulated. In conclusion, this study provides novel insights regarding the degradation of TYL by K. gibsonii TYL-A1.
Discordant β-Lactam Susceptibility in Clinical Staphylococcus aureus Isolates: A Molecular and Phenotypical Exploration to Detect the BORSA/MODSA Isolates in Bogotá, Colombia
Authors: Fonseca-Fernández Angie , Mancera-García María , Leal-Castro Aura , Leidy Chad , Rincón Sandra , Carvajal Lina , Reyes Jinnethe , Ramírez Adriana
Published: December 2024

Staphylococcus aureus is a human pathogen responsible for a wide range of diseases, such as skin and soft tissue infections, pneumonia, toxic shock syndrome, and urinary tract infections. Methicillin-resistant S. aureus (MRSA) is a well-known pathogen with consistently high mortality rates. Detecting the mecA resistance gene and phenotypical profile to β-lactams allows for the differentiation of MRSA from methicillin-susceptible S. aureus (MSSA) isolates. In this study, we characterized 57 S. aureus clinical isolates for β-lactam susceptibility and mecA presence. We classified 52.63% as MRSA and 45.61% as MSSA. However, some isolates evidenced different oxacillin resistance profiles, such as borderline oxacillin-resistant or modified S. aureus (BORSA/MODSA). The cefazolin inoculum effect (CzIE) was established for these samples, emphasizing the relevance of these isolates as a source of therapeutic failure. We also performed the detection of the Panton-Valentine Leucocidin virulence genes as well as the S. aureus spa-type clonality. As expected, spa-types t002 and t008 were the most prevalent clones, demonstrating the success of well-established clones. These findings emphasize the importance of establishing sensitivity profiles, especially in isolates with poor resistance mechanisms, to determine their prevalence and their impact on public health.
Complete Genome Sequence of a Novel Azospirillum Strain TA Isolated from Western Siberia Chernevaya Taiga Soil
Authors: Rayko Mikhail , Kravchenko Irina , Lapidus Alla
Published: December 2024

A whole genome sequence of a new strain of the nitrogen-fixing bacterium Azospirillum doebereinerae, known for its diverse plant growth-promoting bacteria (PGPB), was obtained for the first time. The strain, designated Azospirillum doebereinerae AT, was isolated during a soil analysis in the Chernevaya taiga of Western Siberia, a unique and fertile forest ecosystem known for its diverse plant growth-promoting bacteria (PGPB). The A. doebereinerae genome under study is fully assembled into seven circular molecules, none of which are unequivocally plasmids, with a total length of 6.94 Mb and a G + C content of 68.66%. A detailed phylogenomic analysis confirmed its placement within the genus Azospirillum, specifically closely related to A. doebereinerae GSF71T. Functional annotation revealed genes involved in nitrogen metabolism, highlighting the potential of strain TA as a biofertilizer and plant growth-promoting agent. The findings contribute to our understanding of the genomic diversity and metabolic potential of the Azospirillum genus, and they are of interest for further study in the field of comparative bacterial genomics, given the strain’s multi-chromosomal genome structure.
Antiproliferative and Morphological Analysis Triggered by Drugs Contained in the Medicines for Malaria Venture COVID-Box Against Toxoplasma gondii Tachyzoites
Authors: Costa Andréia Luiza Oliveira , dos Santos Mike , Dantas-Vieira Giulia Caroline , Lopes Rosálida Estevam Nazar , Vommaro Rossiane Claudia , Martins-Duarte Érica S.
Published: December 2024

Toxoplasma gondii is a protozoan, and the etiologic agent of toxoplasmosis, a disease that causes high mortality in immunocompromised individuals and newborns. Despite the medical importance of toxoplasmosis, few drugs, which are associated with side effects and parasite resistance, are available for its treatment. Here, we show a screening of molecules present in COVID-Box to discover new hits with anti-T. gondii activity. COVID-Box contains 160 molecules with known or predicted activity against SARS-CoV-2. Our analysis selected 23 COVID-Box molecules that can inhibit the tachyzoite forms of the RH strain of T. gondii in vitro by more than 70% at 1 µM after seven days of treatment. The inhibitory curves showed that most of these molecules inhibited the proliferation of tachyzoites with IC50 values below 0.80 µM; Cycloheximide and (-)-anisomycin were the most active drugs, with IC50 values of 0.02 μM. Cell viability assays showed that the compounds are not toxic at active concentrations, and most are highly selective for parasites. Overall, all 23 compounds were selective, and for two of them (apilimod and midostaurin), this is the first report of activity against T. gondii. To better understand the effect of the drugs, we analyzed the effect of nine of them on the ultrastructure of T. gondii using transmission electron microscopy. After treatment with the selected drugs, the main changes observed in parasite morphology were the arrestment of cell division and organelle alterations.
Whole-Genome Profiling of Endophytic Strain B.L.Ns.14 from Nigella sativa Reveals Potential for Agricultural Bioenhancement
Authors: Douka Dimitra , Spantidos Tasos-Nektarios , Tsalgatidou Polina C. , Katinakis Panagiotis , Venieraki Anastasia
Published: December 2024

Endophytic microbes in medicinal plants often possess beneficial traits for plant health. This study focuses on the bacterial endophyte strain B.L.Ns.14, isolated from Nigella sativa leaves, which demonstrated multiple plant growth-promoting properties. In vitro tests showed that B.L.Ns.14 supports plant growth, colonization, and tolerance to abiotic stress. The strain also exhibited antifungal activity against phytopathogens such as Rhizoctonia solani, Colletotrichum acutatum, Verticillium dahliae, and Fusarium oxysporum f. sp. radicis-lycopersici. Whole-genome analysis, supported by ANI and dDDH values, identified B.L.Ns.14 as Bacillus halotolerans. Genome mining revealed 128 active carbohydrate enzymes (Cazymes) related to endophytism and biocontrol functions, along with genes involved in phosphate solubilization, siderophore and IAA production, biofilm formation, and motility. Furthermore, genes for osmolyte metabolism, Na+/H+ antiporters, and stress response proteins were also identified. The genome harbors 12 secondary metabolite biosynthetic gene clusters, including those for surfactin, plipastatin mojavensin, rhizocticin A, and bacilysin, known for their antagonistic effects against fungi. Additionally, B.L.Ns.14 promoted Arabidopsis thaliana growth under both normal and saline conditions, and enhanced Solanum lycopersicum growth via seed biopriming and root irrigation. These findings suggest that Bacillus halotolerans B.L.Ns.14 holds potential as a biocontrol and plant productivity agent, warranting further field testing.
Vibrational and DFT Studies and Anticancer Activity of Novel Pd(II) and Pt(II) Complexes with Chloro Derivatives of 7-Azaindole-3-Carbaldehyde
Authors: Szmigiel-Bakalarz Ksenia , Kłopotowska Dagmara , Wietrzyk Joanna , Malik Magdalena , Morzyk-Ociepa Barbara
Published: December 2024

This study investigates the structural, vibrational, and biological properties of novel palladium(II) and platinum(II) complexes with 5-chloro-7-azaindole-3-carbaldehyde (5ClL) and 4-chloro-7-azaindole-3-carbaldehyde (4ClL) ligands. Infrared and Raman spectroscopy, combined with DFT (ωB97X-D) calculations, provided valuable information about metal–ligand interactions, the cis or trans conformation of the aldehyde group in the ligands, and the presence of trans isomers in the metal complexes obtained in the solid state. In vitro tests were used to evaluate the antiproliferative activity of the novel complexes against several cancer cell lines, including ovarian cancer (A2780), cisplatin-resistant ovarian cancer (A2780cis), colon cancer (HT-29), and triple-negative breast cancer (MDA-MB-231), as well as normal mouse fibroblasts (BALB/3T3). The platinum complex, trans-[PtCl2(5ClL)2], exhibited superior activity against A2780cis (IC50 = 4.96 ± 0.49 µM) and MDA-MB-231 (IC50 = 4.83 ± 0.38 µM) compared to cisplatin, while the palladium complexes (trans-[PdCl2(4ClL)2] and trans-[PdCl2(5ClL)2]) demonstrated enhanced selectivity with reduced toxicity to normal fibroblasts (IC50 = 11.29 ± 6.65 µM and 14.98 ± 5.59 µM, respectively).