bluuebunny/crossref_metadata_2025 huggingface dataset:
Hybrid Torque Coefficient Control of Average-to-Peak Ratio for Turbine Angular Velocity Reduction in Oscillating-Water-Column-Type Wave Energy Converter
Authors: Chae Hyeongyo , Roh Chan
Published: June 2024

Wave energy converters (WECs) have significant potential to meet the increasing energy demands and using an oscillating water column (OWC) is one of the most reliable ways to implement them. The OWC has a simple structure and excellent durability. However, control of the power take-off (PTO) system is difficult due to variability in the input wave energy. In particular, the design and control of the PTO system are complex, as the average-to-peak ratio of the output generation is large. Owing to the nature of the OWC, if the energy above the rating cannot be controlled, the power generated is inevitably reduced due to the decrease in operating time. We propose a method to reduce the angular speed of the turbine by dividing the section according to the input energy and correspondingly changing the torque coefficient, thereby increasing the operating time of the OWC. The control methods for the PTO system of OWC are verified through a 30 kW full-scale experimental device to be installed in a real sea area. The full-scale experimental device consists of an inverter that simulates the mechanical torque of an OWC based on the aerodynamic simulation of an impulse turbine, an induction motor, a permanent magnet synchronous generator, an AC/DC converter, and a battery for the energy storage system. The performance of conventional control methods and the proposed method are compared based on the results of numerical simulations and experiments. We show that the fluctuation in the turbine angular velocity in the proposed method is significantly reduced compared with that in the conventional control methods under regular and irregular wave conditions.
The Specific and Total CO2 Emission Activity of Wood-Decaying Fungi and Their Response to Increases in Temperature
Authors: Mukhin Victor A. , Diyarova Daria K. , Zhuykova Elena V.
Published: June 2024

The CO2 emission activity of xylotrophic fungi responding to an increase in temperature in the range of 10–30 °C with pure dikaryotic cultures of Fomes fomentarius s. str., F. inzengae, Fomitopsis betulina, F. pinicola, and Phellinus igniarius was analyzed. Emission activity was assessed by the difference in CO2 concentration in 0.5 L exposure chambers with Petri dishes with mycelium growing on agar at the beginning of exposure and an hour later using a Gasmet DX-4030 FTIR spectrometer (Gasmet Technologies Oy, Finland), error measurements ±50 ppm. Specific (μg CO2/cm2/h) and total (μg CO2/h) emission activity and its relationship with temperature and size (area) of the mycelium were assessed. It is shown that in the range of 10–30 °C, the specific and total CO2 emission activity of the mycelium is closely and positively related to temperature. Specific emission, which is an indicator of the respiratory activity of the mycelium, does not depend on its size; its only driver is temperature, the relationship with which is linear: an increase in temperature by 10 °C causes an increase in the specific emission activity of the mycelium by 1.7 times. The total CO2 emission activity, which is an indicator of the total amount of CO2 emitted, is directly proportional to the specific emission activity and the size of the mycelium. In the range of 10–30 °C, an increase in temperature causes an almost equal increase in both the specific emission activity of the mycelium (Q10 1.7) and its growth (Q10 1.5) and causes an exponential increase in the total emission of CO2. This must be taken into account when predicting CO2 emissions from woody debris under climate change, as it could potentially contribute to accelerating climate change.
Composition Profiles at the Metal Substrate–Deposit Interface Produced in Laser-Assisted Additive Manufacturing Processes
Authors: Péter László , Kugler Szilvia , Kolonits Tamás , Nagy Attila
Published: June 2024

The cross-section of various substrate–deposit metal pairs obtained with a laser-assisted additive manufacturing process has been studied by observing the composition profile with energy-dispersive spectroscopy (EDS). The EDS composition profiles observed with a sufficiently high data acquisition time revealed that the composition profile is asymmetric. By scanning toward the growth direction, a sudden composition variation was observed, which was followed by a slow decay. The character of the composition profile was the same for a number of substrate–deposit pairs, and similar trends were found in various earlier publications as well. A mathematical model for the composition variation is suggested based on the assumption that a spontaneous homogenization process takes place in the intermixing (dilution) zone of the remelted top layer of the substrate. The equation obtained makes it possible to quantitatively describe the composition profile of each component that exhibits a concentration difference between the substrate and the deposit, provided that the mole fraction difference much exceeds the scattering of the data measured. The suggested model has also been applied successfully to composition profiles published in other works, hence exhibiting general relevance. Since the variation in some physical parameters (such as hardness) along the growth direction has been reported to follow the same pattern, it is assumed that the root cause in these cases may also be the composition variation.
Vat Photopolymerization of Ceramic Parts: Effects of Carbon Fiber Additives on Microstructure and Mechanical Performance
Authors: Wang Lu , Wu Hailong , Guo Anfu , Kong Dekun , Zhao Zhengyu , Liu Chang , Yin Lvfa , Xia Guojun , Su Xiaofei , Chen Zhong , Wang Diangang
Published: June 2024

Vat photopolymerization (VPP), as an additive manufacturing (AM) technology, can conveniently produce ceramic parts with high resolution and excellent surface quality. However, due to the inherent brittleness and low toughness of ceramic materials, manufacturing defect-free ceramic parts remains a challenge. Many researchers have attempted to use carbon fibers as additives to enhance the performance of ceramic parts, but these methods are mostly applied in processes like fused deposition modeling and hot pressing. To date, no one has applied them to VPP-based AM technology. This is mainly because the black carbon fibers reduce laser penetration, making it difficult to cure the ceramic slurry and thus challenging to produce qualified ceramic parts. To address this issue, our study has strictly controlled the amount of carbon fibers by incorporating trace amounts of carbon fiber powder into the original ceramic slurry with the aim to investigate the impact of these additions on the performance of ceramic parts. In this study, ceramic slurries with three different carbon fiber contents (0 wt.%, 0.1 wt.%, 0.2 wt.%, and 0.3 wt.%) were used for additive manufacturing. A detailed comparative analysis of the microstructure, physical properties, and mechanical performance of the parts was conducted. The experimental results indicate that the 3D-printed alumina parts with added carbon fibers show varying degrees of improvement in multiple performance parameters. Notably, the samples prepared with 0.2 wt.% carbon fiber content exhibited the most significant performance enhancements.
Glass-Forming Ability, Mechanical Properties, and Energetic Characteristics of ZrCuNiAlNbHfY Bulk Metallic Glasses
Authors: Yu Xin , Li Jianbin , Zhang Kaichuang , Zhang Huijie , Wang Hao , Fang Yuanhang , Ma Yusong , Wang Zhenxiong , Zhang Xinggao , Gai Xiqiang
Published: June 2024

The effects of partially substituting Al for Cu in Zr59.62Cu18.4-xNi12Al6+xNb3Hf0.78Y0.2 (x = 0, 2, 4, 6, 8 at.%) bulk metallic glasses (BMGs) on their glass-forming ability (GFA), quasi-static and dynamic mechanical properties, and energy characteristics were investigated. The results showed that an appropriate substitution of Al for Cu can improve GFA and reach a critical casting size up to 10 mm. Additionally, with Al replacement of Cu, the change in the distribution and content of free volume inside the BMGs was the main reason for the quasi-static compression plasticity. In contrast, the BMGs exhibited no plasticity during dynamic compression and high-speed impact, owing to the short loading time and thermal softening effect. In terms of energy characteristics, all alloys have a high combustion enthalpy. And on the surface of the fragments collected from impact, the active elements Zr, Al, and Nb reacted because of the adiabatic temperature rise. Further, x = 4 at.% Zr-based BMG with its superior overall performance could penetrate a 6 mm Q235 plate at a speed of 1038 m/s, combining excellent mechanical properties and energy characteristics. This study contributes to the development of Zr-based BMGs as novel energetic structural materials.
Adaptive Control for Suspension System of In-Wheel Motor Vehicle with Magnetorheological Damper
Authors: Yoon Dal-Seong , Choi Seung-Bok
Published: June 2024

This study proposes two adaptive controllers and applies them to the vibration control of an in-wheel motor vehicle’s (electric vehicle) suspension system, in which a semi-active magnetorheological (MR) damper is installed as an actuator. As a suspension model, a nonlinear quarter car is used, providing greater practical feasibility than linear models. In the synthesis of the controller design, the values of the sprung mass, damping coefficient and suspension stiffness are treated as bounded uncertainties. To take into account the uncertainties, both direct and indirect adaptive sliding mode controllers are designed, in which the principal control parameters for the adaptation law are updated using the auto-tune method. To reflect the practical implementation of the proposed controller, only two accelerometers are used, and the rest of the state values are estimated using a Kalman observer. The designed controller is applied to a quarter car suspension model of an in-wheel motor vehicle featuring an MR damper, followed by a performance evaluation considering factors such as ride comfort and road holding. It is demonstrated in this comparative work that the proposed adaptive controllers show superior control performance to the conventional proportional–integral–derivative (PID) controller by reducing the vibration magnitude by 50% and 70% for the first and second modes, respectively. In addition, it is identified that the second mode (wheel mode) of the in-wheel motor vehicle is more sensitive than the first body mode depending on the mass ratio between the sprung and unsprung mass.
A Study on the Machinability and Environmental Effects of Milling AISI 5140 Steel in Sustainable Cutting Environments
Authors: Zerooğlu Tufan , Değirmenci Ünal , Şap Serhat
Published: June 2024

AISI 5140 steel is an alloy frequently used in the manufacturing and automotive industries. This steel alloy is shaped using different manufacturing methods and cooling is required during this process. This research study included the milling of AISI 5140 steel utilizing various cutting settings and cooling/lubrication procedures. For this purpose, two cutting speeds (75–100 m/min), two feed rates (0.075–0.100 mm/rev), and four cooling media (dry, MQL, flood, nanofluid) were used. Then, 5% Mo nanoparticles were added to the nanofluid cutting fluid. Machinability and power consumption analyses were carried out using the input parameters selected in light of the manufacturer’s recommendations and studies in the literature. The effects of sustainable cutting fluids and their parameters on machinability and power consumption were investigated through experiments. This study concluded that the use of nanofluid led to improvements in surface roughness, flank wear, and power consumption characteristics. It was determined that the flood environment is the most effective in reducing the cutting temperature. As a result, it is predicted that nanofluid cutting fluids can be used during machining.
Optimization of the Surface Roughness and Chip Compression Ratio of Duplex Stainless Steel in a Wet Turning Process Using the Taguchi Method
Authors: Gyliene Virginija , Brasas Algimantas , Ciuplys Antanas , Jablonskyte Janina
Published: June 2024

Duplex stainless steels (DSSs) are used in many applications due to their properties, such as high mechanical strength, good corrosion resistance, and relatively low cost. Nevertheless, DSS belongs to the materials group that is difficult to machine. The demand for a total increase in the production requires the optimization of cutting conditions. This paper examines the influence of cutting parameters, namely cutting velocity, feed, and the depth of cut on the surface roughness and chip compression ratio (CCR) after the DSS wet turning process. The study employed Taguchi optimization to determine the ideal cutting parameters for wet turning finishing operations on steel 1.4462. Using the Taguchi design, experiments focused on surface roughness (Ra) and CCR. Utilizing a TiAlN/TiN-PVD coating insert with a 0.4 mm nose radius, cutting velocity of 200 m/min, feed rates of 0.05 mm/rev, and cutting depths of 1 mm yielded the lowest Ra at 0.433 μm. Meanwhile, a cutting velocity of 200 m/min, feed rate of 0.15 mm/rev, and cutting depth of 0.5 mm resulted in the smallest CCR at 1.39, indicating minimal plastic deformation. The inclusion of additional cooling proved beneficial for surface roughness compared to dry and wet turning methods. The experimental data holds value for training and validating artificial intelligence models, preventing overfitting by ensuring sufficient data collection.
Prediction of Drilling Efficiency for Rotary Drilling Rig Based on an Improved Back Propagation Neural Network Algorithm
Authors: Jia Cunde , Zhang Junyong , Kong Xiangdong , Xu Hongyu , Jiang Wenguang , Li Shengbin , Jiang Yunhong , Ai Chao
Published: June 2024

Accurately predicting the drilling efficiency of rotary drilling is the key to achieving intelligent construction. The current types of principle analysis (based on traditional interactive experimental methods) and efficiency prediction (based on simulation models) cannot meet the requirements needed for the efficient, real-time, and accurate drilling efficiency predictions of rotary drilling rigs. Therefore, we adopted a method based on machine learning to predict drilling efficiency. The extremely complex rock fragmentation process in drilling conditions also brings challenges to predicting drilling efficiency. Therefore, this article went through a combination of mechanism and data analysis to conduct correlation analysis and to clarify the drilling characteristic parameters that are highly correlated with drilling efficiency, and it then used them as inputs for machine learning models. We propose a rotary drilling rig drilling efficiency prediction model based on the GA-BP neural network to construct an accurate and efficient drilling efficiency prediction model. Compared with traditional BP neural networks, it utilizes the global optimization ability of a genetic algorithm to obtain the initial weights and thresholds of a BP neural network in order to avoid the defect of ordinary BP neural networks, i.e., that they easily fall into local optimal solutions during the training process. The average prediction accuracy of the GA-BP neural network is 93.6%, which is 3.1% higher than the traditional BP neural network.
Existence Criteria and Related Relation of the gMP Inverse of Matrices
Authors: Xu Sanzhang , Zou Honglin , Zuo Kezheng
Published: June 2024

New characterizations of the gMP inverse are provided by the core part of the core-EP decomposition. We also answer the question as to whether X is the gMP inverse of A under the conditions of R(X)⊆R(A*Ak) or N((Ak)*)⊆N(X). We investigate the relationship between the core-EP inverse and the gMP inverse.Using the gMP inverse, the gMP relation is investigated in view of the core-EP decomposition.
Parameter Prediction with Novel Enhanced Wagner Hagras Interval Type-3 Takagi–Sugeno–Kang Fuzzy System with Type-1 Non-Singleton Inputs
Authors: Castorena Gerardo Armando Hernández , Méndez Gerardo Maximiliano , López-Juárez Ismael , García María Aracelia Alcorta , Martinez-Peon Dulce Citlalli , Montes-Dorantes Pascual Noradino
Published: June 2024

This paper presents the novel enhanced Wagner–Hagras interval type-3 Takagi–Sugeno–Kang fuzzy logic system with type-1 non-singleton inputs (EWH IT3 TSK NSFLS-1) that uses the backpropagation (BP) algorithm to train the antecedent and consequent parameters. The proposed methodology dynamically changes the parameters of only the alpha-0 level, minimizing some criterion functions as the current information becomes available for each alpha-k level. The novel fuzzy system was applied in two industrial processes and several fuzzy models were used to make comparisons. The experiments demonstrated that the proposed fuzzy system has a superior ability to predict the critical variables of the tested processes with lower prediction errors than those produced by the benchmark fuzzy systems.
Three-Step Iterative Algorithm for the Extended Cayley–Yosida Inclusion Problem in 2-Uniformly Smooth Banach Spaces: Convergence and Stability Analysis
Authors: Ali Imran , Wang Yuanheng , Ahmad Rais
Published: June 2024

In this article, we investigate and study an extended Cayley–Yosida inclusion problem. We show that our problem is equivalent to a fixed-point equation. Based on the fixed-point equation, we develop a three-step iterative algorithm to solve our problem. Finally, we illustrate the convergence of the proposed algorithm with an example, computational table, and convergence graph by using MATLAB 2018b.
A Mathematical Model for Integrated Disaster Relief Operations in Early-Stage Flood Scenarios
Authors: Insani Nur , Taheri Sona , Abdollahian Mali
Published: June 2024

When a flood strikes, the two most critical tasks are evacuation and relief distribution. It is essential to integrate these tasks, particularly before the floodwater reaches the vulnerable area, to minimize loss and damage. This paper presents a mathematical model of vehicle routing problems to optimize an integrated disaster relief operation. The model addresses routing for both the evacuation and relief distribution tasks in the early stages of a flood, aiming to identify a minimal number of vehicles required with their corresponding routes to transport vulnerable individuals and simultaneously distribute emergency relief. The new model incorporates several features, including vehicle reuse, multi-trip and split delivery scenarios for evacuees and emergency relief items, uncertainty in evacuation demands, and closing time windows at evacuation points. Due to the complexity of vehicle routing problems, particularly in large-scale scenarios, the exact approach for obtaining optimal solutions is time-consuming. Therefore, we propose the use of a metaheuristic algorithm, specifically a modified genetic algorithm, to find an approximate solution for the proposed model. We apply the developed model and modified algorithm to various simulated flood scenarios and a real-life case study from Indonesia. The experimental results demonstrate that our approach requires fewer vehicles compared to standard models for similar scenarios. Moreover, while the exact approach fails to find optimal solutions within a reasonable timeframe for large-scale scenarios, our new approach provides near-optimal solutions in a much shorter time. In smaller simulated scenarios, the modified genetic algorithm obtains optimal or near-optimal solutions approximately 92.5% faster than the exact approach.
Deceptive Path Planning via Count-Based Reinforcement Learning under Specific Time Constraint
Authors: Chen Dejun , Zeng Yunxiu , Zhang Yi , Li Shuilin , Xu Kai , Yin Quanjun
Published: June 2024

Deceptive path planning (DPP) aims to find a path that minimizes the probability of the observer identifying the real goal of the observed before it reaches. It is important for addressing issues such as public safety, strategic path planning, and logistics route privacy protection. Existing traditional methods often rely on “dissimulation”—hiding the truth—to obscure paths while ignoring the time constraints. Building upon the theory of probabilistic goal recognition based on cost difference, we proposed a DPP method, DPP_Q, based on count-based Q-learning for solving the DPP problems in discrete path-planning domains under specific time constraints. Furthermore, to extend this method to continuous domains, we proposed a new model of probabilistic goal recognition called the Approximate Goal Recognition Model (AGRM) and verified its feasibility in discrete path-planning domains. Finally, we also proposed a DPP method based on proximal policy optimization for continuous path-planning domains under specific time constraints called DPP_PPO. DPP methods like DPP_Q and DPP_PPO are types of research that have not yet been explored in the field of path planning. Experimental results show that, in discrete domains, compared to traditional methods, DPP_Q exhibits better effectiveness in enhancing the average deceptiveness of paths. (Improved on average by 12.53% compared to traditional methods). In continuous domains, DPP_PPO shows significant advantages over random walk methods. Both DPP_Q and DPP_PPO demonstrate good applicability in path-planning domains with uncomplicated obstacles.
Jacobi Stability Analysis of Liu System: Detecting Chaos
Authors: Liu Qinghui , Zhang Xin
Published: June 2024

By utilizing the Kosambi–Cartan–Chern (KCC) geometric theory, this paper is dedicated to providing novel insights into the Liu dynamical system, which stands out as one of the most distinctive and noteworthy nonlinear dynamical systems. Firstly, five important geometrical invariants of the system are obtained by associating the nonlinear connection with the Berwald connection. Secondly, in terms of the eigenvalues of the deviation curvature tensor, the Jacobi stability of the Liu dynamical system at fixed points is investigated, which indicates that three fixed points are Jacobi unstable. The Jacobi stability of the system is analyzed and compared with that of Lyapunov stability. Lastly, the dynamical behavior of components of the deviation vector is studied, which serves to geometrically delineate the chaotic behavior of the system near the origin. The onset of chaos for the Liu dynamical system is obtained. This work provides an analysis of the Jacobi stability of the Liu dynamical system, serving as a useful reference for future chaotic system research.
The Composition of Triterpene Glycosides in the Sea Cucumber Psolus peronii: Anticancer Activity of the Glycosides against Three Human Breast Cancer Cell Lines and Quantitative Structure–Activity Relationships (QSAR)
Authors: Silchenko Alexandra Sergeevna , Kalinovsky Anatoly Ivanovich , Avilov Sergey Anatolievich , Popov Roman Sergeevich , Chingizova Ekaterina Alexandrovna , Menchinskaya Ekaterina Sergeevna , Zelepuga Elena Alexandrovna , Tabakmakher Kseniya Mikhailovna , Stepanov Vadim Georgievich , Kalinin Vladimir Ivanovich
Published: June 2024

Eight sulfated triterpene glycosides, peronioside A (1) and psolusosides A (2), B (3), G (4), I (5), L (6), N (7) and P (8), were isolated from the sea cucumber Psolus peronii. Peronioside A (1) is a new glycoside, while compounds 2–8 were found previously in Psolus fabricii, indicating the phylogenetic and systematic closeness of these species of sea cucumbers. The activity of 1–8 against human erythrocytes and their cytotoxicity against the breast cancer cell lines MCF-7, T-47D and triple-negative MDA-MB-231 were tested. The most active against cancer cell compounds, psolusosides A (2) and L (6), which were not cytotoxic to the non-transformed cells of the mammary gland, were chosen to study the inhibition of the migration, formation and growth of colonies of the cancer cell lines. Glycoside 2 effectively inhibited the growth of colonies and the migration of the MDA-MB-231 cell line. Compound 6 blocked the growth of colonies of T-47D cells and showed a pronounced antimigration effect on MDA-MB-231 cells. The quantitative structure–activity relationships (QSAR) indicated the strong impact on the activity of the form and size of the molecules, which is connected to the length and architecture of the carbohydrate chain, the distribution of charge on the molecules’ surface and various aspects of hydrogen bond formation, depending on the quantity and positions of the sulfate groups. The QSAR calculations were in good accordance with the observed SAR tendencies.
Sulfated Polyhydroxysteroid Glycosides from the Sea of Okhotsk Starfish Henricia leviuscula spiculifera and Potential Mechanisms for Their Observed Anti-Cancer Activity against Several Types of Human Cancer Cells
Authors: Kicha Alla A. , Tolkanov Dmitriy K. , Malyarenko Timofey V. , Malyarenko Olesya S. , Kuzmich Alexandra S. , Kalinovsky Anatoly I. , Popov Roman S. , Stonik Valentin A. , Ivanchina Natalia V. , Dmitrenok Pavel S.
Published: June 2024

Three new monosulfated polyhydroxysteroid glycosides, spiculiferosides A (1), B (2), and C (3), along with new related unsulfated monoglycoside, spiculiferoside D (4), were isolated from an ethanolic extract of the starfish Henricia leviuscula spiculifera collected in the Sea of Okhotsk. Compounds 1–3 contain two carbohydrate moieties, one of which is attached to C-3 of the steroid tetracyclic core, whereas another is located at C-24 of the side chain of aglycon. Two glycosides (2, 3) are biosides, and one glycoside (1), unlike them, includes three monosaccharide residues. Such type triosides are a rare group of polar steroids of sea stars. In addition, the 5-substituted 3-OSO3-α-L-Araf unit was found in steroid glycosides from starfish for the first time. Cell viability analysis showed that 1–3 (at concentrations up to 100 μM) had negligible cytotoxicity against human embryonic kidney HEK293, melanoma SK-MEL-28, breast cancer MDA-MB-231, and colorectal carcinoma HCT 116 cells. These compounds significantly inhibited proliferation and colony formation in HCT 116 cells at non-toxic concentrations, with compound 3 having the greatest effect. Compound 3 exerted anti-proliferative effects on HCT 116 cells through the induction of dose-dependent cell cycle arrest at the G2/M phase, regulation of expression of cell cycle proteins CDK2, CDK4, cyclin D1, p21, and inhibition of phosphorylation of protein kinases c-Raf, MEK1/2, ERK1/2 of the MAPK/ERK1/2 pathway.
A Marine Collagen-Based 3D Scaffold for In Vitro Modeling of Human Prostate Cancer Niche and Anti-Cancer Therapeutic Discovery
Authors: Song Won Hoon , Lim Ye Seon , Kim Ji-Eun , Kang Hae Yeong , Lee Changyong , Rajbongshi Lata , Hwang Seon Yeong , Oh Sae-Ock , Kim Byoung Soo , Lee Dongjun , Song Yong Jung , Yoon Sik
Published: June 2024

Recently, the need to develop a robust three-dimensional (3D) cell culture system that serves as a valuable in vitro tumor model has been emphasized. This system should closely mimic the tumor growth behaviors observed in vivo and replicate the key elements and characteristics of human tumors for the effective discovery and development of anti-tumor therapeutics. Therefore, in this study, we developed an effective 3D in vitro model of human prostate cancer (PC) using a marine collagen-based biomimetic 3D scaffold. The model displayed distinctive molecular profiles and cellular properties compared with those of the 2D PC cell culture. This was evidenced by (1) increased cell proliferation, migration, invasion, colony formation, and chemoresistance; (2) upregulated expression of crucial multidrug-resistance- and cancer-stemness-related genes; (3) heightened expression of key molecules associated with malignant progressions, such as epithelial–mesenchymal transition transcription factors, Notch, matrix metalloproteinases, and pluripotency biomarkers; (4) robust enrichment of prostate cancer stem cells (CSCs); and (5) enhanced expression of integrins. These results suggest that our 3D in vitro PC model has the potential to serve as a research platform for studying PC and prostate CSC biology, as well as for screening novel therapies targeting PC and prostate CSCs.
Discovery of Prenyltransferase-Guided Hydroxyphenylacetic Acid Derivatives from Marine Fungus Penicillium sp. W21C371
Authors: Wang Cancan , Fan Ye , Wang Chenjie , Tang Jing , Qiu Yixian , Xu Keren , Ding Yingjia , Liu Ying , Ying Youmin , Wang Hong
Published: June 2024

Traditional isolation methods often lead to the rediscovery of known natural products. In contrast, genome mining strategies are considered effective for the continual discovery of new natural products. In this study, we discovered a unique prenyltransferase (PT) through genome mining, capable of catalyzing the transfer of a prenyl group to an aromatic nucleus to form C-C or C-O bonds. A pair of new hydroxyphenylacetic acid derivative enantiomers with prenyl units, (±)-peniprenydiol A (1), along with 16 known compounds (2–17), were isolated from a marine fungus, Penicillium sp. W21C371. The separation of 1 using chiral HPLC led to the isolation of the enantiomers 1a and 1b. Their structures were established on the basis of extensive spectroscopic analysis, including 1D, 2D NMR and HRESIMS. The absolute configurations of the new compounds were determined by a modified Mosher method. A plausible biosynthetic pathway for 1 was deduced, facilitated by PT catalysis. In the in vitro assay, 2 and 3 showed promising inhibitory activity against Escherichia coli β-glucuronidase (EcGUS), with IC50 values of 44.60 ± 0.84 μM and 21.60 ± 0.76 μM, respectively, compared to the positive control, D-saccharic acid 1,4-lactone hydrate (DSL). This study demonstrates the advantages of genome mining in the rational acquisition of new natural products.
An Update on Non-Invasive Skin Imaging Techniques in Actinic Keratosis—A Narrative Review
Authors: Korecka Katarzyna , Kwiatkowska Dominika , Mazur Ewelina , Dańczak-Pazdrowska Aleksandra , Reich Adam , Żaba Ryszard , Polańska Adriana
Published: June 2024

Nonmelanocytic skin cancers (NMSCs) are currently the most common group of human cancers and include all tumors that are not melanomas. Increased exposure to sunlight over the past few years, the lack of regular and proper use of sunscreen, the aging of the population, and better screening techniques are the reasons for the escalation in their diagnosis. Squamous cell carcinoma (SCC) comprises nearly 37% of the tumors in this group and can originate from actinic keratosis (AK), which usually presents as pink, often scaly plaques, usually located on the face or scalp. Advances in dermatoscopy, as well as the development of other non-invasive skin imaging modalities such as high-frequency ultrasound (HFUS), reflectance confocal microscopy (RCM), and optical coherence tomography (OCT), have allowed for greatly increased sensitivity in diagnosing these lesions and monitoring their treatment. Since AK therapy is usually local, and SCCs must be removed surgically, non-invasive imaging methods enable to correctly qualify difficult lesions. This is especially important given that they are very often located on the face, and achieving an appropriate cosmetic result after treatments in this area is very important for the patients. In this review, the authors describe the use of non-invasive skin imaging methods in the diagnosis of actinic keratosis.
Low Dietary Diversity and Low Haemoglobin Status in Ghanaian Female Boarding and Day Senior High School Students: A Cross-Sectional Study
Authors: Asare Joyce , Lim Jia Jiet , Amoah Isaac
Published: June 2024

Background and Objectives: Anaemia is one of the most common forms of malnutrition globally, with most anaemia cases related to micronutrient deficiency. Diets with higher dietary diversity scores (DDS) are usually nutritionally diverse and could positively impact micronutrient status, including haemoglobin (Hb) concentration improvement. The study aimed to determine DDS and its association with the Hb concentration of Boarding and Day adolescent Senior High School students in Ghana. Materials and Methods: A semi-structured and three 24 h dietary recalls were used to obtain the participants’ demographic and diet intake data, respectively. Hb concentration was assessed using a validated portable haemoglobinometer. DDS was evaluated using the Minimum Dietary Diversity for Women (MDD-W) approach. Results: A significant difference in the DDS between Boarding and Day students existed. Only 22% of the Boarding students had adequate dietary diversity, whereas 64% of the Day students had adequate dietary diversity. A significantly smaller proportion of the Boarding students consumed nuts and seeds, dairy, flesh foods, eggs, vitamin A-rich vegetables and fruits, other vegetables, and other fruits compared to Day students (p < 0.05, all). No significant difference (p = 0.925) in mean (±SD) Hb concentrations between Boarding (11.9 ± 1.1 g/dL) and Day (11.9 ± 1.1 g/dL) students was found. Additionally, no significant correlation between mean DDS and Hb concentration (p = 0.997) was recorded. Using Hb < 12 g/dL as the determination of anaemia, 55.1% Boarding and 57.8% Day students had anaemia. Conclusions: Low dietary diversity in Boarding students highlighted inadequate nutrition provided by school meals. Strategies to increase meal diversity should be prioritised by stakeholders in Ghana’s educational sector.
The Modified Harrington Procedure for Metastatic Peri-Acetabular Bone Lesion Using a Novel Highly Porous Titanium Revision Shell with Long Lever Arm Screw
Authors: Frieler Sven , Gebert Carsten , Hanusrichter Yannik , Godolias Periklis , Wessling Martin
Published: June 2024

Background and Objectives: Peri-acetabular metastases often lead to significant pain and functional impairment. Surgical interventions, including the Harrington procedure, aim to address these challenges. This study evaluates a modified Harrington procedure using the MUTARS® PRS® (Pelvic Revision Shell) with an 8 mm fixation screw for severe acetabular defects resulting from metastatic lesions. Materials and Methods: Retrospective analysis of 12 patients treated between January 2020 and December 2023 was conducted. The procedure involved using the novel MUTARS® PRS® with an 8 mm in diameter dome screw (length 70–100 mm). Outcome measures included implant positioning changes, complication rates, functional outcomes, implant longevity, and patient survival. Radiological assessments were performed postoperatively, with follow-ups at 3, 6, 12 months, and annually thereafter. Results: Average follow-up was 15 ± 11 months, with 67% patient survival at 1 year and 44% at 2 years. Implant survivorship remained 100%. Harris Hip Score improved significantly from 37 ± 22 preoperatively to 75 ± 15 at the last follow-up. No revisions involving implant components were reported. Complications occurred in 5 of 12 patients. Overall, PRS® demonstrates effective osseous ingrowth, high primary stability, immediate full weight-bearing, and low complication rates. Conclusions: PRS® integrates facilitating osseous ingrowth for preferable long-term outcomes, while efficiently transmitting the weight-bearing load to the intact aspect of the pelvis using a long 8 mm lever screw, enhancing the primary stability of the construct. It proves to be an effective and reproducible technique for managing destructive metastatic lesions of the acetabulum and peri-acetabular region, even in irradiated bone.
The Relationship between Job Strain and Ischemic Heart Disease Mediated by Endothelial Dysfunction Markers and Imaging
Authors: Moisii Paloma , Jari Irina , Ursu Andra Mara , Naum Alexandru Gratian
Published: June 2024

Background and Objectives: Job strain is a psychological, physical, and behavioral stress that occurs at the workplace. Job strain is associated with more than double the normal risk of coronary artery disease (CAD). The main aim of this study was to determine the association between job strain and the following parameters: high-sensitivity C-reactive protein (hs-CRP), the albumin urine excretion rate (AUER), and secondary-level testing. Materials and Methods: This study was a descriptive cross-sectional study conducted on patients who underwent cardiological assessment between October 2023 and February 2024 at the Promedicanon Cardiology Center. This study comprised 210 participants, with two groups: 105 chronic coronary syndromes (CCS) patients and 105 no-CCS patients. The baseline characteristics collected were age, gender, education, rural/urban environment, traditional CAD risk factors, hs-CRP, and AUER. The secondary-level testing included an electrocardiogram (ECG), echocardiography, and enhanced contrast computed tomography (ECCT). Psychological questionnaires comprised the tertiary-level testing, including the PHQ-9 depression questionnaire, and the satisfaction with work scale (SWWS) for job strain (Likert score). Results: The baseline characteristics were all significantly different between the groups (p < 0.05) except for total cholesterol. The hs-CRP level had a mean value of 0.4837 ± 0.19082 in the CCS group; for the no-CCS group, the hs-CRP mean value was 0.2289 ± 0.11009; p-value < 0.001. The AUER had a mean value of 42.770 ± 12.8658 for the CCS group and 26.432 ± 9.7338 for the no-CCS group; p-value < 0.001. For the associations between secondary-level testing and job strain: p < 0.001 for ST depression, negative T-waves, and q-waves; p = 0.415 for atrial fibrillation (AF); p = 0.018 for wall motion studies; p = 0.005 for ECCT. The association between job strain and AF had no statistical significance. The contractility of left ventricle walls and coronary calcification score were associated with job strain, with statistical significance. The p-value was 0.013 for the relationship between depression and the ECCT; for the association between depression and CCS status, the p-value was 0.021. Depression is usually diagnosed in job strain. The association between depression, and coronary calcification, as well as depression and CCS status had statistical significance. Conclusions: Job strain increased the hs-CRP level and AUER in both the CCS and no-CCS patients. The primary and secondary prevention of CHD could also include interventions to reduce job strain.
The Role of Glial Fibrillary Acidic Protein as a Biomarker in Multiple Sclerosis and Neuromyelitis Optica Spectrum Disorder: A Systematic Review and Meta-Analysis
Authors: Shaygannejad Aysa , Rafiei Nazanin , Vaheb Saeed , Yazdan Panah Mohammad , Shaygannejad Vahid , Mirmosayyeb Omid
Published: June 2024

There is debate on the role of glial fibrillary acidic protein (GFAP) as a reliable biomarker in multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD), and its potential to reflect disease progression. This review aimed to investigate the role of GFAP in MS and NMOSD. A systematic search of electronic databases, including PubMed, Embase, Scopus, and Web of Sciences, was conducted up to 20 December 2023 to identify studies that measured GFAP levels in people with MS (PwMS) and people with NMOSD (PwNMOSD). R software version 4.3.3. with the random-effect model was used to pool the effect size with its 95% confidence interval (CI). Of 4109 studies, 49 studies met our inclusion criteria encompassing 3491 PwMS, 849 PwNMOSD, and 1046 healthy controls (HCs). The analyses indicated that the cerebrospinal fluid level of GFAP (cGFAP) and serum level of GFAP (sGFAP) were significantly higher in PwMS than HCs (SMD = 0.7, 95% CI: 0.54 to 0.86, p < 0.001, I2 = 29%, and SMD = 0.54, 95% CI: 0.1 to 0.99, p = 0.02, I2 = 90%, respectively). The sGFAP was significantly higher in PwNMOSD than in HCs (SMD = 0.9, 95% CI: 0.73 to 1.07, p < 0.001, I2 = 10%). Among PwMS, the Expanded Disability Status Scale (EDSS) exhibited significant correlations with cGFAP (r = 0.43, 95% CI: 0.26 to 0.59, p < 0.001, I2 = 91%) and sGFAP (r = 0.36, 95% CI: 0.23 to 0.49, p < 0.001, I2 = 78%). Regarding that GFAP is increased in MS and NMOSD and has correlations with disease features, it can be a potential biomarker in MS and NMOSD and indicate the disease progression and disability in these disorders.
Antagonistic Effects of Corynebacterium pseudodiphtheriticum 090104 on Respiratory Pathogens
Authors: Ortiz Moyano Ramiro , Dentice Maidana Stefania , Imamura Yoshiya , Elean Mariano , Namai Fu , Suda Yoshihito , Nishiyama Keita , Melnikov Vyacheslav , Kitazawa Haruki , Villena Julio
Published: June 2024

In previous studies, it was demonstrated that Corynebacterium pseudodiphtheriticum 090104, isolated from the human nasopharynx, modulates respiratory immunity, improving protection against infections. Here, the antagonistic effect of the 090104 strain on respiratory pathogens, including Streptococcus pneumoniae, Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii, was explored. In a series of in vitro studies, the capacity of C. pseudodiphtheriticum 090104, its bacterium-like particles, and its culture supernatants to coaggregate, inhibit the growth, and change the virulent phenotype of pathogenic bacteria was evaluated. The results showed that the 090104 strain was able to exert a bacteriostatic effect on K. pneumoniae and S. pneumoniae growth. In addition, C. pseudodiphtheriticum 090104 coaggregated, inhibited biofilm formation, and induced phenotypic changes in all the respiratory pathogens evaluated. In conclusion, this work demonstrated that, in addition to its beneficial effects exerted by host–microbe interactions, C. pseudodiphtheriticum 090104 can enhance protection against respiratory pathogens through its microbe–microbe interactions. The mechanisms involved in such interactions should be evaluated in future research.
The Relationship between Biofilm Phenotypes and Biofilm-Associated Genes in Food-Related Listeria monocytogenes Strains
Authors: Burdová Alexandra , Véghová Adriana , Minarovičová Jana , Drahovská Hana , Kaclíková Eva
Published: June 2024

Listeria monocytogenes is an important pathogen responsible for listeriosis, a serious foodborne illness associated with high mortality rates. Therefore, L. monocytogenes is considered a challenge for the food industry due to the ability of some strains to persist in food-associated environments. Biofilm production is presumed to contribute to increased L. monocytogenes resistance and persistence. The aims of this study were to (1) assess the biofilm formation of L. monocytogenes isolates from a meat processing facility and sheep farm previously characterized and subjected to whole-genome sequencing and (2) perform a comparative genomic analysis to compare the biofilm formation and the presence of a known set of biofilm-associated genes and related resistance or persistence markers. Among the 37 L. monocytogenes isolates of 15 sequence types and four serogroups involved in this study, 14%, 62%, and 24% resulted in the formation of weak, moderate, and strong biofilm, respectively. Increased biofilm-forming ability was associated with the presence of the stress survival islet 1 (SSI-1), inlL, and the truncated inlA genes. Combining the phenotypic and genotypic data may contribute to understanding the relationships between biofilm-associated genes and L. monocytogenes biofilm-forming ability, enabling improvement in the control of this foodborne pathogen.
Phaseolotoxin: Environmental Conditions and Regulatory Mechanisms Involved in Its Synthesis
Authors: Arvizu-Gómez Jackeline Lizzeta , Hernández-Morales Alejandro , Campos-Guillén Juan , González-Reyes Christian , Pacheco-Aguilar Juan Ramiro
Published: June 2024

Phaseolotoxin is an antimetabolite toxin produced by diverse pathovars of Pseudomonas syringae which affects various plants, causing diseases of economic importance. Phaseolotoxin contributes to the systemic dissemination of the pathogen in the plant, therefore it is recognized as a major virulence factor. Genetic traits such as the Pht cluster, appear defining to the toxigenic strains phaseolotoxin producers. Extensive research has contributed to our knowledge concerning the regulation of phaseolotoxin revealing a complex regulatory network that involves processes at the transcriptional and posttranscriptional levels, in which specific and global regulators participate. Even more, significant advances in understanding how specific signals, including host metabolites, nutrient sources, and physical parameters such as the temperature, can affect phaseolotoxin production have been made. A general overview of the phaseolotoxin regulation, focusing on the chemical and physical cues, and regulatory pathways involved in the expression of this major virulence factor will be given in the present work.
Insights into Chlamydia Development and Host Cells Response
Authors: Yang Shuaini , Zeng Jiajia , Yu Jinxi , Sun Ruoyuan , Tuo Yuqing , Bai Hong
Published: June 2024

Chlamydia infections commonly afflict both humans and animals, resulting in significant morbidity and imposing a substantial socioeconomic burden worldwide. As an obligate intracellular pathogen, Chlamydia interacts with other cell organelles to obtain necessary nutrients and establishes an intracellular niche for the development of a biphasic intracellular cycle. Eventually, the host cells undergo lysis or extrusion, releasing infectious elementary bodies and facilitating the spread of infection. This review provides insights into Chlamydia development and host cell responses, summarizing the latest research on the biphasic developmental cycle, nutrient acquisition, intracellular metabolism, host cell fates following Chlamydia invasion, prevalent diseases associated with Chlamydia infection, treatment options, and vaccine prevention strategies. A comprehensive understanding of these mechanisms will contribute to a deeper comprehension of the intricate equilibrium between Chlamydia within host cells and the progression of human disease.
Editorial for the Special Issue: “Valuable Metals Recovery by Mineral Processing and Hydrometallurgy”
Authors: Panayotova Marinela , Panayotov Vladko
Published: June 2024

Achieving the sustainable development of our society and facilitating breakthrough innovations necessitates metals [...]
A Novel Method of Magnetic Sources Edge Detection Based on Gradient Tensor
Authors: Lv Wenjie , Huang Pei , Yang Yaxin , Luo Qibin , Xie Shangping , Fu Chen
Published: June 2024

The edge detection method based on the magnetic gradient tensor data plays an important role in magnetic exploration because it is free from geomagnetic interference and contains more abundant information. This paper proposes a new anomaly edge detection method using the magnetic gradient tensor components. The model is established to compare with other methods, such as directional total horizontal derivative (THDz), analytical signal (AS), tilt angle, theta map, and so on, under conditions of vertical magnetization, oblique magnetization, and noise interference. Through the study of the anomaly distribution of the rectangular model, it is observed that the edge detection method proposed in this paper is nearly impervious to noise interference, exhibits strong anti-interference capabilities, delivers a high-quality boundary identification effect, and provides greater accuracy in anomaly edges with minimal error. When multiple anomalous bodies are present, the edge detection results are less susceptible to interference from each other, resulting in higher resolution. The efficiency of the algorithm is demonstrated by real magnetic data from some study areas in Jiangxi Province, China. The experimental results show that the proposed method is more precise and accurate than the total horizontal derivative, analytical signal, tilt angle, and theta map methods.