bluuebunny/crossref_metadata_2025 huggingface dataset:
Adaptive Machining Method for Helical Milling of Carbon Fiber-Reinforced Plastic/Titanium Alloy Stacks Based on Interface Identification
Authors: Yan Chao , Kang Renke , Meng Fantong , Dong Zhigang , Bao Yan , Yang Guolin
Published: January 2024

CFRP/Ti stacks composed of carbon fiber-reinforced plastic composites (CFRP) and titanium alloys (Ti) are widely used in aerospace fields. However, in the integrated hole-making process of CFRP/Ti stacks, the machining characteristics of various materials are significantly different, and constant machining parameters cannot simultaneously meet the high-quality machining requirements of two materials. In addition, errors exist between the actual thickness of each material layer and the theoretical value, which causes an impediment to the monitoring of the machining interface and the corresponding adjustment of parameters. An adaptive machining method for the helical milling of CFRP/Ti stacks based on interface identification is proposed in this paper. The machining characteristics of the pneumatic spindle and the interface state in the helical milling of CFRP/Ti stacks are analyzed using self-developed portable helical milling equipment, and a new algorithm for the real-time monitoring of the machining interface position and adaptive adjustment of the machining parameters according to the interface identification result is proposed. Helical milling experiments were carried out, the results show that the proposed method can effectively identify the position of the machining interface with good identification accuracy. Moreover, the proposed parameter-adaptive optimized machining method for CFRP/Ti stacks can significantly improve hole diameter accuracy and machining quality.
Materials Enabling Methane and Toluene Gas Treatment
Authors: Lv Tong , Wang Rui
Published: January 2024

This paper summarizes the latest research results on materials for the treatment of methane, an important greenhouse gas, and toluene, a volatile organic compound gas, as well as the utilization of these resources over the past two years. These materials include adsorption materials, catalytic oxidation materials, hydrogen-reforming catalytic materials and non-oxidative coupling catalytic materials for methane, and adsorption materials, catalytic oxidation materials, chemical cycle reforming catalytic materials, and degradation catalytic materials for toluene. This paper provides a comprehensive review of these research results from a general point of view and provides an outlook on the treatment of these two gases and materials for resource utilization.
Effects of Different Heating and Cooling Rates during Solution Treatment on Microstructure and Properties of AA7050 Alloy Wires
Authors: Gao Xinyu , Gao Guanjun , Li Zhihui , Li Xiwu , Yan Lizhen , Zhang Yongan , Xiong Baiqing
Published: January 2024

In the present study, the effects of varying heating and cooling rates during the solution treatment process on the microstructure and properties of AA7050 alloy wires were investigated using tensile tests, metallographic microscopy, electron backscattered diffraction, and transmission electron microscopy. It was found that the recrystallized grain size of the alloy, subjected to method of rapid heating, exhibited a smaller and more uniform distribution in comparison to method of slow heating. The low density of η′ strengthening phases after the artificial aging treatment was formed using air cooling method. Meanwhile, by using the water quenching method sufficient solute atoms and more nucleation sites were provided resulting in a large number of η′ strengthening phases being formed. In addition, the alloy processed using the water quenching method displayed higher strength than that treated using the air cooling method for the T6 and T73 states. Furthermore, coarse precipitates formed and less clusters were observed in the matrix, while high density nanoscale clusters and no continuous precipitation are formed when using the water quenching method.
Optoelectronic Properties of Cold Plasma-Deposited, Oxidized Sn–C Thin Films
Authors: Frątczak Ewelina , Balcerzak Jacek , Rogala Maciej
Published: January 2024

We report on investigating the structural and electronic properties of semiconducting and insulating layers produced in a process resembling percolation in a unique cold plasma fabrication method (plasma-enhanced chemical vapor deposition—PECVD). Amorphous carbon–tin films (Sn–C) produced from tetramethyl tin (TMT) with an acoustic-frequency glow discharge in a three-electrode reactor were investigated. The layers, after air exposure, oxidized to SnO2/Sn–C. Depending on the coupling capacitance applied to the plasma reactor, the films could be obtained in the form of an amorphous semiconductor or an amorphous insulator. We assume that the semiconductor consists of an internal network of channels auto-organized during deposition. The insulator does not demonstrate any internal structure features. An investigation on conductive filaments creating low-dimensional (LD) nanojunctions in the semiconductor and the location of energetic levels in the insulator was performed. The main parameters of the electronic band structure of the insulating film, such as the transport gap EG (5.2 eV), optical gap Eopt (3.1 eV), electron affinity Χ (2.1 eV), and ionization potential J (7.3 eV), were determined. We have demonstrated a simple approach for developing a catalyst candidate consisting of amorphous semiconductor–insulator nanojunctions for (photo)catalytic hydrogen evolution or CO2 reduction.
Design of Special Equipment for the Mechanical Testing of Runway Light Fixtures
Authors: Croccolo Dario , De Agostinis Massimiliano , Fini Stefano , Mele Mattia , Olmi Giorgio , Scapecchi Chiara
Published: January 2024

Runway lights are essential components of the airstrip. However, there is currently no international standard that outlines methods for the testing of runway light fixtures. In this study, a novel testing method is developed to simulate the forces exerted on the lights during landing. The testing equipment is specifically designed to be easily mounted on a standard hydraulic press commonly used for tensile tests. This system allows for the regulation of the normal force between the aircraft tire and the fixture of the runway lighting system. To minimize load fluctuations during part sliding, Belleville washers are employed. The overall compliance of the system is validated through finite element analysis. Tests carried out by means of the proposed testing equipment allow the effective description of the variations in load at different positions during sliding. The system presented in this paper can be used to investigate the effects of landing on various combinations of cap design and tire material.
Hypothesis Test to Compare Two Paired Binomial Proportions: Assessment of 24 Methods
Authors: Roldán-Nofuentes José Antonio , Sheth Tulsi Sagar , Vera-Vera José Fernando
Published: January 2024

The comparison of two paired binomial proportions is a topic of interest in statistics, with important applications in medicine. There are different methods in the statistical literature to solve this problem, and the McNemar test is the best known of all of them. The problem has been solved from a conditioned perspective, only considering the discordant pairs, and from an unconditioned perspective, considering all of the observed values. This manuscript reviews the existing methods to solve the hypothesis test of equality for the two paired proportions and proposes new methods. Monte Carlo simulation methods were carried out to study the asymptotic behaviour of the methods studied, giving some general rules of application depending on the sample size. In general terms, the Wald test, the likelihood-ratio test, and two tests based on association measures in 2 × 2 tables can always be applied, whatever the sample size is, and if the sample size is large, then the McNemar test without a continuity correction and the modified Wald test can also be applied. The results have been applied to a real example on the diagnosis of coronary heart disease.
Lp Bounds for Rough Maximal Operators along Surfaces of Revolution on Product Domains
Authors: Ali Mohammed , Al-Qassem Hussain
Published: January 2024

In this paper, we study the boundedness of rough Maximal integral operators along surfaces of revolution on product domains. For several classes of surfaces, we establish appropriate Lp bounds of these Maximal operators under the assumption Ω∈Lq(Sm−1×Sn−1) for some q>1, and then we employ these bounds along with Yano’s extrapolation argument to obtain the Lp boundedness of the aforementioned integral operators under a weaker condition in which Ω belongs to either the space Bq(0,2τ′−1)(Sm−1×Sn−1) or to the space L(logL)2/τ′(Sm−×Sn−1). Our results extend and improve many previously known results.
On the Control Policy of a Queuing–Inventory System with Variable Inventory Replenishment Speed
Authors: Baek Jung Woo
Published: January 2024

This paper considers a make-to-order production–inventory system that comprises a production facility and an inventory warehouse. Customers arrive at the facility to place an order, and the orders are processed using the first-come-first-served (FCFS) discipline. The warehouse supplies inventory items (raw materials) for the production process, and the warehouse inventory is replenished by internal production. The speed of internal production can be controlled through additional costs. If the inventory level drops to zero, the unmet demand waits in the facility until the inventory is replenished. During the stockout period, newly arriving demand is lost. The stationary joint probability of unmet demands and inventory items is derived, and a cost model is constructed. The optimal control policy for internal production is investigated to minimize the cost per unit time of the system. The experimental results show that such a production speed adjustment could reduce costs by up to 42% compared to the cases without the adjustment.
On a Linear Differential Game of Pursuit with Integral Constraints in ℓ2
Authors: Zaynabiddinov Ibroximjon , Ruziboev Marks , Ibragimov Gafurjan , Ciano Tiziana
Published: January 2024

In this paper, we study the stability, controllability, and differential game of pursuit for an infinite system of linear ODEs in ℓ2. The system we consider has a special right-hand side, which is not diagonal and serves as a toy model for controllable system of infinitely many interacting points. We impose integral constraints on the control parameters. We obtain criteria for stability and null controllability of the system. Further, we construct a strategy for the pursuer that guarantees completion of the pursuit problem for the differential game. To prove controllability we use the so called Gramian operators.
Stability Margin of Data-Driven LQR and Its Application to Consensus Problem
Authors: Umar Abdul Aris , Ryu Kunhee , Back Juhoon , Kim Jung-Su
Published: January 2024

In contrast with traditional control input design techniques based on mathematical models of the system, in data-driven control approaches, which have recently gained substantial attention, the controller is derived directly from the data that are collected from experiments or observations of the target system. In particular, several data-driven optimal control and model predictive control (MPC) techniques have been proposed. In this paper, it is shown that the recently proposed data-driven LQR (Linear Quadratic Regulator) has a stability margin that is the set of the uncertainties in the control input channels maintaining the closed-loop stability. As an application of the proposed stability margin of the data-driven LQR, the consensus problem is considered. Since the control design for the consensus of multi-agent systems can be reformulated into the robust stabilization of a linear system with uncertainty in the input channel, it is demonstrated that the derived stability margin can be used to design a controller for the consensus of multi-agent systems.
Entropy Cost of ‘Erasure’ in Physically Irreversible Processes
Authors: Kastner Ruth E. , Schlatter Andreas
Published: January 2024

A restricted form of Landauer’s principle, independent of computational considerations, is shown to hold for thermal systems by reference to the joint entropy associated with conjugate observables. It is shown that the source of the compensating entropy for irreversible physical processes is due to the ontological uncertainty attending values of such mutually incompatible observables, rather than due to epistemic uncertainty, as traditionally assumed in the information-theoretic approach. In particular, it is explicitly shown that erasure of logical (epistemic) information via reset operations is not equivalent to erasure of thermodynamic entropy, so that the traditional, information-theoretic form of Landauer’s principle is not supported by the physics. A further implication of the analysis is that, in principle, there can be no Maxwell’s Demon in the real world.
Mathematical Formulation and Numerical Simulation of the Mechanical Behavior of Ceramic/Metal (TiB/Ti) FG Sheets Subjected to Spherical Indenter
Authors: Kessentini Amir , Allouch Marwa , Jrad Hanen , Mars Jamel , Ben Said Lotfi , Alhadri Muapper , Wali Mondher , Dammak Fakhreddine
Published: January 2024

The main motivation for the present work is to provide an improved description of the response of Functionally Graded (FG) structures under a spherical indenter, considering material nonlinearities. This is achieved through the implementation of elastoplastic material behavior using integration points to avoid the division of the structure into multiple layers. The current paper proposes a numerical investigation into the mechanical response of functionally graded materials (FGMs) in contact with a rigid hemispherical head indenter. The numerical model considers both the Mori–Tanaka model and self-consistent formulas of Suquet to accurately model the smooth variation of material properties through the thickness of the elastoplastic FG material. The model execution involves a UMAT user material subroutine to implement the material behavior into ABAQUS/Standard. The user material UMAT subroutine is employed to introduce material properties based on the integration points, allowing for an accurate representation and analysis of the material’s behavior within the simulation. The developed numerical model is validated through a comparison with experimental results from the literature, showing a good correlation that proves the efficiency of the proposed model. Then, a parametric study is conducted to analyze the effect of the indenter dimension, the indentation depth and the gradient index on the indentation force, the contact pressure evolution, von Mises equivalent stress and equivalent plastic strain distributions located on the vicinity of the contact zone. The results showed that the elastoplastic response of TiB/Ti FG plates is significantly influenced by the gradient index, which determines the properties of the FG composite through the thickness. These results may help development engineers choose the optimal gradation for each industrial application in order to avoid contact damage.
New Polyene Macrolide Compounds from Mangrove-Derived Strain Streptomyces hiroshimensis GXIMD 06359: Isolation, Antifungal Activity, and Mechanism against Talaromyces marneffei
Authors: Wang Zhou , Yin Jianglin , Bai Meng , Yang Jie , Jiang Cuiping , Yi Xiangxi , Liu Yonghong , Gao Chenghai
Published: January 2024

Mangrove-derived actinomycetes represent a rich source of novel bioactive natural products in drug discovery. In this study, four new polyene macrolide antibiotics antifungalmycin B-E (1–4), along with seven known analogs (5–11), were isolated from the fermentation broth of the mangrove strain Streptomyces hiroshimensis GXIMD 06359. All compounds from this strain were purified using semi-preparative HPLC and Sephadex LH-20 gel filtration while following an antifungal activity-guided fractionation. Their structures were elucidated through spectroscopic techniques including UV, HR-ESI-MS, and NMR. These compounds exhibited broad-spectrum antifungal activity against Talaromyces marneffei with minimum inhibitory concentration (MIC) values being in the range of 2–128 μg/mL except compound 2. This is the first report of polyene derivatives produced by S. hiroshimensis as bioactive compounds against T. marneffei. In vitro studies showed that compound 1 exerted a significantly stronger antifungal activity against T. marneffei than other new compounds, and the antifungal mechanism of compound 1 may be related to the disrupted cell membrane, which causes mitochondrial dysfunction, resulting in leakage of intracellular biological components, and subsequently, cell death. Taken together, this study provides a basis for compound 1 preventing and controlling talaromycosis.
Direct Anterior Approach in Total Hip Arthroplasty for Severe Crowe IV Dysplasia: Retrospective Clinical and Radiological Study
Authors: Faldini Cesare , Tassinari Leonardo , Pederiva Davide , Rossomando Valentino , Brunello Matteo , Pilla Federico , Geraci Giuseppe , Traina Francesco , Di Martino Alberto
Published: January 2024

Background and Objectives: total hip arthroplasty (THA) for Crowe IV hip dysplasia poses challenges due to severe leg shortening, muscle retraction and bone stock issues, leading to an increased neurological complication, and revision rate. The direct anterior approach (DAA) is used for minimally invasive THA but its role in Crowe IV dysplasia is unclear. This retrospective study examines if DAA effectively restores hip biomechanics in Crowe IV dysplasia patients with <4 cm leg length discrepancy, managing soft tissue and yielding functional improvement, limb length correction, and limited complications. Materials and Methods: 19 patients with unilateral Crowe IV hip osteoarthritis and <4 cm leg length discrepancy undergoing DAA THA were reviewed. Surgery involved gradual soft tissue release, precise acetabular cup positioning, and stem placement without femoral osteotomy. Results: results were evaluated clinically and radiographically, with complications recorded. Follow-up revealed significant Harris Hip Score and limb length discrepancy improvements. Abductor muscle insufficiency was present in 21%. The acetabular component was accurately placed, centralizing the prosthetic joint’s rotation. Complications occurred in 16% of cases, including fractures, nerve issues, and infection. DAA in THA showcased positive outcomes for hip function, limb length, and biomechanics in Crowe IV dysplasia. Conclusions: the technique enabled accurate cup positioning and rotation center adjustment. Complications were managed well without implant revisions. DAA is a viable option for Crowe IV dysplasia, restoring hip function, biomechanics, and reducing limb length discrepancy. Larger, longer studies are needed for validation.
Mild Behavioral Impairment in Parkinson’s Disease: An Updated Review on the Clinical, Genetic, Neuroanatomical, and Pathophysiological Aspects
Authors: Angelopoulou Efthalia , Bougea Anastasia , Hatzimanolis Alexandros , Stefanis Leonidas , Scarmeas Nikolaos , Papageorgiou Sokratis
Published: January 2024

Neuropsychiatric symptoms (NPS), including depression, anxiety, apathy, visual hallucinations, and impulse control disorders, are very common during the course of Parkinson’s disease (PD), occurring even at the prodromal and premotor stages. Mild behavioral impairment (MBI) represents a recently described neurobehavioral syndrome, characterized by the emergence of persistent and impactful NPS in later life, reflecting arisk of dementia. Accumulating evidence suggests that MBI is highly prevalent in non-demented patients with PD, also being associated with an advanced disease stage, more severe motor deficits, as well as global and multiple-domain cognitive impairment. Neuroimaging studies have revealed that MBI in patients with PD may be related todistinct patterns of brain atrophy, altered neuronal connectivity, and distribution of dopamine transporter (DAT) depletion, shedding more light on its pathophysiological background. Genetic studies in PD patients have also shown that specific single-nucleotide polymorphisms (SNPs) may be associated with MBI, paving the way for future research in this field. In this review, we summarize and critically discuss the emerging evidence on the frequency, associated clinical and genetic factors, as well as neuroanatomical and neurophysiological correlates of MBI in PD, aiming to elucidate the underlying pathophysiology and its potential role as an early “marker” of cognitive decline, particularly in this population. In addition, we aim to identify research gaps, and propose novel relative areas of interest that could aid in our better understanding of the relationship of this newly defined diagnostic entity with PD.
An Online Monitoring Approach of Carbon Steel Corrosion via the Use of Electrochemical Noise and Wavelet Analysis
Authors: Abdulmutaali Ahmed , Hou Yang , Aldrich Chris , Lepkova Katerina
Published: January 2024

In this study, carbon steel was examined under different corrosive conditions using electrochemical noise (EN) as the primary method of investigation. The corroded carbon steel surfaces were examined using 3D profilometry to gather information about localized defects (pits). A post-EN analysis approach was used using the discrete wavelet transform (DWT) method, which emphasizes the necessity of employing wavelet analysis as a quantitative analysis approach for electrochemical noise. A well-established approach to extract features from wavelet scalogram images, based on the concept of local binary patterns (LBPs), was used to extract features from these wavelet images. The results demonstrated that electrochemical noise associated with wavelet transform analysis, particularly wavelet scalograms, is an effective tool for monitoring the localized corrosion of carbon steel.
Structure, Phase Composition, and Mechanical Properties of ZK51A Alloy with AlN Nanoparticles after Heat Treatment
Authors: Akhmadieva Anastasia A. , Khrustalev Anton P. , Grigoriev Mikhail V. , Zhukov Ilya A. , Vorozhtsov Alexander B.
Published: January 2024

The paper studies the influence of the content of aluminum nitride nanoparticles on the structure and mechanical properties of the ZK51A magnesium alloy. The microstructure investigations with optical and electron microscopy show that 1 wt.% AlN promotes the best grain refinement and size distribution. According to tensile strength testing of the ZK51A alloy, grain refinement is not a dominating mechanism in the property improvement of the alloy after heat treatment. The maximum values of mechanical parameters are achieved at the lowest (0.1 wt.%) content of aluminum nitride. The main mechanism of mechanical characteristics increase with the addition of AlN nanoparticles is dispersion hardening.
On the Role of ZrN Particles in the Microstructural Development in a Beta Titanium Alloy Processed by Laser Powder Bed Fusion
Authors: Chen Xu , Qiu Chunlei
Published: January 2024

Additive manufacturing of titanium alloys usually ends up with large columnar grains due to the steep thermal gradients within melt pools during solidification. In this study, ZrN particles were added into a beta titanium alloy, Ti-10V-2Fe-3Al, with the aim of promoting columnar-to-equiaxed grain transition during laser bed powder fusion (L-PBF). It was found that the addition of ZrN leads to the development of alternate layers of equiaxed grains and refined columnar grains, which is in sharp contrast to the dominant large columnar grains formed in the pure L-PBF-processed titanium alloy. An investigation on single laser melted tracks revealed that the sample with added ZrN showed fine equiaxed grains in the upper regions of solidified melt pools and columnar grains in the lower regions, whereas the solidified melt pools of the pure titanium alloy were dominated by large columnar grains due to epitaxial growth from the previous layer. The formation of equiaxed grains in the former sample is attributed to multiple factors including an increased gradient of liquidus temperature due to the solution of N and a reduced actual melt temperature gradient due to the melting of high-melting-point ZrN particles, which would have expanded constitutional undercooling, a grain growth restriction effect induced by the segregation of N along grain boundaries and the accumulation of unmelted ZrN particles in the upper regions of melt pools. The addition of ZrN also resulted in significant α precipitation, which showed strong variant selection and was found to be driven by laser reheating and the N solution in the matrix.
Enhancing Electrochemical Non-Enzymatic Dopamine Sensing Based on Bimetallic Nickel/Cobalt Phosphide Nanosheets
Authors: Wang Zhi-Yuan , Tsai Zong-Ying , Chang Han-Wei , Tsai Yu-Chen
Published: January 2024

In this study, the successful synthesis of bimetallic nickel/cobalt phosphide nanosheets (Ni-Co-P NSs) via the hydrothermal method and the subsequent high-temperature phosphorization process were both confirmed. Ni-Co-P NSs exhibited excellent electrocatalytic activity for the electrochemical non-enzymatic DA sensing. The surface morphologies and physicochemical properties of Ni-Co-P NSs were characterized by atomic force microscopy (AFM), field-emission scanning (FESEM), field-emission transmission electron microscopy (FETEM), and X-ray diffraction (XRD). Further, the electrochemical performance was evaluated by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The metallic nature of phosphide and the synergistic effect of Ni/Co atoms in Ni-Co-P NSs provided abundant catalytic active sites for the electrochemical redox reaction of DA, which exhibited a remarkable consequence with a wide linear range from 0.3~50 μM, a high sensitivity of 2.033 µA µM−1 cm−2, a low limit of detection of 0.016 µM, and anti-interference ability. As a result, the proposed Ni-Co-P NSs can be considered an ideal electrode material for the electrochemical non-enzymatic DA sensing.
Exploring Peripheral Blood-Derived Extracellular Vesicles as Biomarkers: Implications for Chronic Chagas Disease with Viral Infection or Transplantation
Authors: Madeira Rafael Pedro , Meneghetti Paula , Lozano Nicholy , Namiyama Gislene M. , Pereira-Chioccola Vera Lucia , Torrecilhas Ana Claudia
Published: January 2024

Extracellular vesicles (EVs) are lipid bilayer envelopes that encapsulate cell-specific cargo, rendering them promising biomarkers for diverse diseases. Chagas disease, caused by the parasite Trypanosoma cruzi, poses a significant global health burden, transcending its initial epicenter in Latin America to affect individuals in Europe, Asia, and North America. In this study, we aimed to characterize circulating EVs derived from patients with chronic Chagas disease (CCD) experiencing a reactivation of acute symptoms. Blood samples collected in EDTA were processed to isolate plasma and subsequently subjected to ultracentrifugation for particle isolation and purification. The EVs were characterized using a nanoparticle tracking analysis and enzyme-linked immunosorbent assay (ELISA). Our findings revealed distinctive differences in the size, concentration, and composition of EVs between immunosuppressed patients and those with CCD. Importantly, these EVs play a critical role in the pathophysiology of Chagas disease and demonstrate significant potential as biomarkers in the chronic phase of the disease. Overall, our findings support the potential utility of the CL-ELISA assay as a specific sensitive tool for detecting circulating EVs in chronic Chagasic patients, particularly those with recurrent infection following an immunosuppressive treatment or with concurrent HIV and Chagas disease. Further investigations are warranted to identify and validate the specific antigens or biomarkers responsible for the observed reactivity in these patient groups, which may have implications for diagnosis, the monitoring of treatment, and prognosis.
Clustered Regularly Interspaced Short Palindromic Repeat/CRISPR-Associated Protein and Its Utility All at Sea: Status, Challenges, and Prospects
Authors: Li Jiashun , Wu Shuaishuai , Zhang Kaidian , Sun Xueqiong , Lin Wenwen , Wang Cong , Lin Senjie
Published: January 2024

Initially discovered over 35 years ago in the bacterium Escherichia coli as a defense system against invasion of viral (or other exogenous) DNA into the genome, CRISPR/Cas has ushered in a new era of functional genetics and served as a versatile genetic tool in all branches of life science. CRISPR/Cas has revolutionized the methodology of gene knockout with simplicity and rapidity, but it is also powerful for gene knock-in and gene modification. In the field of marine biology and ecology, this tool has been instrumental in the functional characterization of ‘dark’ genes and the documentation of the functional differentiation of gene paralogs. Powerful as it is, challenges exist that have hindered the advances in functional genetics in some important lineages. This review examines the status of applications of CRISPR/Cas in marine research and assesses the prospect of quickly expanding the deployment of this powerful tool to address the myriad fundamental marine biology and biological oceanography questions.
Evaluation of Holmium(III), Erbium(III), and Gadolinium(III) Accumulation by Cyanobacteria Arthrospira platensis Using Neutron Activation Analysis and Elements’ Effects on Biomass Quantity and Biochemical Composition
Authors: Zinicovscaia Inga , Cepoi Liliana , Rudi Ludmila , Chiriac Tatiana , Grozdov Dmitrii
Published: January 2024

Rare-earth elements are released into the aquatic environment as a result of their extensive use in industry and agriculture, and they can be harmful for living organisms. The effects of holmium(III), erbium(III), and gadolinium(III) when added to a growth medium in concentrations ranging from 10 to 30 mg/L on the accumulation ability and biochemical composition of Arthrospira platensis were studied. According to the results of a neutron activation analysis, the uptake of elements by cyanobacteria occurred in a dose-dependent manner. The addition of gadolinium(III) to the growth medium did not significantly affect the amount of biomass, whereas erbium(III) and holmium(III) reduced it up to 22% compared to the control. The effects of rare-earth elements on the content of proteins, carbohydrates, phycobiliproteins, lipids, β carotene, and chlorophyll a were evaluated. The studied elements had different effects on the primary biomolecule content, suggesting that holmium(III) and erbium(III) were more toxic than Gd(III) for Arthrospira platensis.
Different Microeukaryotic Trophic Groups Show Different Latitudinal Spatial Scale Dependences in Assembly Processes across the Continental Shelves of China
Authors: Zhang Yong , Qu Zhishuai , Zhang Kexin , Li Jiqiu , Lin Xiaofeng
Published: January 2024

The relative role of stochasticity versus determinism is critically dependent on the spatial scale over which communities are studied. However, only a few studies have attempted to reveal how spatial scales influence the balance of different assembly processes. In this study, we investigated the latitudinal spatial scale dependences in assembly processes of microeukaryotic communities in surface water and sediment along the continental shelves of China. It was hypothesized that different microeukaryotic trophic groups (i.e., autotroph, heterotroph, mixotroph, and parasite) showed different latitudinal scale dependences in their assembly processes. Our results disclosed that the relative importance of different assembly processes depended on a latitudinal space scale for planktonic microeukaryotes. In surface water, as latitudinal difference increased, the relative contributions of homogenous selection and homogenizing dispersal decreased for the entire community, while those of heterogeneous selection and drift increased. The planktonic autotrophic and heterotrophic groups shifted from stochasticity-dominated processes to heterogeneous selection as latitudinal differences surpassed thresholds of 8° and 16°, respectively. For mixotrophic and parasitic groups, however, the assembly processes were always dominated by drift across different spatial scales. The balance of different assembly processes for the autotrophic group was mainly driven by temperature, whereas that of the heterotrophic group was driven by salinity and geographical distance. In sediment, neither the entire microeukaryotic community nor the four trophic groups showed remarkable spatial scale dependences in assembly processes; they were always overwhelmingly dominated by the drift. This work provides a deeper understanding of the distribution mechanisms of microeukaryotes along the continental shelves of China from the perspective of trophic groups.
Whole Genome Sequencing and Comparative Analysis of the First Ehrlichia canis Isolate in China
Authors: Zhang Jilei , Wang Jiawei , Wang Chengming
Published: January 2024

Ehrlichia canis, a prominent tick-borne pathogen causing canine monocytic ehrlichiosis (CME), is one of the six recognized Ehrlichia species worldwide. Despite its widespread presence in ticks and host dogs in China, comprehensive genomic information about this pathogen remains limited. This study focuses on an in-depth analysis of E. canis YZ-1, isolated and cultured from an infected dog in China. The complete genome of E. canis YZ-1 was sequenced (1,314,789 bp, 1022 genes, 29% GC content, and 73% coding bases), systematically characterizing its genomic elements and functions. Comparative analysis with representative genomes of Ehrlichia species, including E. canis strain Jake, E. chaffeensis, Ehrlichia spp., E. muris, E. ruminantium, and E. minasensis, revealed conserved genes, indicating potential evolutionary connections with E. ruminantium. The observed reduction in virulence-associated genes, coupled with a type IV secretion system (T4SS), suggests an intricate balance between pathogenicity and host adaptation. The close relationship with E. canis Jake and E. chaffeensis, alongside nuanced genomic variations with E. ruminantium and E. mineirensis, underscores the need to explore emerging strains and advancements in sequencing technologies continuously. This genetic insight opens avenues for innovative medications, studies on probiotic resistance, development of new detection markers, and progress in vaccine development for ehrlichiosis. Further investigations into the functional significance of identified genes and their role in host–pathogen interactions will contribute to a more holistic comprehension of Ehrlichia’s biology and its implications for pathogenicity and transmission.
Anti-Cancer and Anti-Oxidant Bioactive Metabolites from Aspergillus fumigatus WA7S6 Isolated from Marine Sources: In Vitro and In Silico Studies
Authors: Hassan Mervat G. , Elmezain Waleed A. , Baraka Dina M. , AboElmaaty Sabah A. , Elhassanein Ahmed , Ibrahim Riyad Mohammed , Hamed Ahmed A.
Published: January 2024

Cancer is a huge global disease burden. Every year, tens of millions of people worldwide are diagnosed with cancer, and more than half of them die as a result of it. The great biodiversity of the marine environment has increasingly piqued the interest of experts, especially in the field of drug discovery. The marine fungus Aspergillus fumigatus WA7S6 has been selected among a group of fungi isolated from marine sponges as it exhibits a pronounced antimicrobial activity toward a group of pathogenic microbes. The fungus has been identified genetically by amplification and analysis of its 18srRNA gene. The fungus crude extract has been obtained by cultivation of the fungus on rice media. The crude extract was tested for antibacterial activity against a variety of pathogenic microorganisms. The results demonstrated a pronounced antimicrobial action against P. aeruginosa, S. aureus, A. niger, and Candida albicans. Furthermore, we tested the antioxidant potential of the Aspergillus fumigatus WA7S6 crude extract using three different methods: ATBS, DPPH, and lipid peroxidation assays. Results showed that the crude extract WA7S6 had an IC50 value of 21.35 µg/mL. The anticancer potential of the crude extract was also evaluated against cancer cell lines such as Hela, MCF, and WI-38. The chemical profiling of the fungus extract was identified via GC-mass and in silico molecular docking of the identified compounds on heme oxygenase, as a stress protein included in cellular protection, antioxidant, and anti-inflammatory activities, suggesting that some compounds, such as 9-Tetradecynoic acid, 11-Hexadecynoic acid, methyl ester, and dehydromevalonic lactone, could be relevant for antioxidant purposes.
Editorial for Special Issue “Bacterial Toxin-Antitoxin Systems”
Authors: Kamruzzaman Muhammad
Published: January 2024

Toxin antitoxin systems (TAS) are widely distributed in bacterial chromosomes as well as on mobile genetic elements [...]
The Middle Miocene Microfacies, Cyclicity, and Depositional History: Implications on the Marmarica Formation at the Siwa Oasis, Western Desert (Egypt)
Authors: Khalifa Mohamed A. , Zaky Amr S. , Jovane Luigi , El-Hewy Ahmed M. , Zahran Esam , Kasem Atef M.
Published: January 2024

Microfacies studies were carried out on the Middle Miocene Marmarica Formation exposed at the Gabal Western Bahi El-Din and Gabal El-Najdeen, the Siwa Oasis, northwestern Desert (Egypt). It was distinguished into the lower, middle, and upper members. Eleven microfacies types were recognized, which include skeletal lime-mudstone, dolomitic lime-mudstone, intraclastic wackestone, bryozoan wackestone, foraminiferal wackestone, foraminiferal bryozoan packstone, glauconitic molluscan packstone, molluscan intraclastic packstone, pelletal peloidal skeletal packstone, dolostones, and claystone microfacies. This formation includes several types of emergence- meter-scale cycles (shallowing-upward). Field observations and petrographic analyses revealed that these cycles consist of pure carbonates and mixed siliciclastic carbonates. These cycles consist of four types of gradual cycles and six types of non-gradual cycles. The gradual emergence cycles indicate a balance between the rate of subsidence, sea level oscillations, and sedimentation rate. The non-gradual cycles indicate an irregular balance between sedimentation rate and subsidence rate. The non-gradual cycles denote high-frequency sea level variation and/or short-term sea level oscillations, which are associated with high carbonate formation. The depositional environments of the Marmarica Formation are restricted to lagoonal at the base, followed upward to open marine conditions. Both environments most probably characterize the platform setting.
An Assessment of Dispersion-Corrected DFT Methods for Modeling Nonbonded Interactions in Protein Kinase Inhibitor Complexes
Authors: Zhu Yan , Alqahtani Saad , Hu Xiche
Published: January 2024

Accurate modeling of nonbonded interactions between protein kinases and their small molecule inhibitors is essential for structure-based drug design. Quantum chemical methods such as density functional theory (DFT) hold significant promise for quantifying the strengths of these key protein–ligand interactions. However, the accuracy of DFT methods can vary substantially depending on the choice of exchange–correlation functionals and associated basis sets. In this study, a comprehensive benchmarking of nine widely used DFT methods was carried out to identify an optimal approach for quantitative modeling of nonbonded interactions, balancing both accuracy and computational efficiency. From a database of 2139 kinase-inhibitor crystal structures, a diverse library of 49 nonbonded interaction motifs was extracted, encompassing CH–π, π–π stacking, cation–π, hydrogen bonding, and salt bridge interactions. The strengths of nonbonded interaction energies for all 49 motifs were calculated at the advanced CCSD(T)/CBS level of theory, which serve as references for a systematic benchmarking of BLYP, TPSS, B97, ωB97X, B3LYP, M062X, PW6B95, B2PLYP, and PWPB95 functionals with D3BJ dispersion correction alongside def2-SVP, def2-TZVP, and def2-QZVP basis sets. The RI, RIJK, and RIJCOSX approximations were used for selected functionals. It was found that the B3LYP/def2-TZVP and RIJK RI-B2PLYP/def2-QZVP methods delivered the best combination of accuracy and computational efficiency, making them well-suited for efficient modeling of nonbonded interactions responsible for molecular recognition of protein kinase inhibitors in their targets.
The Relationship between Depressiveness and Eating Behaviors among Women
Authors: Rachubińska Kamila , Cybulska Anna Maria , Kupcewicz Ewa , Panczyk Mariusz , Ślusarska Barbara , Grochans Elżbieta , Schneider-Matyka Daria
Published: January 2024

(1) The objective of the study was to determine the relationship between depressiveness and the occurrence of eating disorders, i.e., emotional eating, uncontrolled eating, cognitive restraint of eating, and the risk of orthorexia. (2) The study was conducted among 556 women from the West Pomeranian Voivodeship (Poland). The study employed the diagnostic survey method using a questionnaire technique: The Beck Depression Inventory, the ORTO—15 Questionnaire, the Three-Factor Eating Questionnaire, and a sociodemographic questionnaire. (3) Higher depressiveness severity is associated with a higher score on the “Cognitive Restraint of Eating” scale. The authors’ original study demonstrated a statistically significant relationship only between depressiveness and the “Uncontrolled Eating” subscale (p = 0.001). (4) The results of this study suggest that depressiveness is an important factor that contributes to a better understanding of eating behaviors. In addition, the results of this study suggest that eating behaviors and psychological factors should be taken into account in psychological interventions in the treatment of eating disorders. The clinical goal can be considered to be an improvement in non-normative eating behaviors, such as a reduction in overeating episodes or eating less frequently in the absence of a feeling of hunger.
Nutritional Status and Physical Exercise Are Associated with Cognitive Function in Chinese Community-Dwelling Older Adults: The Role of Happiness
Authors: Liu Jianghong , Pan Michael , Sun McKenna , Shi Haoer , Feng Rui
Published: January 2024

We aim to assess the relationship between nutrition status, physical exercise, and cognitive function and particularly examine how happiness modifies and mediates the relationship, among 699 seniors aged 60 and above in Shanghai, China. Linear regression models were used to validate the effects of nutrition and exercise on cognitive function and to test their interaction effects with happiness. When the interactions were significant, stratified analyses in sub-groups were conducted. Mediation effects of happiness were examined using two-step causal mediation models. We confirmed that better nutrition (p < 0.001) and exercise (p = 0.009) were significantly associated with less cognitive decline. Furthermore, the effects of nutrition and exercise on cognitive decline were significant in the unhappy (happiness < 20) (p < 0.001) and younger (age < 74) sub-groups (p = 0.015). Happiness partially mediated 11.5% of the negative association of cognitive decline with nutrition (p = 0.015) and 23.0% of that with exercise (p = 0.017). This study suggests that happiness moderates and partially mediates the effects of exercise and nutrition on cognitive status. The beneficial effects of exercise and nutrition were stronger in less happy or younger seniors. Future intervention studies are required to confirm this path relationship.
Analysis of a Cohort of 165 Pediatric Patients with Human Bocavirus Infection and Comparison between Mono-Infection and Respiratory Co-Infections: A Retrospective Study
Authors: Caporizzi Alice , Ravidà Federica , Barneschi Sara , Moriondo Maria , Nieddu Francesco , Boscia Silvia , Stinco Mariangela , Ricci Silvia , Trapani Sandra
Published: January 2024

Introduction: Human Bocavirus (HBoV) is mainly associated with respiratory tract infections. However, its role as respiratory pathogen is not fully understood for a high co-infection rate in symptomatic patients and a significant HBoV detection rate in asymptomatic subjects. This study aimed to describe a large cohort of children with HBoV infection and to compare HBoV mono-infection and co-infections. Methods: We retrospectively reviewed data from 165 children admitted to Meyer Children’s Hospital IRCCS from March 2022 to March 2023 with the diagnosis of HBoV infection, detected using Reverse Transcription qPCR from nasal swabs. Thereafter, we compared patients with HBoV mono-infection (Group A) and those with HBoV co-infections (Group B) in terms of disease severity, established by the length of stay (LOS), the requirement of Pediatric Intensive Care Unit (PICU), and advanced respiratory support (ARS). Results: The median age was 1.5 years; 80% of patients presented with respiratory symptoms. The discharge rate from the emergency department (ED) within 24 h was 42.4%. Most cases (57.6%) were hospitalized, and 7.3% were admitted to PICU due to respiratory failure. Group A comprised 69 patients, and Group B 96 children (95% viral co-infections, 2% bacterial, 3% viral and bacterial). Group A and Group B were similar in hospitalization rate but differed significantly in LOS (median 3 vs. 5 days) and requirement of PICU admission (0 vs. 12 patients, p < 0.001). Patients with a respiratory disease history (17.5%) showed significantly longer LOS and more necessity of inhaled bronchodilator therapy. Conclusions: HBoV should be considered a relevant respiratory pathogen especially in viral co-infections. Patients with HBoV co-infections have a higher risk of necessitating advanced respiratory support with more PICU admission and longer LOS; a previous respiratory disease puts them at a higher risk of longer hospitalization.
Development of Multienzyme Isothermal Rapid Amplification (MIRA) Combined with Lateral-Flow Dipstick (LFD) Assay to Detect Species-Specific tlh and Pathogenic trh and tdh Genes of Vibrio parahaemolyticus
Authors: Park Seong Bin , Zhang Yan
Published: January 2024

Vibrio parahaemolyticus causes severe gastroenteritis in humans after consuming contaminated raw or undercooked seafood. A species-specific marker, the thermolabile hemolysin (tlh) gene, and two pathogenic markers, thermostable-related hemolysin (trh) and thermostable-direct hemolysin (tdh) genes, have been used to identify V. parahaemolyticus and determine its pathogenicity using both PCR and qPCR assays. To enable testing in field conditions with limited resources, this study aimed to develop a simple and rapid method to detect the species-specific (tlh) and pathogenic (trh and tdh) genes of V. parahaemolyticus using multienzyme isothermal rapid amplification (MIRA) combined with a lateral-flow dipstick (LFD). The amplification of the tlh, trh, and tdh genes could be completed within 20 min at temperatures ranging from 30 to 45 °C (p < 0.05). The test yielded positive results for V. parahaemolyticus but produced negative results for nine Vibrio species and eighteen foodborne pathogenic bacterial species. MIRA-LFD could detect 10 fg of DNA and 2 colony-forming units (CFU) of V. parahaemolyticus per reaction, demonstrating a sensitivity level comparable to that of qPCR, which can detect 10 fg of DNA and 2 CFU per reaction. Both MIRA-LFD and qPCR detected seven tlh-positive results from thirty-six oyster samples, whereas one positive result was obtained using the PCR assay. No positive results for the trh and tdh genes were obtained from any oyster samples using MIRA-LFD, PCR, and qPCR. This study suggests that MIRA-LFD is a simple and rapid method to detect species-specific and pathogenic genes of V. parahaemolyticus with high sensitivity.