bluuebunny/crossref_metadata_2025 huggingface dataset:
Machine Learning Prediction of the Redox Activity of Quinones
Authors: Kichev Ilia , Borislavov Lyuben , Tadjer Alia , Stoyanova Radostina
Published: October 2023

The redox properties of quinones underlie their unique characteristics as organic battery components that outperform the conventional inorganic ones. Furthermore, these redox properties could be precisely tuned by using different substituent groups. Machine learning and statistics, on the other hand, have proven to be very powerful approaches for the efficient in silico design of novel materials. Herein, we demonstrated the machine learning approach for the prediction of the redox activity of quinones that potentially can serve as organic battery components. For the needs of the present study, a database of small quinone-derived molecules was created. A large number of quantum chemical and chemometric descriptors were generated for each molecule and, subsequently, different statistical approaches were applied to select the descriptors that most prominently characterized the relationship between the structure and the redox potential. Various machine learning methods for the screening of prospective organic battery electrode materials were deployed to select the most trustworthy strategy for the machine learning-aided design of organic redox materials. It was found that Ridge regression models perform better than Regression decision trees and Decision tree-based ensemble algorithms.
Correlating the Effect of Composition and Textural Properties on Bioactivity for Pristine and Copper-Doped Binary Mesoporous Bioactive Glass Nanoparticles
Authors: Vergnaud Florestan , Mekonnen Benhur , El Abbassi Abdelouahad , Vichery Charlotte , Nedelec Jean-Marie
Published: October 2023

Multifunctional substitutes for bone tissue engineering have gained significant interest in recent years in the aim to address the clinical challenge of treating large bone defects resulting from surgical procedures. Sol–gel mesoporous bioactive glass nanoparticles (MBGNs) have emerged as a promising solution due to their high reactivity and versatility. The effect of calcium content on MBGNs textural properties is well known. However, the relationship between their composition, textural properties, and reactivity has not yet been thoroughly discussed in existing studies, leading to divergent conclusions. In this study, pristine and copper-doped binary MGBNs were synthesized by a modified Stöber method, using a cationic surfactant as pore-templating agent. An opposite evolution between calcium content (12–26 wt%) and specific surface area (909–208 m2/g) was evidenced, while copper introduction (8.8 wt%) did not strongly affect the textural properties. In vitro bioactivity assessments conducted in simulated body fluid (SBF) revealed that the kinetics of hydroxyapatite (HAp) crystallization are mainly influenced by the specific surface area, while the composition primarily controls the quantity of calcium phosphate produced. The MBGNs exhibited a good bioactivity within 3 h, while Cu-MBGNs showed HAp crystallization after 48 h, along with a controlled copper release (up to 84 ppm at a concentration of 1 mg/mL). This comprehensive understanding of the interplay between composition, textural properties, and bioactivity, offers insights for the design of tailored MBGNs for bone tissue regeneration with additional biological and antibacterial effects.
Revealing the Interface Characteristic and Bonding Ability of CoCrFeNi High Entropy Alloy/Al Composite by First-Principles Calculations
Authors: Liu Yunzi , Gao Yong , Chen Jian
Published: October 2023

In this work, the interfacial atomic bonding process and atom-matching structure of Al atoms deposited on the crystal plane of CoCrFeNi HEA were investigated by first-principles calculations. The relevant physical parameters, including crystal structure, lattice constants, chemical bonding, and differential charge distribution, were studied in detail. The results showed that the constructed crystal model of CoCrFeNi HEA has a stable structure, and the binding energy of Al atoms deposited constantly on different crystal planes at different sites is less than −16.21 eV, indicating a strong interface bonding ability. With the increase in deposited atoms, the material is subjected to a phase transition from two-dimensional chemical adsorption of Al atoms in a single layer to three-dimensional chemical binding of the bulk. Furthermore, the electron cloud occurred through the interaction of positive and negative charges at the interface, indicating that the charge has been transferred along with a chemical bond between Al and CoCrFeNi atoms. It can be thought that the interface formed a stable structure and possessed low mismatch stress. This work provides a theoretical basis for designing CoCrFeNi series HEA-reinforced Al matrix composites.
Fe-Co Alloy Nanoparticles Dispersed in Polymer-Derived Carbon Support: Effect of Initial Polymer Nature on the Size, Structure and Magnetic Properties
Authors: Vasilev Andrey , Efimov Mikhail , Muratov Dmitry , Chernavskii Petr , Cherednichenko Kirill , Dzidziguri Ella , Karpacheva Galina
Published: October 2023

Fe-Co alloy nanoparticles with different sizes, supported by carbon derived from several polymers, namely polyacrylonitrile, polyvinyl alcohol and chitosan, have been synthesized by a one-pot method involving simultaneous metal nanoparticle formation and polymer carbonization. The method involves the joint dissolution of metal salts and a polymer, followed by annealing of the resulting dried film. Detailed XRD analysis confirmed the formation of Fe-Co alloy nanoparticles in each sample, regardless of the initial polymer used. Transmission electron microscopy images showed that the Fe-Co nanoparticles were all spherical, were homogeneously distributed within the carbon support and varied by size depending on the initial polymer nature and synthesis temperature. Fe-Co nanoparticles supported by polyacrylonitrile-derived carbon exhibited the smallest size (6–12 nm), whereas nanoparticles on chitosan-derived carbon support were characterized by the largest particle size (13–38 nm). The size dependence of magnetic properties were studied by a vibrating sample magnetometer at room temperature. For the first time, the critical particle size of Fe-Co alloy nanoparticles with equiatomic composition has been experimentally determined as 13 nm, indicating the transition of magnetic properties from ferromagnetic to superparamagnetic.
Bond-Graph-Based Approach to Teach PID and Sliding Mode Control in Mechatronics
Authors: Guo Zenan , Korondi Péter , Szemes Péter Tamás
Published: October 2023

The main contribution of this article is creating synergy between subjects; this means that students use the same graphical tool in several subjects. So far, the bond graph has not been used in control theory, but it is the “native language” of mechatronics engineers, so we would like to introduce it into the teaching of control theory. The bond graph method is proposed as a novel teaching method to teach mechatronics subjects in the paper. The bond graph is a graphical alternative to ordinary differential equations from a mathematical standpoint. Traditionally, control theory employs ordinary differential equations, as they are familiar to control theorists. However, mathematically, both approaches are equivalent but require a slightly different approach in their application. This article highlights the mathematical similarities between the two approaches while emphasizing the distinctions in graphical representation. Another contribution is that the PID and sliding mode controller are represented using the bond graph method. In the meantime, through the use of practical examples, we effectively illustrate how the same problem can be solved using either approach. In the training materials, the PID controller and an adaptive robust sliding mode controller (ARSMC) with the bond graph are utilized as examples to demonstrate synergy in mechatronics. Finally, we present proof that mechatronic engineers achieve superior outcomes when utilizing the bond graph approach, based on test results from undergraduate students.
Generalized Minkowski Type Integral Formulas for Compact Hypersurfaces in Pseudo-Riemannian Manifolds
Authors: Alessa Norah , Guediri Mohammed
Published: October 2023

We obtain some generalized Minkowski type integral formulas for compact Riemannian (resp., spacelike) hypersurfaces in Riemannian (resp., Lorentzian) manifolds in the presence of an arbitrary vector field that we assume to be timelike in the case where the ambient space is Lorentzian. Some of these formulas generalize existing formulas in the case of conformal and Killing vector fields. We apply these integral formulas to obtain interesting results concerning the characterization of such hypersurfaces in some particular cases such as when the ambient space is Einstein admitting an arbitrary (in particular, conformal or Killing) vector field, and when the hypersurface has a constant mean curvature.
Effects of LTNE on Two-Component Convective Instability in a Composite System with Thermal Gradient and Heat Source
Authors: Balaji Varalakshmi K. , Narayanappa Manjunatha , Udhayakumar Ramalingam , AlNemer Ghada , Ramakrishna Sumithra , Honnappa Gangadharaih Yeliyur
Published: October 2023

An analytical study is conducted to examine the influence of thermal gradients and heat sources on the onset of two-component Rayleigh–Bènard (TCRB) convection using the Darcy model. The study takes into account the effects of local thermal non-equilibrium (LTNE), thermal profiles, and heat sources. The composite structure is horizontally constrained by adiabatic stiff boundaries, and the resulting solution to the problem is obtained using the perturbation approach. The various physical parameters have been thoroughly examined, revealing that the fluid layer exhibits dominance in the two-layer configuration. It has been observed that the parabolic profile demonstrates greater stability in comparison to the step function. Conversely, in the setup where the porous layer dominates, the step function plays a crucial role in maintaining stability. The porous layer, model (iv), exhibits greater stability in the predominant combined structure, while the linear configuration is characterized by higher instability.
A Broad TSK Fuzzy Classifier with a Simplified Set of Fuzzy Rules for Class-Imbalanced Learning
Authors: Zhang Jinghong , Li Yingying , Liu Bowen , Chen Hao , Zhou Jie , Yu Hualong , Qin Bin
Published: October 2023

With the expansion of data scale and diversity, the issue of class imbalance has become increasingly salient. The current methods, including oversampling and under-sampling, exhibit limitations in handling complex data, leading to overfitting, loss of critical information, and insufficient interpretability. In response to these challenges, we propose a broad TSK fuzzy classifier with a simplified set of fuzzy rules (B-TSK-FC) that deals with classification tasks with class-imbalanced data. Firstly, we select and optimize fuzzy rules based on their adaptability to different complex data to simplify the fuzzy rules and therefore improve the interpretability of the TSK fuzzy sub-classifiers. Secondly, the fuzzy rules are weighted to protect the information demonstrated by minority classes, thereby improving the classification performance on class-imbalanced datasets. Finally, a novel loss function is designed to derive the weights for each TSK fuzzy sub-classifier. The experimental results on fifteen benchmark datasets demonstrate that B-TSK-FC is superior to the comparative methods from the aspects of classification performance and interpretability in the scenario of class imbalance.
On an Extension of a Spare Regularization Model
Authors: Moudafi Abdellatif
Published: October 2023

In this paper, we would first like to promote an interesting idea for identifying the local minimizer of a non-convex optimization problem with the global minimizer of a convex optimization one. Secondly, to give an extension of their sparse regularization model for inverting incomplete Fourier transforms introduced. Thirdly, following the same lines, to develop convergence guaranteed efficient iteration algorithm for solving the resulting nonsmooth and nonconvex optimization problem but here using applied nonlinear analysis tools. These both lead to a simplification of the proofs and to make a connection with classical works in this filed through a startling comment.
Estimation and Inference for Spatio-Temporal Single-Index Models
Authors: Wang Hongxia , Zhao Zihan , Hao Hongxia , Huang Chao
Published: October 2023

To better fit the actual data, this paper will consider both spatio-temporal correlation and heterogeneity to build the model. In order to overcome the “curse of dimensionality” problem in the nonparametric method, we improve the estimation method of the single-index model and combine it with the correlation and heterogeneity of the spatio-temporal model to obtain a good estimation method. In this paper, assuming that the spatio-temporal process obeys the α mixing condition, a nonparametric procedure is developed for estimating the variance function based on a fully nonparametric function or dimensional reduction structure, and the resulting estimator is consistent. Then, a reweighting estimation of the parametric component can be obtained via taking the estimated variance function into account. The rate of convergence and the asymptotic normality of the new estimators are established under mild conditions. Simulation studies are conducted to evaluate the efficacy of the proposed methodologies, and a case study about the estimation of the air quality evaluation index in Nanjing is provided for illustration.
A Prospective Study on the Impact of Clinical Factors and Adjusted Triple D System for Success Rate of ESWL
Authors: Snicorius Marius , Drevinskaitė Mingailė , Miglinas Marius , Čekauskas Albertas , Urbonienė Vidita , Bandzevičiūtė Rimantė , Čeponkus Justinas , Šablinskas Valdas , Želvys Arunas
Published: October 2023

Objective: Our study aimed to evaluate the success rate of ESWL and identify relevant treatment-specific factors affecting treatment outcomes, as well as to assess the accuracy of the updated Triple D scoring system and compare it with older systems. Material and Methods: A prospective study of 71 patients who received ESWL treatment for renal stones that were 5–15 mm in size was completed. The patient having no residual stones or residual stones lesser than 4 mm after ESWL was identified as a treatment success. Univariate and multivariate logistic regression and ROC curves were used to identify important factors for treatment outcomes. Results: Successful treatment was achieved for 66.2% of patients. The stone volume (SV), mean stone density (MD), and delivered power to the stone volume unit ratio (SMLI/SV) were defined as the most critical factors influencing ESWL success. An updated Triple D score system with a, SMLI/SV ratio could be an alternative to older systems and reach an even higher accuracy. A limitation of this study is the limited sample size due to the COVID-19 pandemic. Conclusions: Our results show that the three factors that most influence the success of ESWL are the stone size, mean stone density, and SMLI/SV ratio. Based on this, we present a simple updated triple D score system to predict ESWL success, which could be implemented in future clinical practice.
Bacterial Infection of an Alveolar Echinococcus Cyst from C. perfringens Septicemia: A Case Report and Review of the Literature
Authors: Buttenschoen Jonas , Pavel Vlad , Mehrl Alexander , Michels Bernhard , Albaladejo Fuertes Sheila , Seydel Bettina , Schlosser-Hupf Sophie , Müller Martina , Schmid Stephan
Published: October 2023

Background and Objectives: Alveolar echinococcosis (AE) is a highly variable disease able to present as structurally diverse cysts in different organs based on the host’s immunological state as well as the time between diagnosis and the primary infection. Bacterial superinfections, especially with anaerobic pathogens from the Clostridiaceae genus, can further alter the radiological findings due to pneumobilia, newly formed abscess formations, and inflammatory changes. Materials and Methods: We present a case of a 71-year-old Caucasian male admitted to our intensive care unit with septic shock, pneumobilia, and a complex cyst of the liver with calcification, as shown by an initial CT. Because of the septic shock, the patient was started on broad-band antibiotics. Clostridiaceae infection was considered an important differential diagnosis due to the presence of pneumobilia observed in the initial CT, without a history of previous endoscopy. Furthermore, serology for echinococcus was positive, and blood cultures showed growth of C. perfringens. Therefore, the patient was additionally treated with albendazole. After recovery, further staging was conducted, showing complete remission of the cyst and a left-over lesion classified as Alveolar Echinococcosis Ulm Classification (AEUC) V. In summary, the patient had a pre-existing, controlled AE infection that became superinfected with C. perfringens, likely attributable to the anaerobic necrotic tissue, leading to septicemia. Results: The anaerobic tissue within the AE cyst provided an ideal medium for C. perfringens to replicate, leading to cyst infection, which subsequently caused septic shock and pneumobilia. The initial findings from CT and MRI were confounded by the superinfection, demonstrating the diagnostic challenges of AE, especially when presenting with complications. Conclusions: Diagnosing AE remains a demanding task, even with the excellent tools available through serology, coupled with CT, FDG-PET-CT, and MRI. Notably, older superinfected cysts can pose difficulties when integrated into the appropriate diagnostic context. Prompt diagnosis is critical for the accurate treatment of echinococcosis and its complications, such as bacterial superinfections. From a clinical perspective, septicemia from Clostridiaceae and infections with C. perfringens—pathogens capable of inducing pneumobilia—should be regarded as significant differential diagnoses for pneumobilia in the absence of a recent history of endoscopy.
Correlation of the OCT Double-Layer Sign with Type 1 Non-Exudative Neovascularization on OCT-A in Age-Related Macular Degeneration
Authors: Ristic Dragana , Resan Mirko , Pancevski Igor , Ristic Petar , Vukosavljevic Miroslav , Cvetkovic Milos , Pajic Bojan
Published: October 2023

Background and Objectives: Early diagnosis of the exudative form of age-related macular degeneration (AMD) is very important for a timely first treatment, which is directly related to the preservation of functional visual acuity over a long period. The goal of this paper was to examine the correlation between the double-layer sign (DLS) and the presence of non-exudative macular neovascularization (MNV). Materials and Methods: Our research included 60 patients with AMD, exudative in one eye and non-exudative in the other eye. We analyzed only the non-exudative form using optical coherence tomography (OCT) and optical coherence tomography angiography (OCT-A). The patients were classified into three groups, depending on the duration of the disease (<2 years, 2 to 5 years, >5 years). The onset of the disease was deemed the moment of establishing a diagnosis of exudative AMD in one eye. We defined the presence or absence of a DLS using OCT and the presence of non-exudative MNV using OCT-A, both on 3 × 3 mm and 6 × 6 mm sections. DLS was used as a projection biomarker for non-exudative MNV, with the aim of establishing a rapid diagnosis and achieving early treatment of the disease. Results: We found that there was a statistically significant correlation between the DLS diagnosed using OCT and non-exudative MNV diagnosed by OCT-A for both 3 × 3 mm (p < 0.001) and 6 × 6 mm (p < 0.001) imaging. There was a statistically significant difference between the frequencies of both DLS and MNV in Groups I and III on both 3 × 3 and 6 × 6 mm imaging. A statistically significant difference was also noted in the frequencies of DLS and MNV on 6 × 6 mm imaging, but not on 3 × 3 mm imaging, between Groups I and II. No differences were found between the frequencies of DLS and MNV between Groups II and III. Conclusions: The DLS on OCT can be used as a projection biomarker to assess the presence of a non-exudative MNV.
Cluster Analysis of Subjective Shoulder Stiffness and Muscle Hardness: Associations with Central Sensitization-Related Symptoms
Authors: Komoto Natsuna , Sakebayashi Hanako , Imagawa Naoto , Mizuno Yuji , Nakata Ibuki , Shigetoh Hayato , Kodama Takayuki , Miyazaki Junya
Published: October 2023

Background and Objectives: Understanding the relationships between subjective shoulder stiffness, muscle hardness, and various factors is crucial. Our cross-sectional study identified subgroups of shoulder stiffness based on symptoms and muscle hardness and investigated associated factors. Materials and Methods: measures included subjective stiffness, pain, muscle hardness, and factors like physical and psychological conditions, pressure pain threshold, postural alignment, heart rate variability, and electroencephalography in 40 healthy young individuals. Results: Three clusters were identified: Cluster 1 with high stiffness, pain, and muscle hardness; Cluster 2 with low stiffness and pain but high muscle hardness; and Cluster 3 with low levels of all factors. Cluster 1 had significantly higher central sensitization-related symptoms (CSS) scores than Cluster 2. Subjective stiffness is positively correlated with psychological factors. Conclusions: our results suggest that CSS impacts subjective symptom severity among individuals with similar shoulder muscle hardness.
Comparison of the Magnesiothermic Reduction Behavior of Nb2O5 and Ti2Nb10O29
Authors: Hong Jiwon , Hwang Seonmin , Kang Namhyun , Lee Dongwon
Published: October 2023

Nb-Ti binary alloys are widely employed as high value-added materials in the manufacture of super heat-resistant alloys, biomaterials, and superconductors. Therefore, there is significant interest to produce Nb-Ti master alloys in a cost-effective manner. In this study, we investigated the magnesiothermic reduction of Nb2O5 and Ti2Nb10O29 over the temperature range of 1073 to 1223 K and comparatively evaluated the reaction outcomes. The reduction product was composed of metal (Nb or Nb-Ti) particles and MgO, which covered the surface of the reduced metal particles. After the reduction reaction, the surface MgO phase was removed by pickling with hydrochloric acid (HCl) to finally recover the Nb metal or Nb-Ti alloy as a pure product. Scanning electron microscopy and X-ray diffraction analyses of the pure Nb metal and Nb-Ti alloy powders revealed that the reduction of both raw materials was successful at temperatures exceeding 1173 K. Reaction kinetics analysis revealed that the activation energy for the reduction of the mixed metal oxide (Ti2Nb10O29) is lower than that of Nb2O5 reduction. This is because of the different reaction mechanism behaviors during reduction and the different thermodynamic stabilities of the precursors.
Computed Tomography Attenuation of Three-Dimensional (3D) Printing Materials—Depository to Aid in Constructing 3D-Printed Phantoms
Authors: Kalidindi Yuktesh , Ganapathy Aravinda , Nayak Yash , Elumalai Anusha , Chen David , Bishop Grace , Sanchez Adrian , Albers Brian , Shetty Anup , Ballard David
Published: October 2023

Three-dimensionally printed phantoms are increasingly used in medical imaging and research due to their cost-effectiveness and customizability, offering valuable alternatives to commercial phantoms. The purpose of this study was to assess the computed tomography (CT) attenuation characteristics of 27 resin materials from Formlabs, a 3D printing equipment and materials manufacturer. Cube phantoms (both solid and hollow constructions) produced with each resin were subjected to CT scanning under varying tube current–time products with attenuation measurements recorded in Hounsfield units (HU). The resins exhibited a wide range of attenuation values (−3.33 to 2666.27 HU), closely mimicking a range of human tissues, from fluids to dense bone structures. The resins also demonstrated consistent attenuation regardless of changes in the tube current. The CT attenuation analysis of FormLabs resins produced an archive of radiological imaging characteristics of photopolymers that can be utilized to construct more accurate tissue mimicking medical phantoms and improve the evaluation of imaging device performance.
Designed Structures of Interdigital Electrodes for Thin Film SAW Devices
Authors: Qian Yicong , Shuai Yao , Wu Chuangui , Luo Wenbo , Pan Xinqiang , Zhang Wanli
Published: October 2023

This paper studied the impact of the microstructure of interdigital electrodes on the performance of surface acoustic wave (SAW) resonators and proposed an innovative piston, dummy finger and tilt (PDT) structure, which was then applied to the GLONASS L3 band filters. Through the adoption of 3D finite element simulation (FEM), photolithography, and testing on an incredible high-performance surface acoustic wave (I.H.P. SAW) substrate, it is concluded that the total aperture length is 20T (T is period), resulting in a more optimal resonator performance; changing the width and length of the piston can suppress transverse modes spurious, but it does not enhance impedance ratio; to further improve the quality of the SAW resonator, the proposed PDT structure has been experimentally proven to not only effectively suppress transverse modes spurious but also possess a high impedance ratio. By utilizing a PDT structure within a “T + π” topology circuit, we successfully designed and manufactured a GLONASS L3 band filter with a bandwidth of 8 MHz and an insertion loss of 3.73 dB. The design of these resonators and filters can be applied to the construction of SAW filters in similar frequency bands such as BeiDou B2 band or GPS L2/L5 band.
Optimization of the Morphology of the Removal Function for Rotating Abrasive Water Jet Polishing
Authors: Tie Guipeng , Zhang Zhiqiang , Wang Bo , Song Ci , Shi Feng , Zhang Wanli , Si Hailun
Published: October 2023

Abrasive water jet polishing has significant advantages in the manufacturing of complex optical components (such as high-slope optical component cavities) that require high-precision manufacturing. This is due to its processing process, in which the polishing tool does not make direct contact with the surface of the workpiece, and instead maintains a considerable distance. However, the removal functions of most existing abrasive water-jet polishing technologies do not possess strict symmetry, which significantly impacts the ability to correct surface figure errors. Therefore, this study implements rotating abrasive water-jet polishing based on traditional abrasive water jet processing to optimize the removal function, which turns it into a Gaussian form; thus, obtaining a type of removal function more suitable for CCOS polishing. This paper derives an empirical formula between the distance s’ from the peak removal point of the removal function to the stagnation point and the nozzle tilt angle α, based on geometric relationships and experimental results, analyzes the relationship between material removal efficiency, nozzle tilt angle, and standoff distance. Finally, this paper verifies through experiments the validity of this empirical formula under different process parameters. Therefore, this study obtains the process conditions that allow rotating abrasive water-jet polishing technology to achieve a stable Gaussian form removal function, and the appropriate process parameters to be selected in conjunction with polishing efficiency; thereby, effectively improving the removal function’s corrective ability and manufacturing efficiency. It provides theoretical support for the processing capability and process parameter selection of abrasive water-jet polishing technology, solves the problem of limited shaping capability of existing abrasive water jet tools, and significantly improves the manufacturing capability of high-end optical components.
A Uniform Design Method Can Optimize the Combinatorial Parameters of Antimicrobial Photodynamic Therapy, Including the Concentrations of Methylene Blue and Potassium Iodide, Light Dose, and Methylene Blue’s Incubation Time, to Improve Fungicidal Effects on Candida Species
Authors: Du Meixia , Li Feng , Hu Yanwei
Published: October 2023

The optimal combinatorial parameters of antimicrobial photodynamic therapy (aPDT) mediated by methylene blue (MB) with the addition of potassium iodide (KI) against Candida species have never been defined. This study aimed to optimize the combinatorial parameters of aPDT, including the concentrations of MB (X1, 0.1–1.0 mM) and KI (X2, 100–400 mM), light dose (X3, 10–70 J/cm2), and MB’s incubation time (X4, 5–35 min) for three Candida species. The best MB + KI-aPDT fungicidal effects (Y) against Candida albicans ATCC 90028 (YCa), Candida parapsilosis ATCC 22019 (YCp), and Candida glabrata ATCC 2950 (YCg) were investigated using a uniform design method. The regression models deduced using this method were YCa = 7.126 + 1.199X1X3 − 1.742X12 + 0.206X22 − 0.361X32; YCp = 10.724 − 0.867X1 − 1.497X2 + 0.560X3 + 1.298X22; and YCg = 0.892 − 0.956X1 + 2.296X3 + 1.299X42 − 3.316X3X4. The optimal combinatorial parameters inferred from the regression equations were MB 0.1 mM, KI 400 mM, a light dose of 20 J/cm2, and a 5-minute incubation time of MB for Candida albicans; MB 0.1 mM, KI 400 mM, a light dose of 70 J/cm2, and a 5-minute incubation time of MB for Candida parapsilosis; MB 0.1 mM, KI 100 mM, a light dose of 10 J/cm2, and a 35-minute incubation time of MB for Candida glabrata. The uniform design method can optimize the combinatorial parameters of aPDT mediated by MB plus KI to obtain the best aPDT fungicidal effects on Candida species, providing a new method to optimize the combinatorial parameters of aPDT for different pathogens in the future.
Short-Term Effects of Climate Change on Planktonic Heterotrophic Prokaryotes in a Temperate Coastal Lagoon: Temperature Is Good, Ultraviolet Radiation Is Bad, and CO2 Is Neutral
Authors: Barbosa Ana B. , Mosley Benjamin A. , Galvão Helena M. , Domingues Rita B.
Published: October 2023

Planktonic heterotrophic prokaryotes (HProks) are a pivotal functional group in marine ecosystems and are highly sensitive to environmental variability and climate change. This study aimed to investigate the short-term effects of increasing carbon dioxide (CO2), ultraviolet radiation (UVR), and temperature on natural assemblages of HProks in the Ria Formosa coastal lagoon during winter. Two multi-stressor microcosm experiments were used to evaluate the isolated and combined effects of these environmental changes on HProk abundance, production, growth, and mortality rates. The isolated and combined effects of increased CO2 on HProks were not significant. However, HProk production, cellular activity, instantaneous growth rate, and mortality rate were negatively influenced by elevated UVR and positively influenced by warming. Stronger effects were detected on HProk mortality in relation to specific growth rate, leading to higher HProk net growth rates and abundance under elevated UVR and lower values under warming conditions.
Modified Diglycolamide Resin: Characterization and Potential Application for Rare Earth Element Recovery
Authors: Romero Junnile L. , Tabelin Carlito Baltazar , Park Ilhwan , Alorro Richard D. , Zoleta Joshua B. , Silva Leaniel C. , Arima Takahiko , Igarashi Toshifumi , Mhandu Takunda , Ito Mayumi , Happel Steffen , Hiroyoshi Naoki , Resabal Vannie Joy T.
Published: October 2023

Rare earth elements (REEs) are crucial for green energy applications due to their unique properties, but their extraction poses sustainability challenges because the global supply of REEs is concentrated in a few countries, particularly China, which produces 70% of the world’s REEs. To address this, the study investigated TK221, a modified extraction chromatographic resin featuring diglycolamide (DGA) and carbamoyl methyl phosphine oxide (CMPO), as a promising adsorbent for REE recovery. The elemental composition and functional groups of DGA and CMPO on the polystyrene-divinylbenzene (PS-DVB) support of TK221 were confirmed using scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), and X-ray photoelectron spectroscopy (XPS). The adsorption kinetics of neodymium (Nd), yttrium (Y), cerium (Ce), and erbium (Er) followed the pseudo-second-order kinetic model and Langmuir isotherm, indicating monolayer chemisorption. Furthermore, iron (Fe) adsorption reached apparent equilibrium after 360 min, with consistent Fe adsorption observed at both 360 min and 1440 min. The inclusion of Fe in the study is due to its common presence as an impurity in most REE leachate solutions. The Fe adsorption isotherm results are better fitted with the Langmuir isotherm, implying chemisorption. Maximum adsorption capacities (qmax) of the resin were determined as follows: Nd (45.3 mg/g), Ce (43.1 mg/g), Er (35.1 mg/g), Y (15.6 mg/g), and Fe (12.3 mg/g). ATR-FTIR analysis after adsorption suggested that both C=O and P=O bands shifted from 1679 cm−1 to 1618 cm−1 and 1107 cm−1 to 1142 cm−1 for Y, and from 1679 cm−1 to 1607 cm−1 and 1107 cm−1 to 1135 cm−1 for Ce, implying possible coordination with REEs. These results suggest that TK221 has a huge potential as an alternative adsorbent for REE recovery, thus contributing to sustainable REE supply diversification.
Design, Synthesis, and Antifungal Activity of Some Novel Phenylthiazole Derivatives Containing an Acylhydrazone Moiety
Authors: Tian Yao , Shi Jinchao , Deng Xiaoqian , Yu Tingyu , Hu Yong , Hu Richa , Lei Yufeng , Yu Linhua , Zhu Xiang , Li Junkai
Published: October 2023

Crop fungal diseases pose a serious threat to global crop production and quality. Developing new and efficient fungicides is an important measure to control crop diseases. Phenylthiazole was found to be an excellent antifungal skeleton based on our previous study on the structural optimization and biological activity of the natural product thiasporine A. To find new fungicides, 45 phenylthiazole derivatives containing an acylhydrazone moiety were designed and synthesized by the principle of active substructure splicing. Forty-two of the forty-five compounds are novel, except for compounds E1, E14, and E33. Their structures were structurally characterized by 1H NMR, 13C NMR, and HRMS. The antifungal activities of the target compounds against Magnaporthe oryzae Colletotrichum camelliaet, Bipolaris maydis, and Sclerotinia sclerotiorum were evaluated at 25 μg/mL. The bioassay results revealed that most of these compounds exhibited excellent antifungal activities against M. oryzae and C. camelliaet at 25 μg/mL. In particular, compounds E4, E10, E14, E17, E23, E26, and E27 showed the inhibition rate of more than 80% against M. oryzae, with EC50 values of 1.66, 2.01, 2.26, 1.45, 1.50, 1.29, and 2.65 μg/mL, respectively, which were superior to that of the commercial fungicides Isoprothiolane (EC50 = 3.22 μg/mL) and Phenazine-1-carboxylic acid (EC50 = 27.87 μg/mL). The preliminary structure–activity relationship (SAR) results suggested that introducing methyl, halogen, or methoxy at the ortho-position of R1 and the para-position of R2 can endow the final structure with excellent antifungal activity against M. oryzae. The current results provide useful data for developing phenylthiazole derivatives as new fungicides for controlling rice blast caused by M. oryzae.
A Bidens pilosa L. Non-Polar Extract Modulates the Polarization of Human Macrophages and Dendritic Cells into an Anti-Inflammatory Phenotype
Authors: Rodríguez Mesa Xandy Melissa , Contreras Bolaños Leonardo Andres , Modesti Costa Geison , Mejia Antonio Luis , Santander González Sandra Paola
Published: October 2023

Different communities around the world traditionally use Bidens pilosa L. for medicinal purposes, mainly for its anti-inflammatory, antinociceptive, and antioxidant properties; it is used as an ingredient in teas or herbal medicines for the treatment of pain, inflammation, and immunological disorders. Several studies have been conducted that prove the immunomodulatory properties of this plant; however, it is not known whether the immunomodulatory properties of B. pilosa are mediated by its ability to modulate antigen-presenting cells (APCs) such as macrophages (MØs) and dendritic cells (DCs) (through polarization or the maturation state, respectively). Different polar and non-polar extracts and fractions were prepared from the aerial part of B. pilosa. Their cytotoxic and immunomodulatory effects were first tested on human peripheral blood mononuclear cells (PBMCs) and phytohemagglutinin (PHA)-stimulated PBMCs, respectively, via an MTT assay. Then, the non-cytotoxic plant extracts and fractions that showed the highest immunomodulatory activity were selected to evaluate their effects on human MØ polarization and DC maturation (cell surface phenotype and cytokine secretion) through multiparametric flow cytometry. Finally, the chemical compounds of the B. pilosa extract that showed the most significant immunomodulatory effects on human APCs were identified using gas chromatography coupled with mass spectrometry. The petroleum ether extract and the ethyl acetate and hydroalcoholic fractions obtained from B. pilosa showed low cytotoxicity and modulated the PHA-stimulated proliferation of PBMCs. Furthermore, the B. pilosa petroleum ether extract induced M2 polarization or a hybrid M1/M2 phenotype in MØs and a semi-mature status in DCs, regardless of exposure to a maturation stimulus. The immunomodulatory activity of the non-polar (petroleum ether) extract of B. pilosa on human PBMC proliferation, M2 polarization of MØs, and semi-mature status in DCs might be attributed to the low–medium polarity components in the extract, such as phytosterol terpenes and fatty acid esters.
Superb Li-Ion Storage of Sn-Based Anode Assisted by Conductive Hybrid Buffering Matrix
Authors: Shin Jinsil , Park Sung-Hoon , Hur Jaehyun
Published: October 2023

Although Sn has been intensively studied as one of the most promising anode materials to replace commercialized graphite, its cycling and rate performances are still unsatisfactory owing to the insufficient control of its large volume change during cycling and poor electrochemical kinetics. Herein, we propose a Sn-TiO2-C ternary composite as a promising anode material to overcome these limitations. The hybrid TiO2-C matrix synthesized via two-step high-energy ball milling effectively regulated the irreversible lithiation/delithiation of the active Sn electrode and facilitated Li-ion diffusion. At the appropriate C concentration, Sn-TiO2-C exhibited significantly enhanced cycling performance and rate capability compared with its counterparts (Sn-TiO2 and Sn-C). Sn-TiO2-C delivers good reversible specific capacities (669 mAh g−1 after 100 cycles at 200 mA g−1 and 651 mAh g−1 after 500 cycles at 500 mA g−1) and rate performance (446 mAh g−1 at 3000 mA g−1). The superiority of Sn-TiO2-C over Sn-TiO2 and Sn-C was corroborated with electrochemical impedance spectroscopy, which revealed faster Li-ion diffusion kinetics in the presence of the hybrid TiO2-C matrix than in the presence of TiO2 or C alone. Therefore, Sn-TiO2-C is a potential anode for next-generation Li-ion batteries.
Ag Nanocluster Production through DC Magnetron Sputtering and Inert Gas Condensation: A Study of Structural, Kelvin Probe Force Microscopy, and Optical Properties
Authors: Musa Ishaq , Qamhieh Naser , Mahmoud Saleh T.
Published: October 2023

Silver nanoclusters are valuable for a variety of applications. A combination of direct current (DC) magnetron sputtering and inert gas condensation methods, employed within an ultra-high vacuum (UHV) system, was used to generate Ag nanoclusters with an average size of 4 nm. Various analytical techniques, including Scanning Probe Microscopy (SPM), X-ray Diffraction (XRD), Kelvin Probe Force Microscopy (KPFM), UV-visible absorption, and Photoluminescence, were employed to characterize the produced Ag nanoclusters. AFM topographic imaging revealed spherical nanoparticles with sizes ranging from 3 to 6 nm, corroborating data from a quadrupole mass filter (QMF). The XRD analysis verified the simple cubic structure of the Ag nanoclusters. The surface potential was assessed using KPFM, from which the work function was calculated with a reference highly ordered pyrolytic graphite (HOPG). The UV-visible absorption spectra displayed peaks within the 350–750 nm wavelength range, with a strong absorption feature at 475 nm. Additionally, lower excitation wavelengths resulted in a sharp peak emission at 370 nm, which became weaker and broader when higher excitation wavelengths were used.
Poincaré–Chetaev Equations in Dirac’s Formalism of Constrained Systems
Authors: Deriglazov Alexei A.
Published: October 2023

We single out a class of Lagrangians on a group manifold, for which one can introduce non-canonical coordinates in the phase space, which simplify the construction of the Poisson structure without explicitly calculating the Dirac bracket. In the case of the SO(3) manifold, the application of this formalism leads to the Poincaré–Chetaev equations. The general solution to these equations is written in terms of an exponential of the Hamiltonian vector field.
The Effect of Subinhibitory Concentration of Metronidazole on the Growth and Biofilm Formation on Toxigenic Clostridioides difficile Strains Belonging to Different Ribotypes
Authors: Wultańska Dorota , Karpiński Paweł , Piotrowski Michał , Pituch Hanna
Published: October 2023

Clostridioides difficile is a predominant nosocomial pathogen within the healthcare setting able to produce biofilms. Sub-minimum inhibitory concentrations (sub-MICs) of antibiotics trigger mechanisms affecting bacterial virulence, including increased adhesion and biofilm formation. The aim of this study was to investigate how sub-MICs of metronidazole affect the biofilm formation of C. difficile strains. We tested 14 reference and clinical C. difficile strains, including hypervirulent strains of RT027. The MICs of metronidazole for the tested strains were determined using the broth microdilution method. Biofilm formation was evaluated using confocal laser scanning microscopy. The C. difficile strains belonging to RT027 produced the highest amounts of biofilm. The results of confocal laser scanning microscopy showed that all the tested C. difficile strains developed larger biofilms with diversified architectures upon exposure to sub-MICs of metronidazole. In our study, we reveal that sub-MIC concentrations of metronidazole affect the biofilm formation of clinical and reference strains of C. difficile. Importantly, metronidazole induces biofilm formation via hypervirulent RT027 strains.
Designing and Exploration of the Biological Potentials of Novel Centrosymmetric Heteroleptic Copper(II) Carboxylates
Authors: Viola  , Muhammad Niaz , Noor Awal , Sirajuddin Muhammad , Kubicki Maciej , Rahim Shahnaz , Samad Abdus , Shujah Shaukat , Wadood Abdul , Ali Saqib
Published: October 2023

Copper(II) complexes with a general formula [Cu2(3,4-F2C6H3CH2COO)4(L)2], where L = 2-methylpyridine (1) and 3-methylpyridine (2), are reported here. The FTIR spectra of the complexes confirmed the bridging bidentate coordination mode of the carboxylate ligand. The low (475 and 449 cm−1) and strong (727 & 725 cm−1) intensity bands in the FTIR spectra, due to Cu-N stretches and pyridyl ring vibrations, confirmed coordination of the 2-/3-methyl pyridine co-ligands in complexes 1 and 2, respectively. A binuclear paddlewheel structural arrangement with a square pyramidal geometry was confirmed for copper atoms in the complexes via single-crystal X-ray analysis. The DPPH, •OH radical, and α-amylase enzyme inhibition assays showed higher activities for the complexes than for the free ligand acid. The binding constant (Kb = 1.32 × 105 for 1 and 5.33 × 105 for 2) calculated via UV-VIS absorption measurements and docking scores (−6.59 for 1 and −7.43 for 2) calculated via molecular docking showed higher SS-DNA binding potential for 2 compared to 1. Viscosity measurement also reflected higher DNA binding ability for 2 than 1. Both complexes 1 and 2 (docking scores of −7.43 and −6.95, respectively) were found to be more active inhibitors than the free ligand acid (docking score of −5.5159) against the target α-amylase protein. This in silico study has shown that the herein reported compounds follow the rules of drug-likeness and exhibit good potential for bioavailability.
Influence of the Abiotic Elicitors Ag Salts of Aspartic Acid Derivatives, Self-Organized in Nanofibers with Monomeric and Dimeric Molecular Structures, on the Antioxidant Activity and Stevioside Content in Micropropagated Stevia rebaudiana Bert.
Authors: Sichanova Mariana , Geneva Maria , Petrova Maria , Miladinova-Georgieva Kamelia , Kirova Elisaveta , Nedev Trendafil , Tsekova Daniela , Ivanova Viktoria , Trendafilova Antoaneta
Published: October 2023

The use of nanomaterials in biotechnology for the in vitro propagation of medical plants and the accumulation of certain biologically active metabolites is becoming an efficient strategy. This study aimed to evaluate the influence of the concentration (0, 1, 10, 50, and 100 mg L−1) of two types of nanofibers on the growth characteristics, the antioxidant status, and the production of steviol glycosides in micropropagated Stevia rebaudiana Bert. plantlets. The nanofibers were synthesized by aspartic acid derivatives (L-Asp) Ag salts self-organized into nanofibers with two different molecular structures: monomeric, containing one residue of L-Asp with one hydrophilic head which bonds one Ag ion (NF1-Ag salt); and dimeric, containing two residues of L-Asp with two hydrophilic heads which bond two Ag ions (NF2-Ag salt). An increase in the shoots from the explants’ number and length, biomass accumulation, and micropropagation rate was achieved in the plants treated with the NF1-Ag salt in concentrations from 1 to 50 mg L−1 after 30 days of in vitro proliferation compared to the NF2-Ag salt. In contrast, the plants grown on MS media supplemented with NF2-Ag salt exhibited an increase in the level of stevioside, rebaudioside A, and mono- (CQA) and dicaffeoylquinic (DCQA) acids as compared to the NF1-Ag salt.
A Novel Polymer Inclusion Membrane-Based Green Optical Sensor for Selective Determination of Iron: Design, Characterization, and Analytical Applications
Authors: Sánchez-Ponce Lorena , Casanueva-Marenco María José , Díaz-de-Alba Margarita , Galindo-Riaño María Dolores , Granado-Castro María Dolores
Published: October 2023

The design, characterization, and analytical application of a green optical sensor for the selective determination of Fe(II) ions is proposed. The sensor is based on the immobilization of the chromogenic reagent picolinaldehyde salicyloylhydrazone (SHPA) within a polymer inclusion membrane. To reduce solvent usage, the reagent was synthesized using a green mechanochemical procedure. The components for sensor preparation were optimized with a sequential simplex method and the optimal composition was found to be 0.59 g cellulose triacetate (base polymer), 0.04 g SHPA (chemosensor reagent), 4.9 mL dibutyl phthalate (plasticizer), and 38 mL dichloromethane (solvent). The conditions of iron analysis were also optimized resulting in pH 6 for aqueous solution, 90 min exposure time and 10 min short-term stability. The optical sensor showed a linear range from the limit of detection (0.48 µmol L−1) to 54 µmol L−1 Fe(II). The precision of the method was found to be 1.44% and 1.19% for 17.9 and 45 µmol L−1 Fe(II), respectively. The characteristics of the sensor allowed the design of a Fe(II)/Fe(III) speciation scheme. The methodology was successfully applied to the determination of iron in food preservatives, food additives, and dietary supplement. Additionally, the Fe speciation scheme was successfully applied to an agricultural fertilizer.