bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of Electromagnetic Stirring Roller Arrangement Pattern on Magnetic Field Simulation and Solidification Structure of PW800 Steel in the Second Cooling Zone
Authors: Xiao Zhixiang , Zhang Guifang , Liu Daiwei , Wu Chenhui
Published: February 2024

Strand electromagnetic stirring (S-EMS), a technique applied in the secondary cooling zone, enhances the solidification structure of casting slabs. This study examines how the arrangement pattern of electromagnetic stirring rollers—face-to-face, side-to-side or up-down misalignment produces this enhancement. It uses simulations to analyze the electromagnetic field distribution in these configurations. The findings demonstrate that: (1) The magnetic flux density distribution in the casting slab is related to the arrangement pattern of the electromagnetic stirring rollers. (2) The face-to-face arrangement produces the largest and most concentrated electromagnetic force compared to the other two arrangement patterns. (3) S-EMS can effectively improve the equiaxed grain ratio of casting slabs. Before and after EMS is turned on, casting slabs’ average equiaxed grain ratio goes up from 8% to 33%.
Effect of an Effervescent Multivitamin on Color and Surface Roughness of Micro-Hybrid Dental Resin Composites
Authors: Doğu Kaya Bengü , Yılmaz Atalı Pınar , Özmen Seda , Öztürk Selinsu , Tarçın Bilge
Published: February 2024

The use of multivitamins has become widespread globally, yet there is a scarcity of studies investigating their impact on resin composite restorations. This study aimed to evaluate the effect of an effervescent multivitamin tablet on micro-hybrid dental resin composites’ surface roughness and color. Fifty disc-shaped samples (8 × 2 mm, shade A2; n = 10) were prepared and polished using five different micro-hybrid resin composites (Pergamon, Dentac, Turkey; Estelite Posterior, Tokuyama, Japan; Geanial Anterior, GC, Japan; Charisma Opal, Kulzer, Germany; Beautifil II, Shofu, USA). Samples were immersed in 200 mL water to one effervescent multivitamin tablet (Redoxon Triple Action, Bayer) at 24 °C for 2 min a day in 24 h intervals for 30 days. All samples’ surface roughness (Ra) and ΔE(L*a*b) measurements were recorded at the beginning and end of the 30 days. The Wald chi-square and a two-way ANOVA were used for statistical analysis (significance level p < 0.05). The resin composite type and exposure to the multivitamin had a statistically significant effect on Ra values (p < 0.05). The resin composite type had a statistically significant effect on ΔE values, likely due to the higher mean value of BII (p = 0.040). The surface roughness and color of resin composites can be affected by multivitamins with a pH value of 3.0. Therefore, it is important to consider the patient’s routine vitamin intake during resin composite selection. Additional research is required to explore the properties of different dental restorative materials.
Crucial Role of Ni Point Defects and Sb Doping for Tailoring the Thermoelectric Properties of ZrNiSn Half-Heusler Alloy: An Ab Initio Study
Authors: Ascrizzi Eleonora , Ribaldone Chiara , Casassa Silvia
Published: February 2024

In the wide group of thermoelectric compounds, the half-Heusler ZrNiSn alloy is one of the most promising materials thanks to its thermal stability and narrow band gap, which open it to the possibility of mid-temperature applications. A large variety of defects and doping can be introduced in the ZrNiSn crystalline structure, thus allowing researchers to tune the electronic band structure and enhance the thermoelectric performance. Within this picture, theoretical studies of the electronic properties of perfect and defective ZrNiSn structures can help with the comprehension of the relation between the topology of defects and the thermoelectric features. In this work, a half-Heusler ZrNiSn alloy is studied using different defective models by means of an accurate Density Functional Theory supercell approach. In particular, we decided to model the most common defects related to Ni, which are certainly present in the experimental samples, i.e., interstitial and antisite Ni and a substitutional defect consisting of the replacement of Sn with Sb atoms using concentrations of 3% and 6%. First of all, a comprehensive characterization of the one-electron properties is performed in order to gain deeper insight into the relationship between structural, topological and electronic properties. Then, the effects of the modeled defects on the band structure are analyzed, with particular attention paid to the region between the valence and the conduction bands, where the defective models introduce in-gap states with respect to the perfect ZrNiSn crystal. Finally, the electronic transport properties of perfect and defective structures are computed using semi-classical approximation in the framework of the Boltzmann transport theory as implemented in the Crystal code. The dependence obtained of the Seebeck coefficient and the power factor on the temperature and the carrier concentration shows reasonable agreement with respect to the experimental counterpart, allowing possible rationalization of the effect of the modeled defects on the thermoelectric performance of the synthesized samples. As a general conclusion, defect-free ZrNiSn crystal appears to be the best candidate for thermoelectric applications when compared to interstitial and antisite Ni defective models, and substitutional defects of Sn with Sb atoms (using concentrations of 3% and 6%) do not appreciably improve electronic transport properties.
Zn-Based Alloys for Plain Bearings—Influence of Al and Cu Content on Mechanical Properties
Authors: Kiefel Angelika , Gimmler Steffen , Broeckmann Christoph , Vroomen Uwe
Published: February 2024

In recent decades, the requirements for plain bearing materials have continually increased, especially with new applications such as wind turbines, which require larger bearings. These new applications have completely different property profiles compared with, for example, bearings in automotive construction. Larger bearings need high strength and wear resistance, which established bearing materials cannot fulfill. Therefore, new alloy systems are required. This publication focuses on the influence of alloy composition and test temperature on the mechanical properties of ZnAlCu alloys. Centrifugally cast specimens were produced for the fabrication of test specimens, which were used to determine the mechanical and tribological properties. Fracture surface and wear trace analysis with scanning electron and light microscopy were used to determine occurring failure and wear mechanisms and to analyze the influence of microstructure on failure. Depending on the composition of the ZnAlCu alloys, up to three times higher strengths can be achieved compared with the white metal alloy SnSb12Cu6ZnAg. Furthermore, all the alloys investigated show good wear properties. Up to 11 wt.% aluminum and 1.5 wt.% copper, a significant decrease in the wear coefficient was observed. Knowledge about the correlation between microstructure, properties, and failure mechanisms of ZnAlCu alloys can be used to produce bearing metal alloys suitable for a wide range of applications. Since the strength values lie between those of white metals and bronze, new fields of application can also be accessed.
Characterization of Flexural Behavior of Hybrid Concrete-Filled Fiber-Reinforced Plastic Piles
Authors: Kim Sun-Hee
Published: February 2024

The reinforcing fibers in filament winding fiber-reinforced polymer (FFRP) are not arranged in the axial direction; thus, the members are vulnerable to bending and shear stresses. To address the limitations, this study evaluated FRP-concrete composite piles with reinforcing fiber arranged in circumferential directions. In particular, modular pultruded FRP (PFRP) members were fabricated with reinforcing fibers arranged in the axial and circumferential directions. The exterior of the fabricated PFRP members was reinforced with FFRP, and the flexural performance of these members was investigated through flexural strength tests. The results obtained from the flexural tests and flexural-stiffness prediction formula differed by approximately 0.72–1.36 times. A comparison between the results of the flexural test and flexural-strength prediction equation showed an error of approximately 1 to 10%.
Combined Soft Grasping and Crawling Locomotor Robot for Exterior Navigation of Tubular Structures
Authors: Mendoza Nicolás , Haghshenas-Jaryani Mahdi
Published: February 2024

This paper presents the design, development, and testing of a robot that combines soft-body grasping and crawling locomotion to navigate tubular objects. Inspired by the natural snakes’ climbing locomotion of tubular objects, the soft robot includes proximal and distal modules with radial expansion/contraction for grasping around the objects and a longitudinal contractile–expandable driving module in-between for providing a bi-directional crawling movement along the length of the object. The robot’s grasping modules are made of fabrics, and the crawling module is made of an extensible pneumatic soft actuator (ePSA). Conceptual designs and CAD models of the robot parts, textile-based inflatable structures, and pneumatic driving mechanisms were developed. The mechanical parts were fabricated using advanced and conventional manufacturing techniques. An Arduino-based electro-pneumatic control board was developed for generating cyclic patterns of grasping and locomotion. Different reinforcing patterns and materials characterize the locomotor actuators’ dynamical responses to the varying input pressures. The robot was tested in a laboratory setting to navigate a cable, and the collected data were used to modify the designs and control software and hardware. The capability of the soft robot for navigating cables in vertical, horizontal, and curved path scenarios was successfully demonstrated. Compared to the initial design, the forward speed is improved three-fold.
Model Selection Path and Construction of Model Confidence Set under High-Dimensional Variables
Authors: Wen Faguang , Jiang Jiming , Luan Yihui
Published: February 2024

Model selection uncertainty has drawn a lot of attention from academics recently because it significantly affects parameter estimation and prediction. Scholars are currently addressing and quantifying uncertainty in model selection by concentrating on model combining and model confidence sets. In this paper, we present a new approach for building model confidence sets, which we call AMac. We provide a theoretical lower bound on the degree of confidence in the model confidence sets that AMac has built. Furthermore, we discuss how the implementation of current model confidence set construction methods becomes difficult when dealing with high-dimensional variables. To address this problem, we suggest building model selection paths (MSP) as a solution. We develop an algorithm for building MSP and show its effectiveness by utilizing the theories of adaptive lasso and lars. We perform an extensive set of simulation experiments to compare the performances of Mac and AMac methods. According to the results, AMac is more stable when there are fluctuations in noise levels. The model confidence sets built by AMac, in particular, achieve coverage rates that are closer to the desired confidence level, especially in the presence of high noise levels. To further confirm that MSP can successfully generate model confidence sets that maintain the given confidence level as the sample size increases, we conduct extensive simulation tests with high-dimensional variables. Ultimately, we hope that the strategies and concepts discussed in this work will improve results in subsequent research on the uncertainty of model selection.
Combinatorial Estimations on Burnside Type Problems
Authors: Beletskiy Anton , Ivanov-Pogodaev Ilya
Published: February 2024

The Burnside problem, formulated by W. Burnside in 1902, is one of the most well-known and important open questions in the field of Group Theory. Despite significant progress made in the past century towards solving this problem, its complete solution remains unknown. In this paper, we investigate one of the approaches to solving the Burnside problem based on the application of an iterative theory of small cancellations and canonical forms developed by E. Rips in recent years. We present a novel self-contained exposition of this theory and utilize it to obtain new estimates on the infiniteness of initial approximations of Burnside groups where only a finite number of periodic relations is used for relatively small odd exponents (n>120).
Measurement Studies Utilizing Similarity Evaluation between 3D Surface Topography Measurements
Authors: Liu Lijie , Li Beiwen , Qin Hantang , Li Qing
Published: February 2024

In the realm of quality assurance, the significance of statistical measurement studies cannot be overstated, particularly when it comes to quantifying the diverse sources of variation in measurement processes. However, the complexity intensifies when addressing 3D topography data. This research introduces an intuitive similarity-based framework tailored for conducting measurement studies on 3D topography data, aiming to precisely quantify distinct sources of variation through the astute application of similarity evaluation techniques. In the proposed framework, we investigate the mean and variance of the similarity between 3D surface topography measurements to reveal the uniformity of the surface topography measurements and statistical reproducibility of the similarity evaluation procedure, respectively. The efficacy of our framework is vividly demonstrated through its application to measurements derived from additive-fabricated specimens. We considered four metal specimens with 20 segmented windows in total. The topography measurements were obtained by three operators using two scanning systems. We find that the repeatability variation of the topography measurements and the reproducibility variation in the measurements induced by operators are relatively smaller compared with the variation in the measurements induced by optical scanners. We also notice that the variation in the surface geometry of different surfaces is much larger in magnitude compared with the repeatability variation in the topography measurements. Our findings are consistent with the physical intuition and previous research. The ensuing experimental studies yield compelling evidence, affirming that our devised methods are adept at providing profound insights into the multifaceted sources of variation inherent in processes utilizing 3D surface topography data. This innovative framework not only showcases its applicability but also underlines its potential to significantly contribute to the field of quality assurance. By offering a systematic approach to measuring and comprehending variation in 3D topography data, it stands poised to become an indispensable tool in diverse quality assurance contexts.
Average Consensus Tracking of Weight-Balanced Multi-Agent Systems via Sampled Data
Authors: Huo Baoyu , Ma Jian , Du Mingjun , Yin Lijian
Published: February 2024

This paper studies the average consensus tracking problem of first-order multi-agent systems under directed topologies. A control protocol is constructed based on the neighbors’ agent sampled information. With the help of the matrix theory and frequency domain analysis, the necessary and sufficient condition can be induced for the average consensus tracking of multi-agent systems, although the weight-balanced condition is not satisfied. In addition, a numerical simulation example is given to illustrate the effectiveness of the proposed results.
Magnetic Filaments: Formation, Stability, and Feedback
Authors: Kuznetsov Evgeny A. , Mikhailov Evgeny A.
Published: February 2024

As is well known, magnetic fields in space are distributed very inhomogeneously. Sometimes, field distributions have forms of filaments with high magnetic field values. As many observations show, such a filamentation takes place in convective cells in the Sun and other astrophysical objects. This effect is associated with the frozenness of the magnetic field into a medium with high conductivity that leads to the compression of magnetic field lines and formation of magnetic filaments. We analytically show, based on the general analysis, that the magnetic field intensifies in the regions of downward flows in both two-dimensional and three-dimensional convective cells. These regions of the hyperbolic type in magnetic fields play the role of a specific attractor. This analysis was confirmed by numerical simulations of 2D roll-type convective cells. Without dissipation, the magnetic field grows exponentially in time and does not depend on the aspect ratio between the horizontal and vertical scales of the cell. An increase due to compression in the magnetic field of highly conductive plasma is saturated due to the natural limitation associated with dissipative effects when the maximum magnitude of a magnetic field is of the order of the root of the magnetic Reynolds number Rem. For the solar convective zone, the mean kinetic energy density exceeds the mean magnetic energy density for at least two orders of magnitude, which allows one to use the kinematic approximation of the MHD induction equation. In this paper, based on the stability analysis, we explain why downward flows influence magnetic filaments, making them flatter with orientation along the interfaces between convective cells.
Infective Endocarditis by Capnocytophaga Species—A Narrative Review
Authors: Spentzouri Despoina , Baliou Stella , Ioannou Petros
Published: February 2024

Bacteria belonging to the genus Capnocytophaga are thin, capnophilic, Gram-negative bacilli with tapered ends that include nine species that are isolated from the mouth of humans and animals and, from a phylogenetical perspective, they belong to the family Flavobacteriaceae. Two more species, namely C. endodontalis and C. stomatis have been recovered from a periapical abscess and human and animal infections, respectively. Capnocytophaga spp. can cause serious and potentially life-threatening infections in humans, such as bacteremia and meningitis, most commonly in the context of penetrating trauma as a result of contact with animals, especially after animal bites. Other invasive diseases such as osteomyelitis, septic arthritis, and infective endocarditis (IE) may also occur more rarely. The aim of this study was to review all previously described cases of IE by Capnocytophaga spp. and provide information about the epidemiology, microbiology, antimicrobial susceptibility, clinical characteristics, treatment, and outcomes of this infection. A narrative review based on a search in PubMed, the Cochrane Library, and Scopus was performed. Studies published until 11 September 2023 providing relevant data for IE caused by Capnocytophaga spp. in humans were included. A total of 31 studies containing data from 31 patients were included. A history of dog bites was present in 10 out of 26 patients (38.5%). A prosthetic valve was present in 3 patients (9.7%). The most commonly infected valve was the aortic valve, followed by the tricuspid valve. Fever, embolic phenomena, paravalvular abscess, and sepsis were the most common clinical presentations. Beta-lactams and aminoglycosides were the antimicrobials most commonly used. Surgery was performed in 20 patients (64.5%). Overall mortality reached 16.1%.
Current German Recommendations and International Research on the Use of COVID-19 Boosters among Health Care Providers in 2024: A Narrative Review
Authors: Pitak-Arnnop Poramate , Ngamskulrungroj Popchai , Mahanonda Nithi , Auychai Prim , Frech Benjamin , Shavlokhova Veronika , Stoll Christian
Published: February 2024

While the World Health Organization (WHO) has de-escalated coronavirus disease 2019 (COVID-19) from a global health emergency, ongoing discussions persist as new viral variants. This article aimed to consolidate German recommendations and international research to offer health care providers (HCPs) a comprehensive guide on COVID-19 boosters in 2024. The review outlines key recommendations from the German Robert Koch Institute. HCPs should receive COVID-19 boosters at least 12 months after their last vaccination or COVID-19 infection, contingent on the prevalent viral variant(s) in the region. However, excessive doses and/or frequent boosters, especially with mRNA vaccines, may lead to immune imprinting, T-cell exhaustion, and immunoglobulin (Ig) switching. Notably, this review highlights the significance of Ig, particularly IgA and IgG subclasses, in influencing infection risk and disease progression. Furthermore, it explores the implications of mRNA vaccine technology and potential adverse effects related to excessive dosing. In conclusion, this article provides a comprehensive analysis of COVID-19 vaccine boosters for HCPs, synthesising current recommendations, scientific debates, and considerations for optimising protection against SARS-CoV-2 in the evolving landscape of the post-pandemic era.
Effect of Drugs Used in Pharmacotherapy of Type 2 Diabetes on Bone Density and Risk of Bone Fractures
Authors: Wikarek Agnieszka , Grabarczyk Małgorzata , Klimek Katarzyna , Janoska-Gawrońska Agata , Suchodolska Magdalena , Holecki Michał
Published: February 2024

This review summarizes the complex relationship between medications used to treat type 2 diabetes and bone health. T2DM patients face an increased fracture risk despite higher bone mineral density; thus, we analyzed the impact of key drug classes, including Metformin, Sulphonylureas, SGLT-2 inhibitors, DPP-4 inhibitors, GLP-1 agonists, and Thiazolidinediones. Metformin, despite promising preclinical results, lacks a clear consensus on its role in reducing fracture risk. Sulphonylureas present conflicting data, with potential neutral effects on bone. SGLT-2 inhibitors seem to have a transient impact on serum calcium and phosphorus, but evidence on their fracture association is inconclusive. DPP-4 inhibitors emerge as promising contributors to bone health, and GLP-1 agonists exhibit positive effects on bone metabolism, reducing fracture risk. Thiazolidinediones, however, demonstrate adverse impacts on bone, inducing loss through mesenchymal stem cell effects. Insulin presents a complex relationship with bone health. While it has an anabolic effect on bone mineral density, its role in fracture risk remains inconsistent. In conclusion, a comprehensive understanding of diabetes medications’ impact on bone health is crucial. Further research is needed to formulate clear guidelines for managing bone health in diabetic patients, considering individual profiles, glycemic control, and potential medication-related effects on bone.
Creatine Acts as a Mediator of the Causal Effect of Obesity on Puberty Onset in Girls: Evidence from Mediation Mendelian Randomization Study
Authors: Jin Chuandi , Zhao Guoping
Published: February 2024

Epidemiological studies have linked obesity to the onset of puberty, while its causality and the potential metabolite mediators remain unclear. We employed a two-sample Mendelian randomization (MR) design to evaluate the causal effects of obesity on puberty onset and its associated diseases including type 2 diabetes (T2D) and cardiovascular diseases (CVDs). The potential mediators in this pathway were further explored using a two-step MR design. The robustness of our findings was evaluated using sensitivity analyses. Our MR results revealed that childhood obesity/BMI were causally associated with an increased Tanner stage in girls, younger age at menarche, and increased risk of adulthood T2D and CVD. However, neither childhood BMI nor obesity had a causal effect on the Tanner stage in boys. Mediation analysis further indicated that increased creatine served as a mediator for the causal pathway from childhood obesity/BMI to the Tanner stage of girls, while early puberty onset in girls played a mediating role in the pathway linking childhood obesity to increased risk of adulthood T2D and CVD. This study indicated that the risk of early puberty onset in girls and its associated health issues can be potentially reduced by preventing childhood obesity. The involvement of creatine in this process needs to be further validated and explored.
Comparative Metabolomics of Ligulate and Tubular Flowers of Two Cultivars of Calendula officinalis L.
Authors: Ossipov Vladimir , Khazieva Firdaus , Baleev Dmitry , Salminen Juha-Pekka , Sidelnikov Nikolay
Published: February 2024

Calendula officinalis L. is a well-known plant widely used in traditional medicine due to the presence of various biologically active compounds. The main raw material for the production of medicinal preparations is the inflorescence, which consists of ligulate and tubular flowers. However, the characteristics of the metabolome of these flowers are not fully understood. This study identified and compared the levels of major metabolites in the ligulate and tubular flowers of two C. officinalis cultivars, ‘Golden Sea’ (GS) and ‘Paradise Garden’ (PG). The metabolome was analysed using ultra-performance liquid chromatography with photodiode array detection and a Q Exactive Orbitrap high-resolution mass spectrometer. It was found that the tubular flowers of both PG and GS cultivars had higher levels of lipids, phenolamides and caffeoylquinic acids and lower levels of triterpenoid glycosides than the ligulate flowers. It was also shown that the inflorescences of the GS, which had a 35% higher proportion of tubular flowers, contained 30% more phenolic compounds and 50% more lipids than the PG. Thus, the results obtained extend our understanding of the features in the metabolomes of ligulate and tubular flowers and suggest that the quality of inflorescences of C. officinalis cultivars, as a source of medicinal preparations, is strongly influenced by the proportion of ligulate and tubular flowers.
Employing 11-Ketotestosterone as a Target Analyte for Adrenosterone (11OXO) Administration in Doping Controls
Authors: Piper Thomas , Fußhöller Gregor , Thevis Mario
Published: February 2024

Adrenosterone (Androst-4-ene-3,11,17-trione, 11OXO) is forbidden in sports according to the Prohibited List of the World Anti-Doping Agency. The administration of 11OXO may be detected by monitoring the urinary concentrations of its main human metabolites 11β-hydroxy-androsterone and 11β-hydroxy-etiocholanolone. Preliminary urinary concentration and concentration ratio thresholds have been established for sports drug testing purposes, but adaptations are desirable as the suggested limits would result in numerous suspicious findings due to naturally elevated concentrations and ratios. Recently, the metabolism of 11-oxo-testosterone (KT) was investigated in the context of anti-doping research, resulting in a preliminary urinary concentration threshold and a confirmation procedure based on the determination of carbon isotope ratios (CIRs). Gas chromatography coupled to isotope ratio mass spectrometry was employed to investigate the CIRs of selected steroids. As KT is also a metabolite of 11OXO, the developed protocols for KT have been tested to elucidate their potential to detect the administration of 11OXO after a single oral dose of 100 mg. In order to further improve the analytical approach, the threshold for urinary concentrations of KT was re-investigated by employing a reference population of n = 5232 routine doping control samples. Quantification of urinary steroids was conducted by employing gas chromatography coupled to triple quadrupole mass spectrometry. Derived from these, a subset of n = 106 samples showing elevated concentrations of KT was investigated regarding their CIRs. By means of this, potentially positive samples due to the illicit administration of 11OXO or KT could be excluded, and the calculation of reference population-derived thresholds for the concentrations and CIR of KT was possible. Based on the results, the urinary concentration threshold for KT is suggested to be established at 130 ng/mL.
Fabrication of Li4Ti5O12 (LTO) as Anode Material for Li-Ion Batteries
Authors: Julien Christian M. , Mauger Alain
Published: February 2024

The most popular anode material in commercial Li-ion batteries is still graphite. However, its low intercalation potential is close to that of lithium, which results in the dendritic growth of lithium at its surface, and the formation of a passivation film that limits the rate capability and may result in safety hazards. High-performance anodes are thus needed. In this context, lithium titanite oxide (LTO) has attracted attention as this anode material has important advantages. Due to its higher lithium intercalation potential (1.55 V vs. Li+/Li), the dendritic deposition of lithium is avoided, and the safety is increased. In addition, LTO is a zero-strain material, as the volume change upon lithiation-delithiation is negligible, which increases the cycle life of the battery. Finally, the diffusion coefficient of Li+ in LTO (2 × 10−8 cm2 s−1) is larger than in graphite, which, added to the fact that the dendritic effect is avoided, increases importantly the rate capability. The LTO anode has two drawbacks. The energy density of the cells equipped with LTO anode is lower compared with the same cells with graphite anode, because the capacity of LTO is limited to 175 mAh g−1, and because of the higher redox potential. The main drawback, however, is the low electrical conductivity (10−13 S cm−1) and ionic conductivity (10−13–10−9 cm2 s−1). Different strategies have been used to address this drawback: nano-structuration of LTO to reduce the path of Li+ ions and electrons inside LTO, ion doping, and incorporation of conductive nanomaterials. The synthesis of LTO with the appropriate structure and the optimized doping and the synthesis of composites incorporating conductive materials is thus the key to achieving high-rate capability. That is why a variety of synthesis recipes have been published on the LTO-based anodes. The progress in the synthesis of LTO-based anodes in recent years is such that LTO is now considered a substitute for graphite in lithium-ion batteries for many applications, including electric cars and energy storage to solve intermittence problems of wind mills and photovoltaic plants. In this review, we examine the different techniques performed to fabricate LTO nanostructures. Details of the synthesis recipes and their relation to electrochemical performance are reported, allowing the extraction of the most powerful synthesis processes in relation to the recent experimental results.
Co3O4 Nanostructured Sensor for Electrochemical Detection of H2O2 as a Stress Biomarker in Barley: Fe3O4 Nanoparticles-Mediated Enhancement of Salt Stress Tolerance
Authors: Gerbreders Vjaceslavs , Krasovska Marina , Sledevskis Eriks , Mihailova Irena , Mizers Valdis
Published: February 2024

This research investigates the enhancement of barley’s resistance to salt stress by integrating nanoparticles and employing a nanostructured Co3O4 sensor for the electrochemical detection of hydrogen peroxide (H2O2), a crucial indicator of oxidative stress. The novel sensor, featuring petal-shaped Co3O4 nanostructures, exhibits remarkable precision and sensitivity to H2O2 in buffer solution, showcasing notable efficacy in complex analytes like plant juice. The research establishes that the introduction of Fe3O4 nanoparticles significantly improves barley’s ability to withstand salt stress, leading to a reduction in detected H2O2 concentrations, alongside positive impacts on morphological parameters and photosynthesis rates. The developed sensor promises to provide real-time monitoring of barley stress responses, providing valuable information on increasing tolerance to crop stressors.
Continuum Robots and Magnetic Soft Robots: From Models to Interdisciplinary Challenges for Medical Applications
Authors: Wang Honghong , Mao Yi , Du Jingli
Published: February 2024

This article explores the challenges of continuum and magnetic soft robotics for medical applications, extending from model development to an interdisciplinary perspective. First, we established a unified model framework based on algebra and geometry. The research progress and challenges in principle models, data-driven, and hybrid modeling were then analyzed in depth. Simultaneously, a numerical analysis framework for the principle model was constructed. Furthermore, we expanded the model framework to encompass interdisciplinary research and conducted a comprehensive analysis, including an in-depth case study. Current challenges and the need to address meta-problems were identified through discussion. Overall, this review provides a novel perspective on understanding the challenges and complexities of continuum and magnetic soft robotics in medical applications, paving the way for interdisciplinary researchers to assimilate knowledge in this domain rapidly.
Wind-Wave Synergistic Triboelectric Nanogenerator: Performance Evaluation Test and Potential Applications in Offshore Areas
Authors: Pan Zhen , Wu Weijian , Zhou Jiangtao , Hu Yili , Li Jianping , Wang Yingting , Ma Jijie , Wen Jianming
Published: February 2024

Triboelectric nanogenerators (TENGs) can effectively collect low-frequency, disordered mechanical energy and are therefore widely studied in the field of ocean energy collection. Most of the rotary TENGs studied so far tend to have insufficient rotation, resulting in slow charge transfer rates in low-frequency ocean environments. For this reason, in this paper, we propose a wind-wave synergistic triboelectric nanogenerator (WWS-TENG). It is different from the traditional rotary TENGs based on free-standing mode in that its power generation unit has two types of rotors, and the two rotors rotate in opposite directions under the action of wind energy and wave energy, respectively. This type of exercise can more effectively collect energy. The WWS-TENG has demonstrated excellent performance in sea wind and wave energy harvesting. In the simulated ocean environment, the peak power can reach 13.5 mW under simulated wind-wave superposition excitation; the output of the WWS-TENG increased by 49% compared to single-wave power generation. The WWS-TENG proposal provides a novel means of developing marine renewable energy, and it also demonstrates broad application potential in the field of the self-powered marine Internet of Things (IoT).
Experimental Investigation on the Effects of Tool Geometry and Cutting Conditions on Machining Behavior during Edge Finishing of Granite Using Concave and Chamfered Profiling Tools
Authors: Mateur Wael , Songmene Victor , Kouam Jules
Published: February 2024

Granite edge finishing through grinding is a common process in the granite processing industry, crucial for achieving the final desired shape and edge quality of products. This study focuses on the granite industry, specifically delving into the significance of grinding and polishing for improving aesthetics and extending material longevity. The experimental design entails a comprehensive factorial experiment plan involving two workpiece materials (white and black granite samples) and two cutting tool edge shapes (chamfer and concave), each with two grit sizes: G150 and G600. The cutting conditions varied and consisted of variations in spindle speeds (1500, 2500, 3500 rpm), feed rates (500, 1000, 1500 mm/min), and lubrication modes (wet/dry). The results uncover intricate relationships among these parameters and part quality, underscoring the pivotal role of tool geometry in achieving superior surface finishes and in controlling the cutting forces. These findings contribute to a nuanced understanding of the dynamic interplay between tool characteristics, material properties, and machining conditions within the granite industry.
Enhancement of the Visible Light Photodetection of Inorganic Photodiodes via Additional Quantum Dots Layers
Authors: Kang Seong Jae , Jeong Jun Hyung , Ma Jin Hyun , Park Min Ho , Ha Hyoun Ji , Yun Jung Min , Kim Yu Bin , Kang Seong Jun
Published: February 2024

Visible light photodetectors are extensively researched with transparent metal oxide holes/electron layers for various applications. Among the metal oxide transporting layers, nickel oxide (NiO) and zinc oxide (ZnO) are commonly adopted due to their wide band gap and high transparency. The objective of this study was to improve the visible light detection of NiO/ZnO photodiodes by introducing an additional quantum dot (QD) layer between the NiO and ZnO layers. Utilizing the unique property of QDs, we could select different sizes of QDs and responsive light wavelength ranges. The resulting red QDs utilized device that could detect light starting at 635 nm to UV (Ultra-violet) light wavelength and exhibited a photoresponsivity and external quantum efficiency (EQE) of 14.99 mA/W and 2.92% under 635 nm wavelength light illumination, respectively. Additionally, the green QDs, which utilized a device that could detect light starting at 520 nm, demonstrated photoresponsivity values of 8.34 mA/W and an EQE of 1.99% under 520 nm wavelength light illumination, respectively. In addition, we used X-ray photoelectron spectroscopy (XPS) and ultraviolet photoelectron spectroscopy (UPS) to investigate the origin of the photocurrents and the enhancement of the device’s performance. This study suggests that incorporating QDs with metal oxide semiconductors is an effective approach for detecting visible light wavelengths in transparent optoelectronic devices.
Ethanol and Higher Alcohols’ Production in Fungal and Bacterial Laboratory Cultures and Significance for Forensic Samples
Authors: Boumba Vassiliki A. , Velivasi Glykeria , Kourkoumelis Nikolaos
Published: February 2024

Ethanol can be produced by many microorganisms that colonize a dead body. Ethanol’s concentration depends on the congener higher alcohols, 1-propanol, isobutanol, 2-methyl-1-butanol, 3-methyl-1-butanol, and 1-butanol, as previous research has shown. This correlation is expressed by mathematical models which estimate the concentration of microbial ethanol. The aim of this contribution was to study the ethanol and higher alcohols’ production in various laboratory bacterial and fungal cultures and the applicability of the bacterial and fungal models (which concern the bacteria E. coli, S. aureus, K. pneumoniae, and E. faecalis, and the fungus C. albicans) in these samples, as well as in blood samples from autopsy cases, with the overall objective of investigating the models’ applicability in routine casework. The bacteria and fungus were cultured in conventional culture media and in denatured human blood cultures under various conditions. The alcohols’ concentrations were determined using a head space–gas chromatography–flame ionization detector (HS-GC-FID). The previously reported bacterial and yeast models were applied in the cultured samples and in blood from 122 autopsy cases. Our results showed that 1-propanol was not produced by C. albicans and E. faecalis under certain conditions. Also, 1-butanol was not produced by C. albicans, E. faecalis, and K. pneumonia under certain conditions. Furthermore, the bacterial models were applicable in postmortem samples irrespective of the microbes that were possibly activated in the sample, while the EC models showed the best applicability among all the bacterial and yeast models. The best applicability of the bacterial models was observed in autopsy blood with 0.10 g/L < BAC < 1.0 g/L in cases of violent and undetermined causes of death and in cases with putrefaction. Finally, the yeast models were applicable in limited, possibly special, autopsy cases. In conclusion, it could be inferred that the source of ethanol in any given postmortem blood sample is likely microbial if either most bacterial models or at least one model from each distinct bacterial species is successfully applicable.
Genomic Insights into Moderately Thermophilic Methanotrophs of the Genus Methylocaldum
Authors: Delherbe Nathalie A. , Pearce David , But Sergey Y. , Murrell J. Colin , Khmelenina Valentina N. , Kalyuzhnaya Marina G.
Published: February 2024

Considering the increasing interest in understanding the biotic component of methane removal from our atmosphere, it becomes essential to study the physiological characteristics and genomic potential of methanotroph isolates, especially their traits allowing them to adapt to elevated growth temperatures. The genetic signatures of Methylocaldum species have been detected in many terrestrial and aquatic ecosystems. A small set of representatives of this genus has been isolated and maintained in culture. The genus is commonly described as moderately thermophilic, with the growth optimum reaching 50 °C for some strains. Here, we present a comparative analysis of genomes of three Methylocaldum strains—two terrestrial M. szegediense strains (O-12 and Norfolk) and one marine strain, Methylocaldum marinum (S8). The examination of the core genome inventory of this genus uncovers significant redundancy in primary metabolic pathways, including the machinery for methane oxidation (numerous copies of pmo genes) and methanol oxidation (duplications of mxaF, xoxF1-5 genes), three pathways for one-carbon (C1) assimilation, and two methods of carbon storage (glycogen and polyhydroxyalkanoates). We also investigate the genetics of melanin production pathways as a key feature of the genus.
The Impact of Early-Life Cecal Microbiota Transplantation on Social Stress and Injurious Behaviors in Egg-Laying Chickens
Authors: Fu Yuechi , Hu Jiaying , Zhang Huanmin , Erasmus Marisa A. , Johnson Timothy A. , Cheng Heng-Wei
Published: February 2024

Injurious behaviors (i.e., aggressive pecking, feather pecking, and cannibalism) in laying hens are a critical issue facing the egg industry due to increased social stress and related health and welfare issues as well as economic losses. In humans, stress-induced dysbiosis increases gut permeability, releasing various neuroactive factors, causing neuroinflammation and related neuropsychiatric disorders via the microbiota–gut–brain axis, and consequently increasing the frequency and intensity of aggression and violent behaviors. Restoration of the imbalanced gut microbial composition has become a novel treatment strategy for mental illnesses, such as depression, anxiety, bipolar disorder, schizophrenia, impulsivity, and compulsivity. A similar function of modulating gut microbial composition following stress challenge may be present in egg-laying chickens. The avian cecum, as a multi-purpose organ, has the greatest bacterial biodiversity (bacterial diversity, richness, and species composition) along the gastrointestinal tract, with vitally important functions in maintaining physiological and behavioral homeostasis, especially during the periods of stress. To identify the effects of the gut microbiome on injurious behaviors in egg-laying chickens, we have designed and tested the effects of transferring cecal contents from two divergently selected inbred chicken lines on social stress and stress-related injurious behaviors in recipient chicks of a commercial layer strain. This article reports the outcomes from a multi-year study on the modification of gut microbiota composition to reduce injurious behaviors in egg-laying chickens. An important discovery of this corpus of experiments is that injurious behaviors in chickens can be reduced or inhibited through modifying the gut microbiota composition and brain serotonergic activities via the gut–brain axis, without donor-recipient genetic effects.
Inversion for 3D Conductivity and Chargeability Models Using EM Data Acquired by the New Airborne TargetEM System in Ontario, Canada
Authors: Cox Leif , Zhdanov Michael , Prikhodko Alexander
Published: February 2024

This paper introduces an original approach to the joint inversion of airborne electromagnetic (EM) data for three-dimensional (3D) conductivity and chargeability models using hybrid finite difference (FD) and integral equation (IE) methods. The inversion produces a 3D model of physical parameters, which includes conductivity, chargeability, time constant, and relaxation coefficients. We present the underlying principles of this approach and an example of a high-resolution inversion of the data acquired by a new active time domain airborne EM system, TargetEM, in Ontario, Canada. The new TargetEM system collects high-quality multicomponent data with low noise, high power, and a small transmitter–receiver offset. This airborne system and the developed advanced inversion methodology represent a new effective method for mineral resource exploration.
Unraveling Meso-Substituent Steric Effects on the Mechanism of Hydrogen Evolution Reaction in NiII Porphyrin Hydrides Using DFT Method
Authors: Li Xiaodong , Feng Ailing , Zu Yanqing , Liu Peitao
Published: February 2024

Substituents at the meso-site of metalloporphyrins profoundly influence the hydrogen evolution reaction (HER) mechanism. This study employs density functional theory (DFT) to computationally analyze NiII-porphyrin and its hydrides derived from tetrakis(pentafluorophenyl)porphyrin molecules, presenting stereoisomers in ortho- or para-positions. The results reveal that the spatial resistance effect of meso-substituted groups at the ortho- and para-positions induces significant changes in Ni-N bond lengths, angles, and reaction dynamics. For ortho-position substituents forming complex I, a favorable 88.88 Å³ spherical space was created, facilitating proton coordination and the formation of H2 molecules; conversely, para-position substituents forming complex II impeded H2 formation until bimolecular complexes arose. Molecular dynamics (MD) analysis and comparison were conducted on the intermediation products of I-H2 and (II-H)2, focusing on the configuration and energy changes. In the I-H2 products, H2 molecules underwent separation after 150 fs and overcame the 2.2 eV energy barrier. Subsequently, significant alterations in the spatial structure were observed as complex I deformed. In the case of (II-H)2, it was influenced by the distinctive “sandwich” configuration; the spatial structure necessitated overcoming a 6.7 eV energy barrier for H2 detachment and a process observed after 2400 fs.