bluuebunny/crossref_metadata_2025 huggingface dataset:
Mental Health of Children and Adolescents before and during the COVID-19 Pandemic: How Did the Lockdown Modify Psychiatric Emergencies in Tuscany, Italy?
Authors: Tavano Simone , Caini Saverio , Sforzi Idanna , Silvestri Caterina , Voller Fabio , Pisano Tiziana
Published: June 2023

The COVID-19 pandemic has deeply impacted several aspects of the lives of children and adolescents. We analyzed the trends of psychiatric disorders in the emergency room. The analysis comprised the pre-pandemic (2018–2019) and the pandemic years (2020–2021). We conducted a retrospective observational epidemiological study that compared admissions during the two periods on a sample of 1311 patients aged between 4 and 18, focusing on new admissions vs. relapse, demographic variables, lockdown severity, presentation of psychiatric symptoms, diagnosis, severity, and outcome. Over the two-year pandemic period, we observed a 33% decrease in admissions to the emergency room for non-psychiatric disorders and a 200% increase in admissions for psychiatric emergencies. This increase is concentrated in periods with fewer restrictions and in the second year of the pandemic. We also observed a greater impact of psychiatric disorders on female patients, a greater severity of psychiatric disorders, a change in diagnoses associated with the presentation of symptoms, and an increase in hospitalizations. The children’s psychiatric emergency service faced an “emergency within the emergency”. In the future, it will be necessary to continue the follow-up of these patients, strengthen the field of study of gender psychiatry, and intensify our efforts towards prevention.
The Impact of Frailty on Postoperative Complications in Total En Bloc Spondylectomy for Spinal Tumors
Authors: Kawai Masafumi , Demura Satoru , Kato Satoshi , Yokogawa Noriaki , Shimizu Takaki , Kurokawa Yuki , Kobayashi Motoya , Yamada Yohei , Nagatani Satoshi , Uto Takaaki , Murakami Hideki
Published: June 2023

Total en bloc spondylectomy (TES) is an effective treatment for spinal tumors. However, its complication rate is high, and the corresponding risk factors remain unclear. This study aimed to clarify the risk factors for postoperative complications after TES, including the patient’s general condition, such as frailty and their levels of inflammatory biomarkers. We included 169 patients who underwent TES at our hospital from January 2011–December 2021. The complication group comprised patients who experienced postoperative complications that required additional intensive treatments. We analyzed the relationship between early complications and the following factors: age, sex, body mass index, type of tumor, location of tumor, American Society of Anesthesiologists score, physical status, frailty (categorized by the 5-factor Modified Frailty Index [mFI-5]), neutrophil-to-lymphocyte ratio, C-reactive protein/albumin ratio, preoperative chemotherapy, preoperative radiotherapy, surgical approach, and the number of resected vertebrae. Of the 169 patients, 86 (50.1%) were included in the complication group. Multivariate analysis showed that high mFI-5 scores (odds ratio [OR] = 2.99, p < 0.001) and an increased number of resected vertebrae (OR = 1.87, p = 0.018) were risk factors for postoperative complications. Frailty and the number of resected vertebrae were independent risk factors for postoperative complications after TES for spinal tumors.
Multi-Level 3D Surgery for Obstructive Sleep Apnea: Could It Be the Future?
Authors: Eplite Angelo , Vicini Claudio , Meccariello Giuseppe , Iannella Giannicola , Maniaci Antonino , Cannavicci Angelo , Moretti Francesco , Facchini Fabio , Mazzocco Tommaso , Cammaroto Giovanni
Published: June 2023

(1) Background: Obstructive sleep apnea (OSA) is the most common sleep-related breathing disorder and is characterized by recurrent episodes of complete or partial obstruction of the upper airway, leading to reduced or absent breathing during sleep. A nocturnal upper airway collapse is often multi-levelled. The aim of this communication is to describe a 3D multi-level surgery setting in OSA pathology, introducing new surgical approaches, such as 4K-3D endoscopic visualization for the tongue base approach with the aid of a coblator and exoscopic visualization in the palatal approach. (2) Methods: Seven patients affected by OSA underwent 3D Barbed Reposition Pharyngoplasty (BRP) surgery associated with transoral coblation tongue base reduction and nose surgery. (3) Results: No patients experienced intra-operative, post-operative or delayed complications. For OSA multi-level 3D surgery, it took less than 2 h: the median 3D system setting time was 12.5 ± 2.3 min; the overall procedure time was 59.3 ± 26 min. (4) Conclusions: The use of the 4K-3D endoscope and coblator for tongue base resectioning and of the 3D exoscope for lateral pharyngoplasty represents an excellent system in multi-level OSA related surgery that could reduce the time and the costs compared to those of robotic surgery.
The Development of Intuitive and Analytic Thinking in Autism: The Case of Cognitive Reflection
Authors: Morsanyi Kinga , Hamilton Jayne
Published: June 2023

The cognitive reflection test (CRT) is a short measure of a person’s ability to resist intuitive response tendencies, and to produce normatively correct responses that are assumed to be based on effortful, analytic thinking. A remarkable characteristic of the CRT is that although the questions are open-ended, for each item, the vast majority of people either produce a correct, analytic response or a typical incorrect (i.e., intuitive) response. This unique feature of the CRT makes it possible to investigate the question of whether autistic and neurotypical people share the same intuitions. We report a study that included adolescents and young adults. In both age groups, autistic and neurotypical participants were matched on age, gender, cognitive ability, and educational background. In line with previous findings, the results showed an age-related increase in analytic responding on the CRT, and a decrease in intuitive responding. Crucially, the proportion of both intuitive and analytic responses across autistic and neurotypical participants was identical in both age groups. The current results are in contrast with claims that autistic individuals have an increased tendency toward an analytic/rational type of processing, which is commonly attributed to an impairment within their intuitive reasoning mechanisms.
Modern Assessments of Intelligence Must Be Fair and Equitable
Authors: Holden LaTasha R. , Tanenbaum Gabriel J.
Published: June 2023

Historically, assessments of human intelligence have been virtually synonymous with practices that contributed to forms of inequality and injustice. As such, modern considerations for assessing human intelligence must focus on equity and fairness. First, we highlight the array of diversity, equity, and inclusion concerns in assessment practices and discuss strategies for addressing them. Next, we define a modern, non-g, emergent view of intelligence using the process overlap theory and argue for its use in improving equitable practices. We then review the empirical evidence, focusing on sub-measures of g to highlight the utility of non-g, emergent models in promoting equity and fairness. We conclude with suggestions for researchers and practitioners.
Fatigue Analysis of Inter-Array Power Cables between Two Floating Offshore Wind Turbines Including a Simplified Method to Estimate Stress Factors
Authors: Beier Dennis , Schnepf Anja , Van Steel Sean , Ye Naiquan , Ong Muk Chen
Published: June 2023

The use of floating offshore wind farms for electrical energy supply is expected to rise significantly over the coming years. Suspended inter-array power cables are a new design to connect floating offshore wind turbines (FOWTs) with shorter cable lengths than conventional setups. The present study investigates the fatigue life of a suspended power cable with attached buoys connecting two spar-type FOWTs. Typical environmental conditions for the North Sea are applied. The nonlinear bending behavior of the power cable is considered in the analysis. Fatigue assessment is performed using the numerical software OrcaFlex based on stress factors obtained from cross-section analysis. An effective method for obtaining the stress factors is proposed for early engineering design stages and compared with the finite element software UFLEX simulation results. The simplified method delivers similar results for axial tension loads and conservative results for bending loads compared with results obtained from the finite element software. Stress components resulting from curvature variation are identified as the main contributors to fatigue damage. The most critical locations along the power cable for fatigue life are close to the hang-off points.
Sequence Stratigraphy, Sedimentology, and Reservoir Characteristics of the Middle Cretaceous Mishrif Formation, South Iraq
Authors: Zhang Leifu , Zhang Wenqi , Li Yong , Song Benbiao , Liu Dawang , Deng Ya , Xu Jiacheng , Wang Yuning
Published: June 2023

The Cenomanian–Early Turonian Mishrif Formation is a great contributor to oil production in Iraq. Integrating petrographic, mineralogical, and wireline logging data from 52 wells, this study provides an improved understanding of the sequence stratigraphy, depositional evolution, and reservoir characteristics of the Mishrif Formation in the Mesopotamian Basin, south Iraq. Five types of facies associations are classified: lagoon, shoal, rudist bioherm, shallow marine, and deep marine. Such a classification allows convenient differentiation and interpretation of wireline logs. A sequence stratigraphic framework including five third-order sequences (Mhf 1 to Mhf 5) for the Mishrif Formation is established mainly using wireline logging data of close-distance wells, with the aid of cores and thin sections. Two end-member depositional evolution stages are recognized, from clinoform-like progradational shoal complexes in Mhf 1 within a shallow marine environment, to tidal channels in Mhf 2–3 within a lagoon environment. For Mhf 4–5, abrupt changes in facies associations from north to south indicate the development of an intra-shelf basin where organic-rich mudstones directly overlie the shallow marine grainstone shoals and lagoonal wackestones. Reservoir characteristics and compartmentalization are directly controlled by the sequence stratigraphic framework. Sequence boundaries are featured by wackestones and mudstones overprinted by cementation; they are regionally correlatable and work as regional barriers. Shoal complexes in Mhf 1 and tidal channels in Mhf 2–3 are the main reservoir units. Mudstones and wackestones are intra-reservoir baffles and become more frequently developed towards the south, reflecting the increasing water depth towards south. The characterization of the tidal channels, clinoform-like shoals, and intrashelf basinal deposits in the current study could benefit later development of the Mishrif Formation.
An Experimental Study on the Resistance of a High-Speed Air Cavity Craft
Authors: Song Lin , Yu Jianxing , Yu Yang , Wang Zhaoyu , Wu Shibo , Gao Ruilong
Published: June 2023

For the marine industry, resistance reduction can reduce energy consumption and achieve protection of the marine environment. The use of air lubrication to reduce the resistance of ships is one of the most important ways. With this technology, high-speed air cavity crafts show immense potential as they can be utilized in various marine activities, such as emergency rescue, supply, and maritime security. Through experiments, this study presents an in-depth analysis of the effects of bubble chamber pressure and initial stern inclination on the resistance of high-speed air cavity crafts at different speeds. The results show that air pressure has a significant impact on resistance. It was found that as the speed of the ship increased, the resistance reduction effect became more prominent under the same pressure conditions. Moreover, the resistance tended to stabilize when the pressure reached a certain value. In addition to the air pressure, the longitudinal inclination does have an effect on resistance reduction. To achieve better resistance reduction, the initial stern inclination angle should be chosen appropriately. Furthermore, adjusting the angle with speed changes can optimize the resistance reduction effect. This experimental study provides critical support for conducting further research on high-speed air cavity crafts. The findings offer valuable insights into improving hull forms, guiding host selection, and assessing performance.
Aflatoxigenic Aspergillus Modulates Aflatoxin-B1 Levels through an Antioxidative Mechanism
Authors: Katati Bwalya , Kovacs Stan , Njapau Henry , Kachapulula Paul W. , Zwaan Bas J. , van Diepeningen Anne D. , Schoustra Sijmen E.
Published: June 2023

Aflatoxins (AFs) are considered to play important functions in species of Aspergillus section Flavi including an antioxidative role, as a deterrent against fungivorous insects, and in antibiosis. Atoxigenic Flavi are known to degrade AF-B1 (B1). To better understand the purpose of AF degradation, we investigated the degradation of B1 and AF-G1 (G1) in an antioxidative role in Flavi. Atoxigenic and toxigenic Flavi were treated with artificial B1 and G1 with or without the antioxidant selenium (Se), which is expected to affect levels of AF. After incubations, AF levels were measured by HPLC. To estimate which population would likely be favoured between toxigenic and atoxigenic Flavi under Se, we investigated the fitness, by spore count, of the Flavi as a result of exposure to 0, 0.40, and 0.86 µg/g Se in 3%-sucrose cornmeal agar (3gCMA). Results showed that levels B1 in medium without Se were reduced in all isolates, while G1 did not significantly change. When the medium was treated with Se, toxigenic Flavi significantly digested less B1, while levels of G1 significantly increased. Se did not affect the digestion of B1 in atoxigenic Flavi, and also did not alter levels of G1. Furthermore, atoxigenic strains were significantly fitter than toxigenic strains at Se 0.86 µg/g 3gCMA. Findings show that while atoxigenic Flavi degraded B1, toxigenic Flavi modulated its levels through an antioxidative mechanism to levels less than they produced. Furthermore, B1 was preferred in the antioxidative role compared to G1 in the toxigenic isolates. The higher fitness of atoxigenic over toxigenic counterparts at a plant non-lethal dose of 0.86 µg/g would be a useful attribute for integration in the broader biocontrol prospects of toxigenic Flavi.
Quota and Space Allocations of New Urban Land Supported by Urban Growth Simulations: A Case Study of Guangzhou City, China
Authors: Li Xiang , Zhu Jiang , Liu Tao , Yin Xiangdong , Yao Jiangchun , Jiang Hao , Bu Bing , Yan Jianlong , Li Yixuan , Chen Zhangcheng
Published: June 2023

Previous allocations of new urban land were ineffective because they lacked synergy between quota and space, challenging the government planning authority. This study proposes a new and more reasonable urban land allocation method to guide the smart growth of cities. We used a logistic regression model and multisource data to explore the laws of urban growth and employed a cellular automata (CA) model to simulate this under inertial and constrained scenarios. In addition, the disparities between both scenarios concerning allocation were analyzed. We realized the synergy of quota and space allocations of new urban land through urban growth simulation. Further, the allocation of new urban land was more consistent with the development strategy of Guangzhou under a constrained scenario. The allocation of space was more regular and concentrated under a constrained scenario, which aligns with the requirements of the Government Land Space Planning. Additionally, in the constrained scenario, the bottom lines of cultivated land protection, ecological service, and geological safety were better controlled. This study compensated for the shortcomings of the disjoined quota and space allocations of new urban land and proved that a constrained scenario can more effectively promote reasonable urban growth.
Influence of the Built Environment on Older Adults’ Travel Time: Evidence from the Nanjing Metropolitan Area, China
Authors: Sun Jingrui , Zhu Zhenjun , Han Ji , He Zhanpeng , Xu Xinfang
Published: June 2023

The built environment is among the critical factors in older adults’ travel behavior, and a favorable built environment can encourage them to travel and engage in various activities. Existing studies have mostly focused on exploring the correlation between the built environment and travel behavior, ignoring the heterogeneity between the two at different times of the day. In this study, we conducted structured, face-to-face interviews in the Nanjing (China) metropolitan area to investigate the time consumed per trip by older adults using various travel modes and used the structural equation and random forest models to explore the relationship between the built environment and older adults’ travel time. The results demonstrated that older adults had different perspectives on travel during different time periods. Different environments and the convenience of destinations affected their overall satisfaction during travel. We found a nonlinear relationship between the built environment and travel time. Metropolitan street connectivity initially had a positive effect on travel time until a certain threshold or peak, whereafter a gradual decline ensued. This nonlinear relationship also existed between the proportion of green space and the distance to subway stations. These results can guide the retrofitting and construction of age-friendly metropolitan infrastructure facilities that promote older adults’ mobility.
Bee-Friendly Native Seed Mixtures for the Greening of Solar Parks
Authors: Meyer Maren Helen , Dullau Sandra , Scholz Pascal , Meyer Markus Andreas , Tischew Sabine
Published: June 2023

Photovoltaics is one of the key technologies for reducing greenhouse gas emissions and achieving climate neutrality for Europe by 2050, which has led to the promotion of solar parks. These parks can span up to several hundred hectares, and grassland vegetation is usually created between and under the panels. Establishing species-rich grasslands using native seed mixtures can enhance a variety of ecosystem services, including pollination. We present an overall concept for designing native seed mixtures to promote pollinators, especially wild bees, in solar parks. It takes into account the specific site conditions, the small-scale modified conditions caused by the solar panels, and the requirement to avoid panel shading. We highlight the challenges and constraints resulting from the availability of species on the seed market. Furthermore, we provide an easy-to-use index for determining the value of native seed mixtures for wild bee enhancement and apply it as an example to several mixtures specifically designed for solar parks. The increased availability of regional seed would allow a more thorough consideration of pollinator-relevant traits when composing native seed mixtures, thereby enhancing ecosystem services associated with pollinators such as wild bees.
Tire Wear Sensitivity Analysis and Modeling Based on a Statistical Multidisciplinary Approach for High-Performance Vehicles
Authors: Napolitano Dell’Annunziata Guido , Adiletta Giovanni , Farroni Flavio , Sakhnevych Aleksandr , Timpone Francesco
Published: June 2023

One of the main challenges in maximizing vehicle performance is to predict and optimize tire behavior in different working conditions, such as temperature, friction, and wear. Starting from several approaches to develop tire grip and wear models, based on physical principles, experimental data, or statistical methods available in the literature, this work aims to propose a novel tire wear model that combines physical and statistical analysis on a large number of high-performance vehicle telemetries, tracks, and road data, as well as tires’ viscoelastic properties. Another contribution of this multidisciplinary study is the definition of the functional relationships that govern the tire–road interaction in terms of friction and degradation, conducting a thorough analysis of the car’s telemetry, the track and asphalt features, and the viscoelastic properties of the tires.
Effects of In-Situ Reaction, Extrusion Ratio and CeO2 on the Performance of Al-Ti-C-(Ce) Grain Refiners for Refining Pure Aluminum Grains
Authors: Bi Qianwen , Luo Xiaoxu , Guo Lu , Zuo Xiaoqing , Huang Bei , Yi Jianhong , Zhou Yun
Published: June 2023

Al-Ti-C-(Ce) grain refiners were prepared by combining in-situ reaction, hot extrusion, and adding CeO2. The effects of second phase TiC particle size and distribution, extrusion ratio, and Ce addition on the grain-refining performance of grain refiners were investigated. The results show that about 10 nm TiC particles are dispersed on the surface and inside of 100–200 nm Ti particles by in-situ reaction. The Al-Ti-C grain refiners, which are made, by hot extrusion, of a mixture of in-situ reaction Ti/TiC composite powder and Al powder, increase the effective nucleation phase of α-Al and hinder grain growth due to the fine and dispersed TiC; this results in the average size of pure aluminum grains to decrease from 1912.4 μm to 504.8 μm (adding 1 wt.% Al-Ti-C grain refiner). Additionally, with the increase of the extrusion ratio from 13 to 30, the average size of pure aluminum grains decreases further to 470.8 μm. This is because the micropores in the matrix of grain refiners are reduced, and the nano-TiC aggregates are dispersed with the fragmentation of Ti particles, resulting in a sufficient Al-Ti reaction and an enhanced nucleation effect of nano-TiC. Furthermore, Al-Ti-C-Ce grain refiners were prepared by adding CeO2. Under the conditions of holding for 3–5 min and adding a 5.5 wt.% Al-Ti-C-Ce grain refiner, the average size of pure aluminum grains is reduced to 48.4–48.8 μm. The reason for the excellent grain-refining and good anti-fading performance of the Al-Ti-C-Ce grain refiner is presumedly related to the Ti2Al20Ce rare earth phases and [Ce] atoms, which hinder agglomeration, precipitation, and dissolution of the TiC and TiAl3 particles.
Bioengineering Composite Aerogel-Based Scaffolds That Influence Porous Microstructure, Mechanical Properties and In Vivo Regeneration for Bone Tissue Application
Authors: Souto-Lopes Mariana , Fernandes Maria Helena , Monteiro Fernando Jorge , Salgado Christiane Laranjo
Published: June 2023

Tissue regeneration of large bone defects is still a clinical challenge. Bone tissue engineering employs biomimetic strategies to produce graft composite scaffolds that resemble the bone extracellular matrix to guide and promote osteogenic differentiation of the host precursor cells. Aerogel-based bone scaffold preparation methods have been increasingly improved to overcome the difficulties in balancing the need for an open highly porous and hierarchically organized microstructure with compression resistance to withstand bone physiological loads, especially in wet conditions. Moreover, these improved aerogel scaffolds have been implanted in vivo in critical bone defects, in order to test their bone regeneration potential. This review addresses recently published studies on aerogel composite (organic/inorganic)-based scaffolds, having in mind the various cutting-edge technologies and raw biomaterials used, as well as the improvements that are still a challenge in terms of their relevant properties. Finally, the lack of 3D in vitro models of bone tissue for regeneration studies is emphasized, as well as the need for further developments to overcome and minimize the requirement for studies using in vivo animal models.
Fabrication and Process Optimization of Chinese Fir-Derived SiC Ceramic with High-Performance Friction Properties
Authors: Liu Fuling , Chang Shanshan , Bai Yuanjuan , Li Xianjun , Zhou Xiaojian , Hu Jinbo
Published: June 2023

In this study, a novel friction material with biomass-ceramic (SiC) dual matrixes was fabricated using Chinese fir pyrocarbon via the liquid-phase silicon infiltration and in situ growth method. SiC can be grown in situ on the surface of a carbonized wood cell wall by mixing and calcination of wood and Si powder. The samples were characterized using XRD, SEM, and SEM–EDS analysis. Meanwhile, their friction coefficients and wear rates were tested to study their frictional properties. To explore the influence of crucial factors on friction performance, response surface analysis was also conducted to optimize the preparation process. The results showed that longitudinally crossed and disordered SiC nanowhiskers were grown on the carbonized wood cell wall, which could enhance the strength of SiC. The designed biomass-ceramic material had satisfying friction coefficients and low wear rates. The response surface analysis results indicate that the optimal process could be determined (carbon to silicon ratio of 3:7, reaction temperature of 1600 °C, and 5% adhesive dosage). Biomass-ceramic materials utilizing Chinese fir pyrocarbon could display great promise to potentially replace the current iron–copper-based alloy materials used in brake systems.
Effect of Zr2Al4C5 Content on the Mechanical Properties and Oxidation Behavior of ZrB2-SiC-Zr2Al4C5 Ceramics
Authors: Guo Qilong , Hua Liang , Ying Hao , Liu Ronghao , Lin Mei , Li Leilei , Wang Jing
Published: June 2023

ZrB2-SiC-Zr2Al4C5 multi-phase ceramics with uniform structure and high density were successfully prepared through the introduction of in situ synthesized Zr2Al4C5 into ZrB2-SiC ceramic via SPS at 1800 °C. A systematic analysis and discussion of the experimental results and proposed mechanisms were carried out to demonstrate the composition-dependent sintering properties, mechanical properties and oxidation behavior. The results showed that the in situ synthesized Zr2Al4C5 could be evenly distributed in the ZrB2-SiC ceramic matrix and inhibited the growth of ZrB2 grains, which played a positive role in the sintering densification of the composite ceramics. With increasing Zr2Al4C5 content, the Vickers hardness and Young’s modulus of composite ceramics gradually decreased. The fracture toughness showed a trend that first increased and then decreased, and was increased by about 30% compared with ZrB2-SiC ceramics. The major phases resulting from the oxidation of samples were ZrO2, ZrSiO4, aluminosilicate and SiO2 glass. With increasing Zr2Al4C5 content, the oxidative weight showed a trend that first increased then decreased; the composite ceramic with 30 vol.% Zr2Al4C5 showed the smallest oxidative weight gain. We believe that the presence of Zr2Al4C5 results in the formation of Al2O3 during the oxidation process, subsequently resulting in a lowering of the viscosity of the glassy silica scale, which in turn intensifies the oxidation of the composite ceramics. This would also increase oxygen permeation through the scale, adversely affecting the oxidation resistance of the composites with high Zr2Al4C5 content.
Cu2O/SnO2 Heterostructures: Role of the Synthesis Procedure on PEC CO2 Conversion
Authors: Zoli Maddalena , Guzmán Hilmar , Sacco Adriano , Russo Nunzio , Hernández Simelys
Published: June 2023

Addressing the urgent need to mitigate increasing levels of CO2 in the atmosphere and combat global warming, the development of earth-abundant catalysts for selective photo-electrochemical CO2 conversion is a central and pressing challenge. Toward this purpose, two synthetic strategies for obtaining a Cu2O–SnO2 catalyst, namely co-precipitation and core–shell methods, were compared. The morphology and band gap energy of the synthesized materials were strongly different. The photoactivity of the core–shell catalyst was improved by 30% compared to the co-precipitation one, while its selectivity was shifted towards C1 products such as CO and formate. The stability of both catalysts was revealed by an easy and fast EIS analysis, indicating how the effective presence of a SnO2 shell could prevent the modification of the crystalline phase of the catalyst during PEC tests. Finally, directing the selectivity depending on the synthesis method used to produce the final Cu2O–SnO2 catalyst could possibly be implemented in syngas and formate transformation processes, such as hydroformylation or the Fischer–Tropsch process.
Physical, Mechanical, and Biological Properties of PMMA-Based Composite Bone Cement Containing Silver-Doped Bioactive and Antibacterial Glass Particles with Different Particles Sizes
Authors: Miola Marta , Lucchetta Giovanni , Verné Enrica
Published: June 2023

In the present work, antibacterial composite bone cement was designed by introducing a bioactive and antibacterial glass into a commercial formulation. The effect of glass particles’ addition on the curing parameters of the polymeric matrix was evaluated; moreover, the influence of the glass particle size on the glass dispersion, compressive and bending strength, bioactivity, and antibacterial effect was estimated. The results evidence a delay in the polymerization kinetics of the composite cement, which nevertheless complies with the requirements of the ISO standard. Morphological characterization provides evidence of good dispersion of the glass in the polymeric matrix and its exposition on the cement surface. The different glass grain sizes do not affect the composites’ bioactivity and compressive strength, while a slight reduction in bending strength was observed for samples containing glass powders with greater dimensions. The size of the glass particles also appears to have an effect on the antibacterial properties, since the composites containing larger glass particles do not produce an inhibition halo towards the S. aureus strain. The obtained results demonstrate that, by carefully tailoring the glass amount and size, a multifunctional device for artificial joint fixing, temporary prostheses, or spinal surgery can be obtained.
Analysis of Pore Structure in Cement Pastes with Micronized Natural Zeolite
Authors: Toma Ionut-Ovidiu , Stoian George , Rusu Mihai-Marius , Ardelean Ioan , Cimpoeşu Nicanor , Alexa-Stratulat Sergiu-Mihai
Published: June 2023

The continuous development of urban areas around the world led to an increase in construction material use and demand, with concrete seeing significant market uptake. Although significant progress has been made to reduce the environmental impact of concrete, there is still a stringent need for improvement. One of the most widely used methods to reduce the environmental impact of the cement industry and the construction industry alike is the replacement of ordinary Portland cement (OPC) by supplementary cementitious materials (SCM). Aside from by-products of industry, SCMs could also come from natural sources. Taking into account the porous structure of zeolites and their contribution to the improvement of the mechanical and durability properties of cement-based materials, the analysis of pore structure in cement pastes incorporating micronized natural zeolite is deemed necessary. In this research, the OPC was replaced by zeolite in three different percentages: 10%, 20%, and 30% by mass. The evolution of pore structure was investigated by means of nuclear magnetic resonance relaxometry at the curing ages of 1, 7, and 28 days. The microstructure of cement pastes was assessed by scanning electron microscopy investigations at 1, 7, 14, 21, and 28 days. The obtained results show that smaller pore sizes are present in cement pastes containing zeolites during the first 7 days. However, at the age of 28 days, the reference mix exhibits a similar pore structure to the mix containing 10% micronized zeolite due to the presence of larger amounts of hydration products. Increasing the replacement percentage to 30% results in larger pores, as indicated by larger values of the relaxation time.
Synthesis of Mesoporous and Hollow SiO2@ Eu(TTA)3phen with Enhanced Fluorescence Properties
Authors: Wang Zhiheng , Hu Xiaoli , Yang Yinqi , Wang Wei , Wang Yao , Gong Xuezhong , Geng Caiyun , Tang Jianguo
Published: June 2023

Lanthanide ions are extensively utilized in optoelectronic materials, owing to their narrow emission bandwidth, prolonged lifetime, and elevated fluorescence quantum yield. Inorganic non-metallic materials commonly serve as host matrices for lanthanide complexes, posing noteworthy challenges regarding loading quantity and fluorescence performance stability post-loading. In this investigation, an enhanced Stöber method was employed to synthesize mesoporous hollow silica, and diverse forms of SiO2@Eu(TTA)3phen (S@Eu) were successfully prepared. Transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), Fourier-transform infrared (FTIR) spectroscopy, and X-ray photoelectron spectroscopy (XPS) outcomes revealed the effective binding of silica with Eu(TTA)3phen through both physical adsorption and chemical bonding. This includes the formation of Si-O-C bonds between silica and the ligand, as well as Si-O-Eu bonds between silica and europium ions. Fluorescence tests demonstrated that the mesoporous SiO2@Eu(TTA)3phen(MS@Eu) composite exhibited the highest fluorescence intensity among the three structured silica composites, with a notable enhancement of 46.60% compared to the normal SiO2@Eu(TTA)3phen composite. The Brunauer–Emmett–Teller (BET) analysis indicated that the specific surface area plays a crucial role in influencing the fluorescence intensity of SiO2@Eu(TTA)3phen, whereby the prepared mesoporous hollow silica further elevated the fluorescence intensity by 61.49%. Moreover, SiO2@Eu(TTA)3phen demonstrated 11.11% greater cyclic stability, heightened thermal stability, and enhanced alkaline resistance relative to SiO2@Eu(TTA)3phen.
Scintillation Properties of Ba3RE(PO4)3 Single Crystals (RE = Y, La, Lu)
Authors: Takebuchi Yuma , Koshimizu Masanori , Ichiba Kensei , Kato Takumi , Nakauchi Daisuke , Kawaguchi Noriaki , Yanagida Takayuki
Published: June 2023

Eulytite-type Ba3RE(PO4)3 (RE = Y, La, and Lu) single crystals were synthesized by the floating zone method, and their scintillation properties were investigated. The powder X-ray diffraction measurement revealed that the single phase of Ba3RE(PO4)3 samples were successfully synthesized. The samples exhibited a luminescence peak due to self-trapped exciton at around 400 nm under vacuum ultraviolet and X-ray irradiation. The X-ray-induced scintillation decay time constants of the samples were several microseconds at room temperature. In the 241Am α-ray irradiated pulse height spectra, all the samples showed a clear full energy peak, and the absolute light yields of the Ba3Y(PO4)3, Ba3La(PO4)3, and Ba3Lu(PO4)3 single crystals were estimated to be 960, 1160, and 1220 ph/5.5 MeV-α, with a typical error of ±10%, respectively. The scintillation light yields of the Ba3RE(PO4)3 have been quantitatively clarified for the first time.
Developing an Interferogram-Based Module with Machine Learning for Maintaining Leveling of Glass Substrates
Authors: Chang Syuan-Cheng , Chang Chung-Ping , Wang Yung-Cheng , Chu Chi-Chieh
Published: June 2023

In this research, we propose a method that utilizes machine learning to maintain the parallelism of the resonant cavity in a Fabry–Perot interferometer designed specifically for glass substrates. Based on the optical principle and theory, we establish a proportional relationship between interference fringes and the inclination angle of the mirrors. This enables an accurate determination of the inclination angle using supervised learning, specifically classification. By training a machine learning model with labeled data, interference fringe patterns are categorized into three levels, with approximately 100 training data available for each level in each location. The experimental results of Level 2 and Level 3 classification indicate an average number of corrections of 2.55 and 3.55 times, respectively, in achieving the target position with a correction error of less than 30 arc seconds. These findings demonstrate the essential nature of this parallelism maintenance technology for the semiconductor industry and precision mechanical engineering.
Applications of the Tarig Transform and Hyers–Ulam Stability to Linear Differential Equations
Authors: Chitra L. , Alagesan K. , Govindan Vediyappan , Saleem Salman , Al-Zubaidi A. , Vimala C.
Published: June 2023

In this manuscript, we discuss the Tarig transform for homogeneous and non-homogeneous linear differential equations. Using this Tarig integral transform, we resolve higher-order linear differential equations, and we produce the conditions required for Hyers–Ulam stability. This is the first attempt to use the Tarig transform to show that linear and nonlinear differential equations are stable. This study also demonstrates that the Tarig transform method is more effective for analyzing the stability issue for differential equations with constant coefficients. A discussion of applications follows, to illustrate our approach. This research also presents a novel approach to studying the stability of differential equations. Furthermore, this study demonstrates that Tarig transform analysis is more practical for examining stability issues in linear differential equations with constant coefficients. In addition, we examine some applications of linear, nonlinear, and fractional differential equations, by using the Tarig integral transform.
A Reconstruction Approach for Concurrent Multiscale Topology Optimization Based on Direct FE2 Method
Authors: Zhao Ang , Tan Vincent Beng Chye , Li Pei , Liu Kui , Hu Zhendong
Published: June 2023

The rapid development of material science is increasing the demand for the multiscale design of materials. The concurrent multiscale topology optimization based on the Direct FE2 method can greatly improve computational efficiency, but it may lead to the checkerboard problem. In order to solve the checkerboard problem and reconstruct the results of the Direct FE2 model, this paper proposes a filtering-based reconstruction method. This solution is of great significance for the practical application of multiscale topology optimization, as it not only solves the checkerboard problem but also provides the optimized full model based on interpolation. The filtering method effectively eliminates the checkerboard pattern in the results by smoothing the element densities. The reconstruction method restores the smoothness of the optimized structure by interpolating between the filtered densities. This method is highly effective in solving the checkerboard problem, as demonstrated in our numerical examples. The results show that the proposed algorithm produces feasible and stable results.
Oscillation Criteria for Qusilinear Even-Order Differential Equations
Authors: Kachout Mnaouer , Cesarano Clemente , Abdel Menaem Amir , Hassan Taher S. , Glalah Belal A.
Published: June 2023

In this study, we extended and improved the oscillation criteria previously established for second-order differential equations to even-order differential equations. Some examples are given to demonstrate the significance of the results accomplished.
A New Visualization and Analysis Method for a Convolved Representation of Mass Computational Experiments with Biological Models
Authors: Klimenko Alexandra I. , Vorobeva Diana A. , Lashin Sergey A.
Published: June 2023

Modern computational biology makes widespread use of mathematical models of biological systems, in particular systems of ordinary differential equations, as well as models of dynamic systems described in other formalisms, such as agent-based models. Parameters are numerical values of quantities reflecting certain properties of a modeled system and affecting model solutions. At the same time, depending on parameter values, different dynamic regimes—stationary or oscillatory, established as a result of transient modes of various types—can be observed in the modeled system. Predicting changes in the solution dynamics type depending on changes in model parameters is an important scientific task. Nevertheless, this problem does not have an analytical solution for all formalisms in a general case. The routinely used method of performing a series of computational experiments, i.e., solving a series of direct problems with various sets of parameters followed by expert analysis of solution plots is labor-intensive with a large number of parameters and a decreasing step of the parametric grid. In this regard, the development of methods allowing the obtainment and analysis of information on a set of computational experiments in an aggregate form is relevant. This work is devoted to developing a method for the visualization and classification of various dynamic regimes of a model using a composition of the dynamic time warping (DTW-algorithm) and principal coordinates analysis (PCoA) methods. This method enables qualitative visualization of the results of the set of solutions of a mathematical model and the performance of the correspondence between the values of the model parameters and the type of dynamic regimes of its solutions. This method has been tested on the Lotka–Volterra model and artificial sets of various dynamics.
Some Further Coefficient Bounds on a New Subclass of Analytic Functions
Authors: Sun Yue-Juan , Arif Muhammad , Shi Lei , Faisal Muhammad Imran
Published: June 2023

The coefficient problem is an essential topic in the theory of univalent functions theory. In the present paper, we consider a new subclass SQ of analytic functions with f′(z) subordinated to 1/(1−z)2 in the open unit disk. This class was introduced and studied by Răducanu. Our main aim is to give the sharp upper bounds of the second Hankel determinant H2,3f and the third Hankel determinant H3,1f for f∈SQ. This may help to understand more properties of functions in this class and inspire further investigations on higher Hankel determinants for this or other popular sub-classes of univalent functions.
Adaptive Super-Twisting Sliding Mode Control of Active Power Filter Using Interval Type-2-Fuzzy Neural Networks
Authors: Wang Jiacheng , Fang Yunmei , Fei Juntao
Published: June 2023

Aiming at the unknown uncertainty of an active power filter system in practical operation, combining the advantages of self-feedback structure, interval type-2 fuzzy neural network, and super-twisting sliding mode, an adaptive super-twisting sliding mode control method of interval type-2 fuzzy neural network with self-feedback recursive structure (IT2FNN-SFR STSMC) is proposed in this paper. IT2FNN has an uncertain membership function, which can enhance the nonlinear ability and robustness of the network. The historical information will be stored and utilized by the self-feedback recursive structure (SFR) at runtime. Therefore, the novel IT2FNN-SFR is designed to improve the dynamic approximation effect of the neural network and reduce the dependence of the controller on the actual mathematical model. The adaptive rate of each weight of the neural network is designed by the Lyapunov method and gradient descent (GD) algorithm to ensure the convergence and stability of the system. Super-twisting sliding mode control (STSMC) has strong robustness, which can effectively reduce system chattering, and improve control accuracy and system performance. The gain of the integral term in the STSMC is set as a constant, and the other gain is changed adaptively whose adaptive rate is deduced through the stability proof of the neural network, which greatly reduces the difficulty of parameter adjustment. The harmonic suppression ability of the designed control strategy is verified by simulation experiments.
Higher Monotonicity Properties for Zeros of Certain Sturm-Liouville Functions
Authors: Tsai Tzong-Mo
Published: June 2023

In this paper, we consider the differential equation y″+ω2ρ(x)y=0, where ω is a positive parameter. The principal concern here is to find conditions on the function ρ−1/2(x) which ensure that the consecutive differences of sequences constructed from the zeros of a nontrivial solution of the equation are regular in sign for sufficiently large ω. In particular, if cνk(α) denotes the kth positive zero of the general Bessel (cylinder) function Cν(x;α)=Jν(x)cosα−Yν(x)sinα of order ν and if |ν|<1/2, we prove that (−1)mΔm+2cνk(α)>0(m=0,1,2,…;k=1,2,…), where Δak=ak+1−ak. This type of inequalities was conjectured by Lorch and Szego in 1963. In addition, we show that the differences of the zeros of various orthogonal polynomials with higher degrees possess sign regularity.
Sequential Extraction of Valuable Bio-Products from Snow Crab (Chionoecetes opilio) Processing Discards Using Eco-Friendly Methods
Authors: Burke Heather J. , Kerton Francesca
Published: June 2023

Green extraction methods using a combination of mechanical, enzymatic, and green chemical treatments were evaluated for the sequential extraction of carotenoid pigments, protein, and chitin from crab processing discards. Key objectives included avoiding the use of hazardous chemical solvents, conducting as close to a 100% green extraction as possible, and developing simple processes to facilitate implementation into processing plants without the need for complicated and expensive equipment. Three crab bio-products were obtained: pigmented vegetable oil, pigmented protein powder, and chitin. Carotenoid extractions were performed using vegetable oils (corn, canola, and sunflower oils), giving between 24.85% and 37.93% astaxanthin recovery. Citric acid was used to demineralize the remaining material and afforded a pigmented protein powder. Three different proteases were used to deproteinate and isolate chitin in yields between 17.06% and 19.15%. The chitin was still highly colored and therefore decolorization was attempted using hydrogen peroxide. Characterization studies were conducted on each of the crab bio-products isolated including powder X-ray diffraction analysis on the chitin (80.18% crystallinity index, CI, achieved using green methods). Overall, three valuable bio-products could be obtained but further research is needed to obtain pigment-free chitin in an environmentally friendly manner.
Gut Microbiota and Neuroinflammation in Acute Liver Failure and Chronic Liver Disease
Authors: Giuli Lucia , Maestri Marta , Santopaolo Francesco , Pompili Maurizio , Ponziani Francesca Romana
Published: June 2023

Acute liver failure and chronic liver disease are associated with a wide spectrum of neurological changes, of which the best known is hepatic encephalopathy (HE). Historically, hyperammonemia, causing astrocyte swelling and cerebral oedema, was considered the main etiological factor in the pathogenesis of cerebral dysfunction in patients with acute and/or chronic liver disease. However, recent studies demonstrated a key role of neuroinflammation in the development of neurological complications in this setting. Neuroinflammation is characterized by activation of microglial cells and brain secretion of pro-inflammatory cytokines, such as tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6, which alter neurotransmission, leading to cognitive and motor dysfunction. Changes in the gut microbiota resulting from liver disease play a crucial role in the pathogenesis of neuroinflammation. Dysbiosis and altered intestinal permeability, resulting in bacterial translocation and endotoxemia, are responsible for systemic inflammation, which can spread to brain tissue and trigger neuroinflammation. In addition, metabolites derived from the gut microbiota can act on the central nervous system and facilitate the development of neurological complications, exacerbating clinical manifestations. Thus, strategies aimed at modulating the gut microbiota may be effective therapeutic weapons. In this review, we summarize the current knowledge on the role of the gut–liver–brain axis in the pathogenesis of neurological dysfunction associated with liver disease, with a particular focus on neuroinflammation. In addition, we highlight emerging therapeutic approaches targeting the gut microbiota and inflammation in this clinical setting.