bluuebunny/crossref_metadata_2025 huggingface dataset:
Antibiotics in Dentistry: A Narrative Review of the Evidence beyond the Myth
Authors: Contaldo Maria , D’Ambrosio Francesco , Ferraro Giuseppe A. , Di Stasio Dario , Di Palo Maria Pia , Serpico Rosario , Simeone Michele
Published: June 2023

Antibiotics have undoubtedly revolutionized medicine and the health and survival of patients with life-threatening infections, being nonetheless free from potential adverse effects, and the risk of intestinal dysbiosis, antimicrobial resistance, and the resulting consequences for the patient’s health and the public purse. The present study narratively reviewed the epidemiological data on worldwide antibiotic consumption and administration in dental practice, patients’ adherence to prescriptions, the antimicrobial resistance phenomenon in dentistry, and the evidence supporting and recommending appropriate antibiotic use in dental care. Eligible systematic reviews and original studies in humans published in the English language from January 2000 to 26 January 2023 were considered. A total of 78 studies, 47 on the epidemiology of antibiotic use and prescription in dentistry, 6 on antibiotic therapy in dentistry, 12 on antibiotic prophylaxis in dentistry, 0 on adherence of dental patients to antibiotic prescription, and 13 on antimicrobial resistance in dentistry, were presently considered. Retrieved evidence revealed that antibiotics are frequently overused and misused in dental practice, dental patients frequently do not adhere to prescriptions, and antimicrobial resistance in dentistry is a still rising phenomenon also secondary to improper oral antiseptics use. The present findings highlighted the need to establish more evidence-based and accurate antibiotic prescriptions to sensitize dentists and dental patients to minimize and rationalize the use of antibiotics only when it is indicated and necessary, improve patients’ adherence, and enhance knowledge and awareness of the antimicrobial resistance in dentistry.
Skeletal Muscle Transcriptome Alterations Related to Declining Physical Function in Older Mice
Authors: Graber Ted G. , Maroto Rosario , Thompson Jill K. , Widen Steven G. , Man Zhaohui , Pajski Megan L. , Rasmussen Blake B.
Published: June 2023

One inevitable consequence of aging is the gradual deterioration of physical function and exercise capacity, driven in part by the adverse effect of age on muscle tissue. We hypothesized that relationships exist between age-related differentially expressed genes (DEGs) in skeletal muscle and age-associated declines in physical function and exercise capacity. Previously, male C57BL/6mice (6m, months old, 24m, and 28m) were tested for physical function using a composite scoring system (comprehensive functional assessment battery, CFAB) comprised of five well-validated tests of physical function. In this study, total RNA was isolated from tibialis anterior samples (n = 8) randomly selected from each age group in the parent study. Using Next Generation Sequencing RNAseq to determine DEGs during aging (6m vs. 28m, and 6m vs. 24m), we found a greater than five-fold increase in DEGs in 28m compared to the 24m. Furthermore, regression of the normalized expression of each DEG with the CFAB score of the corresponding mouse revealed many more DEGs strongly associated (R ≥ |0.70|) with functional status in the older mice. Gene ontology results indicate highly enriched axon guidance and acetyl choline receptor gene sets, suggesting that denervation/reinnervation flux might potentially play a critical role in functional decline. We conclude that specific age-related DEG patterns are associated with declines in physical function, and the data suggest accelerated aging occurring between 24 and 28 months.
Hemiplegic Migraine in Children and Adolescents
Authors: Bonemazzi Ilaria , Brunello Francesco , Pin Jacopo Norberto , Pecoraro Mattia , Sartori Stefano , Nosadini Margherita , Toldo Irene
Published: June 2023

Background: Only a few studies have focused on hemiplegic migraine (HM) in children despite its early age of onset. The aim of this review is to describe the peculiar characteristics of pediatric HM. Methods: This is a narrative review based on 14 studies on pediatric HM selected from 262 papers. Results: Different from HM in adults, pediatric HM affects both genders equally. Early transient neurological symptoms (prolonged aphasia during a febrile episode, isolated seizures, transient hemiparesis, and prolonged clumsiness after minor head trauma) can precede HM long before its onset. The prevalence of non-motor auras among children is lower than it is in adults. Pediatric sporadic HM patients have longer and more severe attacks compared to familial cases, especially during the initial years after disease onset, while familial HM cases tend to have the disease for longer. During follow-up, the frequency, intensity, and duration of HM attacks often decrease. The outcome is favorable in most patients; however, neurological conditions and comorbidities can be associated. Conclusion: Further studies are needed to better define the clinical phenotype and the natural history of pediatric HM and to refine genotype–phenotype correlations in order to improve the knowledge on HM physiopathology, diagnosis, and outcome.
Dual-Source Photon-Counting Computed Tomography—Part III: Clinical Overview of Vascular Applications beyond Cardiac and Neuro Imaging
Authors: Meloni Antonella , Cademartiri Filippo , Pistoia Laura , Degiorgi Giulia , Clemente Alberto , De Gori Carmelo , Positano Vincenzo , Celi Simona , Berti Sergio , Emdin Michele , Panetta Daniele , Menichetti Luca , Punzo Bruna , Cavaliere Carlo , Bossone Eduardo , Saba Luca , Cau Riccardo , La Grutta Ludovico , Maffei Erica
Published: June 2023

Photon-counting computed tomography (PCCT) is an emerging technology that is expected to radically change clinical CT imaging. PCCT offers several advantages over conventional CT, which can be combined to improve and expand the diagnostic possibilities of CT angiography. After a brief description of the PCCT technology and its main advantages we will discuss the new opportunities brought about by PCCT in the field of vascular imaging, while addressing promising future clinical scenarios.
Studies of Utilization of Technogenic Raw Materials in the Synthesis of Cement Clinker from It and Further Production of Portland Cement
Authors: Zhanikulov Nurgali , Sapargaliyeva Bayan , Agabekova Aktolkyn , Alfereva Yana , Baidibekova Aidin , Syrlybekkyzy Samal , Nurshakhanova Lazzat , Nurbayeva Farida , Sabyrbaeva Gulzhan , Zhatkanbayev Yergazy , Kozlov Pavel , Izbassar Aizhan , Kolesnikova Olga
Published: June 2023

Four series of experiments were carried out to study the possibility of replacing clay and an iron-containing component with tefritobasalt and lead slag as part of the initial charge for Portland cement. The experiments were carried out at atmospheric pressure and a temperature of 1350 °C. It was shown that the replacement of clay and an iron-containing component with tefritobasalt and lead slag as part of the initial charge in the cement industry will lead to a decrease in temperature by 100 °C in the technological scheme of production and a reduction in energy consumption, since the theoretical specific consumption of raw materials is 1.481 t/t of clinker, which is approximately 70 kg lower than in traditional mixtures. The content of non-traditional components in total was 24.69%. In addition, tefritobasalts improved clinker formation processes, contributed to a decrease in the firing temperature, and intensified the clinker firing process. A small amount of lead slag (5.06%) introduced into the mixture changed the structure of the clinker and improved the process of mineral formation while also improving roasting and reducing the anthropogenic impact on the environment through the disposal of man-made waste. The strength of the experimental composite cements was tested after 7 and 28 days on small samples measuring 2 × 2 × 2 cm. The physicomechanical characteristics and structure of composite cements were studied.
Green Ultrasound-Assisted Synthesis of Surface-Decorated Nanoparticles of Fe3O4 with Au and Ag: Study of the Antifungal and Antibacterial Activity
Authors: Ruíz-Baltazar Álvaro de Jesús , Böhnel Harald Norbert , Larrañaga Ordaz Daniel , Cervantes-Chávez José Antonio , Méndez-Lozano Néstor , Reyes-López Simón Yobanny
Published: June 2023

This work proposes a sonochemical biosynthesis of magnetoplasmonic nanostructures of Fe3O4 decorated with Au and Ag. The magnetoplasmonic systems, such as Fe3O4 and Fe3O4-Ag, were characterized structurally and magnetically. The structural characterizations reveal the magnetite structures as the primary phase. Noble metals, such as Au and Ag, are present in the sample, resulting in a structure-decorated type. The magnetic measurements indicate the superparamagnetic behavior of the Fe3O4-Ag and Fe3O4-Au nanostructures. The characterizations were carried out by X-ray diffraction and scanning electron microscopy. Complementarily, antibacterial and antifungal assays were carried out to evaluate the potential properties and future applications in biomedicine.
Terahertz Constant Velocity Flying Spot for 3D Tomographic Imaging
Authors: Aouali Abderezak , Chevalier Stéphane , Sommier Alain , Pradere Christophe
Published: June 2023

This work reports on a terahertz tomography technique using constant velocity flying spot scanning as illumination. This technique is essentially based on the combination of a hyperspectral thermoconverter and an infrared camera used as a sensor, a source of terahertz radiation held on a translation scanner, and a vial of hydroalcoholic gel used as a sample and mounted on a rotating stage for the measurement of its absorbance at several angular positions. From the projections made in 2.5 h and expressed in terms of sinograms, the 3D volume of the absorption coefficient of the vial is reconstructed by a back-projection method based on the inverse Radon transform. This result confirms that this technique is usable on samples of complex and nonaxisymmetric shapes; moreover, it allows 3D qualitative chemical information with a possible phase separation in the terahertz spectral range to be obtained in heterogeneous and complex semitransparent media.
An Enhanced Photogrammetric Approach for the Underwater Surveying of the Posidonia Meadow Structure in the Spiaggia Nera Area of Maratea
Authors: Russo Francesca , Del Pizzo Silvio , Di Ciaccio Fabiana , Troisi Salvatore
Published: June 2023

The Posidonia oceanica meadows represent a fundamental biological indicator for the assessment of the marine ecosystem’s state of health. They also play an essential role in the conservation of coastal morphology. The composition, extent, and structure of the meadows are conditioned by the biological characteristics of the plant itself and by the environmental setting, considering the type and nature of the substrate, the geomorphology of the seabed, the hydrodynamics, the depth, the light availability, the sedimentation speed, etc. In this work, we present a methodology for the effective monitoring and mapping of the Posidonia oceanica meadows by means of underwater photogrammetry. To reduce the effect of environmental factors on the underwater images (e.g., the bluish or greenish effects), the workflow is enhanced through the application of two different algorithms. The 3D point cloud obtained using the restored images allowed for a better categorization of a wider area than the one made using the original image elaboration. Therefore, this work aims at presenting a photogrammetric approach for the rapid and reliable characterization of the seabed, with particular reference to the Posidonia coverage.
Influence of Horizontal Loading in Changing the Ultimate Uplift Bearing Capacity of Monopile Foundation of Offshore Wind Turbine
Authors: Sun Yong-Xin , Wang Zhi-Peng , Dou Hong-Qiang , Qu Zhan-Fei , Xue Bing-Lei , Feng Ling-Yun
Published: June 2023

Throughout their lifespan, monopile foundations supporting offshore wind turbines inevitably experience horizontal loads from waves, winds, and currents, resulting in cumulative deformation. It has been believed that deformation caused by horizontal loading weakens the interaction between the pile and the soil, leading to a reduction in the ultimate uplift bearing capacity of the pile foundation. However, there is a scarcity of literature investigating this issue, particularly regarding monopiles used in offshore wind turbine installations. Therefore, this study aims to explore the impact of horizontal cyclic loads on the ultimate uplift bearing capacity of monopile, focusing on the pile–soil interaction. To achieve this, a series of 1 g model tests were conducted on a rigid model pile embedded in silt with varying relative compaction. The test results indicate that the ultimate uplift bearing capacity of the pile is significantly diminished after experiencing horizontal cyclic loading, and the extent of reduction is closely linked to the amplitude of the horizontal deformation. A semi-empirical model is developed to predict the ultimate uplift bearing capacity of the pile foundation following horizontal cyclic loading. The key findings of this study are as follows: (1) The earth pressure in the active zone gradually decreases with an increasing number of cycles, while the earth pressure in the passive zone experiences a slight increase under horizontal cyclic loading. (2) The position of the pile rotation center under horizontal cyclic loading is approximately 0.84 times the depth at which the pile is buried, and this relationship appears to be independent of soil density and cyclic load ratio. (3) The variation of earth pressure corresponding to the horizontal deformation of the pile in the active zone can be divided into three phases: a rapid decline phase, a slow decline phase, and a stable phase. (4) The reduction in the ultimate uplift capacity is influenced by the cyclic ratio and number of cycles but does not appear to have a significant relationship with soil density.
Coordinated Obstacle Avoidance of Multi-AUV Based on Improved Artificial Potential Field Method and Consistency Protocol
Authors: Yu Haomiao , Ning Luqian
Published: June 2023

Formation avoidance is one of the critical technologies for autonomous underwater vehicle (AUV) formations. To this end, a cooperative obstacle avoidance algorithm based on an improved artificial potential field method and a consistency protocol is proposed in this paper for the local obstacle avoidance problem of AUV formation. Firstly, for the disadvantage that the traditional artificial potential field method can easily fall into local minima, an auxiliary potential field perpendicular to the AUV moving direction is designed to solve the problem that AUVs can easily have zero combined force in the potential field and local minima. Secondly, the control law of AUV formation that keeps the speed and position consistent is designed for the problem that the formation will change during the local obstacle avoidance of the formation system. The control conflict problem of the combined algorithm of the artificial potential field law and the consistency protocol is solved by adjusting the desired formation of the consistency protocol through the potential field force. Finally, the bounded energy function demonstrates system convergence stability. The simulation verification confirmed that the AUV formation could achieve the convergence of the formation state under local obstacle avoidance.
Microbial Biological Control of Fungi Associated with Grapevine Trunk Diseases: A Review of Strain Diversity, Modes of Action, and Advantages and Limits of Current Strategies
Authors: Mesguida Ouiza , Haidar Rana , Yacoub Amira , Dreux-Zigha Assia , Berthon Jean-Yves , Guyoneaud Rémy , Attard Eléonore , Rey Patrice
Published: June 2023

Grapevine trunk diseases (GTDs) are currently among the most important health challenges for viticulture in the world. Esca, Botryosphaeria dieback, and Eutypa dieback are the most current GTDs caused by fungi in mature vineyards. Their incidence has increased over the last two decades, mainly after the ban of sodium arsenate, carbendazim, and benomyl in the early 2000s. Since then, considerable efforts have been made to find alternative approaches to manage these diseases and limit their propagation. Biocontrol is a sustainable approach to fight against GTD-associated fungi and several microbiological control agents have been tested against at least one of the pathogens involved in these diseases. In this review, we provide an overview of the pathogens responsible, the various potential biocontrol microorganisms selected and used, and their origins, mechanisms of action, and efficiency in various experiments carried out in vitro, in greenhouses, and/or in vineyards. Lastly, we discuss the advantages and limitations of these approaches to protect grapevines against GTDs, as well as the future perspectives for their improvement.
Insights into Diversity, Distribution, and Systematics of Rust Genus Puccinia
Authors: Avasthi Shubhi , Gautam Ajay Kumar , Niranjan Mekala , Verma Rajnish Kumar , Karunarathna Samantha C. , Kumar Ashwani , Suwannarach Nakarin
Published: June 2023

Puccinia, which comprises 4000 species, is the largest genus of rust fungi and one of the destructive plant pathogenic rust genera that are reported to infect both agricultural and nonagricultural plants with severe illnesses. The presence of bi-celled teliospores is one of the major features of these rust fungi that differentiated them from Uromyces, which is another largest genus of rust fungi. In the present study, an overview of the current knowledge on the general taxonomy and ecology of the rust genus Puccinia is presented. The status of the molecular identification of this genus along with updated species numbers and their current statuses in the 21st century are also presented, in addition to their threats to both agricultural and nonagricultural plants. Furthermore, a phylogenetic analysis based on ITS and LSU DNA sequence data available in GenBank and the published literature was performed to examine the intergeneric relationships of Puccinia. The obtained results revealed the worldwide distribution of Puccinia. Compared with other nations, a reasonable increase in research publications over the current century was demonstrated in Asian countries. The plant families Asteraceae and Poaceae were observed as the most infected in the 21st century. The phylogenetic studies of the LSU and ITS sequence data revealed the polyphyletic nature of Puccinia. In addition, the presences of too short, too lengthy, and incomplete sequences in the NCBI database demonstrate the need for extensive DNA-based analyses for a better understanding of the taxonomic placement of Puccinia.
Spatial Patterns of Planktonic Fungi Indicate Their Potential Contributions to Biological Carbon Pump and Organic Matter Remineralization in the Water Column of South China Sea
Authors: Sen Kalyani , Bai Mohan , Li Jiaqian , Ding Xueyan , Sen Biswarup , Wang Guangyi
Published: June 2023

Fungi have long been known to be dynamic in coastal water columns with multiple trophic modes. However, little is known about their interactions with abiotic and biotic components, contribution to the biological carbon pump (BCP), and organic matter remineralization in the oceanic water column. In this study, we investigated how fungi vary spatially and how their variations relate to that of bacteria in the water column of the South China Sea (SCS). Fungi were about three orders less prevalent than bacteria, and the main factors influencing their distribution were depth, temperature, and distance from the sites of riverine inputs. The decline in the abundance of fungi with depth was less steep than that of bacteria. Correlation tests revealed a strong positive association between the abundance of fungi and bacteria, especially in the twilight (r = 0.62) and aphotic (r = 0.70) zones. However, the co-occurrence network revealed mutual exclusion between certain members of fungi and bacteria. The majority of fungi in the water column were saprotrophs, which indicated that they were generally involved in the degradation of organic matter, particularly in twilight and aphotic zones. Similar to bacteria, the involvement of fungi in the metabolism of carbohydrates, proteins, and lipids was predicted, pointing to their participation in the turnover of organic carbon and the biogeochemical cycling of carbon, nitrogen, and sulfur. These findings suggest that fungi play a role in BCP and support their inclusion in marine microbial ecosystem models.
Is Beauty a Matter of Volume Distribution? Proposal of a New Aesthetic Three-Dimensional Guide in Orthognathic Surgery
Authors: Bianchi Alberto , Seidita Francesco , Badiali Giovanni , Lusetti Laura , Saporosi Cristiana , Pironi Marco , Marchetti Claudio , Crimi Salvatore
Published: June 2023

Background: Orthognathic surgery is a multidisciplinary surgery in which the aesthetic results have become increasingly important, and consequently, also the predictability of the surgical outcomes. In this paper, we analyzed the volumetric distribution of the lower two-thirds of the face, in patients operated by orthognathic surgery and selected for their attractiveness. Our goal was to analyze the aesthetic volumetric distribution for gender and to propose our operating philosophy, that a normative distribution of facial volumes could be used like a new 3D aesthetic guide in orthognathic planning. Methods: A group of 46 orthognathic patients (26 females, 20 males) with the best postoperative aesthetic score was selected by a jury of plastic surgeons, orthodontists, and journalists. The mean soft tissue volumes of the malar, maxillary, mandibular, and chin regions were analyzed. Results: Overall, we measured a mean female facial volume distribution of 38.7%, 29%, 27.6%, and 4.7%, respectively, in the malar, maxillary, mandibular, and chin regions, while in males, it was 37%, 26%, 30%, and 6%, respectively. Conclusions: In this paper, the expansion of facial volumes in orthognathic surgery is proposed as a key point for facial harmonization. Beauty could be scientifically interpreted as a balanced distribution of facial volumes, and the virtual study of this distribution can become an important part of the preoperative analysis, such as a “volumetric” 3D cephalometry, where the surgeon could use average values of aesthetic volumetric distribution as preoperative surgical references.
Background Conditions for Revitalisation Processes in the Case of Unused Public Buildings in Italy: An Ostromian Perspective
Authors: Bellè Beatrice Maria
Published: June 2023

In Italy, the number of buildings that have fallen into disuse is huge. Moreover, the normative and regulative framework promoting the public portfolio’s re-use and revitalisation is still unclear and ambiguous. Nevertheless, over the past decade, these buildings have become fertile ground for innovation and creative experiences led by civic actors. The rise of this new category of civic actors plays an important role, both in terms of the institutional dynamics and the kind of initiatives and practices they undertake. Although they act in different manners, they share similar patterns of behaviour validated through an in-depth analysis. This research pinpointed that, regardless of the diverse operating contexts, institutional performances can be successful only if certain kinds of conditions are considered. This paper has a twofold aim: (i) to establish an analytical framework for analysing the emerging streamlined phenomenon of revitalisation processes in unused public buildings, (ii) and to critically discuss these processes, providing key insights into behaviour and institutional civic actors’ performances, as well as the necessary conditions for successful revitalisation. By doing so, this paper aims to enhance our understanding of civic actors and their role in revitalisation processes, contributing to discussing and identifying crucial factors for achieving a successful outcome.
Characterization of Malectin/Malectin-like Receptor-like Kinase Family Members in Foxtail Millet (Setaria italica L.)
Authors: Jing Xiuqing , Deng Ning , Shalmani Abdullah
Published: June 2023

Plant malectin/malectin-like receptor-like kinases (MRLKs) play crucial roles throughout the life course of plants. Here, we identified 23 SiMRLK genes from foxtail millet. All the SiMRLK genes were named according to the chromosomal distribution of the SiMRLKs in the foxtail millet genome and grouped into five subfamilies based on phylogenetic relationships and structural features. Synteny analysis indicated that gene duplication events may take part in the evolution of SiMRLK genes in foxtail millet. The expression profiles of 23 SiMRLK genes under abiotic stresses and hormonal applications were evaluated through qRT-PCR. The expression of SiMRLK1, SiMRLK3, SiMRLK7 and SiMRLK19 were significantly affected by drought, salt and cold stresses. Exogenous ABA, SA, GA and MeJA also obviously changed the transcription levels of SiMRLK1, SiMRLK3, SiMRLK7 and SiMRLK19. These results signified that the transcriptional patterns of SiMRLKs showed diversity and complexity in response to abiotic stresses and hormonal applications in foxtail millet.
The Immunotherapeutic Role of Type I and III Interferons in Melanoma and Non-Melanoma Skin Cancers
Authors: Weir Sydney A. , KC Kailash , Shoaib Shoaib , Yusuf Nabiha
Published: June 2023

Interferons (IFNs) have demonstrated therapeutic potential in various skin cancers, specifically squamous cell carcinoma (SCC), basal cell carcinoma (BCC), and melanoma. The precise mechanism through which type I IFNs exert their antitumor effects in skin cancers is still being studied. However, intralesional type I IFN can be used as an alternative to surgery for select patient populations, and high-dose systemic IFN therapy has been shown to be promising in patients with operable high-risk or metastatic melanoma. Despite the therapeutic potential of IFNs in skin cancer treatment, the toxicity profile often prevents the completion of treatment and further expansion of its clinical application. Type I and III IFNs use the same Janus Kinases (JAKs) for signal transduction, which are pathways initiated at a cell surface receptor that mediates the activation of target genes in the nucleus, based on this shared signaling pathway. Due to selective tumor targeting and the ability to generate both innate and adaptive immune responses, we concluded that type III IFNs have minimal side effects compared with established treatments due to selective tumor targeting. While IFN-λ, a type III IFN, shows therapeutic potential as stand-alone or in combination with another IFN, further studies need to be conducted to explore the therapeutic potential of IFN-λ in skin cancer and the underlying physiological roles and mechanisms of action. In this review, we evaluate whether treatment of skin cancer with type III IFN will have minimal side effects compared with established treatments.
Synergistic Lubrication Mechanism of Nano-Fluid and Grinding Wheel Prepared by CNTs@T304 Nano-Capsules
Authors: Guan Jiju , Zhu Zhengbing , Yang Lanyu , Xia Yu , Xu Xuefeng , Huang Shuiquan
Published: June 2023

Grinding fluid often struggles to enter the grinding area and overcoming this challenge has been a major focus of research in recent years. Therefore, CNTs@T304 nano-capsules are prepared by filling the cavities of CNTs with a lubricant of T304. CNTs@T304 nano-capsules were used as an additive in this paper to prepare resin grinding wheels and nanofluids, respectively. The resin wheels filled with nano-capsules were used for grinding under the lubrication of nanofluids, and T304 could then be released to the grinding area to play a self-lubricating role during grinding. First, CNTs@T304 nano-capsules were characterized, and the properties of the prepared grinding wheels and nanofluids were tested. Second, the effects of the filling of nano-capsules and grinding speed on the grinding force, grinding temperature, surface roughness, and grinding ratio were studied. Finally, the lubrication mechanism of the nano-capsules was revealed through surface analysis of the workpiece. The results suggested that nano-capsules had good thermal stability and the nanofluid prepared from them exhibited good dispersion stability and thermal conductivity. The grinding wheel was found to satisfy the service conditions when the filling content was less than 15%. Compared with a common wheel, the grinding force and grinding temperature were reduced by 24% and 28%, respectively, and the surface roughness of the workpiece and the grinding ratio were increased by 18% and by 21%, respectively, when grinding GCr15 steel with the nano-capsule wheel. Lubrication with nanofluids could further reduce the grinding force, grinding temperature, and surface roughness values. During grinding, the self-lubrication film formed by the T304 released from the nano-capsules in the wheel served first and foremost as a lubricant. The intervention of the nanofluid enhanced the heat-exchange effect and lubrication efficiency in the grinding zone.
Investigation of Crack Propagation Behaviour in Thin-Rim Gears: Experimental Tests and Numerical Simulations
Authors: He Haifeng , Mura Andrea , Zhang Taihua , Liu Heli , Xu Weiping
Published: June 2023

Thin-rim gears are widely used in industrial fields such as aerospace and electric vehicles due to the advantage of light weight. Yet, the root crack fracture failure of thin-rim gears significantly limits their application and further affects the reliability and safety of high-end equipment. In this work, the root crack propagation behavior of thin-rim gears is experimentally and numerically investigated. The crack initiation position and crack propagation path for different backup ratio gears are simulated using gear finite element (FE) models. The crack initiation position is determined using the maximum gear root stress position. An extended FE method coupled with commercial software ABAQUS is used to simulate the gear root crack propagation. The simulation results are then verified by conducting experimental tests for different backup ratio gears based on a dedicated designed single-tooth bending test device.
Prediction Model Based on DoE and FTIR Data to Control Fast Setting and Early Shrinkage of Alkaline-Activated Slag/Silica Fume Blended Cementitious Material
Authors: Schade Tim , Middendorf Bernhard
Published: June 2023

This study aims to develop a material-saving performance prediction model for fast-hardening alkali-activated slag/silica fume blended pastes. The hydration process in the early stage and the microstructural properties after 24 h were analyzed using design of experiments (DoE). The experimental results show that the curing time and the FTIR wavenumber of the Si-O-T (T = Al, Si) bond in the band range of 900–1000 cm−1 after 24 h can be predicted accurately. In detailed investigations, low wavenumbers from FTIR analysis were found to correlate with reduced shrinkage. The activator exerts a quadratic and not a silica modulus-related conditioned linear influence on the performance properties. Consequently, the prediction model based on FTIR measurements proved to be suitable in evaluation tests for predicting the material properties of those binders in the building chemistry sector.
Numerical Modeling for the Prediction of Microstructure and Mechanical Properties of Quenched Automotive Steel Pieces
Authors: Coroas Carlos , Viéitez Iván , Martín Elena , Román Manuel
Published: June 2023

In this work, we present an efficient numerical tool for the prediction of the final microstructure, mechanical properties, and distortions of automotive steel spindles subjected to quenching processes by immersion in liquid tanks. The complete model, which consists of a two-way coupled thermal–metallurgical model and a subsequent (one-way coupled) mechanical model, was numerically implemented using finite element methods. The thermal model includes a novel generalized solid-to-liquid heat transfer model that depends explicitly on the piece’s characteristic size, the physical properties of the quenching fluid, and quenching process parameters. The resulting numerical tool is experimentally validated by comparison with the final microstructure and hardness distributions obtained on automotive spindles subjected to two different industrial quenching processes: (i) a batch-type quenching process with a soaking air-furnace stage prior to the quenching, and (ii) a direct quenching process where the pieces are submerged directly in the liquid just after forging. The complete model retains accurately, at a reduced computational cost, the main features of the different heat transfer mechanisms, with deviations in the temperature evolution and final microstructure lower than 7.5% and 12%, respectively. In the framework of the increasing relevance of digital twins in industry, this model is a useful tool not only to predict the final properties of quenched industrial pieces but also to redesign and optimize the quenching process.
Mechanical Resistance and Tissue Structure of Claw Denticles of Various Sizes in the Mud Crab, Scylla serrata
Authors: Inoue Tadanobu , Hara Yuka , Nakazato Koji
Published: June 2023

Decapod crustaceans have tooth-like denticles on their claw fingers, which come into direct contact with predators and prey. Since the denticles are subject to more frequent and intense stress than other parts of the exoskeleton, they must be especially resistant to wear and abrasion. We clarified the mechanical resistance and tissue structure of the denticles arranged in a line on the fixed finger of the mud crab, which has huge claws. The denticles of the mud crab are small at the fingertip and become larger closer to the palm. The denticles have a twisted-plywood-pattern structure stacked parallel to the surface regardless of size, but the abrasion resistance strongly depends on the size of the denticles. Due to the dense tissue structure and calcification, the abrasion resistance increases as the denticle size increases, reaching its maximum at the denticle surface. The denticles of the mud crab have a tissue structure that prevents them from breaking when pinched. The high abrasion resistance of the large denticle surface is an essential feature for the frequent crushing of shellfish, which is the mud crab’s staple food. The characteristics and tissue structure of the claw denticles on the mud crab may provide ideas for developing stronger, tougher materials.
Microstructure, Mechanical and Tribological Properties of High-Entropy Carbide (MoNbTaTiV)C5
Authors: Zhang Shubo , Qin Falian , Gong Maoyuan , Wu Zihao , Liu Meiling , Chen Yuhong , Hai Wanxiu
Published: June 2023

High-entropy carbide (NbTaTiV)C4 (HEC4), (MoNbTaTiV)C5 (HEC5), and (MoNbTaTiV)C5-SiC (HEC5S) multiphase ceramics were prepared by spark plasma sintering (SPS) at 1900 to 2100 °C, using metal carbide and silicon carbide (SiC) as raw materials. Their microstructure, and mechanical and tribological properties were investigated. The results showed that the (MoNbTaTiV)C5 synthesized at 1900–2100 °C had a face-centered cubic structure and density higher than 95.6%. The increase in sintering temperature was conducive to the promotion of densification, growth of grains, and diffusion of metal elements. The introduction of SiC helped to promote densification but weakened the strength of the grain boundaries. The average specific wear rates for HEC4 were within an order of magnitude of 10−5 mm3/N·m, and for HEC5 and HEC5S were within a range of 10−7 to 10−6 mm3/N·m. The wear mechanism of HEC4 was abrasion, while that of HEC5 and HEC5S was mainly oxidation wear.
Tension Stiffening and Cracking Behavior of Axially Loaded Alkali-Activated Concrete
Authors: Abdulrahman Hamdi , Muhamad Rahimah , Shukri Ahmad Azim , Al-Fakih Amin , Alqaifi Gamal , Mutafi Ayad , Al-Duais Husam S. , Al-Sabaeei Abdulnaser M.
Published: June 2023

Alkali-activated concrete is an eco-friendly construction material that is used to preserve natural resources and promote sustainability in the construction industry. This emerging concrete consists of fine and coarse aggregates and fly ash that constitute the binder when mixed with alkaline activators, such as sodium hydroxide (NaOH) and sodium silicate (Na2SiO3). However, understanding its tension stiffening and crack spacing and width is of critical importance in fulfilling serviceability requirements. Therefore, this research aims to evaluate the tension stiffening and cracking performance of alkali-activated (AA) concrete. The variables considered in this study were compressive strength (fc) and concrete cover-to-bar diameter (Cc/db) ratios. After casting the specimen, they were cured before testing at ambient curing conditions for 180 days to reduce the effects of concrete shrinkage and obtain more realistic cracking results. The results showed that both AA and OPC concrete prisms develop slightly similar axial cracking force and corresponding cracking strain, but OPC concrete prisms exhibited a brittle behavior, resulting in a sudden drop in the load–strain curves at the crack location. In contrast, AA concrete prisms developed more than one crack simultaneously, suggesting a more uniform tensile strength compared to OPC specimens. The tension-stiffening factor (β) of AA concrete exhibited better ductile behavior than OPC concrete due to the strain compatibility between concrete and steel even after crack ignition. It was also observed that increasing the confinement (Cc/db ratio) around the steel bar delays internal crack formation and enhances tension stiffening in AAC. Comparing the experimental crack spacing and width with the values predicted using OPC codes of practice, such as EC2 and ACI 224R, revealed that EC2 tends to underestimate the maximum crack width, while ACI 224R provided better predictions. Thus, models to predict crack spacing and width have been proposed accordingly.
The Effect of 10% Carbamide Peroxide Dental Bleaching on the Physical Properties of Invisalign Aligners: An In Vitro Study
Authors: Khashashneh Majd , Ratnayake Jithendra , Choi Joanne Jung Eun , Mei Li , Lyons Karl , Brunton Paul
Published: June 2023

The high aesthetic demands of patients have increased their requests to align their teeth using clear aligners, including Invisalign. Patients also want to have their teeth whitened for the same purpose; the use of Invisalign as a bleaching tray at night has been reported in few studies. However, whether 10% carbamide peroxide affects the physical properties of Invisalign is unknown. Therefore, the objective of this study was to evaluate the effect of 10% carbamide peroxide on the physical properties of Invisalign when used as a bleaching tray at night. Twenty-two unused Invisalign aligners (Santa Clara, CA, USA) were used to prepare 144 specimens to test their tensile strength, hardness, surface roughness, and translucency. The specimens were divided into four groups: a testing group at baseline (TG1), a testing group after application of bleaching material at 37 °C for 2 weeks (TG2), a control group at baseline (CG1), and a control group after immersion in distilled water at 37 °C for 2 weeks (CG2). Statistical analysis was conducted using a paired t-test, Wilcoxon signed rank test, independent samples t-test, and Mann–Whitney test to compare samples in CG2 to CG1, TG2 to TG1, and TG2 to CG2. Statistical analysis showed no statistically significant difference between the groups for all physical properties, except for hardness (p-value < 0.001) and surface roughness (p-value = 0.007 and p-value < 0.001 for the internal and external surface roughness, respectively), which revealed a reduction in hardness values (from 4.43 ± 0.86 N/mm2 to 2.2 ± 0.29 N/mm2) and an increase in surface roughness (from 1.6 ± 0.32 Ra to 1.93 ± 0.28 Ra and from 0.58 ± 0.12 Ra to 0.68 ± 0.13 Ra for the internal and external surface roughness, respectively) after 2 weeks of dental bleaching. Results showed that Invisalign can be used for dental bleaching without excessive distortion or degradation of the aligner material. However, future clinical trials are required to further assess the feasibility of using Invisalign for dental bleaching.
Stochastic Finite Element Analysis of Plate Structures Considering Spatial Parameter Random Fields
Authors: Yang Yan , Ge Fang-Wen , Liu Xiang
Published: June 2023

For plate structures, their random parameters can be regarded as a two-dimensional random field in the plane. To solve the plate theory considering a two-dimensional random field, an efficient strategy for the stochastic finite element method was adopted. Firstly, the stochastic finite element method was used to establish the plate structural model, in which the random field characteristics of the parameter were considered, and the mathematical expression of its random field was obtained through the Karhunen–Loève expansion; secondly, the point estimate method was applied to calculate the statistics of random structures. The computational efficiency can be significantly improved through the reference point selection strategy. The accuracy and efficiency of the calculation strategy were verified, and the influences of correlation length and coefficient of variation of the parameter on the random response of plate structures under different plate types (including Kirchhoff plate and Mindlin plate) and boundary conditions (including simply supported and clamped supported) were discussed. The proposed method can provide some help in solving static problems of plate structures.
Universal Bifurcation Chaos Theory and Its New Applications
Authors: Magnitskii Nikolai A.
Published: June 2023

In this work, an analytical and numerical analysis of the transition to chaos in five nonlinear systems of ordinary and partial differential equations, which are models of autocatalytic chemical processes and interacting populations, is carried out. It is shown analytically and numerically that in all considered systems of equations, further complication of the dynamics of solutions and the transition to chemical and biological turbulence is carried out in full accordance with the universal Feigenbaum-Sharkovsky-Magnitskii bifurcation theory through subharmonic and homoclinic cascades of bifurcations of stable limit cycles. In this case, irregular (chaotic) attractors in all cases are exclusively singular attractors in the sense of the FShM theory. The obtained results once again indicate the wide applicability of the universal bifurcation FShM theory for describing laminar–turbulent transitions to chaotic dynamics in complex nonlinear systems of differential equations and that chaos in the system can be confirmed only by detection of some main cycles or tori in accordance with the universal bifurcation diagram presented in the article.
Engaging STEM Learning Experience of Spatial Ability through Activities with Using Math Trail
Authors: Laššová Katarína , Rumanová Lucia
Published: June 2023

Math trail is a type of outdoor activity conducted in groups. Group members work together, communicate, and find common and best strategies for solving problems. Thus, it combines the use of mathematics in real life with a pleasant walk. Pupils have the opportunity to explore mathematics linked to real objects, solving standard and non-standard problems. Teachers, in turn, can use mathematics in this way as a tool to connect it to other STEM disciplines. This article first describes the results of research aimed at assessing spatial ability and mental rotation in students at technical vocational schools in Slovakia. A stereometry test was solved by 455 students. We then created a mathematical walk aimed at developing students’ spatial ability. The experiences presented in the article may be helpful as other mathematics’ popularization stimuli. We believe that when students are engaged in problem-based learning activities that are related to STEM disciplines, in particular, by connecting with the subjects in the problem context of the real world, STEM disciplines may become more important for students. Interdisciplinary STEM learning imitates authentic real-world problem-solving.
Gorenstein Flat Modules of Hopf-Galois Extensions
Authors: Guo Qiaoling , Shan Tingting , Shen Bingliang , Yang Tao
Published: June 2023

Let A/B be a right H-Galois extension over a semisimple Hopf algebra H. The purpose of this paper is to give the relationship of Gorenstein flat dimensions between the algebra A and its subalgebra B, and obtain that the global Gorenstein flat dimension and the finitistic Gorenstein flat dimension of A is no more than that of B. Then the problem of preserving property of Gorenstein flat precovers for the Hopf-Galois extension will be studied. Finally, more relations for the crossed products and smash products will be obtained as applications.
Equivalent-Input-Disturbance Based Robust Control Design for Fuzzy Semi-Markovian Jump Systems via the Proportional-Integral Observer Approach
Authors: Dharmarajan Aravindh , Arumugam Parivallal , Ramalingam Sakthivel , Ramasamy Kavikumar
Published: June 2023

This work focuses on the design of a unified control law, which enhances the accuracy of both the disturbance estimation and stabilization of nonlinear T-S fuzzy semi-Markovian jump systems. In detail, a proportional-integral observer based equivalent-input-disturbance (PIO-EID) approach is considered to model and develop the controller. The PIO approach includes a variable for relaxation in the system design along with an additional term for integration to improve the flexibility of the design and endurance of the system. The proposed stability criteria are formulated in the form of matrix inequalities using Lyapunov theory and depend on the sojourn time for robust control design. Final analyses are performed using MATLAB software with simulations to endorse the theoretical findings of this paper.
A Rare Co-Occurrence of Maffucci Syndrome and Astrocytoma with IDH1 R132H Mutation: A Case Report
Authors: Ashirov Nurali , Mammadinova Iroda , Moldabekov Aidos , Zhetpisbaev Berik , Teltayev Daniyar , Ryskeldiyev Nurzhan , Akshulakov Serik
Published: June 2023

Background: Maffucci syndrome is a rare genetic disorder associated with the development of multiple enchondromas and soft tissue cavernous hemangiomas, as well as an increased risk of malignant tumors. Case Description: Here we report a case of Maffucci syndrome in a patient who presented with a giant left frontal lobe tumor. Molecular genetic analysis of the tumor revealed an isocitrate dehydrogenase (IDH) mutation p.R132H (c.395C>A) mutation in the IDH1 gene and a heterozygous duplication of the CDKN2A genes. Conclusions: The presence of an IDH1 mutation is notable because this mutation is frequently seen in glial tumors and other neoplasms, and its co-occurrence with Maffucci syndrome may represent a novel risk factor for the development of gliomas. This case underscores the importance of genetic testing in patients with Maffucci syndrome who present with central nervous system tumors, as well as the need for further research to understand the relationship between IDH1 mutations and the development of gliomas in this population.