bluuebunny/crossref_metadata_2025 huggingface dataset:
Frontal Fibrosing Alopecia and Reproductive Health: Assessing the Role of Sex Hormones in Disease Development
Authors: Roman Alexandra-Maria , Petca Răzvan-Cosmin , Dumitrașcu Mihai Cristian , Petca Aida , Ionescu (Miron) Andreea-Iuliana , Șandru Florica
Published: January 2024

Frontal Fibrosing Alopecia (FFA) is a distinctive form of cicatricial alopecia characterized by gradual hairline recession, predominantly affecting postmenopausal individuals, thus implying a potential hormonal origin. This narrative review, spanning 2000 to 2023, delves into PubMed literature, focusing on the menopausal and hormonal status of women with FFA. The objective is to unravel the intricate nature of FFA and its plausible associations with hormonal dysregulations in women. While menopause remains a pivotal demographic characteristic linked to FFA, existing data suggest that its hormonal imbalances may not fully account for the development of FFA. Conversely, substantial evidence indicates a strong association between a reduction in fertile years, particularly through surgical interventions leading to an abrupt hormonal imbalance, and FFA in women. Additionally, exposure to hormone replacement therapy or oral contraceptives has shown varying degrees of association with FFA. Gynecologists should maintain a heightened awareness regarding the ramifications of their interventions and their pivotal role in overseeing women’s fertility, recognizing the potential influence on the progression of FFA. The recurrent theme of hormonal disruption strongly implies a causal connection between alterations in sex hormones and FFA in women. Nevertheless, this relationship’s extent and underlying mechanisms remain subjects of ongoing debate.
The Impact of Clinical Pharmacist Diabetes Education on Medication Adherence in Patients with Type 2 Diabetes Mellitus: An Interventional Study from Khartoum, Sudan
Authors: Badi Safaa , Suliman Sara Zainelabdein , Almahdi Rayan , Aldomah Mohammed A. , Marzouq Mohamed ELsir , Ibrahim Eiman Eltayeb M. , Ahmed Musaab , Ahmed Mohamed H. , Elkheir Habab Khalid , Ibrahim Mohamed Izham Mohamed
Published: January 2024

Background: Continuous therapeutic care with good medication adherence is the cornerstone of management of all chronic diseases including diabetes. This study aimed to evaluate the impact of clinical pharmacist intervention on the medication adherence in individuals with type 2 diabetes (T2DM). Methods: This was a randomized, double-blind, controlled trial conducted at a diabetes clinic located at Omdurman Military Hospital, Sudan. Individuals with T2DM attending the diabetes clinic within 1 year were selected. The sample size was 364 participants (182 control and 182 interventional group). We used a pre-structured standardized questionnaire and checklist to collect the data. Data were analyzed by using the Statistical Package for the Social Sciences (SPSS) (version 28). Results: Majority, 76.4% (n = 278) were females, and they consisted of 80.8% (n = 147) of the interventional group and 72% of the controls. The mean age of the interventional group was 54.5 (±10) years; 31.9% (n = 58) of the interventional group had diabetes for 6–10 years, compared with 26.4% (n = 48) of the control group. Among the control group, the mean adherence score was 6.8 (±1.7) at baseline and it was 6.7 (±1.6) at the end of the study (p < 0.001), while in the interventional group, the mean adherence score was 6.8 (±1.7) at baseline and it was 7.4 (±1.5) at the end of the study (p < 0.001). Conclusion: Adherence score among the intervention group was increased significantly from baseline to the end of the study when compared to the control group.
Rice Terrace Experience in Japan: An Ode to the Beauty of Seasonality and Nostalgia
Authors: Wang Qian , Yang Xiaoqi , Liu Xinyu , Furuya Katsunori
Published: January 2024

Rice terraces are a time-honored agricultural feature that overcomes rough terrain and hostile growing conditions. In addition to playing an essential role in agricultural production and land conservation, rice terraces have been recognized as living cultural landscapes, important agricultural heritage, and popular agritourism destinations for their aesthetic, sociocultural, and environmental values. However, there is a lack of understanding of this emerging niche market, especially from outsider perspectives. To fill the gap, this study analyzes Google Maps reviews of seventy representative rice terraces in Japan based on a mixed-method content analysis, aiming to identify visitors’ overall experiences, seasonal perceptions, and the causes of negative experiences. The results indicate that the overall experience of rice terraces in Japan includes seven themes: agricultural landscapes, times and seasons, visual perception, accessibility and infrastructure, sense of place, Genfukei of Japan, and food. Visitors’ perceptions toward the four seasons of the rice terraces have distinctive characteristics and result in different satisfaction levels. The main reasons for negative experiences are farmland abandonment, lack of character, poor accessibility, and bad timing. Leveraging the power of netnography, the study sheds light on the sustainable development of agricultural heritage tourism through the introduction of rice terrace conservation initiatives in Japan and the exploration of rice terrace experience.
Spatiotemporal Variation and Driving Factors Analysis of Habitat Quality: A Case Study in Harbin, China
Authors: Qi Yuxin , Hu Yuandong
Published: January 2024

Biodiversity is profoundly influenced by habitat quality, and Harbin, a provincial capital situated in a cold climate zone, stands out as one of China’s regions most susceptible to the repercussions of climate change. To ensure the city’s continued sustainable growth, a thorough assessment of habitat quality must be conducted. This study employs a comprehensive approach integrating the InVEST model, the PLUS model, a landscape pattern analysis, geographic detector, and a geographically weighted regression model. The goal is to assess how land use and habitat quality have changed in Harbin City, investigate factors contributing to spatial heterogeneity in habitat quality, thoroughly examine evolutionary patterns under the inertial development scenario from 2030 to 2050, and propose spatial optimization strategies. There are four key findings. First, from 2000 to 2020, agricultural land and forest were Harbin City’s two most prevalent land use types. The most notable transition occurred from forest to grassland, and the expansion of construction land primarily resulted from its encroachment into agricultural areas. Second, within the area of study, the landscape heterogeneity increased while simultaneously experiencing a decrease in connectivity, and the landscape had a tendency toward a more fragmented spatial distribution. Third, overall habitat quality rose between 2000 and 2020 but declined between 2030 and 2050. There was a “weak in the west and high in the east” distribution pattern in the spatial heterogeneity of habitat quality. Fourth, population density has the most impact on habitat quality, with the NDVI and GDP close behind. Conversely, precipitation and slope had comparatively smaller influences on habitat quality. Natural factors combined had a primarily favorable influence on habitat quality across the research region in terms of spatial distribution. Conversely, population density had a discernibly detrimental impact. Given these findings, this study suggests targeted strategies to optimize habitat quality. These recommendations are relevant not only for biodiversity conservation but also for the development of an ecologically sustainable community, particularly in a cold climate region.
Mapping Tools for Flood Risk Rescue and Assistance Management
Authors: Sortino Barrionuevo Juan Francisco , Castro Noblejas Hugo , Mérida Rodríguez Matías Francisco
Published: January 2024

The assessment of vulnerability to the danger of flooding, with a focus on the need for rescue and assistance from the population, is still in an exploratory scientific phase. The main objective of this research is to propose a methodology based on the issues of rescue and assistance in the face of the risk of floods and to provide a tool for its management. A series of maps is presented, indicating those territorial elements that require rescue and surveillance in a prioritized manner in a visual and accessible way for public administration. Four methodological cartographic proposals have been designed as follows: (1) a map of territory sectors with special rescue needs (dependent population and/or buildings without shelter); a map of the impact on transportation infrastructure and vulnerable areas of buildings (2); a map of vulnerability to possible disorder and looting caused by flooding events (3); and a map of the increase in the cost of deployment for rescue and assistance systems (4). As an experimental zone to test the effectiveness of these proposals, a peri-urban area of the municipality of Málaga (Spain) is chosen, which has an extensive history of severe floods. The results confirm the applied and preventive nature of the tool, which can be incorporated into flood risk management plans and local flood risk action plans developed by public administrations. The main finding of the research is the technical advancement that comes with a precise understanding of vulnerability and its resulting issues for better flood risk management.
The Impacts of Climate Change on Tourism Operators, Trail Experience and Land Use Management in British Columbia’s Backcountry
Authors: Mason Courtney W. , Neumann Pate
Published: January 2024

Climate change, natural resource industries, and an expanding outdoor tourism sector have recently increased access to sensitive backcountry environments in Western Canada. Trail managers are struggling to manage trail conditions with the mounting effects of smoke, dust, fire, flood, area closures, and beetle outbreaks in their regions. Outdoor recreation trail managers are linking these events and are thinking critically about the history and interconnectedness of land use management decisions in the province of British Columbia (BC). As the effects of climate change continue to challenge both trail managers and sport recreationists, guides and trail associations have been identified as key education facilitators in the development and dissemination of environmental consciousness. Guided by a community-based participatory research approach, this study used personal interviews with trail managers across the province to highlight how a connection with local ecosystems can develop a more robust land ethic for recreational trail user communities in BC.
Forest Tales? Unravelling Divergent Land Use and Land Cover Change (LULCC) Maps and State Narratives in Vietnam’s Northern Uplands
Authors: Nguyen Thinh An , Le Hung , Slack Patrick , Kalacska Margaret , Turner Sarah
Published: January 2024

The Vietnamese state has advocated for the sedentarization and market integration of upland northern farmers over the past thirty years, leading to both agrarian and forest transitions. This article presents a comprehensive land use and land cover change (LULCC) analysis of two adjacent upland borderland districts, Phong Thổ and Bát Xát, in northern Vietnam, spanning two neighboring inland provinces, Lai Châu and Lào Cai. These districts are primarily home to ethnic minority farmers who are encouraged by Vietnamese state officials to not only protect forests but to also transition toward cash crop cultivation from less intensive semi-subsistence agriculture. Our LULCC maps, covering the period from 1990 to 2020, revealed a reduction in the speed by which closed-canopy forests were disappearing. During interviews, state officials were confident that this was due to a range of state policies and state-sponsored initiatives, including the promotion of tree crops and payments for forest environmental services. Our own fieldwork in the region suggests other factors are also supporting this decline in deforestation rates, rooted in ethnic minority farmer livelihood decision making. Some state officials were also able to point to factors hindering a more positive result regarding forest cover, including population pressure and new infrastructure. Interestingly, despite our positive findings on Land use and land cover change (LULCC) related to forest cover, one-third of state officials, upon reviewing our LULCC maps, firmly maintained that errors had occurred. Some even proposed that there was an actual rise in forest cover. Our study shows that these discrepancies raise compelling questions about officials’ political motivations and ongoing pressures to uphold the central state’s reforestation and agrarian transition discourses.
Eco-Efficiency of Olive Farms across Diversified Ecological Farming Approaches
Authors: Sintori Alexandra , Gouta Penelope , Konstantidelli Vasilia , Tzouramani Irene
Published: January 2024

Eco-efficiency is commonly used as an indicator of sustainability since it expresses the efficiency with which natural resources are utilized to meet people’s needs. Agriculture relies heavily on these ecological resources and by-produces significant environmental burdens, shifting the interest of researchers and policymakers toward the promotion of ecological practices. However, limited evidence exists regarding eco-efficiency across various ecological approaches like low input, conservation, and organic farming. This paper contributes to the existing literature and provides insight into the eco-efficiency of Cretan olive farms managed under different ecological approaches. Olive oil production is vital for the socio-economic sustainability of Mediterranean agriculture, a significant element of the region’s culture, and the basis of the well-known “Mediterranean diet”; therefore, it is crucial to investigate eco-efficient management options for olive farmers. Data Envelopment Analysis (DEA) and a second-stage statistical analysis are employed to estimate the eco-efficiency of olive farms and investigate factors affecting it. Composite indicators for biodiversity, soil, and input management are incorporated in the eco-efficiency model. The results indicate that organic farms achieve the highest eco-efficiency scores, followed by other ecological approaches. Additionally, eco-efficiency seems to be explained by farmers’ dependency on subsidies, commitment to farming activity, and environmental awareness.
Research on the Spatial Disparities and Convergence of Guangdong’s Urban Economy Based on Industrial Agglomeration and Industrial Proximity
Authors: Huang Xiaojin , Guo Renzhong , Wang Weixi , Li Xiaoming , Fan Yong
Published: January 2024

Understanding the spatial differences and evolutionary characteristics of urban economy and exploring the impact of industrial agglomeration and industrial proximity on urban economic convergence are the bases for scientifically formulating policies for coordinated regional economic development. This study used QGIS 3.10.10 software and the Theil index to analyze the spatial distribution characteristics and regional disparities of urban economy. Then, a spatial econometric model was constructed to analyze the convergence and influencing factors of Guangdong’s urban economy. The results indicate that from 2006 to 2020, Guangdong’s urban economy grew rapidly and the degree of economic agglomeration gradually weakened, but its economic pattern always maintained the “Core-Edge” structural feature. The interval disparities between the Pearl River Delta Urban Agglomeration (PRD) and the edge area have always been greater than the intra-regional disparities, so they are main source of disparities in Guangdong. In Guangdong’s urban economy, σ-convergence and β-convergence coexist. The conditional β-convergence rate is 0.96~1.53%, and the half-life cycle is 45.4~72.36 years. Compared to the PRD, the economic disparities in the edge area are smaller but the convergence speed is faster and the half-life cycle is shorter. Both industrial agglomeration and industrial proximity have a significant impact on the economic convergence of Guangdong’s cities. Among them, industrial agglomeration has a positive impact, while industrial proximity has a negative impact. There is spatial heterogeneity in the impact of industries on economic development. Industrial agglomeration has a positive impact on the overall economic development of Guangdong, but it is not significant within the regions. Industrial proximity has significant negative externalities in the PRD region, and its impact is not significant in the edge area.
Exaptation in Transitional Urban Morphologies: First Notes on the Dynamics of Urban Form Read through the Theories of Natural Evolution
Authors: Trisciuoglio Marco
Published: January 2024

Studying the dynamics of urban form means questioning the processes of evolution of the form in general. The current discussion on the architecture of buildings and urban spaces has drawn the concept of adaptation from theories of natural evolution. These notes propose a reflection on the opposite and controverse concept of exaptation as it was proposed by the biologist and paleontologist Stephen Jay Gould in 1982. Through some examples (the different transformations of some Roman amphitheaters of the imperial age and the metamorphoses that occurred in the 20th century to some Chinese urban fabrics, originally made by courtyard houses), it is possible to extend to urban forms the idea of the casual co-optation for new uses of organs and anatomical parts developed for other reasons. This kind of reflection opens up innovative considerations on the potential of transitional urban analysis and its repercussions on evolutive urban transformation processes.
Improving Tumor-Infiltrating Lymphocytes Score Prediction in Breast Cancer with Self-Supervised Learning
Authors: Kim Sijin , Rakib Hasan Kazi , Ando Yu , Ko Seokhwan , Lee Donghyeon , Park Nora Jee-Young , Cho Junghwan
Published: January 2024

Tumor microenvironment (TME) plays a pivotal role in immuno-oncology, which investigates the intricate interactions between tumors and the human immune system. Specifically, tumor-infiltrating lymphocytes (TILs) are crucial biomarkers for evaluating the prognosis of breast cancer patients and have the potential to refine immunotherapy precision and accurately identify tumor cells in specific cancer types. In this study, we conducted tissue segmentation and lymphocyte detection tasks to predict TIL scores by employing self-supervised learning (SSL) model-based approaches capable of addressing limited labeling data issues. Our experiments showed a 1.9% improvement in tissue segmentation and a 2% improvement in lymphocyte detection over the ImageNet pre-training model. Using these SSL-based models, we achieved a TIL score of 0.718 with a 4.4% improvement. In particular, when trained with only 10% of the entire dataset, the SwAV pre-trained model exhibited a superior performance over other models. Our work highlights improved tissue segmentation and lymphocyte detection using the SSL model with less labeled data for TIL score prediction.
An Insight into Kounis Syndrome: Bridging Clinical Knowledge with Forensic Perspectives
Authors: Forzese Elena , Pitrone Claudia , Cianci Vincenzo , Sapienza Daniela , Ieni Antonio , Tornese Lorenzo , Cianci Alessio , Gualniera Patrizia , Asmundo Alessio , Mondello Cristina
Published: January 2024

Kounis syndrome (KS) is an acute coronary syndrome triggered by allergic or hypersensitivity reactions. Incidence rates vary, with studies reporting 19.4 per 100.000 among all admissions and 3.4% among allergy patients. This review explores the expanding understanding of KS, encompassing various manifestations, and focusing on both clinical data and forensic findings useful in performing a diagnosis. The pathophysiology of this syndrome involves a complex interplay between allergic reactions and the cardiovascular system. Mast cell activation, histamine release, leukotrienes, cytokines, and platelet activation can contribute to coronary events. Three types of classification systems (allergic angina, allergic myocardial infarction, allergic stent thrombosis) aid in categorizing presentations. The diagnosis of KS relies on clinical presentation, laboratory findings, and imaging. Postmortem assessment of KS is based on the integration of circumstantial data, autopsy, and histological findings. Biochemical and immunohistochemical analyses also contribute to postmortem diagnosis. In conclusion, a combined, multidisciplinary approach should be used to ease the diagnostic process, which is crucial for forensic practitioners in confirming KS occurrence.
Treatment Patterns for and Characteristics of Headache in Children and Adolescents Aged 6–17 Years in Japan: A Retrospective Cross-Sectional and Longitudinal Analysis of Health Insurance Claims Data
Authors: Katsuki Masahito , Matsumori Yasuhiko , Ichihara Taisuke , Yamada Yuya , Kawamura Shin , Kashiwagi Kenta , Koh Akihito , Goto Tetsuya , Kaneko Kazuma , Wada Naomichi , Yamagishi Fuminori
Published: January 2024

Objective: To investigate the prescription patterns for patients aged 6–17 years with headaches in the REZULT database. Methods: We cross-sectionally investigated (Study 1) the pattern of prescription and the proportion of triptan overprescription (≥30 tablets/90 d of triptans) among patients diagnosed with headaches in 2020. Next, we longitudinally studied patients (Study 2) for more than two years from the initial headache diagnosis (July 2010 to April 2022). The number of prescribed tablets was counted every 90 days. Results: In Study 1, headache diagnoses were assigned to 62,568 of 543,628 (11.51%) patients, and 1524 of 62,568 (2.44%) patients received acute medication. Single nonsteroidal anti-inflammatory drugs and triptans were prescribed to 620/624 (99.36%) and 5/624 (0.80%) of patients aged 6–11 years, respectively, and 827/900 (91.89%) and 91/900 (10.11%) of patients aged 12–17 years, respectively. Triptan overprescription was observed in 11/96 (11.46%) patients, and 5/11 (45.45%) of those patients received prophylactic medication. In Study 2, 80,756/845,470 (9.55%) patients aged 6–17 years were diagnosed with headaches that persisted for at least two years. Over two years, 44/80,756 (0.05%) patients were overprescribed triptans, and 3408/80,756 (4.22%) patients were prescribed prophylaxis on at least one occasion. Conclusions: Based on real-world data, the appropriate use of prophylactic treatment is still problematic. Overprescription of triptans was observed, although the number of patients was small.
Characterization, Bioactivity, and Biodistribution of 35 kDa Hyaluronan Fragment
Authors: Gantumur Munkh-Amgalan , Jia Xiaoxiao , Hui Jessica H. , Barber Christy , Wan Li , Furenlid Lars R. , Martin Diego R. , Hui Mizhou , Liu Zhonglin
Published: January 2024

It has been reported that hyaluronic acid (HA) with a 35 kDa molecular weight (HA35) acts biologically to protect tissue from injury, but its biological properties are not yet fully characterized. This study aimed to evaluate the cellular effects and biodistribution of HA35 compared to HA with a 1600 kDa molecular weight (HA1600). We assessed the effects of HA35 and HA1600 on cell migration, NO and ROS generation, and gene expression in cultured macrophages, microglia, and lymphocytes. HA35 was separately radiolabeled with 99mTc and 125I and administered to C57BL/6J mice for in vivo biodistribution imaging. In vitro studies indicated that HA35 and HA1600 similarly enhanced cell migration through HA receptor binding mechanisms, reduced the generation of NO and ROS, and upregulated gene expression profiles related to cell signaling pathways in immune cells. HA35 showed a more pronounced effect in regulating a broader range of genes in macrophages and microglia than HA1600. Upon intradermal or intravenous administration, radiolabeled HA35 rapidly accumulated in the liver, spleen, and lymph nodes. In conclusion, HA35 not only exhibits effects on cellular bioactivity comparable to those of HA1600 but also exerts biological effects on a broader range of immune cell gene expression. The findings herein offer valuable insights for further research into the therapeutic potential of HA35 in inflammation-mediated tissue injury.
Mechanisms of Epigenetic Inheritance in Post-Traumatic Stress Disorder
Authors: Chou Pei-Chen , Huang Yu-Chi , Yu Sebastian
Published: January 2024

Post-traumatic stress disorder (PTSD) is a psychiatric disorder that causes debilitating functional impairment in patients. Observations from survivors of traumatic historical events solidify that this disease is not only associated with personal experiences but can also be inherited from familial traumas. Over the past decades, researchers have focused on epigenetic inheritance to understand how responses to adverse experiences can be passed down to future generations. This review aims to present recent findings on epigenetic markers related to PTSD and research in the intergenerational inheritance of trauma. By understanding the information, we hope that epigenetic markers can act as biochemical measurements for future clinical practice.
Power Loss Analysis of an Oil-Jet Lubricated Angular Contact Ball Bearing: Theoretical and Experimental Investigations
Authors: Darul Lionel , Touret Thomas , Changenet Christophe , Ville Fabrice
Published: January 2024

This study presents a theoretical and experimental analysis to quantify the power losses generated by an oil jet lubricated angular contact ball bearing. The analysis is conducted for a moderate speed range (N∙dm product less than 106) and a limited applied load (<5% of the static capacity). The lubrication regime of each ball is studied through a theoretical model and varies from Iso-Viscous Rigid to Elasto-Hydrodynamic. Therefore, the hydrodynamic effects are considered in the power loss calculation. An experimental campaign is carried out and the influence of several parameters (applied load, oil injection temperature, speed, etc.) is studied. A good agreement is found between the developed model and the measurements. It is shown that the radial applied load has no influence on power losses, unlike speed and axial load. This can be explained by the load distribution and the hydrodynamic rolling contribution on the low loaded balls.
Multi-Field Coupling Numerical Analysis and Experimental Validation of Surface-Textured Metal Seals in Roller Cone Bits
Authors: Ma Yi , Li Ziang , Yuan Ziyang , Meng Xiangkai , Peng Xudong , Jiang Jinbo
Published: January 2024

Metal seals play a crucial role in ensuring the dependable functioning of the bearing system in roller cone bits. Due to the intricate nature of downhole conditions, the microstructure design of sealing end faces, specifically the surface texture, is rarely used in metal seals. This study focuses on examining the applicability of surface texture technology in metal seals for cone bits to enhance the lubrication characteristics and friction and wear properties of liquid film between end faces. A multi-field coupling model of surface-textured metal seals was established and experimentally verified. The liquid film carrying the capacity and sealing performance of five different shapes of surface-textured end faces (circle, ellipse I (horizontal), ellipse II (vertical), triangle, and chevron) were investigated under varying rotational speeds and environmental pressures. The influences of texture parameters, including depth and area ratio, on the lubrication characteristics and friction reduction effects of surface-textured metal seals were investigated, and the microscopic wear morphology characteristics of the sealing end faces were analyzed. The results show that surface textures can effectively improve the liquid film state and comprehensive performance of metal seals. Specifically, triangle textures significantly enhance the hydrodynamic pressure effect and weaken the abrasive wear and adhesive wear of the end faces. However, when the environmental pressure is p ≥ 30 MPa, the surface textures gradually lose the advantages of dynamic lubrication but can still reduce friction. The proper texture depth and area ratio can achieve zero leakage (obtained theoretically) and minimal friction in metal seals.
Analysis of Water-Lubricated Journal Bearings Assisted by a Small Quantity of Secondary Lubricating Medium with Navier–Stokes Equation and VOF Model
Authors: Zhang Xiaohan , Yu Tao , Ji Hao , Guo Feng , Duan Wenbin , Liang Peng , Ma Ling
Published: January 2024

Due to the low viscosity of water, water-lubricated bearings are susceptible to significant wear and noise in demanding operating conditions. It has been demonstrated that a small quantity of secondary lubricating medium can improve the lubrication performance of water-lubricated contact surfaces and achieve the purpose of temporary risk aversion. As a further step, the feasibility of the proposed idea is experimentally validated on a water-lubricated bearing test bench. A numerical model that couples the N–S equation and the VOF model is then developed to investigate the behavior of the flow field lubricated by pure water and water with a small quantity of the secondary lubricating medium. This model provides the predictions of important quantities such as the load-carrying capacity, the secondary lubricating medium volume fraction and the contact pressure under different lubricated conditions. The results show that the secondary lubricating medium can enter into the contact region and improve the lubrication performance of water-lubricated bearings, especially at lower shaft rotational speeds. Therefore, the feasibility of our proposed idea is verified, which provides a promising approach to reduce the wear and friction of water-lubricated bearings when they encounter short-time severe working conditions.
Development of Thermodynamic Criteria for Determining the Composition of Duplex Stainless Steels with High Corrosion Resistance
Authors: Fedorov Aleksandr , Karasev Vladimir , Kovalev Pavel , Shaposhnikov Nikita , Zhitenev Andrey
Published: January 2024

One of the most popular methods for ranking duplex stainless steels (DSSs) and predicting their corrosion properties is the calculation of the pitting resistance equivalent number (PREN). However, since DSSs are two-phase materials with a significant fraction of secondary phases and precipitates, the application of the PREN can be highly limited. This article attempted to use a new approach to describe the corrosion resistance of these steels. The corrosion resistance of two DSSs of the same class was investigated. Under identical solution heat treatments in the temperature range of 1050–1200 °C, the crevice corrosion resistance of one steel increased, while that of the other decreased. It was demonstrated that the amounts of austenite and ferrite changed similarly in these steels, and the different corrosion resistances were associated with the behaviors of secondary phases: niobium carbonitride and chromium nitride. SEM-EDS analysis was conducted to analyze the redistribution of elements between phases in both cases, showing good agreement with the thermodynamic modeling results. The PREN was calculated for each phase depending on the treatment temperature, and a method for calculating the effective PREN (PRENeff), accounting for phase balance and secondary phases, was proposed. It was shown that this indicator described corrosion properties better than the classical PREN calculated for the average steel composition. This study demonstrated how the calculation of critical temperatures (the temperature of equal amounts of ferrite and austenite, the temperature of the beginning of chromium nitride formation, and the temperature of the beginning of σ-phase formation) could describe the corrosion resistance of DSSs. Maximum possible deviations from these temperatures were defined, allowing the attainment of the required corrosion properties for the steels. Based on the conducted research, an approach for selecting new compositions of DSSs was proposed.
Evaluation of the Surface Topography and Deformation of Vertical Thin-Wall Milled Samples from the Nickel Alloy Inconel 625
Authors: Kurpiel Szymon , Zagórski Krzysztof , Cieślik Jacek , Skrzypkowski Krzysztof , Tuleshov Amandyk
Published: January 2024

During the production of components, manufacturers of structures are obliged to meet certain requirements and ensure appropriate quality characteristics. It is especially important during the manufacturing of thin-walled structures, which are subject to many errors during machining due to the reduced rigidity of the products, including the deformation of thin walls, which may be the result of the vibration of the system. The appearance of vibrations reduces the quality of the machined surface affecting the increase in the values of surface topography parameters—waviness and roughness. Thin-wall structures—titanium or nickel alloy, among others—play a key role in the aerospace industry, which constantly strives to reduce the weight of the entire structure while meeting requirements. The present work focuses on the evaluation of the parameters of surface topography, dimensional and shape accuracy during the milling of nickel alloy Inconel 625 samples containing a thin wall in a vertical orientation. The experiment was conducted under controlled cutting conditions using a constant material removal rate. As part of the surface topography section, the distribution of waviness, Wa and Wz, and roughness, Ra and Rz, was determined in selected measurement areas in the direction parallel to the direction of the feed motion. Dimensional deviations, measured with a 3D optical scanner, were determined in selected cross sections in the direction perpendicular and parallel to the bottom of the sample presenting the deflection of the thin-walled structure. The results provide information that the used parameter sets affect the measured quantities to varying degrees.
Chemical Modification of Dental Dimethacrylate Copolymer with Tetramethylxylylene Diisocyanate-Based Quaternary Ammonium Urethane-Dimethacrylates—Physicochemical, Mechanical, and Antibacterial Properties
Authors: Drejka Patryk , Chrószcz-Porębska Marta , Kazek-Kęsik Alicja , Chladek Grzegorz , Barszczewska-Rybarek Izabela
Published: January 2024

In this study, two novel quaternary ammonium urethane-dimethacrylates (QAUDMAs) were designed for potential use as comonomers in antibacterial dental composite restorative materials. QAUDMAs were synthesized via the reaction of 1,3-bis(1-isocyanato-1-methylethyl)benzene with 2-(methacryloyloxy)ethyl-2-decylhydroxyethylmethylammonium bromide (QA10+TMXDI) and 2-(methacryloyloxy)ethyl-2-dodecylhydroxyethylmethylammonium bromide (QA12+TMXDI). Their compositions with common dental dimethacrylates comprising QAUDMA 20 wt.%, urethane-dimethacrylate monomer (UDMA) 20 wt.%, bisphenol A glycerolate dimethacrylate (Bis-GMA) 40 wt.%, and triethylene glycol dimethacrylate (TEGDMA) 20 wt.%, were photocured. The achieved copolymers were characterized for their physicochemical and mechanical properties, including their degree of conversion (DC), glass transition temperature (Tg), polymerization shrinkage (S), water contact angle (WCA), flexural modulus (E), flexural strength (FS), hardness (HB), water sorption (WS), and water leachability (WL). The antibacterial activity of the copolymers was characterized by the minimum bactericidal concentration (MBC) and minimum inhibitory concentration (MIC) against Staphylococcus aureus and Escherichia coli. The achieved results were compared to the properties of a typical dental copolymer comprising UDMA 40 wt.%, Bis-GMA 40 wt.%, and TEGDMA 20 wt.%. The introduction of QAUDMAs did not deteriorate physicochemical and mechanical properties. The WS and WL increased; however, they were still satisfactory. The copolymer comprising QA10+TMXDI showed a higher antibacterial effect than that comprising QA12+TMXDI and that of the reference copolymer.
Thermodynamic Guidelines for the Mechanosynthesis or Solid-State Synthesis of MnFe2O4 at Relatively Low Temperatures
Authors: Antunes Isabel , Baptista Miguel , Kovalevsky Andrei , Yaremchenko Aleksey , Frade Jorge
Published: January 2024

Herein, thermodynamic assessment is proposed to screen suitable precursors for the solid-state synthesis of manganese ferrite, by mechanosynthesis at room temperature or by subsequent calcination at relatively low temperatures, and the main findings are validated by experimental results for the representative precursor mixtures MnO + FeO3, MnO2 + Fe2O3, and MnO2 +2FeCO3. Thermodynamic guidelines are provided for the synthesis of manganese ferrite from (i) oxide and/or metallic precursors; (ii) carbonate + carbonate or carbonate + oxide powder mixtures; (iii) other precursors. It is also shown that synthesis from metallic precursors (Mn + 2Fe) requires a controlled oxygen supply in limited redox conditions, which is hardly achieved by reducing gases H2/H2O or CO/CO2. Oxide mixtures with an overall oxygen balance, such as MnO + Fe2O3, act as self-redox buffers and offer prospects for mechanosynthesis for a sufficient time (>9 h) at room temperature. On the contrary, the fully oxidised oxide mixture MnO2 + Fe2O3 requires partial reduction, which prevents synthesis at room temperature and requires subsequent calcination at temperatures above 1100 °C in air or in nominally inert atmospheres above 750 °C. Oxide + carbonate mixtures, such as MnO2 +2FeCO3, also yield suitable oxygen balance by the decomposition of the carbonate precursor and offer prospects for mechanosynthesis at room temperature, and residual fractions of reactants could be converted by firing at relatively low temperatures (≥650 °C).
Fatigue and Impact Properties of Kenaf/Glass-Reinforced Hybrid Pultruded Composites for Structural Applications
Authors: Balakrishnan Thinesh Sharma , Sultan Mohamed Thariq Hameed , Shahar Farah Syazwani , Basri Adi Azriff , Shah Ain Umaira Md , Sebaey Tamer Ali , Łukaszewicz Andrzej , Józwik Jerzy , Grzejda Rafał
Published: January 2024

To address the weight, cost, and sustainability associated with fibreglass application in structural composites, plant fibres serve as an alternative to reduce and replace the usage of glass fibres. However, there remains a gap in the comprehensive research on plant fibre composites, particularly in their durability for viable structural applications. This research investigates the fatigue and impact properties of pultruded kenaf/glass-reinforced hybrid polyester composites tailored for structural applications. Utilising kenaf fibres in mat form, unidirectional E-glass fibre direct roving yarns, and unsaturated polyester resin as key constituents, pultruded kenaf/glass hybrid profiles were fabricated. The study reveals that pultruded WK/UG alternate specimens exhibit commendable fatigue properties (18,630 cycles at 60% ultimate tensile strength, UTS) and fracture energy (261.3 kJ/m2), showcasing promise for moderate load structural applications. Notably, the pultruded 3 WK/UG/3WK variant emerges as a viable contender for low-load structural tasks recorded satisfactory fatigue properties (10,730 cycles at 60% UTS) and fracture energy (167.09 kJ/m2). Fatigue failure modes indicate that the stress applied is evenly distributed. Ductile failures and delaminations during impact test can be attributed to damping and energy absorbing properties of kenaf fibres. Moreover, incorporating kenaf as a hybrid alternative demonstrates substantial reductions in cost (35.7–50%) and weight (9.6–19.1%). This research establishes a foundation for advancing sustainable and efficient structural materials and highlights the significant role of materials design in shaping the future of engineering applications.
Evaluation of Compressive and Bending Strength of a Geopolymer Based on Lateritic Clays as an Alternative Hydraulic Binder
Authors: Ochoa Walter , Málaga Moisés , Tapia Arturo , Calabokis Oriana , Nuñez de la Rosa Yamid , Viscarra Chirinos Gunther , Pinto Lavayén Sebastián
Published: January 2024

In Bolivia, lateritic soils are common in humid tropical regions and can be used in the construction industry as an alternative to materials that cause a negative environmental impact, such as cement. The production of Portland cement causes environmental issues like significant greenhouse gas emissions and air pollution. To address this problem, geopolymers have been introduced as an alternative binder with low CO2 emissions. In this regard, geopolymers based on lateritic clays have been studied mineralogically, chemically, and on their compressive strength separately. However, there are still no studies on lateritic clays present in Bolivia and their mechanical, mineralogical, and chemical properties combined in a geopolymer. Therefore, this present research proposes the evaluation of a geopolymer made from laterite clays. Compression and flexural tests were carried out, along with mineralogical and chemical analyses on mortar and geopolymer cubes and prisms. The results indicate that the laterite clay-based geopolymer has lower compressive strength compared to Portland cement IP (cement type I with the addition of pozzolana) mortar. However, the flexural strength tests show a slight increase in the case of the geopolymer.
The Adsorption of Pb(II) from Aqueous Solution Using KOH-Modified Banana Peel Hydrothermal Carbon: Adsorption Properties and Mechanistic Studies
Authors: Bai Tao , Zhao Jiaxin , Tian Laixin , Zhang Luming , Jin Zhiping
Published: January 2024

Adopting banana peel as a raw material, the adsorption properties of banana peel hydrothermal carbon modified with a KOH solution for lead ions in aqueous solution were studied. The surface structure and functional groups of the modified hydrothermal carbon were analyzed by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier-transform infrared (FT-IR) spectroscopy, the Brunner–Emmet–Teller (BET) method, element analysis, and Raman spectroscopy. The results showed that an adsorption capacity of 42.92 mg/g and a removal rate of 86.84% were achieved when the banana peel hydrothermal carbon was modified with a KOH solution of 0.5 mol/L, with a pH of 6 and a solid–liquid ratio of 1 g/L. The equilibrium adsorption time for lead ions in solution being adsorbed using KOH-modified hydrothermal carbon was 240 min, the adsorption process satisfied the quasi-second-order kinetic model and the Redlich–Peterson isotherm equation, and the equilibrium removal efficiency was 88.62%. The adsorption of lead ions using KOH-modified hydrothermal carbon is mainly chemical–physical adsorption.
In Vitro Handling Characteristics of a Particulate Bone Substitute for Ridge Preservation Procedures
Authors: Dahl Samira , Klär-Quarz Virgilia , Schulz Annika , Karl Matthias , Grobecker-Karl Tanja
Published: January 2024

While particulate bone substitute materials are applied in a variety of augmentation procedures, standardized defects are being used for preclinical testing. This in vitro study evaluated the density and homogeneity of a particulate bone substitute in ridge preservation procedures. Premolars and molars were extracted in ten semimandibles of minipig cadavers. Light body impression material was used for determining the volume of the extraction sites followed by augmentation with particulate material, thereby weighing the graft material needed. Microradiographs and histologic sections were obtained for evaluating the homogeneity and density of the augmentation material. Statistical analyses were based on Shapiro–Wilk tests, Spearman’s rho and one sample Wilcoxon test followed by Bonferroni–Holm correction for multiple testing (α = 0.05). Based on 103 single alveoli evaluated, the mean volume determined was 0.120 cm3 requiring a mean amount of graft material of 0.155 g. With only three exceptions, all parameters (volume, mass of augmentation material, density and homogeneity) correlated significantly (p < 0.020). The apical parts of the alveoli showed reduced density as compared to the middle parts (p < 0.001) and the homogeneity of the augmentation material was also lower as compared to the middle (p < 0.001) and cervical parts (p </= 0.040). The packing of augmentation material is critical when non-standardized defects are treated.
Photo- and X-ray Induced Cytotoxicity of CeF3-YF3-TbF3 Nanoparticle-Polyvinylpyrrolidone—“Radachlorin” Composites for Combined Photodynamic Therapy
Authors: Khusainova Alina I. , Nizamutdinov Alexey S. , Shamsutdinov Nail I. , Kalinichenko Svetlana , Safin Damir I. , Gafurov Marat , Lukinova Elena V. , Batygov Sergey Kh. , Kuznetsov Sergey V. , Zinchenko Sergey V. , Zelenikhin Pavel V. , Pudovkin Maksim
Published: January 2024

The Ce0.5Y0.35Tb0.15F3 nanoparticles with a CeF3 hexagonal structure were synthesized using the co-precipitation technique. The average nanoparticle diameter was 14 ± 1 nm. The luminescence decay curves of the Ce0.5Y0.35Tb0.15F3 nanoparticles (λem = 541 nm, 5D4–7F5 transition of Tb3+) conjugated with Radachlorin using polyvinylpyrrolidone coating as well as without Radachlorin were detected. Efficient nonradiative energy transfer from Tb3+ to the Radachlorin was demonstrated. The maximum energy transfer coefficients for the nanoparticles conjugated with Radachlorin via polyvinylpyrrolidone and without the coating were 82% and 55%, respectively. The average distance between the nanoparticle surface and Radachlorin was R0 = 4.5 nm. The best results for X-ray-induced cytotoxicity were observed for the NP-PVP-Rch sample at the lowest Rch concentration. In particular, after X-ray irradiation, the survival of A549 human lung carcinoma cells decreased by ~12%.
A Novel Customised Load Adaptive Framework for Induction Motor Fault Classification Utilising MFPT Bearing Dataset
Authors: Hejazi Shahd Ziad , Packianather Michael , Liu Ying
Published: January 2024

This research presents a novel Customised Load Adaptive Framework (CLAF) for fault classification in Induction Motors (IMs), utilising the Machinery Fault Prevention Technology (MFPT) bearing dataset. CLAF represents a pioneering approach that extends traditional fault classification methodologies by accounting for load variations and dataset customisation. Through a meticulous two-phase process, it unveils load-dependent fault subclasses that have not been readily identified in traditional approaches. Additionally, new classes are created to accommodate the dataset’s unique characteristics. Phase 1 involves exploring load-dependent patterns in time and frequency domain features using one-way Analysis of Variance (ANOVA) ranking and validation via bagged tree classifiers. In Phase 2, CLAF is applied to identify mild, moderate, and severe load-dependent fault subclasses through optimal Continuous Wavelet Transform (CWT) selection through Wavelet Singular Entropy (WSE) and CWT energy analysis. The results are compelling, with a 96.3% classification accuracy achieved when employing a Wide Neural Network to classify proposed load-dependent fault subclasses. This underscores the practical value of CLAF in enhancing fault diagnosis in IMs and its future potential in advancing IM condition monitoring.