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Article

20 January 2025

Visible Monuments above and below Ground Level, a Time-Honored Site from the Late Bronze Age to Modern Times

Due to the complex geometry of the monuments, it is often necessary to adapt the image collection process for their mapping. For the optimal mapping of the stronghold of Lazaritsa Chorygi (Greece) and its slopes, vertical, inclined, and horizontal images from different heights were collected using an Unmanned Aircraft System. Thus, for a monument of special archaeological/historical interest and natural beauty, a large set of high-spatial resolution data and final products (digital surface model and orthophotomosaic with spatial resolution 5.6 cm and 2.8 cm, respectively) is available. In addition, in the wider area of the fortified site, military structures (fire trenches, communication trenches, shelters, front and support trenches, and strong points) of the Great War length of 9 km were identified and mapped, which were identified in the 2003 or 2004 Google Earth Pro images, but worryingly are almost absent from the contemporary Google Earth Pro images.

Keywords: Unmanned Aerial System; Stronghold; Military structures; Complex geometry; Collecting images; Digital surface model; Orthophoto mosaic; Spatial resolution

Review

16 January 2025

Biological Bone and Replacement Materials in Grinding: Force Model and Processing Capability

Grinding is widely used in orthopedic surgery to remove bone tissue material, but due to the complex and brittle structure of bone, it is prone to mechanical stresses that cause cracks and damage to the bone tissue. Furthermore, bone replacement materials typically have high hardness, strength, and brittleness, which lead to increased tool wear and damage, such as cracks and deformation during grinding. Therefore, ensuring the surface quality of bone and replacement materials during the grinding process has become a critical issue. This necessitates the development of grinding force models that consider various processing parameters, such as feed rate and cutting depth, to guide industrial production. However, currently, research on the grinding force prediction models for bone tissue and its replacement materials is relatively scarce, and there is a lack of corresponding grinding force model reviews for unified guidance. Based on this, this article focuses on bone grinding technology and, conducts a critical comparative analysis of the grinding force models for bone tissue and its replacement materials, and then summarizes the grinding force prediction models in the grinding process of bone tissue and bone replacement materials. First, according to the material types and material removal mechanisms, the materials are categorized into bone tissue, bio-inert ceramics, and bio-alloys, and the material removal process during grinding is analyzed. Subsequently, the grinding force prediction models for each material and the accuracy errors of each model are summarized. The paper also reviews the application of these grinding force prediction models, explaining how processing parameters such as feed rate and cutting depth influence grinding forces and their interrelationship. Finally, in light of the current issues in the grinding of bone tissue and replacement materials, potential future research directions are proposed, aiming to provide theoretical guidance and technical support for improving the grinding quality of bone tissue and its replacement materials.

Keywords: Grinding; Bone; Bio-inert ceramics; Bio-alloys; Grinding force

Review

14 January 2025

Artificial Intelligence and Machine Learning for Sustainable Manufacturing: Current Trends and Future Prospects

Artificial Intelligence (AI) and Machine Learning (ML) are transforming manufacturing processes, offering unprecedented opportunities to enhance sustainability and environmental stewardship. This comprehensive review analyzes the transformative impact of AI technologies on sustainable manufacturing, focusing on critical applications, including energy optimization, predictive maintenance, waste reduction, and circular economy implementation. Through systematic analysis of current research and industry practices, the study examines both the opportunities and challenges in deploying AI-driven solutions for sustainable manufacturing. The findings provide strategic insights for researchers, industry practitioners, and policymakers working towards intelligent and sustainable manufacturing systems while elucidating emerging trends and future directions in this rapidly evolving field.

Keywords: Artificial intelligence; Machine learning; Sustainable manufacturing; Circular economy; Industry 4.0; Energy; Waste recycling

Article

14 January 2025

CYLD Regulates T Cell Metabolism and Mitochondrial Autophagy through LKB1/AMPKα Pathway

The deubiquitinating enzyme cylindromatosis (CYLD) plays a fundamental role in regulating T cell development and activation. Previous studies have shown that CYLD is associated with autophagy, while AMP activated protein kinase (AMPK) pathway regulates the development of autophagy and affects cell metabolism. However, the mechanism by which CYLD affects autophagy and whether it affects the downstream metabolism of AMPKα remains unclear. In this study, we used the CYLD gene knockout model in Jurkat cells to investigate the mechanism of CYLD and autophagy and its relationship with cellular metabolism. The results show that CYLD deletion promotes autophagy through AMPKα/mTOR/ULK1 signaling pathway, promotes mitochondrial autophagy to improve mitochondrial function and attenuates cell lipid metabolism in Jurkat cells.

Keywords: CYLD; AMPK; Autophagy; Metabolism; T cells; Mitochondria

Review

14 January 2025

A Review of Phosphorous in Fluvial Floodplains: Source or Sink?

Fluvial floodplains are water-land transitional zones, playing an important role in hydrological and ecological systems. To date, the phosphorus migration and transformation in floodplain sediments remain elusive, which poses a large effect on river nutrient levels and primary productivity. This review summarized the sedimentary characteristics of floodplains and analyzed the spatial differences and temporal variations in phosphorus distribution. We further analyzed their potential change in floodplains under various conditions, determining the sedimentation and mineralization process of phosphorus. Meanwhile, phosphorus in the sediment will experience dynamic fluctuation as a source or sink of fluvial floodplains based on varying factors, including hydrological conditions, climate variations, biological activity, and pedological characteristics. In particular, the productivity and community population in floodplains, like vegetation and fishes, will be primarily associated with the periodic changes in phosphorus through food chain. Lastly, this review provided corresponding perspectives on improving the phosphorus administration in river floodplains based on existing problems. In total, it is anticipated that it will enhance the understanding of phosphorus resources or sink in the fluvial floodplains, contributing to the stability of aquatic ecosystems.

Keywords: Phosphorus; Fluvial floodplains; Release; Ecological effect; Periodic change

Review

13 January 2025

Comparative Analysis of Idiopathic Pulmonary Fibrosis and Progressive Pulmonary Fibrosis: Epidemiology, Pathophysiology, Clinical Features, Diagnosis and Treatment

Idiopathic pulmonary fibrosis (IPF) is a chronic fibrosing interstitial disease of unknown origin, characterized by radiological and histological features consistent with usual interstitial pneumonia (UIP). It is marked by a progressive worsening of dyspnea and a decline in lung function. Both IPF and PPF are comparable because they have poor prognoses with a median survival time from diagnosis of around 2–4 years without antifibrotic therapy. This review shows the main specific characteristics and differences of epidemiology, pathophysiology, clinical and radiological features, treatment, and prognosis of IPF and PPF.

Keywords: Idiopathic pulmonary fibrosis; Progressive pulmonary fibrosis; Fibrosis interstitial pneumonia; Interstitial lung disease

Article

10 January 2025

Investigation of the Performance Characteristics of Unequal Co-Axial Rotors

The behaviour of co-axial rotors is well understood, and they are especially practical for large UAVs due to their increased thrust without changing the vehicle footprint. However, for co-axial systems with varying propeller diameters between the two disks, research is more limited. The goal of this paper was to determine an optimal configuration for several different unequal co-axial setups using numerous different propeller combinations and separation ratios. Propellers with diameters of 26 and 29 inches are tested at separation ratios of 0.05 to 0.35. Thrust and power were collected using an off-the-shelf FS15-TYTO thrust stand, with the upstream and downstream propellers running at equal throttles. From this, performance was assessed through efficiency, thrust, and power consumption, and comparisons were made to an ideal combination without losses. The results show that for unequal combinations, the user should place the smaller propeller upstream for greater efficiency, but for maximum thrust capacity, two equal propellers are preferred. When compared to two independent rotors of the same size, a 26″ upstream rotor and a 29″ downstream rotor minimised thrust loss to 16%, compared to 23% for the opposite arrangement. It was also found that the optimal separation ratio is always approximately 0.2.

Keywords: Unequal; Propellers; Co-axial; Aerodynamics; Efficiency; z/D ratio; Optimisation

Article

09 January 2025

Advanced Materials: Nature of Strongly Correlated Quantum Spin Liquid in Sr3CuNb2O9

Quantum spin liquids of frustrated magnets are among the most attractive and basic systems in physics. Frustrated magnets exhibit exceptional properties as insulators and metals, making them advanced materials that represent materials for future technologies. Therefore, a reliable theory describing these materials is of great importance. The fermion condensation theory provides an analytical description of various frustrated quantum spin liquids capable of describing the thermodynamic and transport properties of magnets based on the idea of spinons, represented by chargeless fermions filling the Fermi sphere up to the Fermi momentum pF . We show that the low temperature thermodynamic of Sr3CuNb2O9 in magnetic fields is defined by strongly correlated quantum spin liquid. Our calculations of its thermodynamic properties agree well with recent experimental facts and allow us to reveal their scaling behavior, which is very similar to that observed both in heavy-fermion metals and in frustrated magnets or insulators. We demonstrate for the first time that Sr3CuNb2O9 belongs to the family of strongly correlated Fermi systems that form a new state of matter.

Keywords: Quantum phase transitions; Flat bands; Quantum spin liquid; Thermodynamic properties; Scaling behavior; Universal properties; Heavy fermion metals

Review

09 January 2025

Recent Advancements in Alumina-Based High-Temperature Insulating Materials: Properties, Applications, and Future Perspectives

As a high-temperature thermal insulation material with excellent mechanical properties, alumina (Al2O3)-based materials hold significant potential for applications in aerospace, advanced manufacturing, automobiles, industrial furnaces, and other fields. However, the inherent brittleness of alumina poses a limitation to its wider application. Therefore, there is a pressing need to develop alumina-based materials that offer high toughness while retaining superior mechanical properties. This paper begins by exploring the structure of alumina, highlighting its thermal conductivity, insulation, and mechanical properties in high-temperature environments. It then reviews the classification and synthesis methods of alumina-based materials, along with the latest advances in design strategies. Notably, the rational design of alumina composition, structure, and morphology is emphasized as crucial for optimizing material performance, thereby supporting the industrial development and application of these materials in high-tech sectors. Finally, the paper discusses the challenges and evolution of alumina-based materials in real-world industrial applications and suggests potential directions for future development.

Keywords: Alumina-based materials; High-temperature; Insulating materials; Synthesis; Aerospace applications; Industrial furnace applications; Environmentally friendly materials

Article

09 January 2025

Sustainability Practices and Financial Performance: Evidence from BIST Electricity Index

Amidst the backdrop of heightened market risks associated with transitioning to a lower-carbon economy, this study pioneers an examination of the correlation between sustainability and financial performance within Turkish energy market generator and retailer companies. In this study, the sustainability performance, exposure to market risks and effects on the financial performance of sub-sectors of companies listed in the BIST Electricity index were analyzed using panel data regression. The findings reveal a nuanced relationship between sustainability factors and financial performance, underscoring the imperative for electricity sector companies to prioritize sustainability initiatives not only for ethical reasons but also as a strategic imperative for long-term financial success and stakeholder value creation. Finally, the possibility of impending regulatory changes underscores the importance of early adoption of sustainability practices to mitigate potential financial liabilities and navigate future market risks effectively.

Keywords: Esg; Esg performance; Sustainability; Corporate financial performance; Panel data regression; Electricity sector
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