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Article

22 July 2024

Aging-Associated Molecular Changes in Human Alveolar Type I Cells

Human alveolar type I (AT1) cells are specialized epithelial cells that line the alveoli in the lungs where gas exchange occurs. The primary function of AT1 cells is not only to facilitate efficient gas exchange between the air and the blood in the lungs, but also to contribute to the structural integrity of the alveoli to maintain lung function and homeostasis. Aging has notable effects on the structure, function, and regenerative capacity of human AT1 cells. However, our understanding of the molecular mechanisms driving these age-related changes in AT1 cells remains limited. Leveraging a recent single-cell transcriptomics dataset we generated on healthy human lungs, we identified a series of significant molecular alterations in AT1 cells from aged lungs. Notably, the aged AT1 cells exhibited increased cellular senescence and chemokine gene expression, alongside diminished epithelial features such as decreases in cell junctions, endocytosis, and pulmonary matrisome gene expression. Gene set analyses also indicated that aged AT1 cells were resistant to apoptosis, a crucial mechanism for turnover and renewal of AT1 cells, thereby ensuring alveolar integrity and function. Further research on these alterations is imperative to fully elucidate the impact on AT1 cells and is indispensable for developing effective therapies to preserve lung function and promote healthy aging.

Keywords: Aging; Alveolar Type I Cell; Senescence; Epithelial Cell Identity; Tight Junction; Apoptosis

Review

19 July 2024

Solid Additives to Increase the Service Life of Ceramic Cutting Tool: Methodology and Mechanism

With the development of the manufacturing industry, there is an increasing demand for high-efficiency processing, high-precision processing, and high-temperature processing. The characteristics of ceramic tools, such as high hardness and wear resistance, make them suitable for high-precision processing. Additionally, their excellent high temperature resistance perfectly meets the requirements of high temperature processing. However, ceramic tools have a relatively low strength and are prone to breakage, which limits their application in some high-strength machining fields. Their low toughness and brittleness also lead to easy cracking and reduced tool life, resulting in frequent tool changes that further limit processing efficiency. Therefore, improving the service life of ceramic tool materials is crucial to enhance processing efficiency and achieve significant economic benefits. With the development of material science, solid additives with toughening and strengthening properties have greatly improved the performance of ceramic tool materials and given ceramic tools new life-enhancing properties, such as lubrication and repair. By utilizing the combined action of one or more solid additives and employing surface coating technology, the service life of ceramic cutting tools is significantly extended. This makes the application of ceramic tools in industrial cutting more and more widely, and the demand is also growing rapidly. However, the mechanism and methods of various solid additives to increase the life of ceramic tool materials have not been systematically reviewed. The analysis of the composition and functional properties of ceramic tool materials was used as a basis to summarize the mechanism by which various solid additives improve the service life of ceramic tool materials, and to provide points for attention in their use. The aim is to assist researchers in designing and preparing new ceramic tool materials that can meet processing requirements. Finally, the research status, challenges, and prospects of enhancing the service life of ceramic cutting tools with solid additives are summarized, providing a foundation for further research.

Keywords: Ceramic tools; Self-lubrication; Self-repairing; Service life; Toughening and strengthening

Perspective

19 July 2024

Disentangling Human Nature: Environment, Evolution and Our Existential Predicament

Throughout our entire evolutionary history, the physical environment has played a significant role in shaping humans’ subsistence adaptations. As early humans began to colonise novel biomes and construct ecological niches, their behavioural flexibility appeared as an unquestionable fact. During the Late Pleistocene-Holocene transition, the shift from foraging to farming radically altered ecosystem services, resulting in increased exposure to zoonotic pathogens and the emergence of structural inequalities that pervade our current human condition in the Anthropocene epoch. The article seeks to use an anthropological biosocial analysis to explore the diverse evolutionary paths humans have taken, which in turn shape their relationships with the natural world. Given the enigmatic nature of human behavior, it is essential to examine it holistically to understand how different subsistence patterns (e.g., intensive agriculture, foraging, and horticulture) have influenced resilience and adaptation to environmental challenges.

Keywords: Agriculture; Anthropocene; Anthropology; Evolution; Foraging; Holocene; Horticulture; Zoonoses

Review

16 July 2024

Mitochondrial Damage and Epithelial-Mesenchymal Transition as Major Triggers of the Development of Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a type of interstitial pneumonia with an unknown cause that progresses gradually, primarily affecting the elderly. The presence of fibrosis has significant implications for individuals with reduced lung compliance, resulting in decreased quality of life and limited survival. Although the exact mechanism remains unclear, researchers have investigated various factors, such as senescent telomerase replication and abnormal lung stem cell differentiation, to understand the root cause. Extensive research has consistently shown that IPF is closely linked to the dysfunction of alveolar epithelial cells. Current scientific studies on IPF cover a range of aspects including oxidative stress, endoplasmic reticulum stress, mitochondrial damage, and iron-induced apoptosis. By examining these mechanisms, a comprehensive model has been developed that explains the process of IPF. Oxidative stress is identified as the primary trigger, followed by mitochondrial damage as a central component, leading to the mesenchymal transformation of alveolar epithelial cells as the ultimate outcome. This model is expected to serve as a valuable reference for understanding the mechanism of IPF and guiding future drug development efforts.

Keywords: Idiopathic Pulmonary Fibrosis; Alveolar epithelial cell; Epithelial-Mesenchymal Transition; Oxidative Stress

Article

15 July 2024

Investigation of High Vibration Phenomena in Steam Turbine: An Experimental Exploration into Root Causes and Material Analysis

The steam turbine is a rotating device subject to axial and radial shaft shifts that can induce vibrations during operation. Tools such as monitoring systems and proximity probe sensors are essential to monitoring these vibrations. High vibrations affect the machine’s performance, increasing the risk of malfunctions and reducing its lifespan, and also pose risks to operational and maintenance personnel. The intensified vibrations in the bearing pedestals signify the underlying issues with the machine’s normal operation. Consequently, problems such as rotor imbalance, coupling misalignment, mechanical looseness, material failure, and bent shaft may be caused. In the current study, the latest field-proven automatic diagnostic of rotary equipment (ADRE 408) data acquisition system is installed by Bentley Nevada to investigate the root cause of high vibration. This advanced diagnostic system facilitates a comprehensive assessment, enabling us to effectively identify and address underlying problems. Hence, the current research includes a thorough diagnosis of the underlying problems to attenuate the risks of high vibrations in the steam turbine, coupled with strategic maintenance planning and corrective actions.

Keywords: Vibration analysis; Rotor imbalance; Material failure; Axial and radial shaft; ADRE 408

Review

11 July 2024

Photocatalytic Aerobic Conversion of Methane

The direct conversion of methane into high-value chemicals has been a persistent research focus in the fields of chemical engineering and energy. Photocatalysis, as an innovative technology, not only circumvents the issues of catalyst sintering and carbon deposition associated with traditional thermal catalysis but also transcends thermodynamic limitations by providing new reaction pathways. Utilizing molecular oxygen as an oxidant generates various reactive oxygen species, offering unique thermodynamic advantages for methane conversion. This review summarizes the advancements in photocatalytic partial oxidation (PPOM) and oxidative coupling of methane (POCM) using oxygen as an oxidant. It discusses the activation mechanisms and reaction pathways of methane and oxygen in different systems, as well as the application of photochemical cycling strategies in methane conversion. Finally, it addresses the challenges in this field, proposes potential solutions, and offers perspectives on the future development of photocatalytic systems.

Keywords: Photocatalysis; Methane; Oxygen; Partial Oxidation; Oxidative Coupling; Photochemical looping

Article

10 July 2024

Documenting the Changing Floodplain of Nileas Basin in North Euboea (Greece) before and after Storms Daniel and Elias

The area of north Euboea is characterized by its intense relief, dense hydrographic network, and rich flora and fauna. In the mid-2010s, the region was struck by a plane tree disease that withered the large population of plane trees in the area, while in 2021, a large wildfire completely burned the forest. These unfortunate events depleted the landscape’s natural ability to manage and mitigate flood phenomena. Observing the landscape’s vulnerability to floods, in April 2023, we conduct on-site field inspections in the rivers of the area. In September 2023, a major flood hit the area, causing in dramatic changes to the landscape. Therefore, in November 2023, we conducted follow-up on-site field inspections in the area, in order to trace the differences, present the damages the phenomenon left behind. These inspections allowed to document the landscape changes from the combination of all previous events and identify any associated pathologies. Site visits and comparisons before and after the Daniel/Elias storm revealed dramatic changes in the riverbed width at lower altitudes, significant sediment accumulation in the Voudouros River delta, alterations in the natural landscape along the river and its floodplain, destruction of the arable land, and road collapses in several locations.

Keywords: Hydraulics; On-site inspections; Floods; Plane trees disease; Wildfires

Communication

10 July 2024

Return Their Names to Forgotten Bones: Memory Process about Spanish Civil War in Ponferrada (León)

For more than 80 years, Spain has had a human rights problem. Since the 18th of July 1936, when military personnel and fascists staged a coup d’état against the democratic government of the Second Republic, thousands of victims remain missing. We will examine how the victims have been treated by the State and how civil society has led the process of recovering democratic memory. We will focus on its impact in the Bierzo region, in the northwest of the Iberian Peninsula, and its importance in this process. We will also look at how scientific efforts continue to search for missing persons. History, archaeology, physical anthropology, and genetics join forces to repair the victims of the Spanish Civil War and Franco’s dictatorship.

Keywords: Human Rights; Democratic Memory; Spanish Civil War; Francoist Dictatorship; Missing Persons; Ponferrada; El Bierzo

Book Review

09 July 2024

Article

05 July 2024

Does Philosophy Kill Humor?

The title of this paper poses a paradoxical question, relating philosophy and humor, and tries to be humorous itself with the use of the verb “kill”. Against a more common, sometimes even academical, view of philosophy as a tremendously serious, deep, and complex corpus of knowledgeall theory and no praxisthe article challenges this view and will try to explain why humor, when associated with philosophy, can accelerate the understanding of a concept, and reveal unexpected spaces for reflection while donating moments of lightness and entertainment. In this perspective, humor reveals itself as a fundamental anthropological experience strongly connected to human freedom. I am aware that there are many different types of humorirony, joke, slapstick, double-entendre, pun, deadpan-dry humor, etc., and also that the definition of “sense of humor” may be highly subjective, often related to the cultural profile of the person, and their geographical and historical contexts: what I consider funny, can be neutral or even offensive for another person. Nevertheless, among hundreds of interpretations, I will consider those which are more consistent with the scope of this paper. Moreover, if we think about the contemporary movement called philosophical counseling as a praxis that aims to help people in trouble and despair to see human problems from a wider and more rational Weltanschauung (view of the world), humor can become a useful tool to re-discover the frolicsome child inside ourselves: while playing with contrasts, metaphors, and metonymies, it induces a sudden, positive change of perspective. A process that is valid for both the counselor and the counselee, the self and the other: humor can provoke in the counselor a new and fresh way to understand the counselee’s difficulty; for the client, it can be a moment of tension release, or the start of a different way to address and approach life’s problems, or, even more, the beginning of a creative, transformative path.

Keywords: Humor; Comedy; Tragedy; Thought; Laughter; Freedom
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