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Hobnail hemangioma-a systematic review and a case report of an intraoral lesion with Dabska tumor-like features
No full textAbstract
Hobnail hemangioma is a rare, benign vascular neoplasm. Intraoral lesions are extremely rare. To date, only seven intraoral cases of hobnail hemangiomas and two intraoral cases of Dabska tumors have been described in the English-language literature. This article presents a hobnail hemangioma case with papillary intralymphatic angioendothelioma (Dabska tumor)-like features on the gingiva of a 7-year-old female. Hobnail hemangiomas are benign lesions, but they display worrisome features on microscopic examination and can be confused with malignant vascular neoplasms. Histologically hobnail hemangiomas demonstrate superficial dilated, vascular structures with prominent hobnail endothelial cells and deeper, collagen dissecting thinner neoplastic vessels which in some cases may raise a worrisome pseudoangiosarcomatous histologic view. It is important to set an accurate diagnosis of hobnail hemangioma to diminish the risk of diagnosing these lesions as malignant tumors thus avoiding unnecessarily aggressive therapy.Abstract
Hobnail hemangioma is a rare, benign vascular neoplasm. Intraoral lesions are extremely rare. To date, only seven intraoral cases of hobnail hemangiomas and two intraoral cases of Dabska tumors have been described in the English-language literature. This article presents a hobnail hemangioma case with papillary intralymphatic angioendothelioma (Dabska tumor)-like features on the gingiva of a 7-year-old female. Hobnail hemangiomas are benign lesions, but they display worrisome features on microscopic examination and can be confused with malignant vascular neoplasms. Histologically hobnail hemangiomas demonstrate superficial dilated, vascular structures with prominent hobnail endothelial cells and deeper, collagen dissecting thinner neoplastic vessels which in some cases may raise a worrisome pseudoangiosarcomatous histologic view. It is important to set an accurate diagnosis of hobnail hemangioma to diminish the risk of diagnosing these lesions as malignant tumors thus avoiding unnecessarily aggressive therapy
Dementian havaitseminen ja alatyyppien toisistaan erottaminen käyttäen Raman spektroskopiaa ja hien ekstrasellulaarisia vesikkeleitä
No full textProfiting from Innovation Process – Capturing Value from Evolving Artificial Intelligence
No full textAbstract
General-purpose technologies (GPTs), such as AI, have significant economic and societal importance. However, many prevailing theories and models, primarily derived from studying discrete (narrowly applicable) technologies, fall short in addressing GPTs with their distinctive characteristics. A longitudinal narrative study of the IBM Watson case turns attention to profiting from the innovation process rather than profiting from innovation (output), which marks a deviation from earlier theorizing. The study further shows that profiting from innovation process is associated with complementary asset bias and option value of openness, as well as to business and performance risks related to the initial use case selection for developing GPTs that may exhibit notable cost of errors. By addressing special characteristics of GPTs from the point of view of innovators benefiting from innovation, and connecting the general-purpose technology development to temporal aspects of value capture, this study enriches the innovation management literature and informs practical applications.Abstract
General-purpose technologies (GPTs), such as AI, have significant economic and societal importance. However, many prevailing theories and models, primarily derived from studying discrete (narrowly applicable) technologies, fall short in addressing GPTs with their distinctive characteristics. A longitudinal narrative study of the IBM Watson case turns attention to profiting from the innovation process rather than profiting from innovation (output), which marks a deviation from earlier theorizing. The study further shows that profiting from innovation process is associated with complementary asset bias and option value of openness, as well as to business and performance risks related to the initial use case selection for developing GPTs that may exhibit notable cost of errors. By addressing special characteristics of GPTs from the point of view of innovators benefiting from innovation, and connecting the general-purpose technology development to temporal aspects of value capture, this study enriches the innovation management literature and informs practical applications
Metaanipyrolyysillä ja elektrolyysillä tuotetun vedyn ympäristövaikutusten vertailu
No full textHydrogen is becoming more relevant than ever, due to the global pursuit to lower greenhouse gas emissions. The European Union has published its hydrogen strategy, pursuing the scale-up of low-emission hydrogen production. In this strategy, electrolysis using renewable energy is a key part. In its own national strategy, Finland also seeks to move towards a more hydrogen-powered energy system.
In this study, methane pyrolysis and water electrolysis were studied through a literature review to find out what the environmental impacts related to each production method are and how the impacts compare to each other. The study discussed multiple methods for producing hydrogen through methane pyrolysis and highlighted the environmental concerns associated with hydrogen production via methane pyrolysis. Natural gas dependency is one of the biggest sources of emissions in methane pyrolysis production. Impacts also vary significantly between different methane pyrolysis technologies. On the other hand, electrolysis is also not a completely problem-free solution. It can cause greenhouse gas emissions depending on the source of electricity. Electrolysis also uses water as a feedstock which raises concerns about water usage. This study showed that methane pyrolysis has the potential to compete with electrolysis. A comparison from Finland’s perspective showed that methane pyrolysis can also have low emissions. Methane pyrolysis can have lower electricity consumption during the production phase, and even with natural gas transportation included, methane pyrolysis can have around the same amount of emissions as water electrolysis. Based on the comparison, methane pyrolysis should be considered alongside electrolysis when choosing low-emissions hydrogen production methods
Clinical Applications of Extracellular Vesicles: Promises and Pitfalls
No full textAbstract
Extracellular vesicles (EVs) are membrane-bound nanoparticles released by almost all cell types into the extracellular space, acting as important mediators of intercellular communication by transferring proteins, lipids, and nucleic acids horizontally. EVs are generally classified into small EVs (200 nm), microvesicles, and apoptotic bodies, with current classification methods focusing on physical properties, molecular composition, and cellular origin, as detailed in the MISEV2023 guidelines. EVs are highly promising for diagnostic and therapeutic applications due to their intrinsic biocompatibility, stability in biological fluids, capacity to carry diverse molecular cargo, and potential for drug delivery and functionalization to enable targeted delivery and tissue repair. This narrative review discusses the emerging roles of EVs across various medical fields, including obstetrics and gynecology, ophthalmology, otorhinolaryngology, urology, oncology, orthopedics, neurology, immunology, wound healing, chronic pain management, dermatology, and cardiology. In each discipline, EVs show potential as biomarkers for diagnosing physiological or pathological conditions and as carriers for targeted drug delivery and regenerative treatments. Exosomes, a major type of small EVs, have especially attracted attention as versatile nanocarriers for precision medicine. However, translation into clinical practice requires addressing key pitfalls, including the standardization of isolation and characterization protocols, dose definition, GMP-compliant large-scale production, and regulatory approval. Ongoing interdisciplinary collaboration across disciplines and thorough clinical testing will be essential to unlock the full biomedical potential of EVs and establish them as transformative tools in personalized healthcare.Abstract
Extracellular vesicles (EVs) are membrane-bound nanoparticles released by almost all cell types into the extracellular space, acting as important mediators of intercellular communication by transferring proteins, lipids, and nucleic acids horizontally. EVs are generally classified into small EVs (200 nm), microvesicles, and apoptotic bodies, with current classification methods focusing on physical properties, molecular composition, and cellular origin, as detailed in the MISEV2023 guidelines. EVs are highly promising for diagnostic and therapeutic applications due to their intrinsic biocompatibility, stability in biological fluids, capacity to carry diverse molecular cargo, and potential for drug delivery and functionalization to enable targeted delivery and tissue repair. This narrative review discusses the emerging roles of EVs across various medical fields, including obstetrics and gynecology, ophthalmology, otorhinolaryngology, urology, oncology, orthopedics, neurology, immunology, wound healing, chronic pain management, dermatology, and cardiology. In each discipline, EVs show potential as biomarkers for diagnosing physiological or pathological conditions and as carriers for targeted drug delivery and regenerative treatments. Exosomes, a major type of small EVs, have especially attracted attention as versatile nanocarriers for precision medicine. However, translation into clinical practice requires addressing key pitfalls, including the standardization of isolation and characterization protocols, dose definition, GMP-compliant large-scale production, and regulatory approval. Ongoing interdisciplinary collaboration across disciplines and thorough clinical testing will be essential to unlock the full biomedical potential of EVs and establish them as transformative tools in personalized healthcare
Epätoivon tuolla puolen : eksistentiaaliset vastaukset Kierkegaardilla ja Nietzschellä
No full textThis master’s thesis examines existential despair as an ontological condition arising from heightened self-consciousness and analyzes philosophical responses to this condition in the thought of Friedrich Nietzsche and Søren Kierkegaard. It argues that existential despair emerges inevitably from human self-reflection within an apparently meaningless universe, yet need not culminate in resignation. Instead, despair can be transformed through passionate commitment to an authentic mode of existence.
The ontological basis of despair is developed through engagement with Martin Heidegger’s phenomenology, Arthur Schopenhauer’s philosophical pessimism, and Peter Wessel Zapffe’s conception of consciousness as a “damaging surplus.” Literary analyses of Pär Lagerkvist and Leo Tolstoy further illustrate how sustained self-questioning destabilizes inherited structures of meaning, leading individuals through identifiable phases—awakening, disintegration, and alienation—toward confrontation with cosmic insignificance.
Nietzsche’s response to existential despair centers on his diagnosis of nihilism in the wake of the “death of God” and his call for an affirmative stance toward life. Concepts such as tragic optimism, eternal recurrence, amor fati, and the will to power articulate a vision of self-overcoming grounded in the acceptance of finitude. The figure of the Übermensch functions allegorically as a synthesis of Apollonian consciousness and Dionysian vitality. Despite enduring interpretive challenges, Nietzsche’s framework offers a naturalistic path that affirms embodied existence without recourse to supernatural foundations. Kierkegaard, by contrast, grounds his response in an account of the human self as a synthesis of opposing dimensions—finite and infinite, temporal and eternal, necessity and possibility, body and soul. For him, despair appears as the “sickness unto death,” arising from a failure to relate these dimensions properly to their divine ground. His stages of existence chart a movement from aesthetic immediacy through ethical responsibility to religious authenticity, attainable only through the passionate “leap of faith” in which eternity intersects time, a framework that ultimately presupposes Christian commitment.
While acknowledging the fundamental metaphysical incompatibility between Nietzsche and Kierkegaard, the thesis identifies significant structural affinities in their responses to despair. Both thinkers reject purely rational solutions, insist on the integration rather than elimination of suffering, and conceive existence as a continuous task rather than a problem to be solved. On this basis, the thesis proposes an integrative framework at the level of existential praxis, emphasizing phenomenological acknowledgment, cultural critique, passionate commitment, embodied affirmation, and ongoing striving. It concludes that existential despair is not a pathological anomaly but an inescapable dimension of self-conscious human life, within which meaning emerges through sustained and honest engagement, eschewing aspirations of a comprehensive final resolution
Mechanical performance and failure mechanisms of self-piercing riveted AA6061-T6 joints with varying sheet thickness configurations
No full textAbstract
This study investigates the influence of sheet thickness and stacking configuration on the formation, quality, and mechanical performance of self-piercing rivet (SPR) joints in AA6061-T6 aluminum sheets. SPR joints were fabricated under controlled, constant process parameters to clarify the effects of upper and lower sheet thickness. Experimental trials were complemented with a validated 2D axisymmetric finite element model to analyze rivet penetration, flaring, and stress–strain evolution. Joint quality indices, including undercut, remaining thickness, and rivet head height, were evaluated alongside microstructural deformation patterns and failure modes. Results demonstrate that thinner upper sheets over thicker lower sheets enhance undercut formation and rivet interlock, while thicker lower sheets reduce strain localization and promote uniform deformation. For configurations with a thick upper sheet, optimized rivet and die geometries were proposed to improve upper sheet piercing and joint quality. Stress analysis revealed that rivet tip and lower sheet regions experience the highest plastic deformation, controlling piercing and mechanical interlock behavior. A regression-based statistical model was developed to predict joint quality indices with high accuracy (MAPE 10%) and robustness, enabling systematic optimization of SPR joints. The study provides mechanistic insights into SPR joint formation, highlighting the critical role of sheet thickness configuration, and establishes practical guidelines for designing robust SPR joints for lightweight structural applications.Abstract
This study investigates the influence of sheet thickness and stacking configuration on the formation, quality, and mechanical performance of self-piercing rivet (SPR) joints in AA6061-T6 aluminum sheets. SPR joints were fabricated under controlled, constant process parameters to clarify the effects of upper and lower sheet thickness. Experimental trials were complemented with a validated 2D axisymmetric finite element model to analyze rivet penetration, flaring, and stress–strain evolution. Joint quality indices, including undercut, remaining thickness, and rivet head height, were evaluated alongside microstructural deformation patterns and failure modes. Results demonstrate that thinner upper sheets over thicker lower sheets enhance undercut formation and rivet interlock, while thicker lower sheets reduce strain localization and promote uniform deformation. For configurations with a thick upper sheet, optimized rivet and die geometries were proposed to improve upper sheet piercing and joint quality. Stress analysis revealed that rivet tip and lower sheet regions experience the highest plastic deformation, controlling piercing and mechanical interlock behavior. A regression-based statistical model was developed to predict joint quality indices with high accuracy (MAPE 10%) and robustness, enabling systematic optimization of SPR joints. The study provides mechanistic insights into SPR joint formation, highlighting the critical role of sheet thickness configuration, and establishes practical guidelines for designing robust SPR joints for lightweight structural applications