Search Results (10)

The aim of this research is to investigate and use a variety of immersive multisensory media techniques in order to create convincing digital models of fossilised tree trunks for use in XR (Extended Reality). This is made possible through the use of geospatial data derived from aerial imaging using UASs, terrestrial material captured using cameras and the incorporation of both the visual and audio elements for better immersion, accessed and explored in 6 Degrees of Freedom (6DoF). Immersiveness is a key factor of output that is especially engaging to the user. Both conventional and alternative methods are explored and compared, emphasising the advantages made possible with the help of Machine Learning Computational Photography. The material is collected using both UAS and terrestrial camera devices, including a multi-sensor 3D-360° camera, using stitched panoramas as sources for photogrammetry processing. Difficulties such as capturing large free-standing objects using terrestrial means are overcome using practical solutions involving mounts and remote streaming solutions. The key research contributions are comparisons between different imaging techniques and photogrammetry processes, resulting in significantly higher fidelity outputs. Conclusions indicate that superior fidelity can be achieved through the help of Machine Learning Computational Photography processes, and higher resolutions and technical specs of equipment do not necessarily translate into superior outputs. Full article

Diagenetic spheroids are rounded mineralised structures in sedimentary rocks that span several orders of size dimensions. These objects include rosettes spanning tens of micrometres; millimetre-sized granules; and centimetre- to metre-scale botryoids, nodules, and concretions. Connections between diagenetic spheroids and chemically oscillating reactions (COR) have been established based on chemical and pattern similarities. Nevertheless, it is unknown if there are variations in their occurrences throughout geological time, especially during periods of global environmental change. This is because COR are pattern-forming reactions where carboxylic acids are decarboxylated by strong oxidants like sulphuric acid, bromate, or iodate. The hypothesis is that there should be a greater number of diagenetic spheroids at periods of increased atmospheric and oceanic oxygenation levels. Hence, this work presents the first compilation of occurrences of diagenetic spheroids between 0.541 and 1.8 billion years ago (Ga). The compiled patterned objects are those with concentric laminations and radially aligned crystals, which are patterns akin to equidistant circularly concentric waves that radially diffuse in COR. Another characteristic of diagenetic spheroids, similar to that found in botryoidal minerals, is the destructive interference that forms circular twins; this is identical to the COR pattern formed when circular waves meet. The timeline of Proterozoic diagenetic spheroids produced in this work reveals a significant increase in occurrences across the Ediacaran, which is attributed to an increased environmental oxidation state. During this interval, seawater is known to have become richer in sulphate and iodate, which create ideal conditions for the abiotic and diagenetic oxidation of biomass. Therefore, increased occurrences of diagenetic spheroids in the Neoproterozoic possibly represent sedimentological evidence for abiotic decarboxylation reactions and widespread COR in productive environments. The distribution of diagenetic spheroids observed during the Proterozoic may also be more broadly applicable to other epochs of Earth’s history. Full article

This study explores the potential of biosilica including diatom and diatomaceous earth as alternative silica sources for metakaolin-based geopolymers. Diatomaceous earth, composed of fossilised diatom frustules rich in amorphous silica, and diatoms, a sustainable source of renewable biosilica, are investigated for their effectiveness in enhancing geopolymer properties. Through detailed analyses including FTIR, XRD, and SEM, the study evaluates the impact of these biosilica sources on geopolymer compressive strength and microstructure, comparing them with conventional sodium silicate. Results show that diatoms exhibit significant promise, achieving 28-day strength up to 17.9 MPa at a 30% mass fraction, while diatomaceous earth reaches 26.2 MPa at a 50% addition rate, demonstrating their potential as active silica sources. Furthermore, the study elucidates the role of organic matter in biosilica on geopolymerisation, highlighting its influence on active silica release and the strength performance of products. This study proposes a novel pathway to enhance the sustainability of geopolymers through the utilisation of biosilica from diatoms, contributing to advancements in eco-efficient construction materials. Full article

Paleo-oncology studies neoplastic diseases in fossilised animals, including human remains. Recent advancements have enabled more accurate diagnoses of ancient pathologies despite the inherent challenges in identifying tumours in fossils—such as the rarity of well-preserved specimens, the predominance of bone remains, and the difficulty in distinguishing neoplastic from non-neoplastic lesions. This study compiles reports of tumours in fossilised animals, highlighting that neoplasms are present in a wide range of vertebrates and drawing comparisons to modern instances of similar diseases. The findings underscore the multifactorial aetiology of tumours, which involves genetic, environmental, and lifestyle factors, and suggest that tumours have been around for at least 350 million years. Full article

Fossil leaf anatomy has previously been used as a proxy for paleoclimate. However, the exposure of leaves to sun or shade during their growth can lead to morphotype differences that confound the interpretation of fossil leaf anatomy in relation to climate and prevent reliable paleoclimate reconstruction. This work aims to model the differences in leaf anatomy that are due to various climatic drivers and differences attributable to sun or shade positions, using Nothofagus cunninghamii as the model species. Leaves from the sun and shade parts of three trees have been sampled from each of 11 sites in Victoria and Tasmania, Australia. The gross morphological and cuticular features have been scored and modelled with climate data from the sites. Random forest models can accurately predict Nothofagus cunninghamii contemporary climatic conditions of the spring temperature and summer rainfall based on leaf anatomical measurements. Leaf area, stomatal density and epidermal cell density are the most accurate predictors of whether a leaf grew in the sun or shade. Leaf area is also the strongest predictor of the maximum and minimum spring temperatures and rainfall. The models have implications for the use of fossilised leaves in paleoclimate reconstruction. The models we have built can be used to effectively predict whether a fossil leaf was from a sun or shade position on the tree and thus enable more reliable inference of paleoclimate by removing the confounding issues of variable leaf anatomy due to sun exposure during growth. Finally, these models could conceivably be used to make predictions of past paleoclimatic conditions provided suitable training and validation data on climatic conditions are available. Full article

Ever since Estácio da Veiga, at the end of the 19th century, identified the ruins of the Roman city of Balsa under Torre d’Aires estate (Luz de Tavira-Portugal) and its surroundings, the scientific questions about this Roman city have been constantly increasing. Despite the historical importance of this city, referenced in classical literature, the archaeological knowledge about it remains very scarce due to the difficulties around implementing any durable scientific research projects. Therefore, much of that written about the topographical features and configuration of the city has no unequivocal scientific support. Finally, 2019 saw the launch of this ongoing project “Balsa, searching for the origins of the Algarve”, which aims to ascertain the main features concerning the city’s extent and configuration, mainly through non-invasive methods. Since 2017, geomagnetic and geo-radar surveys have spanned several hectares and successfully identified many traces of the Roman city while discarding the existence of others in certain locations. In the last two years, the geo-radar surveys have intensified and established the boundaries to the Roman city as well as parts of its layout, remnants of buildings, and even fossilised agricultural crops in addition to other geophysical anomalies, whether or not they are subsequently confirmed by diagnostic pits. Full article

Patients with type 2 diabetes mellitus (T2DM) and/or cardiovascular disease (CVD), conditions of hyperinsulinaemia, have lower levels of osteocalcin and bone remodelling, and increased rates of fragility fractures. Unlike osteoporosis with lower bone mineral density (BMD), T2DM bone fragility “hyperinsulinaemia-osteofragilitas” phenotype presents with normal to increased BMD. Hyperinsulinaemia and insulin resistance positively associate with increased BMD and fragility fractures. Hyperinsulinaemia enforces glucose fuelling, which decreases NAD+-dependent antioxidant activity. This increases reactive oxygen species and mitochondrial fission, and decreases oxidative phosphorylation high-energy production capacity, required for osteoblasto/cytogenesis. Osteocytes directly mineralise and resorb bone, and inhibit mineralisation of their lacunocanalicular space via pyrophosphate. Hyperinsulinaemia decreases vitamin D availability via adipocyte sequestration, reducing dendrite connectivity, and compromising osteocyte viability. Decreased bone remodelling and micropetrosis ensues. Trapped/entombed magnesium within micropetrosis fossilisation spaces propagates magnesium deficiency (MgD), potentiating hyperinsulinaemia and decreases vitamin D transport. Vitamin D deficiency reduces osteocalcin synthesis and favours osteocyte apoptosis. Carbohydrate restriction/fasting/ketosis increases beta-oxidation, ketolysis, NAD+-dependent antioxidant activity, osteocyte viability and osteocalcin, and decreases excess insulin exposure. Osteocalcin is required for hydroxyapatite alignment, conferring bone structural integrity, decreasing fracture risk and improving metabolic/endocrine homeodynamics. Patients presenting with fracture and normal BMD should be investigated for T2DM and hyperinsulinaemia. Full article

Fish fossilisation is relatively poorly known, and skeletal element modifications resulting from predation, burial and diagenesis need to be better investigated. In this article, we aim to provide new results about surface, structural and chemical changes in modern and fossil fish bone. Fossil samples come from two distinct localities of roughly the same age in the Pliocene–Pleistocene Chiwondo Beds adjacent to Lake Malawi. Optical and scanning electron microscope (SEM) observations, energy dispersive spectroscopy (EDS) analyses and Fourier transform infrared (FTIR) spectrometry were carried out on three categories of fish bones: (i) fresh modern samples collected in the lake, (ii) extracted from modern fish eagle regurgitation pellets, and (iii) fossils from Malema and Mwenirondo localities. A comparison of these data allowed us to detect various modifications of bone surfaces and structure as well as composition changes. Some differences are observed between fresh bones and modern pellets, and between pellets and fossils. Moreover, fossil fish bone surface modifications, crystallinity, and chemical composition from Malema and Mwenirondo differ despite their chronological and spatial proximities (2.5–2.4 Ma, 500 m). In both sites, the post-predation modifications are strong and may hide alterations due to the predation by bird of prey such as the fish eagle. The combination of the used methods is relevant to analyses of diagenetic alterations in fish bones. Full article

This paper looks into the 200-year history of a particular Christian dress form in Finland, namely the körtti dress. Emerging from a declining peasant dress style, this supposedly unchanging and fossilised signifier of a revivalist Protestant movement has in fact gone through numerous transformations influenced by both socio-political and religious trends as well as fashion-driven and materially-ordained factors. From the analysis emerge four key factors that influence how dress strategies are formulated and enacted within a religious movement: (1) how vulnerable or institutionalised the movement is; (2) how it is viewed by those external to it; (3) how the members of the movement want themselves to preserve or change the movement and its public image; (4) and how external fashion processes infiltrate the tastes and sensibilities of the members. It is concluded that elements considered ‘traditional’, ‘modern’, ‘secular’ and ‘religious’ may all be present at the same time in a dress phenomenon, indicating that fashion’s association with modern secularity is not as clear-cut as is sometimes thought. Full article

In the vast majority of fossils, the organic matter is degraded with only an impression or cast of the organism remaining. In rare cases, ideal burial conditions result in a rapid fossilisation with an exceptional preservation of soft tissues and occasionally organic matter. Such deposits are known as Lagerstätten and have been found throughout the geological record. Exceptional preservation is often associated with finely crystalline quartz (e.g., cherts), fine sediments (e.g., muds) or volcanic ashes. Other mechanisms include burial in anoxic/euxinic sediments and in the absence of turbidity or scavenging. Exceptional preservation can also occur when an organism is encapsulated in carbonate cement, forming a concretion. This mechanism involves complex microbial processes, resulting in a supersaturation in carbonate, with microbial sulfate reduction and methane cycling the most commonly suggested processes. In addition, conditions of photic zone euxinia are often found to occur during concretion formation in marine environments. Concretions are ideal for the study of ancient and long-extinct organisms, through both imaging techniques and biomolecular approaches. These studies have provided valuable insights into the evolution of organisms and their environments through the Phanerozoic and have contributed to increasing interest in fields including chemotaxonomy, palaeobiology, palaeoecology and palaeophysiology. Full article