Paleoarchean stromatolites are among the oldest compelling evidence for life. We present advanced two- and three-dimensional (2-D and 3-D) reconstructions of the morphology, mineralogy, trace element geochemistry, and taphonomy of permineralized stromatolites from the lowermost horizons of the ca. 3.5 Ga Dresser Formation, Pilbara, Western Australia. Rare earth element plus yttrium compositions suggest a restricted paleodepositional setting influenced by marine influxes; this contrasts with other Dresser stromatolites, which developed around terrestrial hot springs. Mineral phase relationships and positive Eu anomalies denote syndepositional hydrothermal influence and silicification promoting high-fidelity microstructural preservation. Although no primary kerogen is preserved, numerous 2-D and 3-D morphological characteristics denote a biogenic origin, including the onlap of sedimentary layers onto stromatolitic topography, fine-scale undulatory laminations, non-isopachous laminations with crestal thickening, laminoid fenestrae, and subvertical pillar-like fabrics interpreted as microbial palisade structure; these features suggest that the stromatolite eco-system was dominantly phototrophic. The deep iron-rich weathering profile of the Dresser stromatolites makes them pertinent analogues for potential microbialites in altered carbonates on Mars. Were similar putative biogenic macro-, meso- and micromorphologies identified in habitable Martian settings by rover imaging systems, such materials would be compelling targets for sample return.

Fracture dating is an issue at the forefront of forensic sciences. While dating fracture is crucial to understanding and verifying the chronology of events in cases of abuse and violent death, its application is the subject of considerable discussion in the scientific community, filled with limitations and difficulties. Current methods for fracture dating are mainly based on a qualitative assessment through macroscopy, microscopy, and imaging and subject to variations depending on the experience of the observer. In this paper, we investigated the potential of quantifiable micro-CT analysis for fracture dating. Five histomorphometric parameters commonly used for the study of the 3D bone trabecular microarchitecture with micro-CT were calculated based on nine fractures of known post-traumatic ages, including the degree of anisotropy, connectivity density, bone volume fraction, trabecular thickness, and trabecular separation. As a result, trends in the evolution of the microarchitecture of the bone relative to age of the callus could be identified, in particular concerning anisotropy, trabecular separation and connectivity density, consistent with the healing bone process. The findings obtained in this pilot study encourage further research in quantifiable parameters of the bone microarchitecture as they could represent useful features for the construction of objective models for fracture dating.

Mycotoxins represent a serious risk for human and animal health. Οchratoxin A (OTA) is a carcinogenic mycotoxin produced by A. carbonarius that constitutes a severe problem for viticulture. In this study, we investigate the development of novel detection and on-line monitoring approaches for the detection of OTA in the field (i.e. out of the chemical laboratory) using advanced molecular sensing. Both stand-alone and hyphenated mass spectrometry (MS) based systems (e.g. Time-of-Flight ToF–MS and gas chromatography GC combined with MS) and compact portable membrane inlet MS (MIMS) have been employed for the first time to detect and monitor volatile emissions of grape berries infected by the fungus Aspergillus carbonarius. In vacuo (electron impact—EI) and ambient ionisation (electrospray ionisation—ESI) techniques were also examined. On-line measurements of the volatile emissions of grape berries, infected by various strains of A. carbonarius with different toxicity levels, were performed resulting in different olfactory chemical profiles with a common core of characteristic mass fragments, which could be eventually used for on-site detection and monitoring allowing consequent improvement in food security.

Cement-based materials are a vital part of active or abandoned CO2 injection wells and their chemical and mechanical stability is a prerequisite for a wider implementation of carbon capture and geological storage (CCGS). Previous research has revealed the diffusion-controlled alteration mechanisms of various cementitious grouts in CO2-rich environments at various regimes of temperatures, pressures, salinities and pH. In the present paper the main focus are the chemical interactions between a realistic CO2-saturated pore-water (Utsira formation) with class G cement samples at 8MPa for two bottom-hole temperatures (333K, 393K). The carbonation front at 393K was doubled in depth in comparison to 333K, though for both temperatures the overall cement microstructure appeared to remain relatively intact with probable good sealing capacity for properly cemented abandoned wells. Calcium leaching depths for both 333K and 393K were almost identical, with the higher temperature showing evidence of generation of additional barriers to further CO2 inflow. Finally, chloride penetration was found to be independent of the carbonation reactions