Derivation of lithofacies from geophysical logs : a review of methods from manual picking to machine learning

The aims of this report are to document: 1. A range of methods that are currently used by the BGS stratigraphers to extract lithological information from geophysical logs (includes manual classification, cut-off analysis, mineral composition by linear inversion). 2. Alternative methods which, at present, are not routinely applied but are sufficiently practical and accessible that they could become important, including unsupervised (k-mean clustering) and supervised machine learning approaches. The report does not aim or claim to be a complete inventory of all possible methods to derive lithological information from geophysical logs. The authors welcome correspondence and information on any additional methods that are available or emerging

Genomic investigations of unexplained acute hepatitis in children

Since its first identification in Scotland, over 1,000 cases of unexplained paediatric hepatitis in children have been reported worldwide, including 278 cases in the UK1. Here we report an investigation of 38 cases, 66 age-matched immunocompetent controls and 21 immunocompromised comparator participants, using a combination of genomic, transcriptomic, proteomic and immunohistochemical methods. We detected high levels of adeno-associated virus 2 (AAV2) DNA in the liver, blood, plasma or stool from 27 of 28 cases. We found low levels of adenovirus (HAdV) and human herpesvirus 6B (HHV-6B) in 23 of 31 and 16 of 23, respectively, of the cases tested. By contrast, AAV2 was infrequently detected and at low titre in the blood or the liver from control children with HAdV, even when profoundly immunosuppressed. AAV2, HAdV and HHV-6 phylogeny excluded the emergence of novel strains in cases. Histological analyses of explanted livers showed enrichment for T cells and B lineage cells. Proteomic comparison of liver tissue from cases and healthy controls identified increased expression of HLA class 2, immunoglobulin variable regions and complement proteins. HAdV and AAV2 proteins were not detected in the livers. Instead, we identified AAV2 DNA complexes reflecting both HAdV-mediated and HHV-6B-mediated replication. We hypothesize that high levels of abnormal AAV2 replication products aided by HAdV and, in severe cases, HHV-6B may have triggered immune-mediated hepatic disease in genetically and immunologically predisposed children

Plio‐Pleistocene fault reactivation within the Crag Basin, eastern UK : implications for structural controls of landscape development within an intraplate setting

This study examines the long‐term neotectonic evolution of the Crag Basin of eastern England during the Plio‐Pleistocene (c. 4.0–0.48 Ma) and the influence of neotectonics on coastal and drainage development. The Crag Basin was situated within the western margins of the southern North Sea with palaeogeography influenced by changes in global sea‐level and longer‐term regional‐scale neotectonic uplift and subsidence. This study identifies an additional local‐scale neotectonic control on basin development with localized crustal displacement occurring along normal faults. Plio‐Pleistocene movement along these faults was accommodated by partial dip‐slip (normal) reactivation of an Oligocene‐age (Pyrenean) dextral strike‐slip shear zone, which in turn was inherited from much older Caledonian orogenic crustal structure. Fault displacement was driven by sediment‐loading reflecting enhanced landscape denudation under progressively deteriorating climates and increased rates of erosion/sedimentation. Faulting acted to regulate accommodation space, controlling sedimentation patterns and the courses of major preglacial drainage systems including the Kesgrave Thames and Bytham rivers. The lower reaches of both river systems are considered to have been confluent in the Crag Basin during much of the Early Pleistocene with their lower reaches structurally controlled. Divergence occurred at c. 0.9 Ma with the lower reaches of the Bytham utilizing the former Bytham‐Thames valley and the Kesgrave Thames adopting progressively more southern routes, aligned to the axis of subsidence within the London Basin. The study highlights the significance of tectonic inheritance in driving recent neotectonic crustal deformation and its influence on sedimentation patterns and drainage development within an intraplate setting

Adeno-associated virus 2 infection in children with non-A–E hepatitis

An outbreak of acute hepatitis of unknown aetiology in children was reported in Scotland1 in April 2022 and has now been identified in 35 countries2. Several recent studies have suggested an association with human adenovirus with this outbreak, a virus not commonly associated with hepatitis. Here we report a detailed case–control investigation and find an association between adeno-associated virus 2 (AAV2) infection and host genetics in disease susceptibility. Using next-generation sequencing, PCR with reverse transcription, serology and in situ hybridization, we detected recent infection with AAV2 in plasma and liver samples in 26 out of 32 (81%) cases of hepatitis compared with 5 out of 74 (7%) of samples from unaffected individuals. Furthermore, AAV2 was detected within ballooned hepatocytes alongside a prominent T cell infiltrate in liver biopsy samples. In keeping with a CD4+ T-cell-mediated immune pathology, the human leukocyte antigen (HLA) class II HLA-DRB1*04:01 allele was identified in 25 out of 27 cases (93%) compared with a background frequency of 10 out of 64 (16%; P = 5.49 × 10−12). In summary, we report an outbreak of acute paediatric hepatitis associated with AAV2 infection (most likely acquired as a co-infection with human adenovirus that is usually required as a ‘helper virus’ to support AAV2 replication) and disease susceptibility related to HLA class II status. © 2023, The Author(s), under exclusive licence to Springer Nature Limited