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Large clastic dykes (the Harutori‐Taro and Harutori‐Jiro dykes) and smaller dykes are exposed in the underground Kushiro Coal Mine (KCM), Japan. This study examines these dykes as a case study to investigate the geological conditions and fluid flow history that lead to the development of large clastic dykes in basins. The composition of the dykes indicates the Beppo and/or Harutori formations as their parent unit. Crystallite size distribution (CSD) analysis reveals Ostwald ripening of the kaolinite in the kaolinitised feldspar from the dykes, suggesting stagnant conditions in the parent unit before the dyke was formed. In contrast, smectite CSDs and the high carbonate content of the dykes suggest that large volumes of fluid flowed through the dykes along the established hydraulic gradient, which was triggered by the breaking of the upper seal. The isotopic and chemical compositions of the calcite and aragonite in the dykes, with moderate siderite and rhodochrosite content, indicate the fluid was a warm (>30°C) mixture of freshwater and saltwater, which was transferred from deeper levels of the parent unit towards the crest of an anticline. Immediately after sand injection, the semi‐closed system of the parent unit near the root of the large dyke was transformed into a major flow channel for overpressurised fluids. Subsequently, a large volume of fluid flowed along the vertical conduit (or dyke) over a long period of time (>1 Myr), which removed fluid from a widespread area (i.e., several hundred square kilometres) of the basin. The results show that thin parent units, poor lateral continuity of the upper seal, and spatially heterogeneous overpressurisation do not preclude the formation of large dykes. [ABSTRACT FROM AUTHOR]

Both igneous and sedimentary rocks affected by water–rock interaction commonly form rhythmic Fe‐oxide bands that provide information on palaeo‐groundwater. This study investigated the formation of Fe‐oxide banded patterns of concentrically banded concretions from the Jurassic Navajo Sandstone (United States) and banded claystone 'zebra rock' from the Neoproterozoic Johnny Cake Shale Member (Western Australia). Micro‐X‐ray fluorescence imaging of both samples revealed uniformly banded patterns of asymmetrical Fe content peaks. This study proposes that their formations were caused by diffusion, with a pH buffering reaction of Fe2+ and O2 due to dissolution of earlier materials by acidic fluids. Based on the model, it is suggested that the acid fluids for Navajo diffused towards the inner side of the concretion, and that for Kimberley they penetrated oblique or perpendicular to bedding. In addition, the Fe‐oxide precipitation has resulted from pH rises of acidic fluids because of diagenetic alteration of earlier calcite concretion in Navajo and that of earlier pyrite‐bearing claystone in Kimberley. The interpretation for Kimberley is based on the δ34S values (<−20‰) of zebra rock, suggesting that the alunite and Fe‐oxide resulted from the supply of SO42− and Fe2+ produced as a result of pyrite oxidation in earlier rocks. The formation rate of the Fe‐oxide band was estimated from the constant width of the Fe peaks and the expected diffusion coefficient for Fe2+ through the rock matrix, and it was found to be on the order of years for Navajo and on the order of tens of years for Kimberley. [ABSTRACT FROM AUTHOR]

Statins, a class of dyslipidemic drugs known as HMG-CoA reductase inhibitors, have emerged as promising compounds for the treatment of chronic heart failure. Nevertheless, the precise mechanism remains to be fully elucidated. Necroptosis is a programmed necrosis-like cell death and has been involved in the development of chronic heart failure. However, it is unclear whether statins exert beneficial effects on therapy for heart failure by inhibiting cardiomyocyte necroptosis. In this study, we administered statins to rats after myocardial infarction and evaluated their effects on the necroptosis pathway in the failing heart following myocardial infarction. Administration of simvastatin or rosuvastatin reduced cardiac dysfunction after myocardial infarction. Concomitantly, the statins prevented the activation of the necroptotic intracellular signaling pathway in myocardial tissue. Simvastatin, but not rosuvastatin treatment attenuated the interaction between Hsp90 and necroptosis-related proteins in myocardial tissue, suggesting that simvastatin prevents necroptosis via Hsp90 inhibition. Necroptosis induced in primary cultured cardiomyocytes isolated from neonatal rats was inhibited by pretreatment with simvastatin. Administration of simvastatin and rosuvastatin inhibited the infiltration of M1 macrophages into myocardial tissue and reduced the myocardial tissue content of tumor necrosis factor-α, an inflammatory cytokine that induces necroptosis, respectively. The findings in the study indicate that statins may prevent necroptosis of cardiomyocytes, attenuating the development of heart failure. However, the present study suggests that the cardioprotective mechanism of simvastatin is not same as that of rosuvastatin., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025. Published by Elsevier Inc.)

Oxidation states and distribution of arsenic (As) in annually laminated (varved) lacustrine deposits were analyzed with a seasonal resolution. This deposit was formed in the mid-Holocene landslide-dammed paleolake in the upper reaches of the Ane River, central Japan and the paleolake watershed consists of the Jurassic accretionary complexes (Mino-Tamba belt) including sedimentary and igneous rocks. In the outcrop, centimeter-to-decimeter-scale silty clay layers alternating with laminated layers are well developed. Bulk concentrations of As in the two layers are 77 ± 27 μg/g on average and mostly occurred in the sulfide fraction (59 % ± 9 %). In the laminated layers, millimeter-scale organic matter (OM)-rich and siderite-rich layers were repeated, indicating deposition during the spring and autumn mixings and the summer stratification, respectively. The OM-rich layers distinctively contain As-rich layers concentrated at the margins of the siderite layers, while they have numerous As-rich hotspots coexisting with S and amorphous OM. Synchrotron-based micro-X-ray absorption near edge structure analysis demonstrated that the As-rich layers contain FeAs -I S, As II S, and As III 2 S 3 at roughly the same levels, whereas FeAs -I S is dominant for the As in hotspots. Based on the results, it is suggested that As accumulation in the varved deposit has been controlled by seasonal changes in OM supply and fluctuation in redox potential with post-depositional degradation of OM., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

A thiosulfate-oxidizing bacterium, Thiomicrospira sp. strain V2501, was isolated from groundwater collected in a terrestrial deep subsurface environment. This strain was capable of chemolithoautotrophic growth on CO 2 and thiosulfate. Here, we report the 2,240,851 bp complete genome sequence of strain V2501., Competing Interests: The authors declare no conflict of interest.