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Oxidative stress is an important mechanism underlying toxicity induced by cadmium (Cd) exposure. However, there are significant differences of the antioxidant baseline in different populations. This means that different human has different intensity of oxidative stress in vivo after exposure to toxicants. LiasH/H mouse is a specific model which is created by genetically modifying the Lias 3′-untranslated region (3′-UTR). LiasH/H mice express high levels of LA and have high endogenous antioxidant capacity which is approximately 150% higher than wild-type C57BL/6 J mice (WT, Lias+/+). But more importantly, they have dual roles of metal chelator and antioxidant. Here, we applied this mouse model to evaluate the effect of endogenous antioxidant levels in the body on alleviating Cd-induced renal injury including Cd metabolism, oxidative stress, and inflammation. In the experiment, mice drank water containing Cd (50 mg/L), for 12 weeks. Many biomarkers of Cd metabolism, oxidative stress, inflammation, and major pathological changes in the kidney were examined. The results showed overexpression of the Lias gene decreased Cd burden in the body of mice, mitigated oxidative stress, attenuated the inflammatory response, and subsequent alleviated cadmium-induced kidney injury in mice. [ABSTRACT FROM AUTHOR]

Oxidative stress and inflammation are mechanisms underlying toxicity induced by fine particulate matter (PM2.5). The antioxidant baseline of the human body modulates the intensity of oxidative stress in vivo. This present study aimed to evaluate the role of endogenous antioxidants in alleviating PM2.5-induced pulmonary injury using a novel mouse model (LiasH/H) with an endogenous antioxidant capacity of approximately 150% of its wild-type counterpart (Lias+/+). LiasH/H and wild-type (Lias+/+) mice were randomly divided into control and PM2.5 exposure groups (n = 10), respectively. Mice in the PM2.5 group and the control group were intratracheally instilled with PM2.5 suspension and saline, respectively, once a day for 7 consecutive days. The metal content, major pathological changes in the lung, and levels of oxidative stress and inflammation biomarkers were examined. The results showed that PM2.5 exposure induced oxidative stress in mice. Overexpression of the Lias gene significantly increased the antioxidant levels and decreased inflammatory responses induced by PM2.5. Further study found that LiasH/H mice exerted their antioxidant function by activating the ROS-p38MAPK-Nrf2 pathway. Therefore, the novel mouse model is useful for the elucidation of the mechanisms of pulmonary injury induced by PM2.5. [ABSTRACT FROM AUTHOR]

The genomic fabric paradigm (GFP) characterizes the transcriptome topology by the transcripts' abundances, the variability of the expression profile, and the inter-coordination of gene expressions in each pathophysiological condition. The expression variability analysis provides an indirect estimate of the cell capability to limit the stochastic fluctuations of the expression levels of key genes, while the expression coordination analysis determines the gene networks in functional pathways. This report illustrates the theoretical bases and the mathematical framework of the GFP with applications to our microarray data from mouse models of post ischemic, and constant and intermittent hypoxia-induced heart failures. GFP analyses revealed the myocardium priorities in keeping the expression of key genes within narrow intervals, determined the statistically significant gene interlinkages, and identified the gene master regulators in the mouse heart left ventricle under normal and ischemic conditions. We quantified the expression regulation, alteration of the expression control, and remodeling of the gene networks caused by the oxygen deprivation and determined the efficacy of the bone marrow mono-nuclear stem cell injections to restore the normal transcriptome. Through the comprehensive assessment of the transcriptome, GFP would pave the way towards the development of personalized gene therapy of cardiac diseases. [ABSTRACT FROM AUTHOR]

Lipoic acid synthetase (LIAS) has been demonstrated to play a crucial role in the progression of cancer. Exploring the underlying mechanisms and biological functions of LIAS could have potential therapeutic guidance for cancer treatment. Our study has explored the expression levels and prognostic values of LIAS in pan-cancer through several bioinformatics platforms, including TIMER2.0, Gene Expression Profiling Interactive Analysis, version 2 (GEPIA2.0), and Human Protein Atlas (HPA). We found that a high LIAS expression was related to the good prognosis in patients with kidney renal clear cell carcinoma (KIRC), rectum adenocarcinoma (READ), breast cancer, and ovarian cancer. Inversely, a high LIAS expression showed unfavorable prognosis in lung cancer patients. In addition, the genetic alteration, methylation levels, and immune analysis of LIAS in pan-cancer have been evaluated. To elucidate the underlying molecular mechanism of LIAS, we conduct the single-cell sequencing to implicate that LIAS expression was related to hypoxia, angiogenesis, and DNA repair. Thus, these comprehensive pan-cancer analyses have conveyed that LIAS could be potentially significant in the progression of various cancers. Moreover, the LIAS expression could predict the efficacy of immunotherapy in cancer patients. [ABSTRACT FROM AUTHOR]

Objective: The aim of the present study is to evaluate a neurocognitive outcome in patients affected by late-onset idiopathic aqueductal stenosis (LIAS) who underwent endoscopic third ventriculostomy (ETV). Materials and Methods: A prospective study was conducted between January 2015 and December 2017 in a series of 10 consecutive adult patients referred to the Neurosurgery Department of IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy. All the adult patients admitted with absence of CSF flow through the aqueduct in phase-contrast (PC)—MRI sequences or a turbulence void signal in T2—weighted images in midsagittal thin-slice MR sequences underwent a specific neuroradiological, neurological, and neurocognitive assessment pre- and postoperatively. Results: All patients affected by gait and sphincter disturbances improved after ETV. Attentive and executive functions as well as visuo-spatial memory and verbal executive functions improved in several patients. Similarly, the affective and behavioral scales improved in almost 50% of the patients. No major complications have been recorded, and no patients required a second surgery for shunt placement. Conclusion: Endoscopic third ventriculostomy represents a safe and effective surgical procedure for the treatment of LIAS. In addition to neurological improvement, we demonstrated also postoperative neurocognitive improvement mainly in attentive and executive functions, visuo-spatial memory, verbal executive functions, and behavioral and affective domains. [ABSTRACT FROM AUTHOR]

ObjectiveThe aim of the present study is to evaluate a neurocognitive outcome in patients affected by late-onset idiopathic aqueductal stenosis (LIAS) who underwent endoscopic third ventriculostomy (ETV).Materials and MethodsA prospective study was conducted between January 2015 and December 2017 in a series of 10 consecutive adult patients referred to the Neurosurgery Department of IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy. All the adult patients admitted with absence of CSF flow through the aqueduct in phase-contrast (PC)—MRI sequences or a turbulence void signal in T2—weighted images in midsagittal thin-slice MR sequences underwent a specific neuroradiological, neurological, and neurocognitive assessment pre- and postoperatively.ResultsAll patients affected by gait and sphincter disturbances improved after ETV. Attentive and executive functions as well as visuo-spatial memory and verbal executive functions improved in several patients. Similarly, the affective and behavioral scales improved in almost 50% of the patients. No major complications have been recorded, and no patients required a second surgery for shunt placement.ConclusionEndoscopic third ventriculostomy represents a safe and effective surgical procedure for the treatment of LIAS. In addition to neurological improvement, we demonstrated also postoperative neurocognitive improvement mainly in attentive and executive functions, visuo-spatial memory, verbal executive functions, and behavioral and affective domains.

Worldwide, lung cancer is a leading cause of cancer-related deaths and is the most commonly diagnosed form of cancer. A major characteristic of lung cancer is its profound clinical, histological and molecular heterogeneity. This heterogeneity is not only spatial but also temporal thus stressing the need for personalized patient-tailored treatment planning. The current optimal treatment planning is currently based on real-time monitoring of the evolving molecular profiling of the tumour throughout the course of the disease and treatment. In the current work, we will investigate the emerging role that that RPL9 and LIAS could have in carcinogenesis. While the aberrant expression of RPL9 has already been shown to occur in colorectal cancer its role in lung cancer is not yet known. In a similar manner, the role of LIAS, as a metabolism-linked gene, in cancer biology and especially in lung cancer is still unknown. Emerging research reveals both RPL9 and LIAS as interacting partners and apoptosis resistance genes. The aim of this study is to determine the differential expression of the rpl9 and lias genes in both normal lung tissue and lung cancer samples. This was achieved by using in situ hybridization (ISH) and quantitative Real-time PCR (qPCR). Further data on the role played by RPL9 in lung cancer was established through the use of in silico bioinformatic analysis. This was done in order to map biological pathways enriched by the expression of these genes. Both the KEGG pathway and Reactome analysis confirmed the role of these genes in RNA metabolic pathways. Furthermore, RPL9 was shown to play a role in signal transduction, autophagy, and cellular response to stress pathways. The function of these two proteins overlapped with regard to protein metabolism. STRING analysis also demonstrated an interaction between RPL9 and LIAS. Here we propose that the aberrant expression of RPL9 and LIAS may contribute to lung carcinogenesis and can be targeted for molecular therapy.

Three human mitochondrial diseases that directly affect lipoic acid metabolism result from heterozygous missense and nonsense mutations in the LIAS , LIPT1 , and LIPT2 genes. However, the functions of the proteins encoded by these genes in lipoic acid metabolism remained uncertain due to a lack of biochemical analysis at the enzyme level. An exception was the LIPT1 protein for which a perplexing property had been reported, a ligase lacking the ability to activate its substrate. This led to several models, some contradictory, to accommodate the role of LIPT1 protein activity in explaining the phenotypes of the afflicted neonatal patients. Recent evidence indicates that this LIPT1 protein activity is a misleading evolutionary artifact and that the physiological role of LIPT1 is in transfer of lipoic acid moieties from one protein to another. This and other new biochemical data now define a straightforward pathway that fully explains each of the human disorders specific to the assembly of lipoic acid on its cognate enzyme proteins. [ABSTRACT FROM AUTHOR]

Background: Nonketotic hyperglycinemia (NKH) is a rare metabolic disorder that is characterized by high levels of glycine in plasma and cerebrospinal fluid in humans. In this study, total congenital cataract captive‐bred Vervet monkeys (Chlorocebus aethiops) that are hyperglycinemic were screened to identify mutations in Bola type 3 (BOLA3), glutaredoxin 5 (GLRX5), and lipoate synthase (LIAS) genes. Methods: Twenty‐four Vervet monkeys (12 hyperglycinemic and 12 healthy controls) were selected for mutation analysis using polymerase chain reaction (PCR), Sanger sequencing, and reverse transcriptase‐polymerase chain reaction (RT‐PCR). Results: Novel sequence variants were identified in BOLA3 (R23H and Q38R) and LIAS (R369I and A371A), and gene expression in the control group was significantly lower compared to the hyperglycinemic group (P < 0.05). Conclusion: The data obtained from this study will contribute to generation of new knowledge regarding the involvement of these genes in NKH development. [ABSTRACT FROM AUTHOR]

Ferredoxins are a family of iron-sulfur (Fe-S) cluster proteins that serve as essential electron donors in numerous cellular processes that are conserved through evolution. The promiscuous nature of ferredoxins as electron donors enables them to participate in many metabolic processes including steroid, heme, vitamin D, and Fe-S cluster biosynthesis in different organisms. However, the unique natural function(s) of each of the two human ferredoxins (FDX1 and FDX2) are still poorly characterized. We recently reported that FDX1 is both a crucial regulator of copper ionophore-induced cell death and serves as an upstream regulator of cellular protein lipoylation, a mitochondrial lipid-based post-translational modification naturally occurring on four mitochondrial enzymes that are crucial for TCA cycle function. Here we show that FDX1 directly regulates protein lipoylation by binding the lipoyl synthase (LIAS) enzyme promoting its functional binding to the lipoyl carrier protein GCSH and not through indirect regulation of cellular Fe-S cluster biosynthesis. Metabolite profiling revealed that the predominant cellular metabolic outcome of FDX1 loss of function is manifested through the regulation of the four lipoylation-dependent enzymes ultimately resulting in loss of cellular respiration and sensitivity to mild glucose starvation. Transcriptional profiling established that FDX1 loss-of-function results in the induction of both compensatory metabolism-related genes and the integrated stress response, consistent with our findings that FDX1 loss-of-function is conditionally lethal. Together, our findings establish that FDX1 directly engages with LIAS, promoting its role in cellular protein lipoylation, a process essential in maintaining cell viability under low glucose conditions., Competing Interests: Conflict of interest P. T. was a consultant and has received research funding from Riva Therapeutics., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

The petroleum system of the Upper Rhine Graben (URG) comprises multiple reservoir rocks and four major oil families, which are represented by four distinct source rock intervals. Based on geochemical analyses of new oil samples and as a review of chemical parameter of former oil fields, numerous new oil-source rock correlations were obtained. The asymmetric graben resulted in complex migration pathways with several mixed oils as well as migration from source rocks into significantly older stratigraphic units. Oldest oils originated from Liassic black shales with the Posidonia Shale as main source rock (oil family C). Bituminous shales of the Arietenkalk-Fm. (Lias α) show also significant source rock potential representing the second major source rock interval of the Liassic sequence. Within the Tertiary sequence several source rock intervals occur. Early Tertiary coaly shales generated high wax oils that accumulated in several Tertiary as well as Mesozoic reservoirs (oil family B). The Rupelian Fish Shale acted as important source rock, especially in the northern URG (oil family D). Furthermore, early mature oils from the evaporitic-salinar Corbicula- and Lower Hydrobienschichten occur especially in the area of the Heidelberg-Mannheim-Graben (oil family A). An overview on potential source rocks in the URG is presented including the first detailed geochemical source rock characterization of Middle Eocene sediments (equivalents to the Bouxwiller-Fm.). At the base of this formation a partly very prominent sapropelic coal layer or coaly shale occurs. TOC values of 20-32 % (cuttings) and Hydrogen Index (HI) values up to 640-760 mg HC/g TOC indicate an extraordinary high source rock potential, but a highly variable lateral distribution in terms of thickness and source rock facies is also supposed. First bulk kinetic data of the sapropelic Middle Eocene coal and a coaly layer of the 'Lymnäenmergel' are presented and indicate oil-prone organic matter characterized by low activation energies. These sediments are considered as most important source rocks of numerous high wax oils (oil family B) in addition to the coaly source rocks from the (Lower) Pechelbronn-Schichten (Late Eocene). Migration pathways are significantly influenced by the early graben evolution. A major erosion period occurred during the latest Cretaceous. The uplift center was located in the northern URG area, resulting in SSE dipping Mesozoic strata in the central URG. During Middle Eocene times a second uplift center in the Eifel area resulted in SW-NE-directed shore lines in the central URG and contemporaneous south-southeastern depocenters during marine transgression from the south. This structural setting resulted in a major NNW-NW-directed and topography-driven migration pattern for expelled Liassic oil in the fractured Mesozoic subcrop below sealing Dogger α clays and basal Tertiary marls. [ABSTRACT FROM AUTHOR]

The Blue Lias Formation at Lyme Regis (Dorset, UK) includes an exceptional pavement of abundant large ammonites that accumulated during a period of profound sedimentary condensation. Ammonites were originally composed of aragonite, an unstable polymorph of calcium carbonate, and such fossils are typically prone to dissolution; the occurrence of a rich association of aragonitic shells in a condensed bed is highly unusual. Aragonite dissolution occurs when pore-water p H is reduced by the oxidization of hydrogen sulphide close to the sediment-water interface. Evidence suggests that, in this case, the oxygen concentrations in the overlying water column were low during deposition. This inhibited the oxidation of sulphides and the associated lowering of p H, allowing aragonite to survive long enough for the shell to be neomorphosed to calcite. The loss of aragonite impacts upon estimates of past biodiversity and carbonate accumulation rates. The preservational model presented here implies that diagenetic loss of aragonite will be greatest in those areas where dysoxic-anoxic sediment lies beneath an oxic waterbody but least where the sediment and overlying water are oxygen depleted. Unfortunately, this implies that preservational bias through aragonite loss will be greatest in those biotopes which are typically most diverse and least where biodiversity is lowest due to oxygen restriction. [ABSTRACT FROM AUTHOR]

Even after 200 years of study, some details of the cranial anatomy of ichthyosaurs, one of the most successful groups of marine vertebrates in the Mesozoic, are still unclear. New information on the braincase, palate and occiput are provided from three-dimensional scans of an exceptionally preserved ichthyosaur (' Hauffiopteryx' typicus) skull from the Toarcian (183-174 Ma, Lower Jurassic) of Strawberry Bank, England. This ichthyosaur has unusual, hollow, tubular hyoid bars. The occipital and braincase region is fully reconstructed, creating the first digital cranial endocast of an ichthyosaur. Enlarged optic lobes and an enlarged cerebellum suggest neuroanatomical adaptations that allowed it to be a highly mobile, visual predator. The olfactory region also appears to be enlarged, suggesting that olfaction was more important for ichthyosaurs than has been assumed. Phylogenetic analysis suggests this ichthyosaur is closely related to, but distinct from, Hauffiopteryx, and positioned within Thunnosauria, a more derived position than previously recovered. These results further our knowledge of ichthyosaur cranial anatomy in three dimensions and provide a platform in which to study the anatomical adaptations that allowed ichthyosaurs to dominate the marine realm during the Mesozoic. [ABSTRACT FROM AUTHOR]

En el presente trabajo se estudia por técnicas petrográficas y mediante ensayos de pirólisis o técnicas geoquímicas la serie marina del borde Oeste de la Playa de Peñarrubia (Asturias) para conocer la naturaleza de su parte orgánica. Las observaciones microscópicas en luz blanca y por fluorescencia han permitido establecer una clasificación general de la materia orgánica dispersa, su distribución y concentración a lo largo de toda la serie y según las diferentes litologías. Se han clasificado los componentes orgánicos en 9 grupos mayoritarios que se concentran, principalmente en los niveles margosos y lutíticos del Pliensbachiense, habiéndose delimitado niveles bituminosos en la parte superior de la serie. Estos están constituidos por un kerógeno de tipo 11 mixto formado por un material autóctono derivado del zooplancton y fitoplancton con escasos aportes de origen continental. El rango de la MOD ha sido determinado por reflectividad de la huminita y Rock-Eval (Tmax). La materia orgánica está en estadio inmaduro, antes de la ventana de generación del petróleo. Los ensayos de pirólisis han permitido obtener rendimientos en aceite observándose que los más elevados han correspondido a los niveles de mayor contenido orgánico o niveles bituminosos. La correlación entre los datos petrográficos y los de carácter geoquímico indica que existe una buena concordancia entre los mismos, habiéndose determinado que los componentes que generan principalmente el aceite por pirólisis a los 500°C son los más hidrogenados. Estos corresponden a las algas, fibras y matriz órgano-mineral además de otras asociaciones submicroscópicas.

Lipoic acid synthetase (LIAS) has been demonstrated to play a crucial role in the progression of cancer. Exploring the underlying mechanisms and biological functions of LIAS could have potential therapeutic guidance for cancer treatment. Our study has explored the expression levels and prognostic values of LIAS in pan-cancer through several bioinformatics platforms, including TIMER2.0, Gene Expression Profiling Interactive Analysis, version 2 (GEPIA2.0), and Human Protein Atlas (HPA). We found that a high LIAS expression was related to the good prognosis in patients with kidney renal clear cell carcinoma (KIRC), rectum adenocarcinoma (READ), breast cancer, and ovarian cancer. Inversely, a high LIAS expression showed unfavorable prognosis in lung cancer patients. In addition, the genetic alteration, methylation levels, and immune analysis of LIAS in pan-cancer have been evaluated. To elucidate the underlying molecular mechanism of LIAS, we conduct the single-cell sequencing to implicate that LIAS expression was related to hypoxia, angiogenesis, and DNA repair. Thus, these comprehensive pan-cancer analyses have conveyed that LIAS could be potentially significant in the progression of various cancers. Moreover, the LIAS expression could predict the efficacy of immunotherapy in cancer patients., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Cai, He, Liu, Liang, Peng, Li, Zhang, Kang, Hong, Yan, Peng, Xu and Bai.)

Abstract: Trace elements and rare earth elements (REEs) of Lias-aged cherts in the Gumushane area were studied in order to understand their origin and depositional environment. Twenty three chert samples from five stratigraphic sections were analysed by inductively coupled plasma-mass spectrometry, X-ray diffraction, and mineralogical investigation. Lias cherts in the study area are microcrystalline, cryptocrystalline quartz, and megaquartz depending on mineralogical content. Trace elements of the cherts were compared with PAAS, Co, Y, and Th had stronger depletions in the five sections, whereas V, Ni, Zr, Nb, and Hf had smaller depletions. The distribution of Zr, Hf, and Ta yields Zr/Hf, Zr/Ta and Hf/Ta ratios (25/645, 37/665, and 0.18/3, respectively) that differ from those of chondrites and average upper continental crust, suggesting that these elements are likely non-detrital but are sourced from seawater. Th/U ratios range from 0.04 to 0.45 and are lower than those of the upper continental crust (average: 3.9). Lias-aged cherts have low total REE abundances and stronger depletions in five sections of the PAAS and chondrite-normalised plots. The cherts are characterised by a positive Eu anomaly (average: 4.9) and LREE-enrichment (LaN/YbN =average: 3.5). In addition, about one-half of the cherts exhibit positive Ce anomaly (range: 0.25–2.58), chondritic Y/Ho values (range: 3.3–60), and low (La/Ce)N values (average: 1.8). REE and trace element abundance in Lias cherts indicate that these elements were likely derived from hydrothermal solutions, terrigenous sources, and seawater. The REE patterns of the cherts show that they were probably deposited close to a continental margin. [Copyright &y& Elsevier]

An incomplete skull of the leptonectid ichthyosaur Eurhinosaurus longirostris found in the Rietheim Member (previously 'Posidonienschiefer'; Toarcian, Early Jurassic) of Staffelegg, Canton Aargau, is the first record from Switzerland of this taxon and supports the status of Eurhinosaurus longirostris as a palaeobiogeographic very widespread ichthyosaur species in the Early Toarcian of Western Europe. Being from either the Bifrons or Variabilis zone, it is one of the youngest records of Eurhinosaurus and one of the few diagnostic ichthyosaur finds from this time interval. The partial skull is well articulated and preserved three-dimensionally in a carbonate concretion. Both the mode of preservation of the ichthyosaur and an associated ammonoid ( Catacoeloceras raquinianum) provided the age of the concretion, which had been collected from scree. Taphocoenosis and taphonomy show the C. raquinianum to be one of few non re-worked fossils recorded from the Early to Late Toarcian boundary (Bifrons/Variabilis zone) of northern Switzerland in general and of this ammonite species in particular. The Toarcian section at Staffelegg differs from other localities where strata of the same age are exposed with respect to facies variations of the Rietheim Member (previously 'Posidonienschiefer', Early Toarcian) and the extraordinarily high thickness of the Gross Wolf Member (previously 'Jurensis-Mergel', Late Toarcian). [ABSTRACT FROM AUTHOR]

The deposits of the Early Jurassic in northern Switzerland accumulated in the relatively slowly subsiding transition zone between the southwestern part of the Swabian basin and the eastern part of the Paris basin under fully marine conditions. Terrigenous fine-grained deposits dominate, but calcarenitic and phosphorit-rich strata are intercalated. The total thickness varies between 25 and 50 m. In the eastern and central parts of N Switzerland, sediments Sinemurian in age constitute about 90% of the total thickness. To the West, however, in the Mont Terri area, Pliensbachian and Toarcian deposits form 70% of the total thickness. Stratigraphic gaps occur on a local to regional scale throughout N Switzerland. Such hiatus comprise a subzone to a stage in time. With respect to lithology and fossil content, the Early Jurassic deposits in northern Switzerland are similar to those in SW Germany. Nonetheless, an exact stratigraphic correlation is hardly possible, particulary in the southern and southwestern Folded Jura where distinct facies changes occur over short distances. Revised existing and new litho- and biostratigraphic data form the base to refine the stratigraphic subdivision of the deposits that have been informally called 'Lias'. The name Staffelegg Formation is suggested and defined as the mapping unit for the Early Jurassic. The Staffelegg Formation is introduced for Early Jurassic sediments in northern Switzerland between the Doubs River and Mt. Weissenstein in the west and the Randen Hills located north of the city of Schaffhausen in the east. The Staffelegg Formation starts within the Planorbis zone of the Hettangian. The upper boundary to the overlying Aalenian Opalinus-Ton is diachronous. The lithostratigraphic names previously in use have been replaced by new ones, in accordance within the rules of lithostratigraphic nomenclature. The Staffelegg Formation comprises 11 members and 9 beds. Several of these beds are important correlation horizons in terms of allostratigraphy. Some of them correspond to strata or erosional unconformities encountered in the Swabian realm, some of them can be correlated with strata in the Paris basin. The facies transition to the Paris basin is expressed by introduction of a corresponding lithostratigraphic unit. [ABSTRACT FROM AUTHOR]

Abstract: A geoelectrical investigation of a slow moving earth slide–earth flow in Lower Jurassic Lias Group rocks of the Cleveland Basin, UK, is described. These mudrock slopes are particularly prone to failure and are a major source of lowland landslides in the UK, but few attempts have been made to spatially or volumetrically characterise the subsurface form of these slides. The primary aim of this study was to consider the efficacy of fully three-dimensional geoelectrical imaging for landslide investigation with reference to a geological setting typical of Lias Group escarpments. The approach described here included a reconnaissance survey phase using two-dimensional electrical resistivity tomography (ERT), resistivity mapping, self-potential (SP) profiling and mapping, followed by a detailed investigation of an area of the landslide using three-dimensional (3D) ERT and self-potential tomography (SPT). Interpretation of the geophysical data sets was supported by surface observations (aerial LiDAR and differential GPS geomorphological surveys) and intrusive investigations (boreholes and auger holes). The initial phase of the study revealed the existence of a strong SP signature at the site consistent with a streaming potential source and established the relationships between the main geological units, the geomorphologic expression of the landslide, and the resistivity of the materials in and around the study area. The 3D SPT model generated during the second phase of the study indicated drainage patterns across the landslide and preferential flow from the low permeability mud rocks into the underlying more permeable sandstone formation. Because of favourable resistivity contrasts between the clay-rich Whitby Mudstone Formation landslide material and the underlying Staithes Sandstone Formation, the volumetric 3D ERT image allowed a number of surface and subsurface landslide features to be identified and spatially located. These included the lateral extent of slipped material and zones of depletion and accumulation; the surface of separation and the thickness of individual earth flow lobes; and the dipping in situ geological boundary between the Whitby Mudstone and Staithes Sandstone bedrock formations. [Copyright &y& Elsevier]

In the Causses platform (south-east France), Late Hettangian to Sinemurian deposits were interpreted previously as shallow-water carbonate ramp deposits. A new look at these deposits has shown a fault-controlled mosaic carbonate platform that is different from the carbonate ramp models. Within the platform mosaic, 15 lithofacies have been recognized, which are organized in four facies associations, including peritidal, restricted shallow sub-tidal, sand dunes and sub-tidal shelf facies associations. The rapid lateral and vertical facies changes, and the lack of consistent landward or seaward direction indicated by the pattern of facies changes, question the existence of a shoreline suggested by the traditional models for this region. Instead, the facies organization and cycle stacking pattern suggest deposition in a mosaic of intertidal islands between which sub-tidal restricted or open conditions could coexist in very close proximity. Such a platform mosaic would have been defined by tectonic activities along normal faults which segmented the shallow-water Causses platform. The facies and facies associations are arranged into metre-scale, peritidal and sub-tidal cycles that are also variable. Certain cycles show the same stacking pattern in all the sections and seem to be traceable over tens of kilometres. On the contrary, other cycles cannot be correlated; they are present only in specific sections and have a maximum lateral extension of 1 or 2 km. These metre-scale cycles stack to form four medium-scale cycles bounded by surfaces that display sub-aerial exposure features. Medium-scale cycles stack into two larger-scale cycles (tens of metres thick) and are bounded by well-defined karstic surfaces. Based on their lateral continuity and their stacking pattern, the metre-scale cycles are controlled probably by high frequency eustatic variations overprinting the topographic irregularities formed by differential subsidence of fault-bounded blocks. Episodic fault activities may reorganize the topography so that, even if eustatic changes may still be the major control of cycles, the expression and number of cycles could be different. Cycles of medium and large-scale are interpreted as being allogenic, controlled by changes in eustasy and/or subsidence rates as evidenced by their lateral continuity and the correlations of the large-scale cycles with third-order depositional sequences. [ABSTRACT FROM AUTHOR]

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Processing of gravity and magnetic maps shows that the basement of the Upper Rhine Graben area is characterized by a series of NE–SW trending discontinuities and elongated structures, identified in outcrops in the Vosges, Black Forest, and the Odenwald Mountains. They form a 40 km wide, N30–40° striking, sinistral wrench-zone that, in the Visean, shifted the Variscan and pre-Variscan structures by at least 43 km to the NE. Wrenching was associated with emplacement of several generations of plutonic bodies emplaced in the time range 340–325 Ma. The sub-vertical, NE–SW trending discontinuities in the basement acted as zones of weakness, susceptible to reactivation by subsequent tectonism. The first reactivation, marked by mineralizations and palaeomagnetic overprinting along NE–SW faults of the Vosges Mountains, results from the Liassic NW–SE extension contemporaneous with the break-up of Pangea. The major reactivation occurred during the Late Eocene N–S compression and the Early-Middle Oligocene E–W extension. The NE–SW striking basement discontinuities were successively reactivated as sinistral strike-slip faults, and as oblique normal faults. Elongated depocenters appear to form in association with reactivated Variscan wrench faults. Some of the recent earthquakes are located on NE–SW striking Variscan fault zones, and show sinistral strike-slip focal mechanisms with the same direction, suggesting also present reactivation. [ABSTRACT FROM AUTHOR]

Abstract: The Lias and Dogger series in the southern Paris Basin outcrops are precisely dated following the ammonite biozonation scale. In these series, the depositional environment context is accurately identified and thus various isopic zones can bee recognized. From the outcrop study, the depositional sequence and the tectonics events are also distinguished. The poorly dated subsurface data should be not anymore interpreted as diagraphic signatures, with the traditional peak to peak correlation. They now need to be analysed according to the geodynamic evolution of each isopic zone. The Liassic transgressive series (in the Armorican continent) and the Dogger platforms numerous carbonate bodies are correlated at biostratigraphic scale, throughout the whole southern Paris Basin. Subsequently, paleogeographic maps are established and based on depositional sequences. The basin evolution image changes radically. This shows clearly that the complexes carbonate bodies layout prohibits any depositional environment interpretation and any isopach mapping at geological stage level. If not, the carbonate platforms of different age would be amalgamated, without any connection with the reality. Over the time, paleogeographic maps show syn-sedimentary short wavelength deformations, more or less well expressed according to the local sedimentary context. During the Lias and the Dogger, three steps can be distinguished in the southern Paris Basin. Hettangian to Lower Aalenian, the progressive increase in accommodation drives to total immersion of the continental areas; the maximum of accommodation during the Middle Toarcian entails uniform sedimentary conditions. However, short wavelength deformations persist. The major accidents defining the isopic zones are mainly North-South oriented. Middle Aalenian to Middle Bathonian, isopic zones are contrasted, controlled by the North-South accidents but also the North West-South East ones ; the variable accommodation allowed the development of regional sedimentary gaps and shallow limestone progradations on a marly area (so called “Sillon marneux”) ; tectonics events correspond to the Tethyan and the North Sea riftings influences. Upper Bathonian to Upper Oxfordian, the North West-South East tectonics accidents are particularly active; this tectonic phase could be associated to the thermal event, described in the Paris Basin and announcing the Malm depositional environment. [Copyright &y& Elsevier]

Abstract: A three-dimensional well-preserved ichthyosaur skull and parts of the postcranial skeleton are attributed to the species Leptonectes tenuirostris (Conybeare, 1822). It was found vertically embedded in Pliensbachian deposits representing three successive biozones (ibex to margaritatus Zone). The find is dated as early Late Pliensbachian (margaritatus Zone) by a rich ammonite and ostracod fauna. It is the first record of the genus Leptonectes from Switzerland and from the Late Pliensbachian. It is so far the best preserved and most complete ichthyosaur from this time interval worldwide. With diagnostic specimens known from the Rhaetian (Late Keuper) up to the early Late Pliensbachian (Middle Liassic), L. tenuirostris (Conybeare, 1822) has the most extensive stratigraphic range documented for any post-Triassic ichthyosaur so far. [Copyright &y& Elsevier]

Micritic limestones form part of cyclic alternations of limestones- marls/shales in many offshore facies of epeiric seas and their origin has been, and still is, subject to controversy. As an example from the offshore ramp facies, the origin of Lower Lias micritic limestones of SW Britain has been investigated. The very continuous limestone beds show many petrographic and geochemical similarities to isolated nodules, which occur within the marls and are interpreted as being of diagenetic origin. Displacive growth of the microspar crystals was the most important process that occurred during the near-surface formation of the central part of limestone beds, but their edges formed during later burial. The carbon isotopic values (+1.1‰ to −3.4‰ (PDB)) of the central part of the limestone beds and nodules suggest a predominantly marine source for the carbonate, whereas bacterial sulphate reduction played a minor part in their cementation. The oxygen isotopic values (−1.5‰ to −7.2‰ (PDB)) of the characteristic limestone beds, and nodules suggest their formation (cementation/recrystallization) commenced at shallow depth but continued during progressive burial. The microspar crystals of the matrix of the limestones show rare aragonitic relics or pitted surface. Aragonitic fossil remains are rare in these offshore facies and this is in contrast to their abundance in the laterally equivalent shallow marine facies (Sutton Stone). It is suggested that early submarine dissolution of aragonitic components (lime mud and bioclasts) was important in providing carbonate for cementation of the limestones. Early submarine dissolution may have been a common process in epicontinental epeiric settings with low deposition rates, and as the result long residence time in the early diagenetic zones. [ABSTRACT FROM AUTHOR]

Abstract: The Lias–Dogger successions of the Tariquide units in the Gibraltar Arc differ from the series of tectonically adjacent units, the Penibetic (Iberia margin) and the Limestone ‘Dorsale’ (Alboran Domain). Lower Lias limestones are eroded and covered by the Domerian, which starts by deposits of open sea, continuous up to the Dogger (J. Musa-type successions), and elsewhere (Los Pastores-type successions) by a thin series (Upper Lias to Upper Dogger), starting by a manganesiferous episode (Ras Leona) and including marls deposited into three episodes, dated by calcareous nannofossils. Faulting events occurred before the Domerian and during the Late Toarcian (Los Pastores). To cite this article: M. Durand-Delga et al., C. R. Geoscience 337 (2005). [Copyright &y& Elsevier]

Dolomitization is the most significant diagenetic process within the Liassic carbonates of the Tazekka district. It is more extensive in the Middle Atlas Causse than in the Middle Atlas domain.In the Middle Atlas Causse, the dolomites may be syndepositional, early diagenetic, epigenetic (with a paleogeographical control), or hydrothermal. Three hydrothermal dolomites are associated with the ore deposits. Two early phases, type 1 and 2, are separated in time from a phase of saddle dolomite. Saddle dolomite represents a late stage diagenesis post-dating Pb–Zn mineralization. Early dolomites and saddle dolomite were precipitated from similar fluids during three distinct phases but formed by two mechanisms, by a continuum of replacement during Carixian (early hydrothermal type 1 dolomite) and the Toarcian (early hydrothermal type 2 dolomite) and by cement precipitation (saddle dolomite). Precipitation of saddle dolomite cement followed a phase of fracture generation.In the Middle Atlas the sequential character of changes in dolomite characteristics in the middle formation of the Lower Lias confirms the synsedimentary nature of early diagenesis and seawater is regarded as the source of the Mg. Euhedral dolomite crystals indicate a minor late diagenesis.The δ13C values of the dolomites range from −0.83‰ to +2.37‰ PDB. There is a general decrease in δ18O values and a corresponding increase in diagenetic intensity from the laminated dolomite (−2.43‰) to the dolomitized calcarenite at the base of reduced series of the Middle Lias (−9.77‰).There is a decrease in both δ18O and δ13C values in the ore deposits passing from sterile to mineralized rocks. Mineralized limestones show δ18O values of around −7.66‰. The dolomites of Bou Khalifa average −7.20‰, those of Aı¨n Hallouf −7.96‰, Asdi Ben Zerhla −7.86‰ and Aı¨n Tarselt −8.21‰ have similar average values, but those of Sidi Abdellah have values of around −9.79‰. δ18O values of the hydrothermal dolomites differentiate two groups: the first contains the stratiform ore deposits and the second the orebody of Sidi Abdellah. Saddle dolomites have an average δ18O values of −9.39‰ PDB. These phases possess differing isotopic signatures and apparently formed at different temperatures.Several different waters were involved in the formation of the dolomites of the Tazekka district and that contrasting processes were involved in these episodes of dolomitization. [Copyright &y& Elsevier]

When English marine Reptiles crossed the Channel. Mary Anning and Georges Cuvier, two actors of the discovery and study of Ichthyosaurs and Plesiosaurs. From 1800 to 1824, Georges Cuvier succeeded in obtaining a great deal of informations, as well as documents, drawings, casts and original fossils related to marine Reptiles (Ichthyosaurs and Plesiosaurs) from the Lower Jurassic (Lias) of Great Britain. He was completely informed about the discoveries made by Mary Anning. A great number of documents in the archives of the Museum national d’histoire naturelle in Paris show the importance and the quality of the scientific links that existed between France and Great Britain, in spite of the political vicissitudes between the two nations. [Copyright &y& Elsevier]