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Previous stable oxygen isotope records of calcitic fossils (δ18Oshell) from Europe have been interpreted to reflect strong climatic perturbations throughout the Jurassic, but it is unknown whether they reflect global trends because data from other regions are sparse. Here, we use bivalve and brachiopod shells from western Asia and northern Africa to examine seawater temperatures at low latitudes as well as latitudinal temperature gradients in the Middle Jurassic. Our results include the first absolute temperature estimates for most of the study areas and this time interval. Furthermore, we acknowledge a latitudinal gradient in δ18O values of seawater (δ18Osea) that leads to more realistic temperature reconstructions of tropical water temperatures, which were underestimated by earlier methods. Following this approach, δ18Oshell values translate into average equatorial water temperatures during the Middle Jurassic several degrees higher than today (as high as 34–35 °C). Such high temperatures cause environmental stress, probably explaining previously documented low diversities of low-latitudinal ecosystems (e.g., coral reefs) during this time interval. A comparison with literature data raises doubts over whether previously published European temperature curves are truly representative of global patterns. Instead, they might reflect the complex paleogeography of European basins influenced by regional and/or short-term changes in δ18Osea values.

Introduction Autosomal dominant polycystic kidney disease (ADPKD) is characterized by progressive cyst enlargement, leading to kidney failure. Sirtuin-1 is upregulated in ADPKD and accelerates disease progression by deacetylating p53. Niacinamide is a dietary supplement that inhibits sirtuins at high doses. Methods We conducted an open-label, single-arm intervention trial (study 1, N = 10), and a randomized, double blinded, placebo-controlled trial (study 2, N = 36) to assess the biological activity and safety of niacinamide. Patients with ADPKD were given 30 mg/kg oral niacinamide or placebo, for 12 months. The primary endpoint was the ratio of acetylated p53 to total p53 protein in peripheral blood mononuclear cells (PBMCs). Results There was no sustained effect of niacinamide on acetylated/total p53 in either study and no difference between placebo and niacinamide arms. There was no difference in the change in height-adjusted total kidney volume over 12 months between niacinamide and placebo. Niacinamide was generally well tolerated. The most common adverse effects were nausea, diarrhea, gastroesophageal reflux, headache, and acneiform rash but there was no difference in their incidence between niacinamide and placebo. Conclusions In conclusion, niacinamide is safe and well-tolerated in patients with ADPKD. However, we were unable to detect a sustained inhibition of sirtuin activity over 12 months of treatment, and there was no signal to suggest a beneficial effect on any efficacy measure., Graphical abstract

Middle to Late Jurassic belemnites from the Spiti and Zanskar valleys in the Indian Himalayas were used for stable isotope (δ13C, δ18O) and element (Mg/Ca, Sr/Ca) analyses. Although the Himalayan orogeny deformed and altered a large portion of the collected fossils, cathodoluminescence and scanning electron microscopy in combination with analyses of iron and manganese contents allowed the identification of belemnites believed to still retain their original chemical composition. Results indicate a long-term temperature decrease from the Middle Callovian–Oxfordian to the Tithonian, which is proposed to have been caused by a concomitant drift of eastern Gondwana into higher palaeolatitudes. Reconstructed absolute temperatures depend on the used equation and assumed δ18O value of seawater, but most likely varied between 17.6 °C to 27.6 °C in the Kimmeridgian and Tithonian with average values between 22 °C to 24 °C. This way, temperatures were similar to slightly warmer than today at comparable latitudes. The reconstruction of absolute temperatures for the Middle Callovian–Oxfordian was hindered by a larger number of poorly preserved belemnites representing this time interval.

Soil moisture (q) is a key variable for agriculture, however a gap remains in observations at intermediate scales, the cosmic-ray neutron sensor (CRNS) is a novel tool for such applications. We designed an experiment using a CRNS and time domain reflectometry (TDR at vegetated and bare soil sites) to measure q in the Yaqui Valley, where wheat (Triticum spp) is the main crop and water is managed by flooded irrigation. We used a drydown analysis of the daily rate at which q is lost (qdecay) after every irrigation, and the amount of q that represents 1/3 of the remaining q as soil dries (qthreshold). Statistical analysis included multivariate correlations (Spearman) and a principal components analysis (PCA) using q , meteorological variables, and vegetation greenness. With TDR’s we observed differences in qdecay, it was higher at the vegetation site qdecay= 0.53 cm3/cm3 /day, while qthreshold was higher at bare soil site 0.33 cm3/cm3. The qdecay observed with the CRNS was higher for the 2nd and 3rd irrigation (0.7 cm3/cm3 /day and 0.16 cm3/cm3 /day, respectively). After each irrigation, the meteorological variables correlated with q varied, highlighting air temperature (Tair, r=-0.7) in the 1st irrigation, evapotranspiration (ET, r>0.5) and vapor pressure deficit (VPD, r=0.6, r=-0.8) for the 2nd and 3rd irrigation, and normalized difference vegetation index (NDVI, r=0.8) for the 3rd irrigation. The variation explained by PC1 and PC2 increases with each irrigation event, relevant variables in PCA where q, Tair, VPD, NDVI, and precipitation. The results of this study suggest that CRNS is a suitable technique at field scale and that drydown curves are useful to quantify soil dryness and the influence of meteorological variables and crop development, thus providing an opportunity for water management in agriculture.

Stable isotope (δ18O, δ13C) analyses were performed on well preserved belemnites, oysters, and rhynchonellid brachiopods from the Middle to Upper Jurassic of the Morondava Basin in southern Madagascar. Both brachiopods and oysters indicate similar average temperatures of 18.7 to 19.3 °C in the Early Callovian, followed by a temperature decrease towards the Middle Oxfordian (13.9 °C) and a minimum in the Early Kimmeridgian (12.3 °C). In contrast, belemnites from the Oxfordian show lower average temperatures of 10.0 °C, which is likely caused by specific conditions for these organisms (e.g., different fractionation or life habits). Additionally, three oysters from the Upper Oxfordian and Lower Kimmeridgian were used for high-resolution stable isotope analyses. The data show seasonal fluctuations of >6 °C around averages between 14.4 and 14.7 °C. Latitudinal temperature gradients for the Callovian and Kimmeridgian are similar to today at the examined low latitudes of the southern hemisphere. The observed cooling of around 5 °C from the Callovian to the Oxfordian/Kimmeridgian can be attributed to a concurrent southward drift of Madagascar during the break-up of Gondwana. Thus, the study underlines the importance of considering palaeogeography in interpreting stable isotope data as well as the potential of detecting and timing palaeogeographic events by using stable isotope analyses.

The Aptian Crato Konservat-Lagerstätte is renowned for its exceptionally preserved fossils in lacustrine laminated limestones. Although previous works on this site include numerous taxonomic studies, its taphonomy remains a subject of debate. Herein, we present new data on the taphonomy of decapod crustaceans preserved in wrinkle laminites, highlighting the role of microbial mats in enhancing fossil preservation. Our results suggest that benthic microorganisms may have promoted protection and organic mineralization of some of the allochthonous to parautochthonous organic remains within the microbial laminites of the Crato lake. Overall, this work provides the first empirical evidence that the preservational pathways of the fossils in the Crato Konservat-Lagerstätte involved microbial mats.

Made available in DSpace on 2019-10-04T12:40:55Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-07-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Petrobras Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) The Aptian Romualdo Formation is a siliciclastic-dominated sedimentary unit recording the last marine ingression within the Cretaceous interior basins of northeastern Brazil. At the western margin of the Araripe Basin, rocks of the Romualdo Formation are mainly represented by carbonates resting abruptly over the Proterozoic crystalline basement. Detailed mapping and stratigraphic analysis revealed two stromatolite fields that were described and discussed for the first time. Several bioherms, biostromes and isolated stromatolites characterized by distinct microbialite morphologies associated with echinoid-rich strata have been identified, suggesting that hypersalinity, water depth and hydraulic conditions were the main factors controlling stromatolite morphogenesis. A cm-thick amalgamated bivalve rudstone, resting directly on the basement and representing a shell concentration formed above the fair-weather wave base was also recorded. Based on the regional distribution of the stromatolite types and associated sedimentary fades, we interpret the depositional environment as a local low gradient carbonate ramp deepening to the east. Our data robustly indicated that the western rocky shorelines of the Araripe Basin during the Aptian were populated by microbial mats and stromatolites in a condition analogous to the modern world-famous Hamelin Pool, Shark Bay, Western Australia. Finally, the development of stromatolites and echinoid-bearing microbialites at the western margin of the basin may be correlated with the formation of bakevelliid- and cassiopid-rich shell beds in the upper part of the Romualdo Formation at the eastern margin. (C) 2019 Elsevier B.V. All rights reserved. Univ Estadual Paulista, Inst Geociencias & Ciencias Exatas, Dept Geol Aplicada, Ave 24A,1515, BR-12506900 Rio Claro, Brazil Friedrich Alexander Univ Erlangen Nurnberg, FG Palaoumwelt, GeoZentrum Nordbayern, Loewenichstr 28, D-91054 Erlangen, Germany Univ Estadual Paulista, Inst Biociencias, Dept Zool, BR-18618000 Botucatu, SP, Brazil Univ Reg Cariri, Dept Ciencias Biol, Campus Pimenta 1161, BR-63100000 Crato, Brazil Univ Estadual Paulista, Inst Geociencias & Ciencias Exatas, Dept Geol Aplicada, Ave 24A,1515, BR-12506900 Rio Claro, Brazil Univ Estadual Paulista, Inst Biociencias, Dept Zool, BR-18618000 Botucatu, SP, Brazil FAPESP: 2016/13214-7 FAPESP: 2017/20803-1 FAPESP: 18/01750-7 Petrobras: 2014/00519-9 CNPq: 444070/2013-1 CNPq: 401039/2013-5 CNPq: 1082 30017/2015-3 CNPq: 152385/2016-9 CNPq: 301294/2018-6

The density of vertebrate fossils on bedding planes is generally very low in the Upper Jurassic plattenkalks forming the Solnhofen fossil Lagerstatte. There are, however, a few bedding planes where large concentrations of the small fis Leptolepides sprattiformis (BLAINVILLE, 1818) occur. The aim of this paper is to analyse and interpret these f sh concentrations from a taphonomic point of view. For this purpose, the taphonomic features of L. sprattiformis concentrations on three large slabs were semi-quantitatively analysed. The concentrations of individuals on bedding planes are explained as recording local mass mortality events caused by tropical storms that, for short intervals, disrupted the pycnocline which separated hypersaline, oxygen-poor to anoxic bottom waters from normal marine surface waters in the Plattenkalk basins. Mass mortality is supported by tetany features such as gaping jaws, hyperextended branchiostegal rays, and splayed f ns, which occur in the majority of the specimens. The generally excellent preservation of the f sh resulted from lack of postmortem f oatation, rapid burial and/or overgrowth by microbial f lms, and quick re-establishment of the pycnocline with inhospitable conditions on the basin floo. The post-mortem concave-arching of the backbones and various displacements of the vertebral column were most likely caused by varying decay resistance of soft tissues and the pressure of decay gases in the body cavities, respectively. The taphonomic analysis of f sh concentrations can provide very detailed palaeoenvironmental information and serves as an independent line of evidence for palaeoenvironmental reconstructions that complements geochemical and sedimentary data.

The palaeoecology of Spinicaudata, the dominant group of benthic invertebrates in many pre-Cenozoic freshwater environments, remains poorly understood. In analogy with extant taxa, it has been oversimplified and often reduced to shallow, temporary environments characterized by few trophic levels, implying ecological stasis from the Devonian to the Recent. We excavated 43 horizons of the Lower Cretaceous Yixian Formation (Anjiagou and Hengdaozi beds) to evaluate whether spinicaudatan ecology can be simplified to such an extent. Sedimentological evidence suggests general perennial conditions during the excavated lake interval. Based on 33226 specimen counts, we identified three arthropod-dominated macrobenthic associations and two assemblages. Response curves indicate that the spinicaudatan Eosestheria middendorfii was exceptionally tolerant to environmental gradients, followed, in decreasing order, by mayfly larvae, water boatmen and oligochaetes. Many spinicaudatan-yielding layers represent death after reproductive senescence rather than mass-mortality events. Spinicaudatan size varies significantly according to faunal association. A forward stepwise regression model suggests that growth responded to population density and diversity: lower densities and higher diversities triggered fast growth, and vice versa. The proposed strong density effect on carapace size has been corroborated by rearing experiments: as for E.middendorfii, natural log regression provided the best fit for the two extant species Eulimnadia texana and Eocyzicus argillaquus. Hence, E.middendorfii was a tolerant and morphologically variable species adapted to perennial waters and the frequent presence of higher trophic levels. Although there are rare records of extant taxa co-occurring with fish, the described Early Cretaceous environment is commonly not inhabited by extant Spinicaudata.

We study the out-of-equilibrium dynamics in the quantum Ising model with power-law interactions and positional disorder. For arbitrary dimension $d$ and interaction range $\alpha \geq d$ we analytically find a stretched exponential decay of the global magnetization and ensemble-averaged single-spin purity with a stretch-power $\beta = d/\alpha$ in the thermodynamic limit. Numerically, we confirm that glassy behavior persists for finite system sizes and sufficiently strong disorder. We identify dephasing between disordered coherent pairs as the main mechanism leading to a relaxation of global magnetization, whereas genuine many-body interactions lead to a loss of single-spin purity which signifies the build-up of entanglement. The emergence of glassy dynamics in the quantum Ising model extends prior findings in classical and open quantum systems, where the stretched exponential law is explained by a scale-invariant distribution of time scales, to both integrable and non-integrable quantum systems.