The origin and early evolution of planktic foraminifera

Abstrac

Trace Fossils in the Permian Rocks of English Riviera UNESCO Global Geopark

The Permian breccias, conglomerates and sandstones of the English Riviera UNESCO Global Geopark were deposited in quite harsh, desert environments just north of the Permian Equator. Body fossil evidence is completely lacking but rare trace fossils provide evidence of a land-based community. There is a variety of traces present, probably indicative of the presence of a range of unknown animals. Though these animals cannot be identified, their occurrence is important in the understanding of the biodiversity of these Permian environments

Priority Roadmap for Policy-Ready Contraceptive Research

Research can play a pivotal role in ensuring contraceptive access policy is evidence-informed, effective, and promotes universal, equitable access for all people. Yet, barriers— including differing priorities between researchers and policymakers and ineffective dissemination and translation of research findings—often impede the use of evidence in policymaking. Scientific evidence is one of several factors that shapes contraceptive access policy; however, the field lacks a shared understanding of the policy-relevant research needed to drive action toward equitable access.In response to this research-to-policy gap, the Coalition to Expand Contraceptive Access (CECA) led a collaborative, yearlong process to create a Priority Roadmap for Policy-Ready Contraceptive Research ("the Roadmap"). This process identified the research needed in the next decade to advance proactive domestic contraceptive access policy, consistent with a broader vision of Sexual and Reproductive Health Equity (SRHE) and wellbeing for all. By undertaking this effort, CECA aimed to:* Craft a long-term, national-level contraceptive access research and policy agenda informed by a broad group of stakeholders within the reproductive health field that meets the information needs of a range of policymakers and advocates.* Survey evidence needed to influence policy, leverage federal processes, and set the stage for statelevel implementation.* Position public and private funders to invest strategically in policy-ready research, researchers to carry out impactful research projects, and policymakers and advocates to use evidence effectively.The recommendations in this Roadmap have the potential to reshape the contraceptive access research and policy landscapes—by reconsidering the frameworks that guide us, the research questions we ask, and how we design, conduct, measure, interpret, and share research and related findings.

Gels under stress: the origins of delayed collapse

Attractive colloidal particles can form a disordered elastic solid or gel when quenched into a two-phase region, if the volume fraction is sufficiently large. When the interactions are comparable to thermal energies the stress-bearing network within the gel restructures over time as individual particle bonds break and reform. Typically, under gravity such weak gels show a prolonged period of either no or very slow settling, followed by a sudden and rapid collapse - a phenomenon known as delayed collapse. The link between local bond breaking events and the macroscopic process of delayed collapse is not well understood. Here we summarize the main features of delayed collapse and discuss the microscopic processes which cause it. We present a plausible model which connects the kinetics of bond breaking to gel collapse and test the model by exploring the effect of an applied external force on the stability of a gel.Comment: Accepted version: 10 pages, 7 figure

The wootton bassett mud spings (Wiltshire, U.K.): an unusual Largerstatten for jurassic foraminifera

Abstrac

FORAMINIFERAL CHARACTERISATION OF MID-UPPER JURASSIC SEQUENCES IN THE WESSEX BASIN (UNITED KINGDOM)

The use of foraminifera in the characterisation of sequences (systems tracts, maximum flooding surfaces, etc.) has developed over the last decade. Much of this work has been based in the Cenozoic successions of the Gulf of Mexico, although there is a growing application of such data in the Middle East and the North Sea Basin. The easiest surface to characterise has been the maximum flooding surface with its high diversity and high(er) abundance faunas; the characterisation of individual systems tracts has been less successful. Using the well-known mid-Upper Jurassic successions of the Dorset coastal sections, we have investigated a number of high resolution (para)sequences for their foraminiferal content. Using data of foraminiferal diversity and standing crops from a range of modern substrates we have investigated the potential faunas available after deposition, taphonomy, compaction, groundwater dissolution and modern weathering. By understanding the processes involved we have identified the key foraminiferal features of typical mid-Upper Jurassic sequences and indicated how this work may help in the correlation of successions in North Dorset and Normandy

An introduction to causes and consequences of Cretaceous sea-level changes (IGCP 609)

The International Geoscience Programme Project IGCP 609 addressed correlation, causes and consequences of short-term sea-level fluctuations during the Cretaceous. Processes causing several ka to several Ma (third- to fourth-order) sea-level oscillations during the Cretaceous are so far poorly understood. IGCP 609 proved the existence of sea-level cycles during potential ice sheet-free greenhouse to hothouse climate phases. These sea-level fluctuations were most probably controlled by aquifer-eustasy that is altering land-water storage owing to groundwater aquifer charge and discharge. The project investigated Cretaceous sea-level cycles in detail in order to differentiate and quantify both short- and long-term records based on orbital cyclicity. High-resolution sea-level records were correlated to the geological timescale resulting in a hierarchy of sea-level cycles in the longer Milankovitch band, especially in the 100 ka, 405 ka, 1.2 Ma and 2.4 Ma range. The relation of sea-level highs and lows to palaeoclimate events, palaeoenvironments and biota was also investigated using multiproxy studies. For a hothouse Earth such as the mid-Cretaceous, humid-arid climate cycles controlling groundwater-related sea-level change were evidenced by stable isotope data, correlation to continental lake-level records and humid-arid weathering cycles

Are there functional consequences of a reduction in selenium intake in UK subjects?

Dietary Se levels in the UK have fallen over the last 20 years and recent surveys indicate that average Se intakes are 30-40 microg/d, which is well below the current UK reference nutrient intake for adult men (75 microg/d) or women (60 microg/d). Functional consequences of this decline have not been recognised, although epidemiological data suggest it may contribute to increased risk of infections and incidence of some cancers. Previous data have indicated that biochemical changes in Se-dependent proteins occur in otherwise healthy UK subjects given small Se supplements. The current studies have focused on the effect of small Se supplements on the immune response since there is evidence of specific interactions between Se intake and viral replication, and since the potential anti-cancer effects of Se may be mediated by non-antioxidant effects of Se such as changes in immune function. Data indicate that subjects given small Se supplements (50 or 100 microg Se/d) have changes in the activity of Se-dependent enzymes and evidence of improved immune function and clearance of an administered live attenuated virus in the form of poliovirus vaccine. Responses of individual subjects to Se supplements are variable, and current work is evaluating potential explanations for this variability, including genetic variability and pre-existing Se status

A comparative study of fixed-bed and dispersed catalytic upgrading of heavy crude oil using-CAPRI

AbstractCAtalytic upgrading PRocess In-situ (CAPRI) incorporated with Toe-to-Heel Air Injection (THAI) for heavy oil and bitumen recovery and upgrading was studied for fixed-bed and dispersed catalysts. The extent of upgrading was evaluated in terms of API gravity, viscosity reduction, impurity removal, and true boiling point (TBP) distribution. The test was carried out using Co-Mo/Al2O3 at temperature of 425°C, pressure 20bar, and residence time of 10min. The dispersed catalyst was tested in a batch reactor. However, the residence time, catalyst-to-oil (CTO) ratios as well as the Reynolds numbers of both contacting patterns were kept the same to ensure dynamic similitude. It was found that the produced oil from dispersed ultrafine Co-Mo/Al2O3 catalyst (dp=2.6μm) exhibited superior light oil characteristics and quality than that produced with the fixed-bed of pelleted Co-Mo/Al2O3 (1.2mm diameter×2–5mm length). The API gravity of the feed oil was 13.8° and the produced oil showed an increase of 5.6° in the fixed bed and 8.7° with the dispersed catalyst. Unlike the fixed-bed of pelleted Co-Mo/Al2O3 which may suffer from diffusion limitations, rapid deactivation, and channelling effect, the ultrafine particles presented high surface area to volume ratio, reducing the chances of pore plugging, have more accessible reaction sites per unit mass, and lead to enhanced cracking of macromolecules. Moreover, the reduction of sulphur of 38.6% and (Ni+V) content of 85.2% in the produced oil show greater heteroatom removal compared to 29% (sulphur) and 45.6% (Ni+V) observed in the product from the fixed-bed

Ichthyolith evidence for the age of reflector A u, Deep sea drilling project site 603

Reflector A u is extensively developed along the western margin of the North Atlantic Ocean. Evidence from ichthyoliths (fish skeletal debris) would suggest that the sediments immediately overlying the prominent hiatus are of early Miocene age