Effect of diagenesis on compaction of reservoir rocks

Predicting sediment porosity-depth trends and ultimately the quality of reservoir rocks requires an understanding of mechanical and chemical compaction mechanisms during diagenesis. In many siliciclastic sediments porosity versus depth profiles can be predicted from the sediment’s stress history. In carbonates such predictions are more difficult because chemical diagenesis is prevalent even within a few meters of the seafloor. We used a systematic laboratory approach to investigate the influence of early diagenesis in a meteoric environment on compaction of oolitic carbonates. Aggregates were synthesized in an autoclave from loosely packed natural aragonite ooids and fresh water, to mimic phreatic conditions. Time and temperature were used to control the degree of chemical diagenesis. Constant stress-rate, uniaxial strain compaction tests were performed on the aggregates to track mechanical properties as a function of chemical alteration. Samples were characterized before and after compaction with electron and optical microscopy, X-ray tomography, and X-ray diffraction. The aragonite ooids dissolved preferentially inwards from their rims, and blocky calcite precipitated in the original inter-ooid pore space with little change in porosity. This progression results in an inverted structure with moldic pores inside a foam-like structure of calcite. With deformation, all samples exhibited elastic to plastic compaction typical of granular aggregates. With increasing alteration, the elastic moduli appear to increase, the transition to plastic behavior occurs at progressively higher stresses, and the elastic-plastic transition becomes more abrupt. At high stresses the plastic behavior was similar for all samples. X-ray tomography with micron-scale resolution tracks grain displacement and void and cement compaction. These experiments and results help us understand the complexities of chemical-mechanical interactions during diagenesis and improve our ability to predict porosity changes with depth for basin modeling, reservoir quality prediction and reservoir management

Nucleotide sequence and chromosomal location of Cab -7, the tomato gene encoding the type II chlorophyll a/b-binding polypeptide of photosystem I

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43420/1/11103_2004_Article_BF00016015.pd

Syndromic Surveillance for Influenzalike Illness in Ambulatory Care Setting

Detection algorithm using proxy data for a bioterrorism agent release and historical data for influenza was effective

Evidence that tissue resident human enthesis γδ T-cells can produce IL-17A independently of IL-23R transcript expression

Objectives: Murine models of interleukin (IL)-23-driven spondyloarthritis (SpA) have demonstrated entheseal accumulation of Î 3Î T-cells which were responsible for the majority of local IL-17A production. However, IL-23 blockers are ineffective in axial inflammation in man. This study investigated Î 3Î T-cell subsets in the normal human enthesis to explore the biology of the IL-23/17 axis. Methods: Human spinous processes entheseal soft tissue (EST) and peri-entheseal bone (PEB) were harvested during elective orthopaedic procedures. Entheseal Î 3Î T-cells were evaluated using immunohistochemistry and isolated and characterised using flow cytometry. RNA was isolated from Î 3Î T-cell subsets and analysed by qPCR. Entheseal Î 3Î T-cells were stimulated with phorbol 12-myristate 13-acetate (PMA) and ionomycin, anti-CD3/28 or IL-23 and IL-17A production was measured by high-sensitivity ELISA and qPCR. Results: Entheseal Î 3Î T-cells were confirmed immunohistochemically with VÎ 1 and VÎ 2 subsets that are cytometrically defined. Transcript profiles of both cell populations suggested tissue residency and immunomodulatory status. Entheseal VÎ 2 cells expressed high relative abundance of IL-23/17-associated transcripts including IL-23R, RORC and CCR6, whereas the VÎ 1 subset almost completely lacked detectable IL-23R transcript. Following PMA stimulation IL-17A was detectable in both VÎ 1 and VÎ 2 subsets, and following CD3/CD28 stimulation both subsets showed IL-17A and IL-17F transcripts with neither transcript being detectable in the VÎ 1 subset following IL-23 stimulation. Conclusion: Spinal entheseal VÎ 1 and VÎ 2 subsets are tissue resident cells with inducible IL-17A production with evidence that the VÎ 1 subset does so independently of IL-23R expression

Research priorities for the COVID-19 pandemic and beyond: A call to action for psychological science

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) that has caused the coronavirus disease 2019 (COVID-19) pandemic represents the greatest international biopsychosocial emergency the world has faced for a century, and psychological science has an integral role to offer in helping societies recover. The aim of this paper is to set out the shorter- and longer-term priorities for research in psychological science that will (a) frame the breadth and scope of potential contributions from across the discipline; (b) enable researchers to focus their resources on gaps in knowledge; and (c) help funders and policymakers make informed decisions about future research priorities in order to best meet the needs of societies as they emerge from the acute phase of the pandemic. The research priorities were informed by an expert panel convened by the British Psychological Society that reflects the breadth of the discipline; a wider advisory panel with international input; and a survey of 539 psychological scientists conducted early in May 2020. The most pressing need is to research the negative biopsychosocial impacts of the COVID-19 pandemic to facilitate immediate and longer-term recovery, not only in relation to mental health, but also in relation to behaviour change and adherence, work, education, children and families, physical health and the brain, and social cohesion and connectedness. We call on psychological scientists to work collaboratively with other scientists and stakeholders, establish consortia, and develop innovative research methods while maintaining high-quality, open, and rigorous research standards

Research priorities for the COVID-19 pandemic and beyond: A call to action for psychological science

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) that has caused the coronavirus disease 2019 (COVID-19) pandemic represents the greatest international biopsychosocial emergency the world has faced for a century, and psychological science has an integral role to offer in helping societies recover. The aim of this paper is to set out the shorter- and longer-term priorities for research in psychological science that will (a) frame the breadth and scope of potential contributions from across the discipline; (b) enable researchers to focus their resources on gaps in knowledge; and (c) help funders and policymakers make informed decisions about future research priorities in order to best meet the needs of societies as they emerge from the acute phase of the pandemic. The research priorities were informed by an expert panel convened by the British Psychological Society that reflects the breadth of the discipline; a wider advisory panel with international input; and a survey of 539 psychological scientists conducted early in May 2020. The most pressing need is to research the negative biopsychosocial impacts of the COVID-19 pandemic to facilitate immediate and longer-term recovery, not only in relation to mental health, but also in relation to behaviour change and adherence, work, education, children and families, physical health and the brain, and social cohesion and connectedness. We call on psychological scientists to work collaboratively with other scientists and stakeholders, establish consortia, and develop innovative research methods while maintaining high-quality, open, and rigorous research standards