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An integrated approach to seismic stimulation of oil reservoirs: laboratory, field and theoretical results from DOE/industry collaborations.
It has been observed repeatedly that low-frequency (10-500 Hz) seismic stress waves can enhance oil production from depleted reservoirs . Until recently, the majority of these observations have been anecdotal or at the proof-of-concept level. The physics coupling stress waves to multiphase fluid flow behavior in porous media is still poorly understood, even though numerous underlying physical mechanisms have been proposed to explain the observations . Basic research on the phenomenon is being conducted through a U .S. Department of Energy funded collaboration between Lawrence Berkeley National Laboratory, the University of California at Berkeley, Los Alamos National Laboratory and the U .S . oil and gas industry . The project has focused on three main areas of research: (1) laboratory core flow experiments, (2) field seismic monitoring of downhole stimulation tests, and (3) theoretical modeling of the coupled stress/flow phenomenon . The major goal is to obtain a comprehensive scientific understanding of the seismic stimulation phenomenon so that field application technologies can be improved. Initial developments and experimental results in all three research focus areas confirm historic observations that the stimulated flow phenomenon is real and that a fundamental scientific understanding can be obtained through continued research . Examples of project results and developments are presented here
Correction to: RIC in COVID-19âa Clinical Trial to Investigate Whether Remote Ischemic Conditioning (RIC) Can Prevent Deterioration to Critical Care in Patients with COVID-19
Purpose:
Coronavirus disease 19 (COVID-19) has, to date, been diagnosed in over 130 million persons worldwide and is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Several variants of concern have emerged including those in the United Kingdom, South Africa, and Brazil. SARS-CoV-2 can cause a dysregulated inflammatory response known as a cytokine storm, which can progress rapidly to acute respiratory distress syndrome (ARDS), multi-organ failure, and death. Suppressing these cytokine elevations may be key to improving outcomes. Remote ischemic conditioning (RIC) is a simple, non-invasive procedure whereby a blood pressure cuff is inflated and deflated on the upper arm for several cycles. âRIC in COVID-19â is a pilot, multi-center, randomized clinical trial, designed to ascertain whether RIC suppresses inflammatory cytokine production.
Methods:
A minimum of 55 adult patients with diagnosed COVID-19, but not of critical status, will be enrolled from centers in the United Kingdom, Brazil, and South Africa. RIC will be administered daily for up to 15 days. The primary outcome is the level of inflammatory cytokines that are involved in the cytokine storm that can occur following SARS-CoV-2 infection. The secondary endpoint is the time between admission and until intensive care admission or death. The in vitro cytotoxicity of patient blood will also be assessed using primary human cardiac endothelial cells.
Conclusions:
The results of this pilot study will provide initial evidence on the ability of RIC to suppress the production of inflammatory cytokines in the setting of COVID-19.
Trial Registration:
NCT04699227, registered January 7th, 2021
Effect of Remote Ischaemic Conditioning on the Inflammatory Cytokine Cascade of COVID-19 (RIC in COVID-19): a Randomized Controlled Trial
Purpose: Patients hospitalized with COVID-19 may develop a hyperinflammatory, dysregulated cytokine âstormâ that rapidly progresses to acute respiratory distress syndrome, multiple organ dysfunction, and even death. Remote ischaemic conditioning (RIC) has elicited anti-inflammatory and cytoprotective benefits by reducing cytokines following sepsis in animal studies. Therefore, we investigated whether RIC would mitigate the inflammatory cytokine cascade induced by COVID-19. Methods: We conducted a prospective, multicentre, randomized, sham-controlled, single-blind trial in Brazil and South Africa. Non-critically ill adult patients with COVID-19 pneumonia were randomly allocated (1:1) to receive either RIC (intermittent ischaemia/reperfusion applied through four 5-min cycles of inflation (20Â mmHg above systolic blood pressure) and deflation of an automated blood-pressure cuff) or sham for approximately 15Â days. Serum was collected following RIC/sham administration and analyzed for inflammatory cytokines using flow cytometry. The endpoint was the change in serum cytokine concentrations. Participants were followed for 30Â days. Results: Eighty randomized participants (40 RIC and 40 sham) completed the trial. Baseline characteristics according to trial intervention were overall balanced. Despite downward trajectories of all cytokines across hospitalization, we observed no substantial changes in cytokine concentrations after successive days of RIC. Time to clinical improvement was similar in both groups (HR 1.66; 95% CI, 0.938â2.948, p 0.08). Overall RIC did not demonstrate a significant impact on the composite outcome of all-cause death or clinical deterioration (HR 1.19; 95% CI, 0.616â2.295, p = 0.61). Conclusion: RIC did not reduce the hypercytokinaemia induced by COVID-19 or prevent clinical deterioration to critical care. Trial Registration: ClinicalTrials.gov Identifier: NCT04699227
Aberrant chromatin landscape following loss of the H3.3 chaperone Daxx in haematopoietic precursors leads to Pu.1-mediated neutrophilia and inflammation
Defective silencing of retrotransposable elements has been linked to inflammageing, cancer and autoimmune diseases. However, the underlying mechanisms are only partially understood. Here we implicate the histone H3.3 chaperone Daxx, a retrotransposable element repressor inactivated in myeloid leukaemia and other neoplasms, in protection from inflammatory disease. Loss of Daxx alters the chromatin landscape, H3.3 distribution and histone marks of haematopoietic progenitors, leading to engagement of a Pu.1-dependent transcriptional programme for myelopoiesis at the expense of B-cell differentiation. This causes neutrophilia and inflammation, predisposing mice to develop an autoinflammatory skin disease. While these molecular and phenotypic perturbations are in part reverted in animals lacking both Pu.1 and Daxx, haematopoietic progenitors in these mice show unique chromatin and transcriptome alterations, suggesting an interaction between these two pathways. Overall, our findings implicate retrotransposable element silencing in haematopoiesis and suggest a cross-talk between the H3.3 loading machinery and the pioneer transcription factor Pu.1
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