Experimental assessment of pore fluid distribution and geomechanical changes in saline sandstone reservoirs during and after CO2 injection

Responsible CO2 geosequestration requires a comprehensive assessment of the geomechanical integrity of saline reservoir formations during and after CO2 injection. We assessed the geomechanical effects of CO2 injection and post-injection aquifer recharge on weakly cemented, synthetic-sandstone (38% porosity) sample in the laboratory under dry and brine-saturated conditions, before and after subjecting the sample to variable pore pressure brine-CO2 flow-through tests (∼170 h). We measured ultrasonic P- and S-wave velocities (Vp, Vs) and attenuations, electrical resistivity and volumetric strain (εv). Vs was found to be an excellent indicator of mechanical deformation during CO2 injection; Vp gives mechanical and pore fluid distribution information, allowing quantification of the individual contribution of both phenomena when combined with resistivity. Abrupt strain recovery during imbibition suggests that aquifer recharge after ceasing CO2 injection might affect the geomechanical stability of the reservoir. Static and dynamic parameters indicate the sample experienced minor geomechanical changes during CO2 exposure, with an increase of Δεv <3% and a drop in ΔVs ∼1%. In contrast, due to brine-induced hydro-mechanical alteration, Δεv increased by ∼10% and ΔVs by ∼6%. This study provides a multiparameter, thermo-hydro-mechanical-chemical database needed to validate monitoring tools and simulators, for prediction of the geomechanical behaviour of CO2 storage reservoirs

Length of carotid stenosis predicts peri-procedural stroke or death and restenosis in patients randomized to endovascular treatment or endarterectomy.

BACKGROUND: The anatomy of carotid stenosis may influence the outcome of endovascular treatment or carotid endarterectomy. Whether anatomy favors one treatment over the other in terms of safety or efficacy has not been investigated in randomized trials. METHODS: In 414 patients with mostly symptomatic carotid stenosis randomized to endovascular treatment (angioplasty or stenting; n = 213) or carotid endarterectomy (n = 211) in the Carotid and Vertebral Artery Transluminal Angioplasty Study (CAVATAS), the degree and length of stenosis and plaque surface irregularity were assessed on baseline intraarterial angiography. Outcome measures were stroke or death occurring between randomization and 30 days after treatment, and ipsilateral stroke and restenosis ≥50% during follow-up. RESULTS: Carotid stenosis longer than 0.65 times the common carotid artery diameter was associated with increased risk of peri-procedural stroke or death after both endovascular treatment [odds ratio 2.79 (1.17-6.65), P = 0.02] and carotid endarterectomy [2.43 (1.03-5.73), P = 0.04], and with increased long-term risk of restenosis in endovascular treatment [hazard ratio 1.68 (1.12-2.53), P = 0.01]. The excess in restenosis after endovascular treatment compared with carotid endarterectomy was significantly greater in patients with long stenosis than with short stenosis at baseline (interaction P = 0.003). Results remained significant after multivariate adjustment. No associations were found for degree of stenosis and plaque surface. CONCLUSIONS: Increasing stenosis length is an independent risk factor for peri-procedural stroke or death in endovascular treatment and carotid endarterectomy, without favoring one treatment over the other. However, the excess restenosis rate after endovascular treatment compared with carotid endarterectomy increases with longer stenosis at baseline. Stenosis length merits further investigation in carotid revascularisation trials

Overcoming the mobility penalty introduced by dipole disorder in small-molecule HTM films

The importance of the hole-transport material (HTM) in perovskite solar cells (PSCs) is now very well-established, with state-of-the-art materials such as Spiro-OMeTAD attracting significant attention in the last decade. The high cost of such materials still limits the commercialisation of these HTMs. To tackle this, the amide linker has recently been introduced into HTM systems via EDOT-Amide-TPA, utilising condensation chemistry as a cheap and effective route to HTMs. EDOT-Amide-TPA is capable of a variety of intermolecular interactions such as dipole-dipole interactions and hydrogen bonding, both of which are beneficial for enhancing the film morphology and improving charge transport. However, the interplay between these different interactions is not trivial, and understanding how they affect each other is paramount to inform new HTM designs whilst minimising material waste. To date, studies investigating the combined effects of different intermolecular interactions within the HTL on the charge transport properties of these materials are lacking. Furthermore, dipole disorder within the film introduces a mobility ‘penalty’: mobility decreases with stronger overall dipole due to energetic disorder within the film, which hinders charge hopping. In this work, we investigate three amide-based HTM analogs with differing intermolecular interaction capabilities, and show that this penalty can be compensated by a preferentially increased dipole ordering, likely achieved through intermolecular hydrogen bonding. This effectively cancels out the dipole disorder while retaining the beneficial effects on the molecular packing. Our aim is that this work provides a good foundation for navigating the complex interplay between hydrogen bonding, dipole moments, conductivity, and film formation in small-molecule HTMs

Effective implementation of research into practice: an overview of systematic reviews of the health literature

<p>Abstract</p> <p>Background</p> <p>The gap between research findings and clinical practice is well documented and a range of interventions has been developed to increase the implementation of research into clinical practice.</p> <p>Findings</p> <p>A review of systematic reviews of the effectiveness of interventions designed to increase the use of research in clinical practice. A search for relevant systematic reviews was conducted of Medline and the Cochrane Database of Reviews 1998-2009. 13 systematic reviews containing 313 primary studies were included. Four strategy types are identified: audit and feedback; computerised decision support; opinion leaders; and multifaceted interventions. Nine of the reviews reported on multifaceted interventions. This review highlights the small effects of single interventions such as audit and feedback, computerised decision support and opinion leaders. Systematic reviews of multifaceted interventions claim an improvement in effectiveness over single interventions, with effect sizes ranging from small to moderate. This review found that a number of published systematic reviews fail to state whether the recommended practice change is based on the best available research evidence.</p> <p>Conclusions</p> <p>This overview of systematic reviews updates the body of knowledge relating to the effectiveness of key mechanisms for improving clinical practice and service development. Multifaceted interventions are more likely to improve practice than single interventions such as audit and feedback. This review identified a small literature focusing explicitly on getting research evidence into clinical practice. It emphasizes the importance of ensuring that primary studies and systematic reviews are precise about the extent to which the reported interventions focus on changing practice based on research evidence (as opposed to other information codified in guidelines and education materials).</p

School closures during the 2009 influenza pandemic: national and local experiences

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Long-range DNA looping and gene expression analyses identify DEXI as an autoimmune disease candidate gene

The chromosome 16p13 region has been associated with several autoimmune diseases, including type 1 diabetes (T1D) and multiple sclerosis (MS). CLEC16A has been reported as the most likely candidate gene in the region, since it contains the most disease-associated single-nucleotide polymorphisms (SNPs), as well as an imunoreceptor tyrosine-based activation motif. However, here we report that intron 19 of CLEC16A, containing the most autoimmune disease-associated SNPs, appears to behave as a regulatory sequence, affecting the expression of a neighbouring gene, DEXI. The CLEC16A alleles that are protective from T1D and MS are associated with increased expression of DEXI, and no other genes in the region, in two independent monocyte gene expression data sets. Critically, using chromosome conformation capture (3C), we identified physical proximity between the DEXI promoter region and intron 19 of CLEC16A, separated by a loop of >150 kb. In reciprocal experiments, a 20 kb fragment of intron 19 of CLEC16A, containing SNPs associated with T1D and MS, as well as with DEXI expression, interacted with the promotor region of DEXI but not with candidate DNA fragments containing other potential causal genes in the region, including CLEC16A. Intron 19 of CLEC16A is highly enriched for transcription-factor-binding events and markers associated with enhancer activity. Taken together, these data indicate that although the causal variants in the 16p13 region lie within CLEC16A, DEXI is an unappreciated autoimmune disease candidate gene, and illustrate the power of the 3C approach in progressing from genome-wide association studies results to candidate causal genes

Error sources and data limitations for the prediction ofsurface gravity: a case study using benchmarks

Gravity-based heights require gravity values at levelled benchmarks (BMs), whichsometimes have to be predicted from surrounding observations. We use EGM2008 andthe Australian National Gravity Database (ANGD) as examples of model and terrestrialobserved data respectively to predict gravity at Australian national levelling network(ANLN) BMs. The aim is to quantify errors that may propagate into the predicted BMgravity values and then into gravimetric height corrections (HCs). Our results indicatethat an approximate ±1 arc-minute horizontal position error of the BMs causesmaximum errors in EGM2008 BM gravity of ~ 22 mGal (~55 mm in the HC at ~2200 melevation) and ~18 mGal for ANGD BM gravity because the values are not computed atthe true location of the BM. We use RTM (residual terrain modelling) techniques toshow that ~50% of EGM2008 BM gravity error in a moderately mountainous regioncan be accounted for by signal omission. Non-representative sampling of ANGDgravity in this region may cause errors of up to 50 mGals (~120 mm for the Helmertorthometric correction at ~2200 m elevation). For modelled gravity at BMs to beviable, levelling networks need horizontal BM positions accurate to a few metres, whileRTM techniques can be used to reduce signal omission error. Unrepresentative gravitysampling in mountains can be remedied by denser and more representative re-surveys,and/or gravity can be forward modelled into regions of sparser gravity

Caenorhabditis elegans is a useful model for anthelmintic discovery

Parasitic nematodes infect one quarter of the world's population and impact all humans through widespread infection of crops and livestock. Resistance to current anthelmintics has prompted the search for new drugs. Traditional screens that rely on parasitic worms are costly and labour intensive and target-based approaches have failed to yield novel anthelmintics. Here, we present our screen of 67,012 compounds to identify those that kill the non-parasitic nematode Caenorhabditis elegans. We then rescreen our hits in two parasitic nematode species and two vertebrate models (HEK293 cells and zebrafish), and identify 30 structurally distinct anthelmintic lead molecules. Genetic screens of 19 million C. elegans mutants reveal those nematicides for which the generation of resistance is and is not likely. We identify the target of one lead with nematode specificity and nanomolar potency as complex II of the electron transport chain. This work establishes C. elegans as an effective and cost-efficient model system for anthelmintic discovery

Role of Sphingomyelin Synthase in Controlling the Antimicrobial Activity of Neutrophils against Cryptococcus neoformans

The key host cellular pathway(s) necessary to control the infection caused by inhalation of the environmental fungal pathogen Cryptococcus neoformans are still largely unknown. Here we have identified that the sphingolipid pathway in neutrophils is required for them to exert their killing activity on the fungus. In particular, using both pharmacological and genetic approaches, we show that inhibition of sphingomyelin synthase (SMS) activity profoundly impairs the killing ability of neutrophils by preventing the extracellular release of an antifungal factor(s). We next found that inhibition of protein kinase D (PKD), which controls vesicular sorting and secretion and is regulated by diacylglycerol (DAG) produced by SMS, totally blocks the extracellular killing activity of neutrophils against C. neoformans. The expression of SMS genes, SMS activity and the levels of the lipids regulated by SMS (namely sphingomyelin (SM) and DAG) are up-regulated during neutrophil differentiation. Finally, tissue imaging of lungs infected with C. neoformans using matrix-assisted laser desorption-ionization mass spectrometry (MALDI-MS), revealed that specific SM species are associated with neutrophil infiltration at the site of the infection. This study establishes a key role for SMS in the regulation of the killing activity of neutrophils against C. neoformans through a DAG-PKD dependent mechanism, and provides, for the first time, new insights into the protective role of host sphingolipids against a fungal infection

The broad-lined Type-Ic supernova SN 2022xxf with extraordinary two-humped light curves

We report on our study of supernova (SN) 2022xxf based on observations obtained during the first four months of its evolution. The light curves (LCs) display two humps of similar maximum brightness separated by 75 days, unprecedented for a broad-lined (BL) Type Ic supernova (SN IcBL). SN 2022xxf is the most nearby SN IcBL to date (in NGC 3705, $z = 0.0037$, at a distance of about 20 Mpc). Optical and near-infrared photometry and spectroscopy are used to identify the energy source powering the LC. Nearly 50 epochs of high signal-to-noise-ratio spectroscopy were obtained within 130 days, comprising an unparalleled dataset for a SN IcBL, and one of the best-sampled SN datasets to date. The global spectral appearance and evolution of SN 2022xxf points to typical SN Ic/IcBL, with broad features (up to $\sim14000$ km s$^{-1}$) and a gradual transition from the photospheric to the nebular phase. However, narrow emission lines (corresponding to $\sim1000-2500$ km s$^{-1}$) are present in the spectra from the time of the second rise, suggesting slower-moving circumstellar material (CSM). These lines are subtle, in comparison to the typical strong narrow lines of CSM-interacting SNe, for example, Type IIn, Ibn, and Icn, but some are readily noticeable at late times such as in Mg I $\lambda$5170 and [O I] $\lambda$5577. Unusually, the near-infrared spectra show narrow line peaks in a number of features formed by ions of O and Mg. We infer the presence of CSM that is free of H and He. We propose that the radiative energy from the ejecta-CSM interaction is a plausible explanation for the second LC hump. This interaction scenario is supported by the color evolution, which progresses to the blue as the light curve evolves along the second hump, and the slow second rise and subsequent rapid LC drop. (Abstract abridged)Comment: Accepted versio