Capillary disconnect during drying in model porous media at different wettability

[EN] We carried out drying studies on a 2.5D micromodel based on a thin section of a carbonate rock to investigate the impact of wettability on the capillary disconnect, the moment when liquid films de-pin from the external evaporating surface. While this is coincident with the transition to low evaporation rate (diffusion limited) for deionized-water, our experiments show, the corner wetting films persisted after the transition to low evaporation rate for both water-wet and mixed-wet micromodels for brine, as solid salt continued to build up at the external evaporating surface. Fully oil wet micromodels showed a drying rate transition coincident with de-pinning.We gratefully acknowledge funding for this PhD research from the Petroleum Technology Development Fund, provided by the Nigerian Government. This work was done using equipment provided by the Qatar Carbonates and Carbon Storage Research Centre (QCCSRC). We gratefully acknowledge the funding of QCCSRC provided jointly by Qatar Petroleum, Shell, and the Qatar Science & Technology Park.Rufai, A.; Crawshaw, J. (2018). Capillary disconnect during drying in model porous media at different wettability. En IDS 2018. 21st International Drying Symposium Proceedings. Editorial Universitat Politècnica de València. 1237-1244. https://doi.org/10.4995/IDS2018.2018.7313OCS1237124

Chemical resolution in T 2 - T 1 correlations

Oil and water fractions have been identified in fluid saturated carbonate rock cores using a novel T2-T1-d pulse sequence. The inclusion of the chemical shift dimension d allows T2-T1 plots to be generated independently for the oil and water. The T2-T1-d pulse sequence utilises a “double-shot” T1 measurement that provides free induction decays (FIDs) as a function of both relaxation times for suitably broad line samples. The T2-T1-d data set is acquired in the same experimental time as a conventional T1-T2 measurement (without chemical resolution) of equivalent data density. Here we demonstrate that different behaviour can be observed between the oil and water fractions in water wet and preferentially oil wet cores, and that saturation states can be determined. This technique could provide a quantitative NMR measure of wettability

The cucumber mosaic virus 1a protein regulates interactions between the 2b protein and ARGONAUTE 1 while maintaining the silencing suppressor activity of the 2b protein

The cucumber mosaic virus (CMV) 2b viral suppressor of RNA silencing (VSR) is a potent counter-defense and pathogenicity factor that inhibits antiviral silencing by titration of short double-stranded RNAs. It also disrupts microRNA-mediated regulation of host gene expression by binding ARGONAUTE 1 (AGO1). But in Arabidopsis thaliana complete inhibition of AGO1 is counterproductive to CMV since this triggers another layer of antiviral silencing mediated by AGO2, de-represses strong resistance against aphids (the insect vectors of CMV), and exacerbates symptoms. Using confocal laser scanning microscopy, bimolecular fluorescence complementation, and co-immunoprecipitation assays we found that the CMV 1a protein, a component of the viral replicase complex, regulates the 2b-AGO1 interaction. By binding 2b protein molecules and sequestering them in P-bodies, the 1a protein limits the proportion of 2b protein molecules available to bind AGO1, which ameliorates 2b-induced disease symptoms, and moderates induction of resistance to CMV and to its aphid vector. However, the 1a protein-2b protein interaction does not inhibit the ability of the 2b protein to inhibit silencing of reporter gene expression in agroinfiltration assays. The interaction between the CMV 1a and 2b proteins represents a novel regulatory system in which specific functions of a VSR are selectively modulated by another viral protein. The finding also provides a mechanism that explains how CMV, and possibly other viruses, modulates symptom induction and manipulates host-vector interactions

The cucumber mosaic virus 1a protein regulates interactions between the 2b protein and ARGONAUTE 1 while maintaining the silencing suppressor activity of the 2b protein

The cucumber mosaic virus (CMV) 2b viral suppressor of RNA silencing (VSR) is a potent counter-defense and pathogenicity factor that inhibits antiviral silencing by titration of short double-stranded RNAs. It also disrupts microRNA-mediated regulation of host gene expression by binding ARGONAUTE 1 (AGO1). But in Arabidopsis thaliana complete inhibition of AGO1 is counterproductive to CMV since this triggers another layer of antiviral silencing mediated by AGO2, de-represses strong resistance against aphids (the insect vectors of CMV), and exacerbates symptoms. Using confocal laser scanning microscopy, bimolecular fluorescence complementation, and co-immunoprecipitation assays we found that the CMV 1a protein, a component of the viral replicase complex, regulates the 2b-AGO1 interaction. By binding 2b protein molecules and sequestering them in P-bodies, the 1a protein limits the proportion of 2b protein molecules available to bind AGO1, which ameliorates 2b-induced disease symptoms, and moderates induction of resistance to CMV and to its aphid vector. However, the 1a protein-2b protein interaction does not inhibit the ability of the 2b protein to inhibit silencing of reporter gene expression in agroinfiltration assays. The interaction between the CMV 1a and 2b proteins represents a novel regulatory system in which specific functions of a VSR are selectively modulated by another viral protein. The finding also provides a mechanism that explains how CMV, and possibly other viruses, modulates symptom induction and manipulates host-vector interactions

Responsive Operations for Key Services (ROKS): A Modular, Low SWaP Quantum Communications Payload

Quantum key distribution (QKD) is a theoretically proven future-proof secure encryption method that inherits its security from fundamental physical principles. With a proof-of-concept QKD payload having flown on the Micius satellite since 2016, efforts have intensified globally. Craft Prospect, working with a number of UK organisations, has been focused on miniaturising the technologies that enable QKD so that they may be used in smaller platforms including nanosatellites. The significant reduction of size, and therefore the cost of launching quantum communication technologies either on a dedicated platform or hosted as part of a larger optical communications will improve potential access to quantum encryption on a relatively quick timescale. The Responsive Operations for Key Services (ROKS) mission seeks to be among the first to send a QKD payload on a CubeSat into low Earth orbit, demonstrating the capabilities of newly developed modular quantum technologies. The ROKS payload comprises a quantum source module that supplies photons randomly in any of four linear polarisation states fed from a quantum random number generator; an acquisition, pointing, and tracking system to fine-tune alignment of the quantum source beam with an optical ground station; an imager that will detect cloud cover autonomously; and an onboard computer that controls and monitors the other modules, which manages the payload and assures the overall performance and security of the system. Each of these modules have been developed with low Size, Weight and Power (SWaP) for CubeSats, but with interoperability in mind for other satellite form factors. We present each of the listed components, together with the initial test results from our test bench and the performance of our protoflight models prior to initial integration with the 6U CubeSat platform systems. The completed ROKS payload will be ready for flight at the end of 2022, with various modular components already being baselined for flight and integrated into third party communication missions