Naresuan University Journal
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Development, Property and International Investment:The Double-edged Sword of Human Rights
No full textBiostimulation by Glycerol Phosphate to Precipitate Recalcitrant Uranium(IV) Phosphate
No full textStimulating the microbial reduction of aqueous uranium(VI) to insoluble U(IV) via electron donor addition has been proposed as a strategy to remediate uranium-contaminated groundwater in situ. However, concerns have been raised regarding the longevity of microbially-precipitated U(IV) in the subsurface, particularly as it may become remobilised if the conditions change to become oxidising. An alternative mechanism is to stimulate the precipitation of poorly soluble uranium phosphates via the addition of an organophosphate and promote the development of reducing conditions. Here we selected a sediment sample from a UK nuclear site and stimulated the microbial community with glycerol phosphate under anaerobic conditions to assess whether uranium phosphate precipitation was a viable bioremediation strategy. Results showed that U(VI) was rapidly removed from solution and precipitated as a reduced crystalline U(IV)-phosphate mineral similar to ningyoite. This mineral was considerably more recalcitrant to oxidative remobilisation than the products of microbial U(VI) reduction. Bacteria closely related to Pelosinus species may have played a key role in uranium removal in these experiments. This work has implications for the stewardship of uranium-contaminated groundwater, with the formation of U(IV)-phosphates potentially offering a more effective strategy for maintaining low concentrations of uranium in groundwater over long time periods
Directed Lithiation of Pentadienylsilanes
No full textDeprotonation of dimethyl(pyrrolidylmethyl)silylpentadiene (5) and bis(2-rnethoxyethyl)aminomethyl(dimethyl)silylpentadiene (7) with (BuLi)-Bu-n/tmeda and (BuLi)-Bu-n, respectively, results in their corresponding lithium complexes, 6 and 8. The lithium cation in 6 is coordinated by an eta(1)-pentadienyl ligand via the alpha-carbon and by the pendant pyrrolidyl group. The lithium cation in 8 is eta(2) coordinated by the pentadienyl alpha- and beta-carbons and by the bis(methoxyethyl)amino group. The structure of 6 is retained in benzene solution, but in thf the tmeda coligand is displaced by the solvent. A 3.5:1 mixture of the W- and S-conformations of the pentadienyl carbons was observed for 8 in benzene. DFT calculations of NBO charges for the pentadienyl carbons in 6 and 8 show that lithium polarizes the electron density toward the alpha-carbon, although a series of electrophile quenching reactions with 6 show that regioselectivity does not depend on the electronic structure of the pentadienyl carbanion
Search for production of vector-like quark pairs and of four top quarks in the lepton-plus-jets final state in collisions at TeV with the ATLAS detector
No full textSearch for invisible decays of the Higgs boson produced in association with a hadronically decaying vector boson in collisions at = 8 TeV with the ATLAS detector
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Experimental and numerical investigations of fire resistance of continuous high strength steel reinforced concrete T-beams
No full textThis paper presents experimental and numerical results of performance and fire endurance of high strength steel reinforced concrete (RC) continuous T-beams under the standard ISO 834 condition. The fire tests included six specimens using steel reinforcement of 500MPa yield strength with different load levels and reinforcement ratios. In all cases, the failure mode was flexural failure due to the formation of a plastic hinge mechanism. However the sequence of plastic hinge appearance was different from that at ambient temperature due to the increased support bending moments in fire as a result of restrained thermal bowing. Formation of a plastic hinge mechanism indicates sufficient reinforcement ductility to enable complete redistribution of bending moments and absence of any buckling failure of the T-beam stem in the compression region at very high temperatures. The load ratio was the most critical design parameter, with the fire resistance times of the specimens being146min, 93min and 64min for load ratios of 0.3, 0.5 and 0.7 respectively. For the T-section, the temperature field of the flange plate was similar to that of a one-side fire exposed RC slab, and that of the web similar to that of a three-side fire exposed RC rectangular beam. Further numerical simulation results using steel reinforcement of 690MPa yield strength confirm that continuous, high strength steel reinforced concrete T-beams can be designed using plastic analysis
Interleukin-1β processing is dependent upon a calcium-mediated interaction with calmodulin.
No full textThe secretion of IL-1β is a central event in the initiation of inflammation. Unlike most other cytokines, the secretion of IL-1β requires two signals; one signal to induce the intracellular up-regulation of pro-IL-1β, and a second signal to drive secretion of the bioactive molecule. The release of pro-IL-1β is a complex process involving proteolytic cleavage by caspase-1. However, the exact mechanism of secretion is poorly understood. Here, we sought to identify novel proteins involved in IL-1β secretion and intracellular processing in order to gain further insight into the mechanism of IL-1 release. A human proteome microarray containing 19,951 unique proteins was used to identify proteins that bind human recombinant pro-IL-1β. Probes with a signal to noise ration of >3 were defined as relevant biologically. In these analyses, calmodulin was identified as a particularly strong hit, with a SNR of ~11. Using an ELISA-based protein-binding assay, the interaction of recombinant calmodulin with pro-IL-1β, but not mature IL-1β, was confirmed and shown to be calcium dependent. Finally, using small molecule inhibitors it was demonstrated that both calcium and calmodulin were required for nigericin induced IL-1β secretion in THP-1 cells and primary human monocytes. Together, these data suggest that following calcium influx into the cell, pro-IL-1β interacts with calmodulin and that this interaction is important for IL-1β processing and release