In recent times regulatory pressure to reduce CO 2 emissions has driven research towards looking at blending fossil fuels with alternatives such as crop-produced alcohols. The alcohol of interest in this paper is ethanol and it was studied in mixtures with gasoline and iso-octane in an optical sparkignition engine, running at 1500 RPM at low-load operation with 0.5 bar absolute intake plenum pressure. Specifically, tests involved fuels of 100% gasoline and 100% iso-octane, so that differences between multi and single-component fuels could be compared within this environment. A mixture of 25% ethanol with 75% iso-octane was also tested and compared. Finally, mixtures of highpercentage of ethanol (85% ethanol) in gasoline and in iso-octane were used in the study and compared. Tests were undertaken using a standard port injection system as well as a direct injection system so an appraisal of both mixture preparation methods could be made. Initially, a high-speed imaging study of the in-cylinder spray formation was undertaken with the direct injection system for different injection timings and engine-head temperatures under motoring engine conditions. The engine was also run with continuous firing using all fuels. In-cylinder pressure data were collected at 0.2° crank angle resolution for each cycle and synchronized with simultaneous high-speed flame imaging at 1° crank angle resolution for a series of 100 consecutive cycles for all test points. The flame images were processed to quantify the evolution of an equivalent flame radius.

No abstract

The Engineering Meetings Board has approved this paper for publication. It has successfully completed SAE's peer review process under the supervision of the session organizer. This process requires a minimum of three (3) reviews by industry experts. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of SAE. ISSN 0148-7191 Positions and opinions advanced in this paper are those of the author(s) and not necessarily those of SAE. The author is solely responsible for the content of the paper. SAE ABSTRACTThis experimental work was concerned with the combination of internal EGR with an early inlet valve closure strategy for improved part-load fuel economy. The experiments were performed in a new spark-ignited thermodynamic single cylinder research engine, equipped with a mechanical fully variable valvetrain on both the inlet and exhaust. During unthrottled operation at constant engine speed and load, increasing the mass of trapped residual allowed increased valve duration and lift to be used. In turn, this enabled further small improvements in gas exchange efficiency, thermal efficiency and hence indicated fuel consumption. Such effects were quantified under both port and homogeneous central direct fuel injection conditions. Shrouding of the inlet ports as a potential method to increase in-cylinder gas velocities has also been considered.

This work involved study of the effects of alcohol blends on combustion, fuel economy and emissions in a single cylinder research engine equipped with a mechanical fully variable valvetrain on the inlet and variable valve timing on the exhaust. A number of splash blends of gasoline, iso-octane, ethanol and butanol were examined during port fuel injected early inlet valve closing operation, both with and without variable valve timing. Under low valve overlap conditions, it was apparent that the inlet valve durations/lifts required for full unthrottled operation were remarkably similar for the wide range of blends studied. However, with high valve overlap differences in burning velocities and internal EGR tolerances warranted changes in these valve settings. In turn, it was concluded that high ethanol content blends facilitated minimum throttling at the inlet valve itself and the largest relative savings in terms of fuel consumption, engine-out emissions of NOx and (corrected) unburned hydrocarbons.

We have previously shown that KIT protein expression in the gastrointestinal tumour (GIST) cell line GIST882 can be down-regulated using a small molecule approach that targets expression at the transcriptional level. The small-molecule naphthalene diimide derivative ND1 developed as a G-quadruplex telomere targeting agent can inhibit telomerase activity and can also reduce c-kit mRNA levels, consistent with a dual G-quadruplex mechanism of action in this cell line. An Imatinib (Gleevec) resistant patient-derived cell line GIST48 expresses high levels of the anti-apoptotic protein bcl-2. The compound ND1 down-regulates the expression of bcl-2 in this resistant cell line, while having no discernable effect on c-kit protein expression levels or telomerase activity, both associated with DNA quadruplex stabilization. Instead we observe that translation of the apoptosis-related protein is impeded, while mRNA levels remain unaffected. The identification of a G-rich quadruplex-forming sequence in the 5’-UTR region of the bcl-2 gene, upstream of the translation start site, lead us to the development of a dual luciferase reporter assay. Utilizing a psiCHECK-2 vector we inserted the G-rich 67 base pair bcl-2 5’-UTR gene sequence upstream of the Renilla luciferase start codon. In vitro experiments have shown that the G-rich sequence can form a stable RNA G-quadruplex and interfere with translation. Our in vivo transfection experiments with ND1 in a GIST cell line shows concentration-dependent inhibition of bcl-2 protein expression. RNA G-quadruplex formation and ligand stabilization may thus be a novel anti-cancer route for the down-regulation of the anti-apoptotic protein bcl-2 in chemo-resistant cancers. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2310. doi:10.1158/1538-7445.AM2011-2310