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41.
Margherita Modesti Colleen Szeto Renata Ristic WenWen Jiang Julie Culbert Keren Bindon Cesare Catelli Fabio Mencarelli Pietro Tonutti Kerry Wilkinson 《Molecules (Basel, Switzerland)》2021,26(6)
When bushfires occur near grape growing regions, vineyards can be exposed to smoke, and depending on the timing and duration of grapevine smoke exposure, fruit can become tainted. Smoke-derived volatile compounds, including volatile phenols, can impart unpleasant smoky, ashy characters to wines made from smoke-affected grapes, leading to substantial revenue losses where wines are perceivably tainted. This study investigated the potential for post-harvest ozone treatment of smoke-affected grapes to mitigate the intensity of smoke taint in wine. Merlot grapevines were exposed to smoke at ~7 days post-veraison and at harvest grapes were treated with 1 or 3 ppm of gaseous ozone (for 24 or 12 h, respectively), prior to winemaking. The concentrations of smoke taint marker compounds (i.e., free and glycosylated volatile phenols) were measured in grapes and wines to determine to what extent ozonation could mitigate the effects of grapevine exposure to smoke. The 24 h 1 ppm ozone treatment not only gave significantly lower volatile phenol and volatile phenol glycoside concentrations but also diminished the sensory perception of smoke taint in wine. Post-harvest smoke and ozone treatment of grapes suggests that ozone works more effectively when smoke-derived volatile phenols are in their free (aglycone) form, rather than glycosylated forms. Nevertheless, the collective results demonstrate the efficacy of post-harvest ozone treatment as a strategy for mitigation of smoke taint in wine. 相似文献
42.
Calum Williams Yunuen Montelongo Jaime Oscar Tenorio‐Pearl Andrea Cabrero‐Vilatela Stephan Hofmann William I. Milne Timothy D. Wilkinson 《固体物理学:研究快报》2015,9(2):125-129
Digital holography requires arrays of small reconfigurable elements to achieve complex reconstruction of the hologram with common systems based on pixels utilizing liquid crystal on silicon (LCoS) technology. The backplane of a typical pixel element is potentially underutilized and thus relatively large physical areas exist in which information can be stored and exploited to give additional functionality to pixel elements. Polarisation and wavelength dependent optical properties can be achieved in small areas using the plasmonic effects of optical antennae. The integration of LCs with optical antennae‐based plasmonic holograms allows active modulation of the far field pattern. The work here demonstrates the concept that conventional LCoS pixel elements can be greatly enhanced with the integration of plasmonic holograms, composed of optical antennae patterned on the surface, giving rise to new levels of modulation capability for holographic pixel elements. Using LCs, polarisation dependent effects in plasmonic holograms can be switched. ‘Engineered pixels', with sub‐wavelength multiplexing over both polarisation and wavelength, can increase the channel capacity of a typical LC display device. (© 2015 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) 相似文献
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Isabel V. L. Wilkinson Kelly J. Perkins Hannah Dugdale Lee Moir Aini Vuorinen Maria Chatzopoulou Sarah E. Squire Sebastian Monecke Alexander Lomow Marcus Geese Philip D. Charles Peter Burch Jonathan M. Tinsley Graham M. Wynne Stephen G. Davies Francis X. Wilson Fraydoon Rastinejad Shabaz Mohammed Kay E. Davies Angela J. Russell 《Angewandte Chemie (International ed. in English)》2020,59(6):2420-2428
Duchenne muscular dystrophy (DMD) is a fatal muscle‐wasting disease arising from mutations in the dystrophin gene. Upregulation of utrophin to compensate for the missing dystrophin offers a potential therapy independent of patient genotype. The first‐in‐class utrophin modulator ezutromid/SMT C1100 was developed from a phenotypic screen through to a Phase 2 clinical trial. Promising efficacy and evidence of target engagement was observed in DMD patients after 24 weeks of treatment, however trial endpoints were not met after 48 weeks. The objective of this study was to understand the mechanism of action of ezutromid which could explain the lack of sustained efficacy and help development of new generations of utrophin modulators. Using chemical proteomics and phenotypic profiling we show that the aryl hydrocarbon receptor (AhR) is a target of ezutromid. Several lines of evidence demonstrate that ezutromid binds AhR with an apparent KD of 50 nm and behaves as an AhR antagonist. Furthermore, other reported AhR antagonists also upregulate utrophin, showing that this pathway, which is currently being explored in other clinical applications including oncology and rheumatoid arthritis, could also be exploited in future DMD therapies. 相似文献
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If an ex situ programme for the conservation of rare and threatened bryophytes is to succeed, a method of long-term, basal storage is required. The aim of this study was to determine the effectiveness of sucrose, ABA and sucrose/ABA combined, as cryoprotectant pretreatments, for the long-term storage of protonemata of the endangered Cornish path moss, Ditrichum cornubicum. This work is a prelude to the in vitro conservation of rare and endangered UK bryophytes. The addition of sucrose and/or ABA in the pre-culture medium, reduced protonemal growth rate. However, pretreatment afforded a high level of protection against tissue damage during dehydration and freezing, with 100 % regeneration of pretreated plants after thawing, compared to 53 % regeneration of controls. Sucrose combined with ABA in the pre-culture medium gave the most effective cryoprotection, with protonemata having fewer necrotic tissues and rapid recovery of growth. 相似文献
46.
Kwok W. Chiu David Lyons Geoffrey Wilkinson Mark Thornton-Pett Michael B. Hursthouse 《Polyhedron》1983,2(8):803-810
The reduction of WCl4(PMe3)3 by sodium amalgam in presence of phenylacetylene gives W(PMe3)(PhCCH)3 (A). Reduction in presence of methylisocyanide gives W(PMe3)2(MeNC)4 (B), while in presence of excess PMe3 in tetrahydrofuran under hydrogen, WH2Cl2(PMe3)4 (C) is formed. The reaction of WCl2(PMe3)4 with methanol in tetrahydrofuran gives mixtures of WH2Cl2(PMe3)4 and WOC12(PMe3)3 (D).The structures of A, B, and D have been determined by X-ray diffraction. 相似文献
47.
A numerical solution of the developing non-isothermal flow of a generalised power-law fluid in a slightly converging slit is presented, a problem which is relevance to some polymer processing operations.The results are presented in graphical form. They indicate that inertia forces and kinetic energy increases along the slit and these factors affect the development of the velocity and stress distributions. The effect of other parameters on the process is also brought out. 相似文献
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A theoretical and experimental study of heat transfer to polymer melts flowing through ducts is presented. The mathematical model provides for shear heating and expansion cooling effects for various wall boundary conditions.Experimental results, obtained in tube flow, show reproducible temperature and velocity profiles and the data confirm the predictions of the magnitude of the shear heating and expansion cooling effects.It is concluded that the method can be justified for predicting heat transfer in more complex geometries and some preliminary results are presented. 相似文献