112 research outputs found
Thiazole-induced rigidification in substituted dithieno-tetrathiafulvalene : the effect of planarisation on charge transport properties
Two novel tetrathiafulvalene (TTF) containing compounds 1 and 2 have been synthesised via a four-fold Stille coupling between a tetrabromo-dithienoTTF 5 and stannylated thiophene 6 or thiazole 4. The optical and electrochemical properties of compounds 1 and 2 have been measured by UV-vis spectroscopy and cyclic voltammetry and the results compared with density functional theory (DFT) calculations to confirm the observed properties. Organic field effect transistor (OFET) devices fabricated from 1 and 2 demonstrated that the substitution of thiophene units for thiazoles was found to increase the observed charge transport, which is attributed to induced planarity through S-N interactions of adjacent thiazole nitrogen atoms and TTF sulfur atoms and better packing in the bulk
RjeÄnik hrvatskoga ili srpskoga jezika dovrĆĄen
Simple protocols have been devised for peroxyoxalate chemiluminescence demonstrations that use ureaâhydrogen peroxide or sodium percarbonate as oxidants in place of aqueous solutions of hydrogen peroxide. The procedures described are compatible with well-known peroxyoxalates and fluorescers and have been found to be convenient for use for outreach activities in venues with limited laboratory facilities.PostprintPeer reviewe
Determination of the Piezoelectric Field in InGaN Quantum Wells
In many studies, the value of the experimentally determined internal piezoelectric field has been reported to be significantly smaller than theoretical values. We believe this is due to an inappropriate approximation for the electric field within the depletion region, which is used in the analysis of experimental data, and we propose an alternative method. Using this alternative, we have measured the strength of the internal field of InGaN p-i-n structures, using reverse bias photocurrent absorption spectroscopy and by fitting the bias dependent peak energy using microscopic theory based on the screened Hartree-Fock approximation. The results agree with those using material constants interpolated from binary values
Engineers and planners: Sustainable water management alliances
Copyright © 2011 ICE Publishing Ltd. Permission is granted by ICE Publishing to print one copy for personal use. Any other use of these PDF files is subject to reprint fees.In the future, increasing pressure will inevitably be placed on the spatial planning system to improve its consideration of water management issues. Emerging challenges include designing for climatic extremes, reducing flood risk, managing increasingly scarce water resources and improving water quality. These issues need to be balanced with a range of other spatial planning priorities and objectives, including meeting new housing needs, facilitating economic growth, and creating and maintaining quality places. The sheer complexity of the issues surrounding water management and the impacts upon spatial planning mean that partnership working is essential to achieve an integrated approach. Planners need the expertise, and crucially the understanding, of engineers and hydrologists.
However, there can be considerable misunderstanding and miscommunication between disciplines, often concerning the institutional context in which the various parties operate. A plethora of policies, tools and assessments exist, which can make integrated water management an overwhelming prospect for the planner. This paper attempts to identify and address some of the issues faced, as well as examining how planners embed hydrological issues in decision making and how engineers could better facilitate this
Australian clinical practice guidelines for the diagnosis and management of Barrett's esophagus and early esophageal adenocarcinoma
Author version made available following 12 month embargo from date of publication according to publisher copyright policy.Barrett's esophagus (BE), a common condition, is the only known precursor to esophageal adenocarcinoma (EAC). There is uncertainty about the best way to manage BE as most people with BE never develop EAC and most patients diagnosed with EAC have no preceding diagnosis of BE. Moreover, there have been recent advances in knowledge and practice about the management of BE and early EAC. To aid clinical decision making in this rapidly moving field, Cancer Council Australia convened an expert working party to identify pertinent clinical questions. The questions covered a wide range of topics including endoscopic and histological definitions of BE and early EAC; prevalence, incidence, natural history, and risk factors for BE; and methods for managing BE and early EAC. The latter considered modification of lifestyle factors; screening and surveillance strategies; and medical, endoscopic, and surgical interventions. To answer each question, the working party systematically reviewed the literature and developed a set of recommendations through consensus. Evidence underpinning each recommendation was rated according to quality and applicability
Exploring the predation of UK bumblebees (Apidae, Bombus spp.) by the invasive pitcher plant Sarracenia purpurea: examining the effects of annual variation, seasonal variation, plant density and bumblebee gender
Invasive carnivorous plant species can impact the native invertebrate communities on which they prey. This article explores the predation of native UK bumblebees (Bombus spp.) by the invasive pitcher plant species Sarracenia purpurea and discusses the potential effect of S. purpurea on native bumblebees. Specifically, it evaluates whether the extent to which bumblebees are captured varies (i) over successive years, (ii) across June and July, (iii) with density of distribution of pitchers or (iv) with bumblebee gender. Pitcher contents were examined from an established population of Sarracenia purpurea growing in Dorset, UK. Results show that the total extent to which bumblebees were captured differed over the years 2012â2014 inclusive. A 1-year study in 2013 showed that more bumblebees were caught in July than in June and more bumblebees were captured when pitchers grew at high density. Results from 2013 also showed that more pitchers caught more than one bumblebee than would be expected based on a normal probability distribution and that this phenomenon affects female and male bumblebees equally. We discuss possible reasons for these results including that the bumblebees may be using S. purpurea as a resource. Further work is required to establish the exact underpinning mechanisms and the relative roles of plant and bumblebee behaviour within the relationship. Such interaction complexity may have consequences for consideration in invasive carnivorous plant management
Developing cancer warning statements for alcoholic beverages
Background: There is growing evidence of the increased cancer risk associated with alcohol consumption, but this is not well understood by the general public. This study investigated the acceptability among drinkers of cancer warning statements for alcoholic beverages. Methods: Six focus groups were conducted with Australian drinkers to develop a series of cancer-related warning statements for alcohol products. Eleven cancer warning statements and one general health warning statement were subsequently tested on 2,168 drinkers via an online survey. The statements varied by message frame (positive vs negative), cancer reference (general vs specific), and the way causality was communicated (âincreases risk of cancerâ vs âcan cause cancerâ). Results: Overall, responses to the cancer statements were neutral to favorable, indicating that they are unlikely to encounter high levels of negative reaction from the community if introduced on alcoholic beverages. Females, younger respondents, and those with higher levels of education generally found the statements to be more believable, convincing, and personally relevant. Positively framed messages, those referring to specific forms of cancer, and those using âincreases risk of cancerâ performed better than negatively framed messages, those referring to cancer in general, and those using the term âcan cause cancerâ. Conclusion: Cancer warning statements on alcoholic beverages constitute a potential means of increasing awareness about the relationship between alcohol consumption and cancer risk
Comparative analysis of genome-wide association studies signals for lipids, diabetes, and coronary heart disease: Cardiovascular Biomarker Genetics Collaboration
To evaluate the associations of emergent genome-wide-association study-derived coronary heart disease (CHD)-associated single nucleotide polymorphisms (SNPs) with established and emerging risk factors, and the association of genome-wide-association study-derived lipid-associated SNPs with other risk factors and CHD events
Diversity analysis of cotton (Gossypium hirsutum L.) germplasm using the CottonSNP63K Array
Cotton germplasm resources contain beneficial alleles that can be exploited to develop germplasm adapted to emerging environmental and climate conditions. Accessions and lines have traditionally been characterized based on phenotypes, but phenotypic profiles are limited by the cost, time, and space required to make visual observations and measurements. With advances in molecular genetic methods, genotypic profiles are increasingly able to identify differences among accessions due to the larger number of genetic markers that can be measured. A combination of both methods would greatly enhance our ability to characterize germplasm resources. Recent efforts have culminated in the identification of sufficient SNP markers to establish high-throughput genotyping systems, such as the CottonSNP63K array, which enables a researcher to efficiently analyze large numbers of SNP markers and obtain highly repeatable results. In the current investigation, we have utilized the SNP array for analyzing genetic diversity primarily among cotton cultivars, making comparisons to SSR-based phylogenetic analyses, and identifying loci associated with seed nutritional traits. (Résumé d'auteur
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