680 research outputs found

    Consumer preferences for teledermoscopy screening to detect melanoma early

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    Introduction: ‘Store and forward’ teledermoscopy is a technology with potential advantages for melanoma screening. Any large-scale implementation of this technology is dependent on consumer acceptance. Aim: To investigate preferences for melanoma screening options compared with skin self-examination in adults considered to be at increased risk of developing skin cancer. Methods: A discrete choice experiment was completed by 35 consumers, all of whom had prior experience with the use of teledermoscopy, in Queensland, Australia. Participants made 12 choices between screening alternatives described by seven attributes including monetary cost. A mixed logit model was used to estimate the relative weights that consumers place on different aspects of screening, along with the marginal willingness to pay for teledermoscopy as opposed to screening at a clinic. Results: Overall, participants preferred screening/diagnosis by a health professional rather than skin self-examination. Key drivers of screening choice were for results to be reviewed by a dermatologist; a higher detection rate; fewer non-cancerous moles being removed in relation to every skin cancer detected; and less time spent away from usual activities. On average, participants were willing to pay AUD110 to have teledermoscopy with dermatologist review available to them as a screening option. Discussion and conclusions: Consumers preferentially value aspects of care that are more feasible with a teledermoscopy screening model, as compared with other skin cancer screening and diagnosis options. This study adds to previous literature in the area which has relied on the use of consumer satisfaction scales to assess the acceptability of teledermoscopy

    Ions in solution: Density Corrected Density Functional Theory (DC-DFT)

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    Standard density functional approximations often give questionable results for odd-electron radical complexes, with the error typically attributed to self-interaction. In density corrected density functional theory (DC-DFT), certain classes of density functional theory calculations are significantly improved by using densities more accurate than the self-consistent densities. We discuss how to identify such cases, and how DC-DFT applies more generally. To illustrate, we calculate potential energy surfaces of HO\cdotCl^- and HO\cdotH2_2O complexes using various common approximate functionals, with and without this density correction. Commonly used approximations yield wrongly shaped surfaces and/or incorrect minima when calculated self consistently, while yielding almost identical shapes and minima when density corrected. This improvement is retained even in the presence of implicit solvent

    Shallow genetic divergence indicates a Congo–Nile riverine connection for the softshell turtle Trionyx triunguis

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    WOS: 000288389500022We sequenced 20 new, field-collected individuals for up to seven genes to explore the phylogeography and conservation genetics of the threatened Nile softshell turtle Trionyx triunguis, including the first known-locality specimen from sub-Saharan Africa. Samples from Cameroon (West Africa), the Mediterranean and Nile River differed by at most a single nucleotide per gene, indicating the potential for a recent connection between these currently disjunct populations via the Nile-Congo River systems. Recently reported mitochondrial diversity between Mediterranean and "sub-Saharan" samples of the Nile softshell indicate that significant divergence exists across the species' range, but that variation cannot be fully incorporated into our analysis since those samples lack specific locality data.Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK); NSFNational Science Foundation (NSF) [DEB 0817042]; UC Davis Agricultural Experiment StationDwight Lawson collected the Cameroon turtle, and the San Diego Zoo provided a blood sample for our work, Permits were granted from the Republic of Turkey Ministry of Environment and Forestry. This work was supported by a grant from The Scientific and Technological Research Council of Turkey (TUBITAK), NSF grant DEB 0817042 and the UC Davis Agricultural Experiment Station. We thank Bob Thomson and members of the Shaffer lab for discussion. This study is a part of Muge Gidis's Ph.D. thesis

    Assessing what is needed to resolve a molecular phylogeny: simulations and empirical data from emydid turtles

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    <p>Abstract</p> <p>Background</p> <p>Phylogenies often contain both well-supported and poorly supported nodes. Determining how much additional data might be required to eventually recover most or all nodes with high support is an important pragmatic goal, and simulations have been used to examine this question. Most simulations have been based on few empirical loci, and suggest that well supported phylogenies can be determined with a very modest amount of data. Here we report the results of an empirical phylogenetic analysis of all 10 genera and 25 of 48 species of the new world pond turtles (family Emydidae) based on one mitochondrial (1070 base pairs) and seven nuclear loci (5961 base pairs), and a more biologically realistic simulation analysis incorporating variation among gene trees, aimed at determining how much more data might be necessary to recover weakly-supported nodes with strong support.</p> <p>Results</p> <p>Our mitochondrial-based phylogeny was well resolved, and congruent with some previous mitochondrial results. For example, all genera, and all species except <it>Pseudemys concinna</it>, <it>P. peninsularis</it>, and <it>Terrapene carolina </it>were monophyletic with strong support from at least one analytical method. The Emydinae was recovered as monophyletic, but the Deirochelyinae was not. Based on nuclear data, all genera were monophyletic with strong support except <it>Trachemys</it>, and all species except <it>Graptemys pseudogeographica</it>, <it>P. concinna</it>, <it>T. carolina</it>, and <it>T. coahuila </it>were monophyletic, generally with strong support. However, the branches subtending most genera were relatively short, and intergeneric relationships within subfamilies were mostly unsupported.</p> <p>Our simulations showed that relatively high bootstrap support values (i.e. ≥ 70) for all nodes were reached in all datasets, but an increase in data did not necessarily equate to an increase in support values. However, simulations based on a single empirical locus reached higher overall levels of support with less data than did the simulations that were based on all seven empirical nuclear loci, and symmetric tree distances were much lower for single versus multiple gene simulation analyses.</p> <p>Conclusion</p> <p>Our empirical results provide new insights into the phylogenetics of the Emydidae, but the short branches recovered deep in the tree also indicate the need for additional work on this clade to recover all intergeneric relationships with confidence and to delimit species for some problematic groups. Our simulation results suggest that moderate (in the few-to-tens of kb range) amounts of data are necessary to recover most emydid relationships with high support values. They also suggest that previous simulations that do not incorporate among-gene tree topological variance probably underestimate the amount of data needed to recover well supported phylogenies.</p

    Carbon nanotube electroactive polymer materials: opportunities and challenges

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    Carbon nanotubes (CNTs) with macroscopically ordered structures (e.g., aligned or patterned mats, fibers, and sheets) and associated large surface areas have proven promising as new CNT electroactive polymer materials (CNT-EAPs) for the development of advanced chemical and biological sensors. The functionalization of CNTs with many biological species to gain specific surface characteristics and to facilitate electron transfer to and from them for chemical- and bio-sensing applications is an area of intense research activity. Mechanical actuation generated by CNT-EAPs is another exciting electroactive function provided by these versatile materials. Controlled mechanical deformation for actuation has been demonstrated in CNT mats, fibers, sheets, and individual nanotubes. This article summarizes the current status and technological challenges for the development of electrochemical sensors and electromechanical actuators based on carbon nanotube electroactive materials

    A Real-Time Ultrasonic Imaging System (ARIS) for Manual Inspection of Aircraft Composite Structures

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    Inspection of aircraft composite structures at field site facilities (air bases) is routinely performed using manual ultrasonic testing (UT) techniques. Using these techniques, the examiner detects and sizes defects such as disbonds and delaminations by monitoring and interpreting A-scan waveform signals on a UT instrument display screen. Manual probe manipula- tion permits maximum scanning flexibility and optimization of the ultrasonic signal response by the examiner using manual motions not possible with mechanized scanners. However, the examiner also must be responsible for instrument calibration, signal interpretation, documentation of inspection results, and completeness of coverage. The data reviewer must be able to validate instrument calibration and completeness of coverage, confirm signal interpretation, and compare current UT results to those obtained during previous inspections

    The dietary isothiocyanate sulforaphane modulates gene expression and alternative gene splicing in a PTEN null preclinical murine model of prostate cancer

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    <p>Abstract</p> <p>Background</p> <p>Dietary or therapeutic interventions to counteract the loss of PTEN expression could contribute to the prevention of prostate carcinogenesis or reduce the rate of cancer progression. In this study, we investigate the interaction between sulforaphane, a dietary isothiocyanate derived from broccoli, PTEN expression and gene expression in pre malignant prostate tissue.</p> <p>Results</p> <p>We initially describe heterogeneity in expression of PTEN in non-malignant prostate tissue of men deemed to be at risk of prostate cancer. We subsequently use the mouse prostate-specific PTEN deletion model, to show that sulforaphane suppresses transcriptional changes induced by PTEN deletion and induces additional changes in gene expression associated with cell cycle arrest and apoptosis in PTEN null tissue, but has no effect on transcription in wild type tissue. Comparative analyses of changes in gene expression in mouse and human prostate tissue indicate that similar changes can be induced in humans with a broccoli-rich diet. Global analyses of exon expression demonstrated that sulforaphane interacts with PTEN deletion to modulate alternative gene splicing, illustrated through a more detailed analysis of DMBT1 splicing.</p> <p>Conclusion</p> <p>To our knowledge, this is the first report of how diet may perturb changes in transcription induced by PTEN deletion, and the effects of diet on global patterns of alternative gene splicing. The study exemplifies the complex interaction between diet, genotype and gene expression, and the multiple modes of action of small bioactive dietary components.</p

    Final Report on the Consequences of LHC Civil Engineering for the SPS and LEP

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    The excavation of the shafts and caverns for the ATLAS and CMS experiments and the transfer lines between the SPS and LHC will start whilst LEP and the SPS are running. This will be during a period when LEP should be at its peak performance and the SPS will be providing beams for LEP, fixed target physics and LHC test beams. Simulations show that movements of the machine tunnels can be expected during the excavation and it is essential that this does not affect the performance of the SPS and LEP. The predicted movements are of sufficient amplitude to prevent machine operation if no precautions are taken. This report contains the conclusions of the working group which has been studying these problems
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