857 research outputs found

    Factors affecting internal standard selection for quantitative elemental bio-imaging of soft tissues by LA-ICP-MS

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    Element response variations under different laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) operating conditions were investigated to identify important factors for selecting an internal standard (IS) for quantitative elemental bio-imaging. Analytes covering a range of atomic masses and first ionisation potentials (FIP) were selected to investigate the signal response variation with changes in laser spot diameter, mass bias and cell sampling position. In all cases, an IS improved experimental precision regardless of a close match in element mass or FIP but optimal analyte/IS combinations depended on the difference in masses of the analyte and IS. Particular attention was paid to 13C as this isotope is typically used as an IS in elemental bio-imaging applications. Despite its non-ideal IS characteristics (often different mass and FIP to many analytes), possibility of abundance sensitivity effects and poor signal-to-background ratio, 13C was a suitable IS candidate exhibiting a linear response with respect to the mass ablated, apparent independence from the high abundance of the adjacent 14N mass peak and effective analyte normalisation after background subtraction as long as the 13C signal from the sample was at least 6% of the gross signal. © 2011 The Royal Society of Chemistry

    Are we there yet?:An update on transitional care in rheumatology

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    Abstract Significant progress has been made in the understanding of transitional care in rheumatology over the last few decades, yet universal implementation has not been realised and unmet needs continue to be reported. Possible explanations for this include lack of evidence as to which model is most effective; lack of attention to the multiple dimensions, stakeholders and systems involved in health transitions; and lack of consideration of the developmental appropriateness of transition interventions and the services/organisations/systems where such interventions are delivered. Successful transition has major implications to both the young people with juvenile-onset rheumatic disease and their families. Future research in this area will need to reflect both the multidimensional (biopsychosocial) and the multisystemic (multiple systems and stakeholders across personal/social/family support networks and health/social care/education systems). Only then will we be able to determine which aspects of transition readiness and service components influence which dimension. It is therefore imperative we continue to research and develop this area, involving both paediatric and adult rheumatology clinicians and researchers, remembering to look beyond both the condition and our discipline. Neither should we forget to tap into the exciting potential associated with digital technology to ensure further advances in transitional care are brought about in and beyond rheumatology

    Citizens observatories for effective Earth observations: the WeSenseIt approach

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    The WeSenseIt project defines citizen observatories as “A method, an environment and an infrastructure supporting an information ecosystem for communities and citizens, as well as emergency operators and policymakers, for discussion, monitoring and intervention on situations, places and events” . A collaborative approach has been taken to develop solutions that involve an exchange of information and expertise from all participants and where the focus is on arriving at practical solutions with a clear vision and direction. This has created a shared ownership scheme, and shifts power to the process itself rather than remaining within authorities, developers or decision-makers. The project’s emphasis is on delivering highly innovative technologies to support citizens, communities and authorities in developing a real-time situation awareness while ensuring all stakeholders play their part. Implementation has been through a combination of crowdsourcing, custom applications and dedicated web portals designed to foster collaboration, and which has created a shared knowledge base that facilitates decision-making processes and engages with communities. Data is captured via innovative sensors that are used directly by citizens, crowdsourcing from social networks (or by collective intelligence)

    An all-solid-state laser source at 671 nm for cold atom experiments with lithium

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    We present an all solid-state narrow line-width laser source emitting 670 mW670\,\mathrm{mW} output power at 671 nm671\,\mathrm{nm} delivered in a diffraction-limited beam. The \linebreak source is based on a fre-quency-doubled diode-end-linebreak pumped ring laser operating on the 4F3/2→4I13/2{^4F}_{3/2} \rightarrow {^4I}_{13/2} transition in Nd:YVO4_4. By using periodically-poled po-tassium titanyl phosphate (ppKTP) in an external build-up cavity, doubling efficiencies of up to 86% are obtained. Tunability of the source over 100 GHz100\,\rm GHz is accomplished. We demonstrate the suitability of this robust frequency-stabilized light source for laser cooling of lithium atoms. Finally a simplified design based on intra-cavity doubling is described and first results are presented

    Spheres of Practice for the Co-design of Wearables

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    As expectations within the area of smart textiles increasingly become informed and driven by technological developments, the disciplinary boundaries and relationship between user and technological innovation will unavoidably transform. The authors venture that new paradigms of collaborative practice will inevitably develop between design and science, to more fully realize both the opportunities and contexts that wearable textiles offer. Drawing on previous work by the authors namely Molecular Imprinted Textiles (MIT - 2009/10), Future Textile Visions (FTV - 2010/11), Design Specks: Connecting People with Speckled Computing (2012/13), Second Skin (2013/14), and The S*** Word: Designing the Empathic Underwardrobe (2014), a model is proposed to more clearly understand and navigate between design, technology and application, and more importantly, between our cultural understanding of the user and the wearer. This paper reflects on a series of projects that inform a methodological approach: a process of asking questions; developing scenarios; exploring materials and making; generating concepts and building prototypes. Each project involved collaborations between design, academics, users and industry, and a form of co-design, where knowledge exchange was central, design was the intermediary, and the goal was to understand the drivers and the stakeholders. Simultaneously, this research sought to better understand and communicate the development of more empathic textile and fashion artifacts, and solutions. Co-design in this context is seen as a core approach to shifting the balance from technology as merely adjunct, or as a hook for marketers and users, to a more informed and harmonised position, where technology sits proximally and comfortably. The notion of interdisciplinary understanding, which tracks across domains of product, fashion and textiles, presents an approach where the application is still emerging. Through analysis of this progressive series of projects, the authors suggest that there is an opportunity to explore the inherent connectedness that textiles might offer for the integration and embedding of technology within material as a means to embrace these affordance opportunities. Central to this notion is the realisation of opportunities arising from dialogue and collaborative making (i.e. co-design), and for exploring the transformative notions of the user and the wearer. This paper led the authors to pose a set of questions that align to a four stage design process: Research, Define, Develop, Reflect, to frame findings and insights, and to outline the potential for future opportunities of working with technology to achieve the making and wearing of desirable materializations on the body

    2009 pandemic influenza A(H1N1) virus in Scotland : geographically variable immunity in Spring 2010, following the winter outbreak

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    We determined the age- and location-specific seroprevalence of antibodies against 2009 pandemic influenza A(H1N1) virus in Scotland following the first two waves of infection. Serum samples collected following the winter outbreak were analysed by microneutralisation assay. The proportion of positive sera varied significantly between cities and, in the case of Inverness, between age groups (with younger adults more likely to be positive than older individuals). This study demonstrates that older people are no longer more likely to have antibodies against the virus than younger adults

    Is heart failure misdiagnosed in hospitalized patients with preserved ejection fraction? From the European Society of Cardiology - Heart Failure Association EURObservational Research Programme Heart Failure Long-Term Registry.

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    AIMS: In hospitalized patients with a clinical diagnosis of acute heart failure (HF) with preserved ejection fraction (HFpEF), the aims of this study were (i) to assess the proportion meeting the 2016 European Society of Cardiology (ESC) HFpEF criteria and (ii) to compare patients with restrictive/pseudonormal mitral inflow pattern (MIP) vs. patients with MIP other than restrictive/pseudonormal. METHODS AND RESULTS: We included hospitalized participants of the ESC-Heart Failure Association (HFA) EURObservational Research Programme (EORP) HF Long-Term Registry who had echocardiogram with ejection fraction (EF) ≄ 50% during index hospitalization. As no data on e', E/e' and left ventricular (LV) mass index were gathered in the registry, the 2016 ESC HFpEF definition was modified as follows: elevated B-type natriuretic peptide (BNP) (≄100 pg/mL for acute HF) and/or N-terminal pro-BNP (≄300 pg/mL) and at least one of the echocardiographic criteria: (i) presence of LV hypertrophy (yes/no), (ii) left atrial volume index (LAVI) of >34 mL/m2 ), or (iii) restrictive/pseudonormal MIP. Next, all patients were divided into four groups: (i) patients with restrictive/pseudonormal MIP on echocardiography [i.e. with presumably elevated left atrial (LA) pressure], (ii) patients with MIP other than restrictive/pseudonormal (i.e. with presumably normal LA pressure), (iii) atrial fibrillation (AF) group, and (iv) 'grey area' (no consistent description of MIP despite no report of AF). Of 6365 hospitalized patients, 1848 (29%) had EF ≄ 50%. Natriuretic peptides were assessed in 28%, LV hypertrophy in 92%, LAVI in 13%, and MIP in 67%. The 2016 ESC HFpEF criteria could be assessed in 27% of the 1848 patients and, if assessed, were met in 52%. Of the 1848 patients, 19% had restrictive/pseudonormal MIP, 43% had MIP other than restrictive/pseudonormal, 18% had AF and 20% were grey area. There were no differences in long-term all-cause or cardiovascular mortality, or all-cause hospitalizations or HF rehospitalizations between the four groups. Despite fewer non-cardiac comorbidities reported at baseline, patients with MIP other than restrictive/pseudonormal (i.e. with presumably normal LA pressure) had more non-cardiovascular (14.0 vs. 6.7 per 100 patient-years, P < 0.001) and cardiovascular non-HF (13.2 vs. 8.0 per 100 patient-years, P = 0.016) hospitalizations in long-term follow-up than patients with restrictive/pseudonormal MIP. CONCLUSIONS: Acute HFpEF diagnosis could be assessed (based on the 2016 ESC criteria) in only a quarter of patients and confirmed in half of these. When assessed, only one in three patients had restrictive/pseudonormal MIP suggestive of elevated LA pressure. Patients with MIP other than restrictive/pseudonormal (suggestive of normal LA pressure) could have been misdiagnosed with acute HFpEF or had echocardiography performed after normalization of LA pressure. They were more often hospitalized for non-HF reasons during follow-up. Symptoms suggestive of acute HFpEF may in some patients represent non-HF comorbidities

    Diquat Derivatives: Highly Active, Two-Dimensional Nonlinear Optical Chromophores with Potential Redox Switchability

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    In this article, we present a detailed study of structure−activity relationships in diquaternized 2,2â€Č-bipyridyl (diquat) derivatives. Sixteen new chromophores have been synthesized, with variations in the amino electron donor substituents, π-conjugated bridge, and alkyl diquaternizing unit. Our aim is to combine very large, two-dimensional (2D) quadratic nonlinear optical (NLO) responses with reversible redox chemistry. The chromophores have been characterized as their PF_6^− salts by using various techniques including electronic absorption spectroscopy and cyclic voltammetry. Their visible absorption spectra are dominated by intense π → π^* intramolecular charge-transfer (ICT) bands, and all show two reversible diquat-based reductions. First hyperpolarizabilities ÎČ have been measured by using hyper-Rayleigh scattering with an 800 nm laser, and Stark spectroscopy of the ICT bands affords estimated static first hyperpolarizabilities ÎČ_0. The directly and indirectly derived ÎČ values are large and increase with the extent of π-conjugation and electron donor strength. Extending the quaternizing alkyl linkage always increases the ICT energy and decreases the E_(1/2) values for diquat reduction, but a compensating increase in the ICT intensity prevents significant decreases in Stark-based ÎČ_0 responses. Nine single-crystal X-ray structures have also been obtained. Time-dependent density functional theory clarifies the molecular electronic/optical properties, and finite field calculations agree with polarized HRS data in that the NLO responses of the disubstituted species are dominated by ‘off-diagonal’ ÎČ_(zyy) components. The most significant findings of these studies are: (i) ÎČ_0 values as much as 6 times that of the chromophore in the technologically important material (E)-4â€Č-(dimethylamino)-N-methyl-4-stilbazolium tosylate; (ii) reversible electrochemistry that offers potential for redox-switching of optical properties over multiple states; (iii) strongly 2D NLO responses that may be exploited for novel practical applications; (iv) a new polar material, suitable for bulk NLO behavior

    Sparse canonical correlation analysis for identifying, connecting and completing gene-expression networks

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    <p>Abstract</p> <p>Background</p> <p>We generalized penalized canonical correlation analysis for analyzing microarray gene-expression measurements for checking completeness of known metabolic pathways and identifying candidate genes for incorporation in the pathway. We used Wold's method for calculation of the canonical variates, and we applied ridge penalization to the regression of pathway genes on canonical variates of the non-pathway genes, and the elastic net to the regression of non-pathway genes on the canonical variates of the pathway genes.</p> <p>Results</p> <p>We performed a small simulation to illustrate the model's capability to identify new candidate genes to incorporate in the pathway: in our simulations it appeared that a gene was correctly identified if the correlation with the pathway genes was 0.3 or more. We applied the methods to a gene-expression microarray data set of 12, 209 genes measured in 45 patients with glioblastoma, and we considered genes to incorporate in the glioma-pathway: we identified more than 25 genes that correlated > 0.9 with canonical variates of the pathway genes.</p> <p>Conclusion</p> <p>We concluded that penalized canonical correlation analysis is a powerful tool to identify candidate genes in pathway analysis.</p
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