2,000 research outputs found

    Localized-Surface-Plasmon Enhanced the 357 nm Forward Emission from ZnMgO Films Capped by Pt Nanoparticles

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    The Pt nanoparticles (NPs), which posses the wider tunable localized-surface-plasmon (LSP) energy varying from deep ultraviolet to visible region depending on their morphology, were prepared by annealing Pt thin films with different initial mass-thicknesses. A sixfold enhancement of the 357 nm forward emission of ZnMgO was observed after capping with Pt NPs, which is due to the resonance coupling between the LSP of Pt NPs and the band-gap emission of ZnMgO. The other factors affecting the ultraviolet emission of ZnMgO, such as emission from Pt itself and light multi-scattering at the interface, were also discussed. These results indicate that Pt NPs can be used to enhance the ultraviolet emission through the LSP coupling for various wide band-gap semiconductors

    Digit-only sauropod pes trackways from China - evidence of swimming or a preservational phenomenon?

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    For more than 70 years unusual sauropod trackways have played a pivotal role in debates about the swimming ability of sauropods. Most claims that sauropods could swim have been based on manus-only or manus-dominated trackways. However none of these incomplete trackways has been entirely convincing, and most have proved to be taphonomic artifacts, either undertracks or the result of differential depth of penetration of manus and pes tracks, but otherwise showed the typical pattern of normal walking trackways. Here we report an assemblage of unusual sauropod tracks from the Lower Cretaceous Hekou Group of Gansu Province, northern China, characterized by the preservation of only the pes claw traces, that we interpret as having been left by walking, not buoyant or swimming, individuals. They are interpreted as the result of animals moving on a soft mud-silt substrate, projecting their claws deeply to register their traces on an underlying sand layer where they gained more grip during progression. Other sauropod walking trackways on the same surface with both pes and manus traces preserved, were probably left earlier on relatively firm substrates that predated the deposition of soft mud and silt . Presently, there is no convincing evidence of swimming sauropods from their trackways, which is not to say that sauropods did not swim at all

    Impact of picture archiving communication systems on rates of duplicate imaging: a before-after study

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    <p>Abstract</p> <p>Background</p> <p>Electronic health information systems, such as picture archiving communication systems (PACS), are commonly believed to reduce the need for duplicate testing. However, empirical data to support this belief are not available.</p> <p>Methods</p> <p>Before-after study using administrative claims data from the Ontario Health Insurance Plan to determine whether the introduction of PACS at 10 hospitals in the Thames Valley region of southwestern Ontario, Canada between June 2004 and December 2005 reduced the frequency of duplicate imaging examinations. The imaging modalities studied were: chest and abdominal X-ray; computed tomography of the abdomen/pelvis, head, and chest. The frequency of duplicate testing was examined at 3 different time frames: 7 days, 30 days, and 60 days after a given index test.</p> <p>Results</p> <p>Overall frequencies of duplicate imaging were: 2.7% within 7 days of an index imaging test, 6.7% within 30 days, and 9.8% within 60 days. Comparing the 12 months before and 12 months after PACS, absolute reductions in the frequency of duplicate X-rays using 7-day, 30-day, and 60-day time frames were: 0.2% (P = 0.01), 0.6% (P < 0.001), and 0.9% (P < 0.001), respectively. In contrast, there were absolute <it>increases </it>in the frequency of duplicate CT scans after PACS of 0.0% (P = 0.92), 0.5% (P = 0.01), and 0.5% (P = 0.01), respectively.</p> <p>Conclusion</p> <p>The frequency of duplicate imaging is relatively low and we did not find large reductions in duplicate imaging after the introduction of PACS. Independent evaluation of electronic medical systems should be conducted to confirm widely held beliefs of their potential benefits.</p

    The J-triplet Cooper pairing with magnetic dipolar interactions

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    Recently, cold atomic Fermi gases with the large magnetic dipolar interaction have been laser cooled down to quantum degeneracy. Different from electric-dipoles which are classic vectors, atomic magnetic dipoles are quantum-mechanical matrix operators proportional to the hyperfine-spin of atoms, thus provide rich opportunities to investigate exotic many-body physics. Furthermore, unlike anisotropic electric dipolar gases, unpolarized magnetic dipolar systems are isotropic under simultaneous spin-orbit rotation. These features give rise to a robust mechanism for a novel pairing symmetry: orbital p-wave (L=1) spin triplet (S=1) pairing with total angular momentum of the Cooper pair J=1. This pairing is markedly different from both the 3^3He-B phase in which J=0 and the 3^3He-AA phase in which JJ is not conserved. It is also different from the p-wave pairing in the single-component electric dipolar systems in which the spin degree of freedom is frozen

    Pulmonary Toxicity and Adjuvant Effect of Di-(2-exylhexyl) Phthalate in Ovalbumin-Immunized BALB/c Mice

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    BACKGROUND: Asthma is a complex pulmonary inflammatory disease, which is characterized by airway hyperresponsiveness, variable airflow obstruction and inflammation in the airways. The majority of asthma is allergic asthma, which is a disease caused by type I hypersensitivity mediated by IgE. Exposures to a number of environmental chemicals are suspected to lead to asthma, one such pollutant is di-(2-ethylheyl) phthalate (DEHP). DEHP is a manufactured chemical that is commonly added in plastic products to make them flexible. Epidemiological studies have revealed a positive association between DEHP exposure and asthma prevalence. METHODOLOGY/PRINCIPAL FINDINGS: The present study was aimed to determine the underlying role of DEHP exposure in airway reactivity, especially when combined with allergen exposure. The biomarkers include pulmonary histopathology, airway hyperresponsiveness (lung function), IgE, IL-4, IFN-γ and eosinophils. Healthy balb/c mice were randomly divided into eight exposure groups (n = 8 each): (1) saline control, (2) 30 µg/(kg•d) DEHP, (3) 300 µg/(kg•d) DEHP, (4) 3000 µg/(kg•d) DEHP, and (5) ovalbumin (OVA)-sensitized group, (6) OVA-combined with 30 µg/(kg•d) DEHP, (7) OVA-combined with 300 µg/(kg•d) DEHP, and (8) OVA-combined with 3000 µg/(kg•d) DEHP. Experimental tests were conducted after 52-day DEHP exposure and subsequently one week of challenge with aerosolized OVA. The principal findings include: (1) Strong postive associations exist between OVA-combined DEHP exposure and serum total IgE (T-IgE), as well as histological findings. These positive associations show a dose-dependent low dose sensitive effect of DEHP. (2) IL-4, eosinophil recruitment and lung function are also indicators for adjuvant effect of DEHP. CONCLUSIONS/SIGNIFICANCE: Our results suggest that except the significant changes of immunological and inflammatory biomarkers (T-IgE, IL-4, IFN-γ and eosinophils), the pulmonary histological (histopathological examination) and physiological (lung function) data also support that DEHP may promote and aggravate allergic asthma by adjuvant effect

    ‘All hands-on deck’, working together to develop UK standards for public involvement in research

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    Background: Public involvement in research is an established part of the research process in the UK, however there remain questions about what good public involvement in research looks and feels like. Until now public involvement practitioners, researchers and members of the public have looked for answers in examples shared across networks, published case studies, guidance and research articles. Pulling these strands together, the UK Standards for Public Involvement provides six statements (standards) about public involvement in research. They were produced by a partnership of organisations from Scotland, Northern Ireland, Wales and England with contributions from involvement practitioners, public partners, researchers and research funders. Main body: Each standard has reflective questions, which are designed to encourage standard users to use approaches and behaviours that improve involvement, over time. The standards are designed to be used as a practical tool, and reflect the agreed hallmarks of good public involvement in research for example, flexibility in approaches used, shared learning, and mutual respect. The standards development process is described from the initial idea and scoping, via the appraisal of existing standard sets and integration of values and principles in public involvement in research. The collaborative writing process of and consultation on the draft standard set is described, together with what changed as a result of feedback. The initiation of a year-long testing programme with forty participating research organisations, the experiential feedback and the resulting changes to the standards is summarised. Conclusion: This commentary paper describes, in some detail, a process to develop a set of six standards for public involvement in research in the UK. Producing a complex, national public involvement initiative is not without its challenges, and in supplementary material partnership members reflect on and share their experiences of standards development. The next phase of integration and implementation is explored with concluding comments from those that tested and helped improve the standards

    Seminal plasma as a source of prostate cancer peptide biomarker candidates for detection of indolent and advanced disease

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    Background:Extensive prostate specific antigen screening for prostate cancer generates a high number of unnecessary biopsies and over-treatment due to insufficient differentiation between indolent and aggressive tumours. We hypothesized that seminal plasma is a robust source of novel prostate cancer (PCa) biomarkers with the potential to improve primary diagnosis of and to distinguish advanced from indolent disease. &lt;br&gt;Methodology/Principal Findings: In an open-label case/control study 125 patients (70 PCa, 21 benign prostate hyperplasia, 25 chronic prostatitis, 9 healthy controls) were enrolled in 3 centres. Biomarker panels a) for PCa diagnosis (comparison of PCa patients versus benign controls) and b) for advanced disease (comparison of patients with post surgery Gleason score &#60;7 versus Gleason score &#62;&gt;7) were sought. Independent cohorts were used for proteomic biomarker discovery and testing the performance of the identified biomarker profiles. Seminal plasma was profiled using capillary electrophoresis mass spectrometry. Pre-analytical stability and analytical precision of the proteome analysis were determined. Support vector machine learning was used for classification. Stepwise application of two biomarker signatures with 21 and 5 biomarkers provided 83% sensitivity and 67% specificity for PCa detection in a test set of samples. A panel of 11 biomarkers for advanced disease discriminated between patients with Gleason score 7 and organ-confined (&#60;pT3a) or advanced (&#8805;pT3a) disease with 80% sensitivity and 82% specificity in a preliminary validation setting. Seminal profiles showed excellent pre-analytical stability. Eight biomarkers were identified as fragments of N-acetyllactosaminide beta-1,3-N-acetylglucosaminyltransferase​,prostatic acid phosphatase, stabilin-2, GTPase IMAP family member 6, semenogelin-1 and -2. Restricted sample size was the major limitation of the study.&lt;/br&gt; &lt;br&gt;Conclusions/Significance: Seminal plasma represents a robust source of potential peptide makers for primary PCa diagnosis. Our findings warrant further prospective validation to confirm the diagnostic potential of identified seminal biomarker candidates.&lt;/br&gt

    On the Morphology, Structure and Field Emission Properties of Silver-Tetracyanoquinodimethane Nanostructures

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    Silver-tetracyanoquinodimethane(Ag-TCNQ) nanostructured arrays with different morphologies were grown by an organic vapor-transport reaction under different conditions. The field emission properties of nanostructured arrays were studied systematically. Their morphology and crystal structure were characterized by SEM and XRD, respectively. It was found that the field emission properties were strongly dependent on the reaction temperature and the initial Ag film thickness. The lowest turn-on field with 10-nm-thick silver film is about 2.0 V/μm, comparable to that of carbon nanotubes. The film crystal structure and the morphology are contributed to the final emission performance
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