8,430 research outputs found

    Portable Device for Continuous Sensing with Rapidly Pulsed LEDs – Part 1: Rapid On-the-fly Processing of Large Data Streams using an Open Source Microcontroller with Field Programmable Gate Array

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    We designed a portable system using an open source microcontroller (μC) with built-in field programmable gate array (FPGA) for on-the-fly data acquisition and processing of optical data generated from rapidly pulsed infrared light emitting diodes (IR LEDs) for optical sensing of gases. The system is used for rapid pulse generation (ca. 2 μs short pulses with a typical repetition rate of 1 kHz) to drive the IR LED, as well as for the optical sensing data acquisition and processing on-thefly large data streams of ca. 2 Gbit/s. The flexibility and performance of the system is demonstrated. Each of the digitally processed signal pulses yielded one data point of analytical signal in time as a quasi-continuous data stream produced at a rate of between 1000 and 0.1 Hz. This microcontroller-based portable open source platform is then implemented in on-the-fly data acquisition and processing, of analytical signals enabling continuous gas sensing

    Proof of concept study of a novel pacemapping algorithm as a basis to guide ablation of ventricular arrhythmias.

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    Aims: To determine if a software algorithm can use an individualized distance-morphology difference model, built from three initial pacemaps, to prospectively locate the exit site (ES) of ventricular arrhythmias (VA). Methods and results: Consecutive patients undergoing ablation of VA from a single centre were recruited. During mapping, three initial pacing points were collected in the chamber of interest and the navigation algorithm applied to predict the ES, which was corroborated by conventional mapping techniques. Thirty-two patients underwent ES prediction over 35 procedures. Structural heart disease was present in 16 (7 ischaemic cardiomyopathy, 9 non-ischaemic cardiomyopathy), median ejection fraction 45% [Interquartile range (IQR) 26]. The remainder had normal hearts. The navigation algorithm was applied to 46 VA (24 left ventricle, 11 right ventricular outflow tract, 5 left ventricular outflow tract, 4 right ventricle, 2 epicardial) and successfully located the site of best pacemap match in 45 within a median area of 196.5 mm2 (IQR 161.3, range 46.6-1288.2 mm2). Conclusions: In a diverse population of patients with and without structural heart disease, the ES of VA can be accurately and reliably identified to within a clinically useful target area using a simple software navigation algorithm based on pacemapping

    Engaging Undergraduates in Science Research: Not Just About Faculty Willingness.

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    Despite the many benefits of involving undergraduates in research and the growing number of undergraduate research programs, few scholars have investigated the factors that affect faculty members' decisions to involve undergraduates in their research projects. We investigated the individual factors and institutional contexts that predict faculty members' likelihood of engaging undergraduates in their research project(s). Using data from the Higher Education Research Institute's 2007-2008 Faculty Survey, we employ hierarchical generalized linear modeling to analyze data from 4,832 science, technology, engineering, and mathematics (STEM) faculty across 194 institutions to examine how organizational citizenship behavior theory and social exchange theory relate to mentoring students in research. Key findings show that faculty who work in the life sciences and those who receive government funding for their research are more likely to involve undergraduates in their research project(s). In addition, faculty at liberal arts or historically Black colleges are significantly more likely to involve undergraduate students in research. Implications for advancing undergraduate research opportunities are discussed

    Therapeutic Breast Reconstruction Using Gene Therapy–Delivered IFNγ Immunotherapy

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    After mastectomy, breast reconstruction is increasingly performed using autologous tissue with the aim of improving quality of life. During this procedure, autologous tissue is excised, relocated, and reattached using vascular anastomoses at the site of the extirpated breast. The period during which the tissue is ex vivo may allow genetic modification without any systemic exposure to the vector. Could such access be used to deliver therapeutic agents using the tissue flap as a vehicle? Such delivery may be more efficient than systemic treatment, in terms of oncological outcomes. The cytokine interferon gamma (IFNγ) has antitumor effects, but systemic toxicity that could be circumvented if its effect can be localized by delivery of the IFNγ gene via gene therapy to autologous tissue used for breast reconstruction, which then releases IFNγ and exerts anti-tumor effects. In a rat model of loco-regional recurrence (LRR) using both MADB-106-Luc and MAD-MB-231-Luc breast cancer cells, autologous tissue was transduced ex vivo with an adeno-associated viral vector (AAV) encoding IFNγ. The therapeutic reconstruction released IFNγ at the LRR site and eliminated cancer cells, significantly decreased tumor burden (P<0.05), and increased survival by 33% (P<0.05) compared to sham reconstruction. Mechanistically, localized IFNγ immunotherapy stimulated M1 macrophages to target cancer cells within the regional confines of the modified tumor environment. This concept of therapeutic breast reconstruction using ex vivo gene therapy of autologous tissue offers a new application for immunotherapy in breast cancer with a dual therapeutic effect of both reconstructing the ablative defect and delivering local adjuvant immunotherapy

    Matched sizes of activating and inhibitory receptor/ligand pairs are required for optimal signal integration by human Natural Killer cells

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    It has been suggested that receptor-ligand complexes segregate or co-localise within immune synapses according to their size, and this is important for receptor signaling. Here, we set out to test the importance of receptor-ligand complex dimensions for immune surveillance of target cells by human Natural Killer (NK) cells. NK cell activation is regulated by integrating signals from activating receptors, such as NKG2D, and inhibitory receptors, such as KIR2DL1. Elongating the NKG2D ligand MICA reduced its ability to trigger NK cell activation. Conversely, elongation of KIR2DL1 ligand HLA-C reduced its ability to inhibit NK cells. Whereas normal-sized HLA-C was most effective at inhibiting activation by normal-length MICA, only elongated HLA-C could inhibit activation by elongated MICA. Moreover, HLA-C and MICA that were matched in size co-localised, whereas HLA-C and MICA that were different in size were segregated. These results demonstrate that receptor-ligand dimensions are important in NK cell recognition, and suggest that optimal integration of activating and inhibitory receptor signals requires the receptor-ligand complexes to have similar dimensions

    Equality of Participation Online Versus Face to Face: Condensed Analysis of the Community Forum Deliberative Methods Demonstration

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    Online deliberation may provide a more cost-effective and/or less inhibiting environment for public participation than face to face (F2F). But do online methods bias participation toward certain individuals or groups? We compare F2F versus online participation in an experiment affording within-participants and cross-modal comparisons. For English speakers required to have Internet access as a condition of participation, we find no negative effects of online modes on equality of participation (EoP) related to gender, age, or educational level. Asynchronous online discussion appears to improve EoP for gender relative to F2F. Data suggest a dampening effect of online environments on black participants, as well as amplification for whites. Synchronous online voice communication EoP is on par with F2F across individuals. But individual-level EoP is much lower in the online forum, and greater online forum participation predicts greater F2F participation for individuals. Measured rates of participation are compared to self-reported experiences, and other findings are discussed.Comment: 14 pages, 10 tables, to appear in Efthimios Tambouris, Panos Panagiotopoulos, {\O}ystein S{\ae}b{\o}, Konstantinos Tarabanis, Michela Milano, Theresa Pardo, and Maria Wimmer (Editors), Electronic Participation: Proceedings of the 7th IFIP WG 8.5 International Conference, ePart 2015 (Thessaloniki, August 30-September 2), Springer LNCS Vol. 9249, 201

    A predictive model of users’ behavior and values of smart energy meters using PLS-SEM

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    © Springer Nature Switzerland AG 2020. A smart energy metering system is an IoT device that connects several electrical household devices and record, monitor, estimate, control in-house energy consumption in a real-time basis. Although smart energy meters have great capabilities, this technology is still in infancy stages in many developing countries, and little is known about what perceived values are associated with smart meters from residents’ perspectives. Therefore, this research aimed to fill this gap by examining the impact of six different types of perceived values on residents’ intentions to use smart meters in UAE. The study followed a quantitative approach by gathering 266 survey responses which were tested by using Partial Least Squares-Structural Equation Modeling (PLS-SEM). The statistical results genuinely indicated that perceived epistemic values, environmental values, emotional values, and convenience values can significantly impact residents’ intention to use smart meter, whereas social values and monetary values found to have no significant impact on their intentions to use this technology. Theoretical and practical implications are indicated, and directions of future research are specified afterwards
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