64 research outputs found
Practice-centred approach to research in design
This paper gives an overview of practice-centred research programmes at Sheffield Hallam University and discusses the principles behind practice-centred research, its place in the Design School, its effect on the regional economy and the community and the resources and methods employed. Implications for research degrees are discussed and developments in the form of the PhD are described.</p
Knowledge and the artefact
This paper discusses ways that knowledge may be found in or through artefacts. One purpose is to suggest situations where artefacts might be central to a narrative, rather than secondary to a text. A second purpose is to suggest ways that design and production of artefacts might be instrumental in eliciting knowledge.
Four general situations are proposed:
(1) Simple Forms - an artefact demonstrates or describes a principle or technique.
(2) Communication of Process - artefacts arising from a process make the process explicit.
(3) Artefacts Within the Research - artefacts are instrumental in advancing the research by communicating ideas or information.
(4) Knowledge Elicited by Artefacts - artefacts provide a stimulus or context which enables information to be uncovered. .</p
On Beginning the Second Half Century
Observations on the 50th year of the Washington Law Review\u27s publication
Sendaway capillary NT-proBNP in pulmonary hypertension
\ua9 Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ. BACKGROUND: N-terminal pro-B-type natriuretic peptide (NT-proBNP) is a biomarker of cardiac ventricular wall stress that is incorporated into pulmonary hypertension (PH) risk stratification models. Sendaway sampling may enable patients to perform NT-proBNP tests remotely. This UK-wide study aimed to assess the agreement of sendaway NT-proBNP with standard venous NT-proBNP and to assess the effect of delayed processing. METHODS: Reference venous NT-proBNP was collected from PH patients. Samples for capillary and venous sendaway tests were collected contemporaneously, mailed to a reference laboratory and processed at 3 and 7 days using a Roche Cobas e411 device. Differences in paired measurements were analysed with Passing-Bablok regression, percentage difference plots and the % difference in risk strata. RESULTS: 113 patients were included in the study. 13% of day 3 capillary samples were insufficient. Day 3 capillary samples were not equivalent to reference samples (Passing Bablok analysis slope of 0.91 (95% CI 0.88 to 0.93) and intercept of 6.0 (95% CI 0.2 to 15.9)). The relative median difference was -7% and there were acceptable limits of agreement. Day 3 capillary NT-proBNP accurately risk stratified patients in 93.5% of cases. By comparison, day 3 venous results accurately risk stratified patients in 90.1% of cases and were equivalent by Passing-Bablok regression. Delayed sampling of sendaway tests led to an unacceptable level of agreement and systematically underestimated NT-proBNP. CONCLUSIONS: Sendaway NT-proBNP sampling may provide an objective measure of right ventricular strain for virtual PH clinics. Results must be interpreted with caution in cases of delayed sampling
LFI 30 and 44 GHz receivers Back-End Modules
The 30 and 44 GHz Back End Modules (BEM) for the Planck Low Frequency
Instrument are broadband receivers (20% relative bandwidth) working at room
temperature. The signals coming from the Front End Module are amplified, band
pass filtered and finally converted to DC by a detector diode. Each receiver
has two identical branches following the differential scheme of the Planck
radiometers. The BEM design is based on MMIC Low Noise Amplifiers using GaAs
P-HEMT devices, microstrip filters and Schottky diode detectors. Their
manufacturing development has included elegant breadboard prototypes and
finally qualification and flight model units. Electrical, mechanical and
environmental tests were carried out for the characterization and verification
of the manufactured BEMs. A description of the 30 and 44 GHz Back End Modules
of Planck-LFI radiometers is given, with details of the tests done to determine
their electrical and environmental performances. The electrical performances of
the 30 and 44 GHz Back End Modules: frequency response, effective bandwidth,
equivalent noise temperature, 1/f noise and linearity are presented
Gold–Oligonucleotide Nanoconstructs Engineered to Detect Conserved Enteroviral Nucleic Acid Sequences
Enteroviruses are ubiquitous mammalian pathogens that can produce mild to life-threatening disease. We developed a multimodal, rapid, accurate and economical point-of-care biosensor that can detect nucleic acid sequences conserved amongst 96% of all known enteroviruses. The biosensor harnesses the physicochemical properties of gold nanoparticles and oligonucleotides to provide colourimetric, spectroscopic and lateral flow-based identification of an exclusive enteroviral nucleic acid sequence (23 bases), which was identified through in silico screening. Oligonucleotides were designed to demonstrate specific complementarity towards the target enteroviral nucleic acid to produce aggregated gold–oligonucleotide nanoconstructs. The conserved target enteroviral nucleic acid sequence (≥1 × 10−7 M, ≥1.4 × 10−14 g/mL) initiates gold–oligonucleotide nanoconstruct disaggregation and a signal transduction mechanism, producing a colourimetric and spectroscopic blueshift (544 nm (purple) > 524 nm (red)). Furthermore, lateral-flow assays that utilise gold–oligonucleotide nanoconstructs were unaffected by contaminating human genomic DNA, demonstrated rapid detection of conserved target enteroviral nucleic acid sequence
Gold–Oligonucleotide Nanoconstructs Engineered to Detect Conserved Enteroviral Nucleic Acid Sequences
From MDPI via Jisc Publications RouterHistory: accepted 2021-07-07, pub-electronic 2021-07-14Publication status: PublishedFunder: Innovate UK; Grant(s): Partnership Number: 9971Funder: Engineering and Physical Sciences Research Council; Grant(s): EP/M027333/1, EP/P006485/1Funder: University of Nottingham; Grant(s): Nottingham Research FellowshipEnteroviruses are ubiquitous mammalian pathogens that can produce mild to life-threatening disease. We developed a multimodal, rapid, accurate and economical point-of-care biosensor that can detect nucleic acid sequences conserved amongst 96% of all known enteroviruses. The biosensor harnesses the physicochemical properties of gold nanoparticles and oligonucleotides to provide colourimetric, spectroscopic and lateral flow-based identification of an exclusive enteroviral nucleic acid sequence (23 bases), which was identified through in silico screening. Oligonucleotides were designed to demonstrate specific complementarity towards the target enteroviral nucleic acid to produce aggregated gold–oligonucleotide nanoconstructs. The conserved target enteroviral nucleic acid sequence (≥1 × 10−7 M, ≥1.4 × 10−14 g/mL) initiates gold–oligonucleotide nanoconstruct disaggregation and a signal transduction mechanism, producing a colourimetric and spectroscopic blueshift (544 nm (purple) > 524 nm (red)). Furthermore, lateral-flow assays that utilise gold–oligonucleotide nanoconstructs were unaffected by contaminating human genomic DNA, demonstrated rapid detection of conserved target enteroviral nucleic acid sequence (60 s), and could be interpreted with a bespoke software and hardware electronic interface. We anticipate that our methodology will translate in silico screening of nucleic acid databases to a tangible enteroviral desktop detector, which could be readily translated to related organisms. This will pave the way forward in the clinical evaluation of disease and complement existing strategies to overcome antimicrobial resistance
Thermal susceptibility of the Planck-LFI receivers
This paper is part of the Prelaunch status LFI papers published on JINST:
http://www.iop.org/EJ/journal/-page=extra.proc5/jinst .
This paper describes the impact of the Planck Low Frequency Instrument front
end physical temperature fluctuations on the output signal. The origin of
thermal instabilities in the instrument are discussed, and an analytical model
of their propagation and impact on the receivers signal is described. The
experimental test setup dedicated to evaluate these effects during the
instrument ground calibration is reported together with data analysis methods.
Finally, main results obtained are discussed and compared to the requirements.Comment: This is an author-created, un-copyedited version of an article
accepted for publication in Journal of Instrumentation. IOP Publishing Ltd is
not responsible for any errors or omissions in this version of the manuscript
or any version derived from it. The definitive publisher authenticated
version is available online at 10.1088/1748-0221/4/12/T1201
Design, development and verification of the 30 and 44 GHz front-end modules for the Planck Low Frequency Instrument
We give a description of the design, construction and testing of the 30 and
44 GHz Front End Modules (FEMs) for the Low Frequency Instrument (LFI) of the
Planck mission to be launched in 2009. The scientific requirements of the
mission determine the performance parameters to be met by the FEMs, including
their linear polarization characteristics.
The FEM design is that of a differential pseudo-correlation radiometer in
which the signal from the sky is compared with a 4-K blackbody load. The Low
Noise Amplifier (LNA) at the heart of the FEM is based on indium phosphide High
Electron Mobility Transistors (HEMTs). The radiometer incorporates a novel
phase-switch design which gives excellent amplitude and phase match across the
band.
The noise temperature requirements are met within the measurement errors at
the two frequencies. For the most sensitive LNAs, the noise temperature at the
band centre is 3 and 5 times the quantum limit at 30 and 44 GHz respectively.
For some of the FEMs, the noise temperature is still falling as the ambient
temperature is reduced to 20 K. Stability tests of the FEMs, including a
measurement of the 1/f knee frequency, also meet mission requirements.
The 30 and 44 GHz FEMs have met or bettered the mission requirements in all
critical aspects. The most sensitive LNAs have reached new limits of noise
temperature for HEMTs at their band centres. The FEMs have well-defined linear
polarization characteristcs.Comment: 39 pages, 33 figures (33 EPS files), 12 tables. Planck LFI technical
papers published by JINST:
http://www.iop.org/EJ/journal/-page=extra.proc5/1748-022
The linearity response of the Planck-LFI flight model receivers
In this paper we discuss the linearity response of the Planck-LFI receivers,
with particular reference to signal compression measured on the 30 and 44 GHz
channels. In the article we discuss the various sources of compression and
present a model that accurately describes data measured during tests performed
with individual radiomeric chains. After discussing test results we present the
best parameter set representing the receiver response and discuss the impact of
non linearity on in-flight calibration, which is shown to be negligible.Comment: this paper is part of the Prelaunch status LFI papers published on
JINST: http://www.iop.org/EJ/journal/-page=extra.proc5/jinst; This is an
author-created, un-copyedited version of an article accepted for publication
in JINST. IOP Publishing Ltd is not responsible for any errors or omissions
in this version of the manuscript or any version derived from it. The
definitive publisher authenticated version is available online at
10.1088/1748-0221/4/12/T12011
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