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Real-valued discrete-time impulse response representation of bandpass S-parameters
No full textThe 2016 46th European Microwave Conference (EuMC), London, United Kingdom, 4-6 October 2016Accurate and efficient time-domain simulation techniques for broadband microwave networks at system level are highly desirable in modern computer-aided-design (CAD) tools, because of advantages in terms of high simulation speed and the reduced requirement for full circuit-level details of the simulated networks. A method for accurate time-domain representation of bandpass S-parameters is proposed in this paper, in order to produce fast time-domain steady-state responses of broadband high-frequency linear, time-invariant systems. A real-valued discrete-time impulse response (DTIR) representation is used in the proposed method. As a result, the processes of down-conversion and up-conversion of input signals and system bandpass transfer functions normally required in bandpass analysis, can be effectively avoided. For example, the method can be used in the design of distortion cancellation circuits in full-duplex communication systems.Science Foundation IrelandChina Scholarship Counci
Modelling the sensing radius of a coaxial probe for dielectric characterisation of biological tissues
No full textThe open-ended coaxial probe is the most common measurement tool used to dielectrically characterize biological tissues. Most healthy and malignant biological tissues are macroscopically heterogeneous, with the exception of a few tissues, such as liver. Heterogeneous biological samples are dielectrically characterized by defining the dielectric properties of each tissue type constituting the sample. In order to accurately characterize a specific tissue type with a coaxial probe, it is fundamental that only the tissue of interest is contained within the probe sensing volume, which is defined by the sensing radius and sensing depth. In the literature, several studies have investigated the sensing depth with bilayer or multilayer heterogeneous tissues. However, in this paper, we examine the sensing radius through concentrically heterogeneous tissues. In particular, samples composed of two different concentric tissues were modeled to estimate the minimum width of the homogenous tissue region required to accurately acquire the corresponding dielectric properties. As recent studies have indicated that the sensing radius depends on the dielectric properties of the interrogated tissue, in this paper, the sensing radius of a coaxial probe has been numerically quantified across a wide range of scenarios, involving different tissues with varying dielectric contrasts. The numerical results indicate that: 1) the sensing radius increases with the contrast in permittivity between the constituent tissues and 2) the sensing radius is highly dependent on the permittivity of the tissue closest to the inner conductor of the probe. Finally, the numerical outcome has been confirmed with dielectric measurements performed on animal tissues.This work has been developed in the framework of COST Action MiMed (TD1301)
Sexual health questions included in the Health Behaviour in School-aged Children (HBSC) Study: an international methodological pilot investigation
No full textBackground
This paper describes the methodological developments of the sexual health items included in the Health Behaviour in School-aged Children (HBSC) study since their mandatory inclusion in the study in 2002. The current methodological, ethical and pedagogical challenges in measuring young people’s sexual health behaviours are discussed along with the issues associated with the sexual health items introduced to the HBSC study in 2002. The development and piloting of new cross-national items for use in the 2013/14 HBSC data collection are presented and discussed.
Methods
An international pilot study was undertaken to determine the impact of these proposed changes. Questionnaires and classroom discussion groups were conducted in five pilot countries in 2012/2013 (France, Hungary, Ireland, Portugal and Romania) with a total of 612 school-aged children (age M = 15.55 years, SD = 0.95).
Results
The majority of participants in each country provided positive feedback about the appropriateness of the questions. Some small cross-national differences were found in the self-reported quantitative data relating to the appropriateness of the questions (χ2 = 22.831, df = 9, p = .007, V = .117). Qualitative feedback suggests that for the vast majority of students the phrasing and age-targeting of the questions were considered appropriate. With the exception of a small number of respondents who commented on the clarity and/or personal nature of the content, no specific issues with the questions were identified.
Conclusions
These findings provide guidance on the answerability (including the extent of missing and inconsistent data), understandability, acceptability (including in different cultures) and relevance of questions to potential participants. The findings from the pilot study suggest that in general, the questions are understandable, acceptable, and of a high priority to the target population, and that the simplification has significantly reduced the proportion of missing data. The new developments thus enhance the capacity of the questions to measure cross-nationally, sensitive aspects of young people’s sexual behaviour. These questions were included in the 2013/2014 round of the HBSC survey and will continue to be used to monitor trends in adolescent sexual health and behaviours, and to inform and influence health services and health education policy and practice at local, national and international levels.The authors thank all the schools and young people who participated in the pilot study and who have participated in past HBSC studies. They would also like to thank the following colleagues for their help with the pilot study: Ágnes Németh (Principal Investigator) and Emese Zsiros from Hungary, The HBSC Ireland Team, the Addiction Switzerland Team, Adriana Baban (Principal Investigator, Romania), Margarida Gaspar de Matos (Principal Investigator) and Lúcia Ramiro from Portugal. HBSC is an international study carried out in collaboration with WHO/EURO. The International Coordinator of the 2013/2014 survey was Professor Candace Currie, PhD (University of St. Andrews, School of Medicine, Child and Adolescent Health Research Unit, Scotland) and the Data Bank Manager was Professor Oddrun Samdal, PhD (University of Bergen, HBSC Data Management Centre, Norway). For details of the HBSC study, see http://www.hbsc.org. The authors would also like to thank all past and current members of the HBSC Sexual Health Focus Group. Finally, they thank the valuable comments of the reviewers on the first version of the manuscript
Experimental and computational characterization of the effect of manufacturing-induced defects on high temperature, low-cycle fatigue for MarBN
No full textManufacturing-induced defects are a key source of crack initiation and component failure under high temperature cyclic loading. In this work, 3D X-ray micro-computed tomography and microstructural analysis of manufacturing-induced defects is presented for forged and cast MarBN martensitic-ferritic steel, along with high temperature, low cycle fatigue testing, for assessment of the comparative effects of two manufacturing processes. Forging is found to significantly reduce the volume fraction and complexity of manufacturing defects, compared to the cast material, resulting in approximately double the fatigue life. A voxel-based finite element methodology for experimentally-identified cast and forged manufacturing defects is presented, in conjunction with a multiaxial, critical-plane damage model, within a unified viscoplastic user-material subroutine. The effect of the complex morphologies of the manufacturing defects on high temperature fatigue crack initiation is thus quantified, highlighting the relative effects of the two different manufacturing processes.The authors gratefully acknowledge funding from the Irish Research Council and GE Power under the Enterprise Partnership Scheme (EPSPG/2015/55), and the SFI Research Centre for Advanced Manufacturing, I-Form (SFI/16/RC/3872). The authors would like to express their gratitude to those in the IMPEL consortium. The authors acknowledge the facilities and technical assistance of the Centre for Microscopy & Imaging at the National University of Ireland Galway. The authors wish to acknowledge the DJEI/DES/SFI/HEA Irish Centre for High-End Computing (ICHEC) for the provision of computational facilities and support.2021-05-2
Numerical study of a Whitham equation exhibiting both breaking waves and continuous solutions
No full textWe consider a Whitham equation as an alternative for the Korteweg–de Vries (KdV) equation in which the third derivative is replaced by the integral of a kernel, i.e., ηxxx in the KdV equation is replaced by ∫∞−∞Kν(x−ξ)ηξ(ξ,t)dξ. The kernel Kν(x) satisfies the conditions limν→∞Kν(x) = δ″(x), where δ(x) is the Dirac delta function and limν→0Kν(x) = 0. The questions studied here, by means of numerical examples, are whether adjustment of the parameter ν produces both continuous solutions and shocks of the kernel equation and how well they represent KdV solutions and solutions of the underlying hyperbolic system. A typical example is for resonant forced oscillations in a closed shallow water tank governed by the kernel equation, which are compared with those governed by a partial differential equation. The continuous solutions of the kernel equation associated with frequency dispersion in the KdV equations limit to the shocks of the shallow water equations as ν → 0. Two experimental problems are solved in a single equation. As another example, suitable adjustment of ν in the kernel equation produces solutions reminiscent of a hydraulic and undular bore
Synthesizing game audio using deep neural networks
No full textHigh quality audio plays an important role in gaming, contributing to player immersion during gameplay. Creating audio content which matches overall theme and aesthetic is essential, such that players can become fully engrossed in a game environment. Sound effects must also fit well with visual elements of a game so as not to break player immersion. Producing suitable, unique sound effects requires the use of a wide range of audio processing techniques. In this paper, we examine a method of generating in-game audio using Generative Adversarial Networks, and compare this to traditional methods of synthesizing and augmenting audio.This research is funded under the SFI Strategic Partnership Program by Science Foundation Ireland (SFI) and FotoNation Ltd. Project ID: 13/SPP/I2868
on Next Generation Imaging for Smartphone and Embedded Platforms. This
work is also supported Irish Research Council Employment Based Programme
Awards EBP/2017/476 and EBPPG/2016/28
The NR4A agonist, cytosporone B, attenuates pro-inflammatory mediators in human colorectal cancer tissue ex vivo
No full textInflammation is a pivotal pathological factor in colorectal cancer (CRC) initiation and progression, and modulating this inflammatory state has the potential to ameliorate disease progression. NR4A receptors have emerged as key regulators of inflammatory pathways that are important in CRC. Here, we have examined the effect of NR4A agonist, Cytosporone B (CsnB), on colorectal tissue integrity and its effect on the inflammatory profile in CRC tissue ex vivo. Here, we demonstrate concentrations up 100 mM CsnB did
not adversely affect tissue integrity as measured using transepithelial electrical resistance, histology and crypt height. Subsequently, we reveal through the use of acytokine/chemokine array, ELISA and qRT-PCR analysis that multiple pro-inflammatory mediators were significantly increased in CRC tissue compared to control tissue, which were then attenuated with the addition of CsnB (such as IL-1b, IL-8 and TNFa). Lastly, stratification of the data revealed that CsnB especially alters the inflammatory profile of tumours derived from males who had not undergone chemoradiotherapy. Thus, this study demonstrates that NR4A agonist CsnB does not adversely affect colon tissue structure or functionality and can attenuate the pro-inflammatory state of human CRC tissue ex viv
OSiD: opening the conceptual design of biobased processes to a context-sensitive sustainability analysis
No full textBiobased production has been promoted as an alternative to fossil-based production to mitigate climate change. However, emerging concerns over the sustainability of biobased products have shown that tensions can emerge between different objectives and concerns, like emission reduction targets and food security, and that these are dependent on local contexts. Here we present the Open Sustainabilityin-Design (OSiD) framework, the aim of which is to integrate a context-sensitive sustainability analysis in the conceptual design of biobased processes. The framework is illustrated, taking as an example the production of sustainable aviation fuel in southeast Brazil. The OSiD framework is a novel concept that brings the perspectives of stakeholders and considerations of the regional context to an ex ante sustainability analysis of biobased production. This work also illustrates a way to integrate methods from different scientific disciplines supporting the analysis of sustainability and the identification of tensions
between different sustainability aspects. Making these tensions explicit early in the development of biobased production can make them more responsive to emerging sustainability concerns. Considering the global pressure to reduce carbon emissions, situating sustainability analyses in their socio-technical contexts as presented here can help to explain and improve the impacts of biobased production in the transition away from fossil resources
Red clover: A promising pasture legume for Ireland
No full textRed clover is considered a very productive but short
lived perennial legume. Previous research has shown
attractive yields for red clover in the first year after
establishment (O’Kiely et al., 2006). This experiment
quantified the impacts of cultivar, companion grass,
harvest schedule and nitrogen fertiliser on crop yield in
the sixth year after establishment, and compared these
to grass receiving inorganic N fertiliser
Psychometric assessment of EQ-5D-5L and ReQoL measures in patients with anxiety and depression: construct validity and responsiveness
No full textPurpose: Generic health measures have been questioned for quantifying mental-health-related outcomes. In patients with anxiety and/or depression, our aim is to assess the psychometric properties of the preference-based EQ-5D-5L (generic health) and ReQoL-UI (recovery-focussed quality of life) for economic evaluation against the PHQ-9 (depression) and GAD-7 (anxiety). EQ-5D-5L anxiety/depression item and ReQoL-10 are also assessed.
Methods: A 2:1 (intervention: control) randomised controlled trial collected measures at baseline and 8 weeks post baseline; in the intervention arm, data were also collected 3, 6, 9, and 12-months post baseline. EQ-5D-5L preference-based scores were obtained from the value set for England (VSE) and \u27cross-walked\u27 EQ-5D-3L United Kingdom (UK) value set scores. ReQoL-UI preference-based scores were obtained from its UK value set as applied to seven ReQoL-10 items. EQ-5D-5L and ReQoL measures\u27 construct validity and responsiveness were assessed compared against PHQ-9 and GAD-7 scores and group cut-offs.
Results: 361 people were randomised to intervention (241) or control (120). ReQoL-UI/-10 had better construct validity with depression severity than the EQ-5D-5L (VSE/cross-walk scores), which had relatively better construct validity with anxiety severity than the ReQoL-UI/-10. Across all intervention-arm time-points relative to baseline, responsiveness was generally better for EQ-5D-5L (VSE in particular) than ReQoL-UI, but worse than ReQoL-10.
Conclusion: There is insufficient evidence to recommend the ReQoL-UI over EQ-5D-5L for economic evaluations to capture anxiety severity. However, there may be rationale for recommending the ReQoL-UI over the EQ-5D-5L to capture depression severity given its better construct validity, albeit poorer responsiveness, and if recovery-focussed quality of life relative to condition-specific symptomology is the construct of interest