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An adaptive resolution scheme for performance enhancement of a web-based multi-user VR application
No full textOver the last few years, several frameworks have been introduced to help developers build virtual reality (VR) experiences for the web. One such open-source web framework is the A-Frame framework, which is built on top of WebXR and Three.js. A-Frame can be used to create 3D scenes that can be rendered using compatible browsers such as Chrome and Firefox. The performance of web-based VR applications, however, can be affected due to the limitations of the CPU and GPU, especially in multi-user applications. In this paper, an A-Frame-based multi- user VR application is developed and the performance is analyzed under different scenarios, demonstrating how an increase in the number of users affects metrics related to VR quality of experience (QoE). Then, an Adaptive Resolution Scheme for VR (ARS-VR) is proposed, which improves the VR performance in terms of frame rate and frame latency on remote devices with limited processing and display features
Closing the circularity gap via engineering education for circularity with a whole systems and biomimetic perspective
No full textAs reported at the World Economic Forum in Davos, Switzerland in January of 2019 only 9% of the world is circular (defined as the annual percentage of materials that are returned to the system vs. discarded as waste). It is estimated that the 91% that is not circular contributes to over 60% of global greenhouse gas (GHG) emissions along with an estimated 8 million tons of waste entering our oceans each year. Villanova’s focus on circularity in engineering education includes three graduate level courses: Sustainable Materials and Design, Biomimicry (defined as engineering solutions inspired by nature), and Sustainable Supply Chain, along with industry and grant sponsored class projects, MS and PhD level research. Four key fundamental learning themes emphasized include a whole systems STEEP (social, technical, environmental, economic and political) perspective; assurance that the performance and cost benefits of the incumbent linear solutions are understood, quantified, and rivalled in the circular solution; engaging the right subject matter experts, cross disciplines and stake holders; and ensuring that the right metrics are in place for the final recommended more circular systems. Specific examples in this paper will include highlight projects from the above mentioned courses, circularity focused industry-sponsored class projects, Master’s level research developing a closed loop system for converting food waste to a hydrochar material that re-enters the system for energy and other higher value uses, and PhD research on renewably sourced polymers for aircraft composites. The challenges we face to move towards the circular economy from our current linear economy are daunting. We believe, however, that through the described collaborative engineering educational learning experiences for today’s future leaders we will be able to make a significant impact
In silico interactions of statins with cell death-inducing DNA fragmentation factor-like effector A (CIDEA)
No full textStatins are the low-density lipoproteins (LDL)-cholesterol-lowering drugs of first choice and are used to prevent
the increased risk of cardiovascular and cerebrovascular diseases. Although some of their effects are well known,
little is known about their ability to regulate other lipid-related proteins which control apoptotic mechanisms.
The aim of this study was to explore whether statins can bind to cell death-inducing DNA fragmentation factor like effector A (CIDEA), which might be a possible pleiotropic mechanism of action of these drugs on the
modulation of apoptosis and lipid metabolism. The structures of statins were subjected to molecular docking and
dynamics with the human CIDEA protein to investigate the interaction pattern and identify which residues are
important. The docking results indicated that atorvastatin and rosuvastatin showed the best interaction energy
(− 8.51 and − 8.04 kcal/mol, respectively) followed by fluvastatin (− 7.39), pitavastatin (− 6.5), lovastatin
(− 6.23), pravastatin (− 6.04) and simvastatin (− 5.29). Atorvastatin and rosuvastatin were further subjected to
molecular dynamics at 50 ns with CIDEA and the results suggested that rosuvastatin-CIDEA complex had lower
root-mean square deviation and root-mean square fluctuation when compared with atorvastatin-CIDEA. Since
two arginine residues -ARG19 and ARG22-were identified to be common for the interaction with CIDEA, a single point mutation was induced in these residues to determine whether they are important for binding interaction.
Mutation of these two residues seemed to affect mostly the interaction of atorvastatin with CIDEA, suggesting
that they are important for the binding and therefore indicate another possible metabolic mechanism of the
pleiotropic effects of this statin
Design and development of a hydrogel formulation with nanoparticles for the treatment of glioblastoma multiforme
No full textGlioblastoma multiforme (GBM) is the most aggressive form of brain tumours. GBM treatment is challenging because tumours are highly invasive and it is difficult to achieve effective therapeutic doses of drugs into the brain. Indeed, the Blood Brain Barrier (BBB) impairs most of the anti-cancer drugs to reach the tumour site. To overcome this problem, different drug delivery methods, such as the direct delivery of drugs into the brain after tumour removal surgery, have been proposed. Biomaterials are in the front line of the research focus for new treatment options. Especially, biocompatible polymers have been proposed in hydrogel-based formulations aiming at injectable and localized therapies. These formulations can comprise chemotherapeutic drugs, nanoparticles, cells, nucleic acids, and diagnostic agents. In this thesis, a hydrogel-based formulation containing free drug and drug-loaded stimuli-responsive nanoparticles was developed and tested for the treatment of GBM. Specifically, in Chapter 2 a detailed description of the materials and methods used in this work is presented. In Chapter 3, the first specific objective was the synthesis and characterization of the stimuli-responsive mesoporous silica nanoparticle capped with polyethylene glycol (MSN-PEG). This was followed by the evaluation of two loaded chemotherapeutic drugs, temozolomide (TMZ) and paclitaxel (PTX) concerning the loading capacity, release profile and in vitro effect on U-87 GBM cells and healthy neurons. In addition, the stability of the nanoparticles was analysed to support the interpretation of all these data. In Chapter 4, three gels (two thermoresponsive and one chemically crosslinked) were evaluated for the combination with the nanoparticle with or without the stimuli-responsive modification. The release profile of these nanoparticles and free drugs (temozolomide, paclitaxel and carmustine) from the gels was thoroughly analysed to increase the understanding on the behaviour of the combination as a drug delivery system. This shed light on the promising materials to be used as the delivery platform for the nanoparticles developed on Chapter 3. Moreover, gel degradation was also evaluated. Through a step by step screening process, the crosslinked (CX) hydrogel was selected to compose the final formulation (GlioGel) together with free TMZ and PTX-loaded nanoparticles. In Chapter 5, the efficacy of the combination therapy was evaluated in a 3D in vitro model and the final formulation was implanted in vivo in an animal model of GBM. We used tumour spheroids as a 3D platform to evaluate the effect of the formulation in vitro regarding cytotoxicity and nanoparticles penetration. In addition, the formulation combining free TMZ and PTX-loaded MSN-PEG into the CX hydrogel was implanted in U-87 tumour-bearing mice after resection surgery to evaluate treatment efficacy in vivo. Finally, Chapter 6 is a general discussion of the research developed in this project, including the main findings of each part of the work and future research that can be conducted based on these project findings. In conclusion, a hydrogel-based formulation loaded with free chemotherapeutics and loaded nanoparticles was developed. In vivo results showed efficacy against GBM tumours after surgical resection in mice. Therefore, the GlioGel formulation is a viable option to treat GBM and improve the current chemotherapy outcomes in those patients
Feed Restriction Reveals Distinct Serum Metabolome Profiles in Chickens Divergent in Feed Efficiency Traits
No full textRestrictive feeding influences systemic metabolism of nutrients; however, this impact
has not been evaluated in chickens of diverging feed efficiency. This study investigated the effect
of ad libitum versus restrictive feeding (85% of ad libitum) on the serum metabolome and white
blood cell composition in chickens of diverging residual feed intake (RFI; metric for feed efficiency).
Blood samples were collected between days 33 and 37 post-hatch. While serum glucose was
similar, serum uric acid and cholesterol were indicative of the nutritional status and chicken’s
RFI, respectively. Feed restriction and RFI rank caused distinct serum metabolome profiles, whereby
restrictive feeding also increased the blood lymphocyte proportion. Most importantly, 10 amino
acids were associated with RFI rank in birds, whereas restrictive feeding affected almost all detected
lysophosphatidylcholines, with 3 being higher and 6 being lower in restrictively compared to ad
libitum fed chickens. As indicated by relevance networking, isoleucine, lysine, valine, histidine, and
ornithine were the most discriminant for high RFI, whereas 3 biogenic amines (carnosine, putrescine,
and spermidine) and 3 diacyl-glycerophospholipids (38:4, 38:5, and 40:5) positively correlated with
feed intake and body weight gain, respectively. Only for taurine, feed intake mostly explained
the RFI-associated variation, whereas for most metabolites, other host physiological factors played
a greater role for the RFI-associated differences, and was potentially related to insulin-signaling,
phospholipase A2, and arachidonic acid metabolism. Alterations in the hepatic synthesis of long-chain
fatty acids and the need for precursors for gluconeogenesis due to varying energy demand may
explain the marked differences in serum metabolite profiles in ad libitum and restrictively fed birds
‘I hated being ghosted’ – The relevance of social participation for living well with post-stroke aphasia: Qualitative interviews with working aged adults
No full textBackground
In the context of increasing incidence of stroke in working aged adults, there is a specific need to explore the views of working aged adults with post-stroke aphasia, whose communication difficulties may result in restricted social participation, loss of employment and changed relationship and parenting roles. This study aimed to explore the perspectives of working aged adults with post-stroke aphasia in relation to social participation and living well with aphasia (LWA).
Design and participants
We conducted qualitative interviews with 14 people with post-stroke aphasia (PWA). Data were analysed following principles of reflexive, thematic analysis.
Patient or Public Contribution: A Public and Patient Involvement aphasia advisory group inputted into the study design and interpretation of data.
Results
Social participation spanned 5 themes: Relationships and roles; Social support; Peer network, Aphasia awareness; and Employment and training. Meaningful, interesting social participation for LWA is individually defined. Working aged PWA may require flexible support with parenting, accessing a diverse social network and finding opportunities for meaningful social connection, training and employment.
Conclusions
The findings extend knowledge of social participation in the context of LWA for working aged adults by elucidating the individually defined nature of meaningful participation and how PWA may need flexible support with parenting, accessing a diverse social network and training and employment. For aphasia research, policy and services to be relevant, it is crucial that working aged PWA are meaningfully involved in setting the aphasia agenda
Mixture of Experts Approach for Behavioral Modeling of RF Power Amplifiers
No full textThe 2021 IEEE Topical Conference on RF/Microwave Power Amplifiers for Radio and Wireless Applications (PAWR 2021), Virtual Conference, 17-20 January 2021Piece-wise (PW) behavioral models are commonly adopted when modeling RF power amplifiers (PAs) that exhibit strong amplitude dependent nonlinear distortion characteristics. In this paper, we consider a new PW model for PAs based on the mixture of experts (ME) approach. We first introduce the ME framework theory while also extend it such that it can be applied to model complex baseband signals and nonlinearities. Then, we show how the ME model allows overcoming some of the intrinsic shortcomings that existing PW behavioral models commonly exhibit, which translates into improved modeling accuracy. The proposed solution is validated with extensive RF measurements on a load modulated balanced PA at 2.1 GHz, excited by a 320 MHz OFDM signal, and is benchmarked against several state-of-the art PW models
Tracking the Evolution of Communities in Dynamic Social Networks
No full textReal-world social networks from many domains can naturally be modelled as dynamic graphs. However, approaches for detecting communities have largely focused on identifying communities in static graphs. Therefore, researchers have begun to consider the problem of tracking the evolution of groups of users in dynamic scenarios. Here we describe a model for tracking communities which persist over time in dynamic networks, where each community is characterised by a series of evolutionary events. Based on this model, we propose a scalable community-tracking strategy for efficiently identifying dynamic communities. Evaluations on a large number of synthetic graphs containing embedded evolutionary events demonstrate that this strategy can successfully track communities over time in dynamic networks with different levels of volatility. We then describe experiments to explore the evolving community structures present in real mobile operator networks, represented by monthly call graphs for millions of subscribers.Science Foundation Irelan
Regulatory focus and perceptions of ageing: exploring the connections
No full textObjectives:Perceptions of ageing can become a self-fulfilling prophecy for older adults, with those who hold more negative views of ageing experiencing more negative consequences of the ageing process, including poorer health and cognitive declines. Exposure to negative stereotypes about their group can also affect older adults performance in cognitive tests, as they are more likely to adopt a prevention focus to avoid mistakes, therefore, performing poorly in tasks requiring them to adopt a gains-oriented focus. Based on regulatory focus theory, we hypothesised that negative perceptions of ageing and stereotype threat may be connected, specifically we hypothesised that those with more negative perceptions of ageing would also have a stronger trait prevention focus.Method: Two hundred adults aged 60+ took part in an online questionnaire examining their perceptions of ageing and their trait regulatory focus.Results and Conclusion: Results indicated that negative perceptions of ageing were predictive of a stronger trait prevention focus in a hierarchical multiple regression model. This provides evidence that older adults with more negative perceptions of ageing may adopt a stronger prevention focus, potentially influencing psychological attitudes to everyday tasks and behaviours. Perceptions of ageing and regulatory focus can have implications for the efficacy of health messaging for older adults
Burden of chronic kidney disease and rapid decline in renal function among adults attending a hospital-based diabetes center in Northern Europe
No full textIntroduction This study aimed to determine the prevalence of diabetic kidney disease (DKD) and rapid renal function decline and to identify indices associated with this decline among adults attending a diabetes center in Northern Europe.
Research design and methods This is a retrospective cohort study of 4606 patients who attended a diabetes center in Ireland between June 2012 and December 2016. Definition/staging of chronic kidney disease used the Kidney Disease: Improving Global Outcomes (KDIGO) 2012 classification based on data from the most recently attended appointment. Relevant longitudinal trends and variabilities were derived from serial records prior to index visit. Rapid renal function decline was defined based on per cent and absolute rates of estimated glomerular filtration rate (eGFR) change. Multiple linear regression was used to explore the relationships between explanatory variables and per cent eGFR change.
Results 42.0% (total), 23.4% (type 1 diabetes), 47.9% (type 2 diabetes) and 32.6% (other diabetes) had DKD. Rapid decline based on per cent change was more frequent in type 2 than in type 1 diabetes (32.8% vs 14.0%, p<0.001). Indices independently associated with rapid eGFR decline included older age, greater number of antihypertensives, higher log-normalized urine albumin to creatinine ratio (LNuACR), serum alkaline phosphatase, thyroid stimulating hormone, variability in systolic blood pressure and variability in LNuACR, lower glycated hemoglobin, high-density lipoprotein cholesterol and diastolic blood pressure, and lack of ACE inhibitor/angiotensin receptor blocker prescription.
Conclusions DKD (using the KDIGO 2012 classification) and rapid eGFR decline were highly prevalent among adults attending a hospital-based diabetes clinic in a predominantly Caucasian Northern European country. The burden was greater for adults with type 2 diabetes. Expected as well as potentially novel clinical predictors were identified.TPG is supported by a Hardiman Scholarship from the College of Medicine, Nursing and Health Science, National University of Ireland Galway and a bursary from the Irish Endocrine Society/Royal College of Physicians of Ireland. The authors are supported by grants from the European Commission [Horizon 2020 Collaborative Health Project NEPHSTROM (grant number 634086; TPG, MNI, MDG), Science Foundation Ireland [REMEDI Strategic Research Cluster (grant number 09/SRC-B1794; MDG), CÚRAM Research Centre (grant number 13/RC/2073_P2; MDG)], HRB, Ireland Grant (grant number: EIA 2017-017) and the European Regional Development Fund.
The materials presented and views expressed are the responsibility of the author(s) only. The EU Commission takes no responsibility for any use made of the information set out