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Digital twin for advanced optimal coordination scheme of distance and Dual-Stage overcurrent relays
No full textIntegrating Distributed Generators (DGs), particularly renewable energy sources such as wind systems, into traditional power network presents significant protection coordination challenges. This study introduces a new optimal coordination scheme for distance and double-Stage Overcurrent (OCR) characteristics relays, utilizing digital twin technology. The proposed dual-stage of OCR protection to enhance the efficacy of the coordination between distance relays and OCRs. By employing advanced digital twin models and Hardware-in-the-Loop (HIL) testing, the proposed scheme aims to enhance fault management and relay coordination for microgrids. The scheme's effectiveness is evaluated using a reference power network (CIGRE radial and mesh network) with and without wind systems under various fault types and locations. The study demonstrates substantial improvements over traditional and modern dynamic distance relays coordination approaches, including a reduction in maximum tripping time from 0.85 s to 0.19 s with the dual-stage scheme. Comparative analysis of digital simulation and physical twin relays further validates the accuracy and robustness of the proposed scheme
Emergence and spread of the SARS-CoV-2 omicron (BA.1) variant across Africa: an observational study.
Get PDFIn mid-November, 2021, the SARS-CoV-2 omicron variant (B.1.1.529; BA.1 sublineage) was detected in southern Africa, prompting international travel restrictions. We aimed to investigate the spread of omicron BA.1 in Africa. In this observational study, samples from patients infected with SARS-CoV-2 from 27 laboratories in 24 African countries, collected between June 1, 2021 and April 14, 2022, were tested for omicron BA.1 and delta (B.1.617.2) variants using real-time RT-PCR. Samples that tested positive for BA.1 by RT-PCR and were collected before estimated BA.1 emergence according to epidemiological properties were excluded from downstream analyses. The diagnostic precision of the assays was evaluated by high-throughput sequencing of samples from four countries. The observed spread of BA.1 was compared with mobility-based mathematical simulations and entries for SARS-CoV-2 in the Global Initiative on Sharing All Influenza Data (GISAID) genomic database. We estimated the effective reproduction number (R ) at the country level considering the BA.1 fraction and the reported numbers of infections. Phylogeographical analyses were done in a Bayesian framework. Through testing of 13 294 samples from patients infected with SARS-CoV-2, we established that, by November-December, 2021, omicron BA.1 had replaced the delta variant of SARS-CoV-2 in all African subregions, following a south-north gradient, with a median R of 2·60 (95% CI 2·46-2·71). This south-north spread, established on the basis of PCR data, was substantiated by phylogeographical reconstructions, ancestral state reconstructions, and GISAID data. PCR-based reconstructions of country-level BA.1 predominance and the availability of BA.1 genomic sequences in GISAID correlated significantly in time (p=0·0002, r=0·78). The first detections of BA.1 in high-income settings beyond Africa were predicted accurately in time by mobility-based mathematical simulations (p<0·0001). Comparing PCR-based reconstructions with mobility-based mathematical simulations suggested that SARS-CoV-2 infections in Africa were under-reported by approximately ten times. Inbound travellers infected with BA.1, departing from five continents, were identified in six African countries by early December, 2021. Omicron BA.1 was widespread in Africa when travel bans were implemented, limiting their effectiveness. Combined with genomic surveillance and mobility-based mathematical modelling, PCR-based strategies can inform R and the geographical spread of emerging pathogens in a cost-effective and timely manner, and can guide evidence-based, non-pharmaceutical interventions such as travel restrictions or physical distancing. Bill & Melinda Gates Foundation. For the French, Portugese and Spanish translations of the abstract see Supplementary Materials section. [Abstract copyright: Copyright © 2025 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.
The colorectal cancer microenvironment: Preclinical progress in identifying targets for cancer therapy.
Get PDFColorectal cancer (CRC) is a common cancer with high mortality rates. Despite progress in treatment, it remains an incurable disease for many patients. In CRC, the tumor microenvironment (TME) plays critical roles in tumor growth, progression, patients' prognosis, and response to treatments. Understanding TME complexities is important for developing effective therapies. In vitro and in vivo preclinical models are critical in understanding the disease, discovering potential targets, and developing effective therapeutics. In this review, we focus on preclinical research studies associated with modulation of the TME in CRC. These models give insights into understanding the role of stroma and immune cell components of the TME in CRC and improve clinical responses, providing insights in novel treatment options. Various studies have focused on targeting the TME in CRC to improve responses to different therapeutic approaches. These include identifying targets for cancer therapies, targeting molecular signaling, and enhancing the efficacy of immunotherapeutic modalities. Furthermore, targeting stromal and angiogenic factors in the TME may provide new therapeutic options. Overall, understanding and targeting the TME in CRC is a promising approach for improving therapeutic outcomes
Integration of Focused Ultrasound and Dynamic Imaging Control System for Targeted Neuro-modulation
Get PDFBackgroundTranscranial Direct Current Stimulation (tDCS) and Transcranial Magnetic Stimulation (tMS) have received widespread clinical use as techniques within a Non-Invasive Brain Stimulation (NIBS) domain, whose primary focus is modulation of neural activity to treat neurological and psychiatric disorders. Despite these advancements, precision targeting of deep brain structures remains a challenge faced with great need of another innovation that will improve precision and reduce the risks. A novel methodology integrating transcranial Focused Ultrasound (tFUS) with real-time functional imaging modalities, including functional Magnetic Resonance Imaging (fMRI) and Near-Infra-Red Spectroscopy (NIRS), is proposed in this study as the Integrated Focused Ultrasound and Real-Time Imaging Control System (IFURTICS).Principle resultsClosed loop algorithms employed by IFURTICS allow it to dynamically vary stimulation parameters in response to real-time feedback on neural activity, allowing for accurate targeting of sensitive networks while minimizing deleterious collateral effects.ConclusionsClinical trials using standard datasets of fMRI and NIRS have proved that the approach improved targeting accuracy by ∼18 %, reduced off-target effects by ∼55 % and enhanced therapeutic outcomes by 50 % over current methods, suggesting its potential as a transformative approach to precision neuro-modulation
Sedation management and processed EEG-based solutions during venovenous extracorporeal membrane oxygenation: a narrative review of key challenges and potential benefits.
Get PDFExtracorporeal membrane oxygenation (ECMO) is an established technique for managing severe cardiorespiratory failure. However, it is invasive and requires profound analgo-sedation during initiation and often throughout the therapy. Managing sedation in venovenous (VV) ECMO patients is particularly challenging due to the impact of ECMO circuits on pharmacokinetics and specific patient requirements. This can lead to unpredictable sedative effects and require multiple drugs at higher doses. Additionally, sedation is usually managed with traditional scoring methods, which are subjective and invalid during neuromuscular blockade. These uncertainties may impact outcomes. Recent clinical practice increasingly focuses on reducing sedation to enable earlier physiotherapy and mobilisation, particularly in patients awaiting transplants or receiving mechanical circulatory support. In this context, processed electroencephalogram-based (pEEG) sedation monitoring might be promising, having shown benefits in general anaesthesia and intensive care. However, the technology has limitations, and its benefits in ECMO practice have yet to be formally evaluated. This review provides insights into the challenges of ECMO sedation, including pharmacokinetics, unique ECMO requirements, and the implications of inadequate sedation scores. Finally, it includes a brief overview of the practicality and limitations of pEEG monitoring during VV-ECMO, highlighting a significant research gap. [Abstract copyright: © 2025. The Author(s).
Advanced Microgrid Protection Utilizing Zero Sequence Components with Hard-ware-in-the-Loop Testing
Get PDFMicrogrid protection and ground fault management are critical aspects of modern power distribution systems, especially with the increasing integration of Distributed Generators (DGs) such as renewable energy sources. Effective protection schemes are essential to ensure the reliability, safety, and resilience of microgrids under various fault conditions. This study addresses a new advancement in microgrid protection and ground fault management. Firstly, the research integrates zero sequence components into the time-inverse characteristics of phase Overcurrent Relays (OCR) and creates a dynamic scheme between two group settings for phase and ground faults. This enhancement improves ground fault detection and provides robust backup for ground OCR, thereby enhancing the overall reliability of microgrid protection schemes. Secondly, the study demonstrates the use of Configurable Function Blocks (CFCs) in digital relays to dynamically adjust relay settings based on zero sequence current detection. This functionality optimizes relay performance under varying fault conditions, addressing mis-coordination issues in low-value ground fault scenarios at traditional OCR scheme and improving fault detection and clearance times. The proposed strategy is extensively validated through Hardware-in-the-Loop (HIL) testing, ensuring its feasibility and effectiveness in real-world scenarios. HIL testing confirms the practical applicability and robustness of the proposed protection scheme, enhancing its reliability. Finally, the study provides a comprehensive framework for the implementation of the proposed protection strategy in real-case protective relays. It includes a detailed methodology and validation process, offering practical guidance for operators to implement and optimize microgrid protection systems
The short- and long-term effects of a fall prevention program on the frequency of falls following total knee replacement: A pragmatic single-blinded randomized controlled trial protocol.
No full textBackground: Falling following total knee replacement (TKR) is a significant issue, and can result in serious fatal and non-fatal injuries. The proposed study aims to investigate the short and long-term effects of integrating a falls prevention program into conventional physiotherapy versus just conventional physiotherapy on the number of falls, and any subsequent effects on balance, and functional ability among TKR patients. Methods and design: This is a parallel group prospective (52 weeks) randomized single-blinded pragmatic controlled trial conducted at Alrazi Orthopedic Hospital, in Kuwait. Sample size will be 90 particpants (45 participants in each group). Particpants will be randomized to intervention or control group. Outcome measures will be collected at baseline, 12 weeks and 52 weeks by investigators who are blinded to treatment allocation. Primary outcome will be fall rate assessed at 52 weeks following the TKR surgery. Secondary outcomes will include knee range of motion, severity of pain, 10-m walk test, Timed Up and Go test, Berg Balance Scale, 30-s sit to stand, patient adherence to home program and patient's satisfaction. Two-way multivariate ANOVA (group × time) will be performed to assess the group (experimental and control group) differences over time (baseline, 12, and 52 weeks). Discussion: Investigating the physiotherapy programs that could minimize or prevent the risk of falling among TKR patients seems important. The proposed study will be the first step toward determining the exercise program that could be effective in reducing the number of falls among TKR patients. ClinicalTrials.gov, Identifier NCT05642260
Robotizing Safety: Prospects and Barriers of Robotic Technology Adoption for Construction Injury Prevention in the UK
Get PDFThe utilization of robots in the construction sector has garnered significant attention in recent years, presenting itself as a transformative technology reshaping traditional construction practices—an industry notorious for its high incidence of injuries and fatalities in the UK. Advancements in robotic and automation systems, coupled with their integration with human workers, are revolutionizing how robots are deployed to address prevalent challenges within the construction landscape. However, despite the potential benefits of robotics, their adoption in the UK remains sluggish. While they hold promise in enhancing safety measures, their efficacy in preventing construction injuries is yet to be fully realized. In light of this context, this research explored both the prospects and barriers associated with robotics adoption within the UK construction industry for injury prevention. Despite the evident need to comprehend and navigate the factors influencing this phenomenon, there is a notable dearth of literature addressing this specific area. The central thesis argues that robotic and automation systems possess the technological capacity to effectively address and mitigate safety risks engendered by construction injuries. However, despite their potential utility, various internal and systemic factors hinder their widespread adoption, thereby constraining their ability to be fully integrated into the industry. This argument is contextualized within the framework of barriers and prospects, with an aim to discern which holds greater prominence and identify existing gaps. A mixed-method approach was employed to investigate this. This involved the collection of primary data through surveys and interviews, with a total of 54 survey respondents and 10 interviewees participating in the study. A consensus emerged among respondents regarding the instrumental role of robotic technology in the UK construction industry, with several barriers identified mirroring findings from existing literature. Analysis unveiled that the UK construction sector currently occupies a transitional phase, oscillating between inertia and a burgeoning inclination towards accelerated adoption, propelled by ongoing efforts towards robotization and automation however adoption remains slow without a clear roadmap for the future of robotics in the UK construction industry Notably, one of the primary findings suggests that robotic adoption is intricately linked to industry perception, although other ancillary factors also influence the utilization of robotics. In light of these findings, several recommendations emerged as best options to improve the robotic adoption in the UK for addressing construction injuries and safety risks including the saliency of ensuring robotic and automation of the UK construction industry must consider the peculiar and evolving needs of the industry and address the human dimensions implicated in its adoption
INTERFACIAL BEHAVIOUR OF 3D PRINTED CONCRETE: FRESH AND HARDENED STAGE
No full textThe construction industry faces significant challenges in meeting the demands of a growing population and urbanisation, which are compounded by environmental sustainability concerns and low productivity. The 3D Printing Concrete (3DPC) technology can address these challenges by overcoming issues related to skilled labour, resource depletion, site safety, and environmental impact, which are prevalent in conventional construction techniques. This innovation offers enhanced geometric freedom and functionality at minimal additional cost, eliminating the need for formwork, and reducing labour through additive manufacturing.However, the acceptance of the 3D Printing Concrete (3DPC) introduces complexities, especially with regard to the stability of fresh concrete during the printing process and the proper stacking of printed layers to avoid failure in its hardened material state. The purpose of the study is to address these challenges by focusing on material formulation, the optimisation of the printing process, and computational analysis.To expand the understanding, the investigation focused on 3D extrusion-based concrete printing of unreinforced and basalt fibre-reinforced concrete. Two critical failure mechanisms in fresh-state concrete, such as elastic buckling and plastic collapse, are identified and evaluated using numerical Finite Element Models (FEM). The FEM models incorporate transient material properties obtained from early-age concrete experimental testing, revealing thixotropic effects and changes in failure behaviour as the concrete ages.In addition, the study emphasises the importance of the triaxial compression test in defining input parameters in numerical modelling. The study demonstrates the effectiveness of numerical models in controlling fresh concrete structural behaviour and facilitating the optimisation of improved geometrical structures. In hardened concrete, the bond strength between layers is recognised as a critical factor influencing the structural behaviour of 3D printed elements. An extensive experimental package is conducted to explore the impact of various process parameters on the bonding strength of 3D printed concrete.The integration of experimental and numerical models enhances the understanding of 3D-printed concrete, particularly its hydration during early hardening and its mechanical strength once hardened. This advancement supports the wider adoption of 3D-printed concrete as a standard practice in construction
Exploring the Lived Experiences of Postgraduate Research Students: A Longitudinal Study
Get PDF0.1 ABSTRACTResearch on student mental health has historically focused on undergraduates with a relative dearth of research on Postgraduate Research (PGR) students (Vitae, 2018). The study sought to redress this imbalance and heeds the call of Advance HE’s PGR Experience Survey (PRES) to investigate engagement and well-being amongst PGR students, alongside indications that they experience higher stress levels (Advance HE, 2019; Williams, 2019). Based on these precepts, this PhD research sought to tap into the lived experiences of PGR students via a longitudinal interview-based Interpretive Phenomenological Analysis (IPA) study. 19 full-time PGRs from University of Manchester (UoM) (n=9) and the University of Salford (UoS) (n=10) across their 1st to 4th (writing-up) year were interviewed in three separate phases over a three-year period. The sample included home, international, and EU students (now having Indefinite Leave to Remain (ILR) status). Four master themes were identified as common across the three phases. They were shared between the universities: Resources and coping strategies to manage the PhD, Challenges from COVID, Pivotal role of PhD supervisor and Poor mental health, Emotional/Overwhelmed and exhausted/ immense stress of the PhD. There is also a range of master themes that are more phase or university-specific.Recommendations arising from the lived experiences of the study’s PGR students include the perception that treating PGR students more like staff may bring benefits. There is also a perceived need to improve university support systems and mental health support training for students and to provide dedicated PGR social spaces, specialised PGR counselling services, increased social events, less frequent attendance monitoring for international students, standardised supervisor relationship training and improved university administration and systems.There are also implications for research and theory on occupational stress and wellbeing, how the PGR students' experience of stress in this study can be elucidated through an understanding of Conservation of Resources (Westman et al, 2004) or in the context of Transactional Models of Stress (Cox & Griffiths, 2010)
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