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Groundwater level predictions in the Thames Basin, London over extended horizons using Transformers and advanced machine learning models
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Data will be made available on request.This study breaks new ground by using the Temporal Fusion Transformer (TFT) method for groundwater level prediction, addressing the complex dynamics of the Thames Basin aquifer in England. Our research combines extensive hydrological data collected from the Thames Basin with advanced machine learning, where a complex network of rivers and streams substantially affects groundwater dynamics. Unlike previous studies, this research focuses on long-term forecasting with deep learning, offering, for the first time, a 60-day prediction horizon based on daily data. To rigorously examine the model performance and robustness on new, unseen data, we applied the walk-forward validation method and other matrices such as RMSE and R2 coupled with the Holdout technique. The models used were Long Short-Term Memory (LSTM), Attention-based LSTM, LSTM with Bayesian optimisation, Attention-based LSTM with Bayesian optimisation and TFT. They were used on the basin's Chalk, Jurassic Limestone, and Lower greensand aquifers. Whilst both LSTM models were optimised using the Bayesian technique, TFT was applied for its inherent capability in complex time series. Our methodology processed historical groundwater and rainfall data from 2001 to 2023, accounting for the potential lag in aquifer response to the proximity of the river system. The dataset served as training, validation, and holdout for each model, focusing on capturing the dynamic temporal fluctuation. The results clearly showed the superiority of the TFT model in all aquifer types compared to other models across all horizons. The Limestone had the greatest result in the 7-day projections, with an RMSE of 0.02 and R2 of 0.98; Whilst the Chalk and Lower greensand, had RMSEs of 0.03 with R2 values of 0.75 and 0.95, respectively. The Limestone aquifer performed best for the 30-day horizon again (RMSE=0.06, R2=0.85), with the Chalk and Lower greensand aquifer yielding RMSE of 0.04 and 0.12 and R2 values of 0.64 and 0.74, respectively. In the 60 days predictions, the best results were observed in the limestone aquifer with RMSE of 0.09 and R2 of 0.65 in holdout validation. However, in chalk and lower greensand aquifers, the TFT showed RMSEs of 0.05 and 0.15 and R2s of 0.45 and 0.58, respectively. Traditional LSTM models demonstrated limited predictive power compared to the main model TFT, while the attention mechanism slightly improved the accuracy. This study not only sets a new benchmark in hydrological modelling accuracy but also highlights the potential of advanced machine learning in managing complex aquifers and predicting the water table.The study was partially funded by UKRI project 10063665
A survey on zeroing neural dynamics: models, theories, and applications
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The data that support the findings of this study are available on request from the corresponding author, L. X., upon reasonable request.Extensive research has been conducted in dynamic mathematical problems and real-time industrial control applications, leading to the emergence of zeroing neural dynamics (ZND) as a significant approach. This approach is guided by the fluctuating tendency of state errors, and a link is established between the stability of the zero solution in the neurodynamic system and the convergence of neuron states in a zeroing neural network. Over the last two decades, considerable efforts have been made by numerous scholars to advance the development of ZND, resulting in the formation of a series of ZND models for various mathematical issues and real-world applications. In this paper, the advances in ZND are synthesised from three aspects: models, theories, and applications. Specifically, ZND models are categorised into two main frameworks based on their structures and further classified into different types depending on the dynamics of the specific models under each framework. The two main frameworks identified are the foundational ZND framework and the integral ZND framework. The former serves as the basic structure for exponential type ZND, finite-time type ZND, fixed-time type ZND, and predefined-time type ZND, while the latter is extended with the single-integral type ZND and the double-integral type ZND. Furthermore, the primary analytical methods for the dynamics of each type of ZND are summarised, and the current applications of ZND, including robot manipulator control, multi-agent consistency, dynamic positioning, chaos synchronisation, and image processing, are introduced. Through this survey, a comprehensive understanding of the development history of ZND research, the current research focuses and challenges in ZND models, theories, and applications, as well as future directions and key breakthroughs in ZND research, will be provided to readers.This work was supported in part by the Natural Science Foundation of Hunan Province of China under Grants 2022RC1103, 2021JJ20005, and 2024JJ6320, in part by the National Natural Science Foundation of China under Grants 61866013 and 62406109, and in part by the Hunan Provincial Student Innovation Training Programme under Grant S202410542066
Pinning Synchronization for Stochastic Complex Networks with Randomly Occurring Nonlinearities: Tackling Bit Rate Constraints and Allocations
Get PDFIn this article, the ultimately bounded synchronization problem is investigated for a class of discrete-time stochastic complex networks under the pinning control strategy. Communication between system nodes and the remote controller is facilitated via wireless networks subject to bit rate constraints. The system model is distinguished by the inclusion of randomly occurring nonlinearities. A coding-decoding transmission mechanism under constrained bit rates is introduced to characterize the digital transmission process. To achieve synchronization of the network nodes with the unforced target node, a pinning controller is specifically devised based on the information from partially selected nodes. Through the application of the stochastic analysis method, a sufficient condition is derived for ensuring the mean-square boundedness of the synchronization error system. In addition, an optimization algorithm is introduced to address bit rate allocation and the design of desired controller gains. Within the presented theoretical framework, the correlation between the mean-square synchronization performance and bit rate allocation is further elucidated. To conclude, a simulation example is provided to substantiate the efficacy of the recommended pinning control approach.10.13039/501100019091-Key Area Research and Development Program of Guangdong Province of China (Grant Number: 2021B0101410005);
10.13039/501100003453-Natural Science Foundation of Guangdong Province of China (Grant Number: 2021A1515011634 and 2021B1515420008);
10.13039/501100001809-National Natural Science Foundation of China (Grant Number: U22A2044 and 62206063);
Local Innovative and Research Teams Project of Guangdong Special Support Program of China (Grant Number: 2019BT02X353);
10.13039/501100004543-China Scholarship Council (Grant Number: 202208440312)
Quadratic filtering for linear stochastic systems with dynamical bias under amplify-and-forward relays: Dealing with non-Gaussian noises
Get PDFIn this paper, the recursive quadratic filtering problem is investigated for a class of linear non-Gaussian systems with dynamical bias and amplify-and-forward relays. The stochastic bias, characterized by a dynamical process with certain non-Gaussian noises, is incorporated into the system state equation. An amplify-and-forward relay is utilized in the sensor-to-filter network channel to enhance signal transmission performance. The transmission powers of the sensor and relay are governed by two sets of random variables. Particular attention is given to the design of a quadratic filter in the presence of the dynamical bias, the amplify-and-forward relay, and non-Gaussian noises. For this purpose, an augmented system is constructed by aggregating the augmented state (comprising the original state and the associated bias) and its second-order Kronecker power. Consequently, the addressed quadratic issue for the underlying non-Gaussian system is reformulated as a linear filtering problem for the augmented system. Using difference equations, the filtering error covariance is derived and subsequently minimized through the design of an appropriate gain matrix. Moreover, sufficient conditions are established to ascertain the existence of the lower and upper bounds on the filtering error covariance. Finally, the effectiveness of the designed quadratic filtering algorithm is demonstrated through a numerical example.This work was supported in part by the National Natural Science Foundation of China under Grants 61933007, U21A2019, 62222312 and 62273005, the National Key Research and Development Program of China under Grant YS2022YFB4500205, the Natural Science Foundation of Shandong Province of China under Grant ZR2021MF088, the Hainan Province Science and Technology Special Fund of China under Grant ZDYF2022SHFZ105, the Fundamental Research Funds for the Central Universities of China, the Royal Society of the UK, and the Alexander von Humboldt Foundation of Germany
Secure State Estimation for Artificial Neural Networks With Unknown-But-Bounded Noises: A Homomorphic Encryption Scheme
Get PDFThis article is concerned with the secure state estimation problem for artificial neural networks (ANNs) subject to unknown-but-bounded noises, where sensors and the remote estimator are connected via open and bandwidth-limited communication networks. Using the encoding-decoding mechanism (EDM) and the Paillier encryption technique, a novel homomorphic encryption scheme (HES) is introduced, which aims to ensure the secure transmission of measurement information within communication networks that are constrained by bandwidth. Under this encoding–decoding-based HES, the data being transmitted can be encrypted into ciphertexts comprising finite bits. The emphasis of this research is placed on the development of a secure set-membership state estimation algorithm, which allows for the computation of estimates using encrypted data without the need for decryption, thereby ensuring data security throughout the entire estimation process. Taking into account the unknown-but-bounded noises, the underlying ANN, and the adopted HES, sufficient conditions are determined for the existence of the desired ellipsoidal set. The related secure state estimator gains are then derived by addressing optimization problems using the Lagrange multiplier method. Lastly, an example is presented to verify the effectiveness of the proposed secure state estimation approach.10.13039/501100001809-National Natural Science Foundation of China (Grant Number: 61933007 and U21A2019);
Science and Technology Development Fund, Macau, SAR (Grant Number: 0123/2022/AFJ and 0081/2022/A2);
University of Macau (UM) Talent Program (Grant Number: UMTP2023-PF01-0046);
Shanghai Pujiang Program (Grant Number: 22PJ1411700);
10.13039/501100002858-China Postdoctoral Science Foundation (Grant Number: 2023M732322);
Hainan Province Science and Technology Special Fund of China (Grant Number: ZDYF2022SHFZ105);
Royal Society of the U (Grant Number: 0000DONOTUSETHIS0000.K);
Alexander von Humboldt Foundation of Germany
Posthospitalization COVID-19 cognitive deficits at 1 year are global and associated with elevated brain injury markers and gray matter volume reduction
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Individual-level data and samples from the COVID-Clinical Neuroscience Study are available for collaborative research by application through the NIHR BioResource Data Access Committee https://bioresource.nihr.ac.uk/using-our-bioresource/apply-for-bioresource-data-access/. The Committee decide on academic applications, with escalation to the NIHR BioResource Steering Committee for contentious applications, and/or applications from industry. Participants in the NIHR BioResource have all consented to the sharing of de-identified data with bona fide researchers worldwide, for research in the public interest. There are limits to these consents both by expectation and legal—some datasets may not be shared beyond a safe setting in the UK. The Data Access Committee aim to process data-only requests as quickly as possible and meet fortnightly to consider applications. Once approved, timeframes for data availability vary from 2 weeks to 6 months depending on the nature of the data requested.Code availability:
Code is publicly available via https://github.com/tnggroup/covidcns.Extended data are available online at: https://www.nature.com/articles/s41591-024-03309-8#Sec24 .Supplementary information is available online at: https://www.nature.com/articles/s41591-024-03309-8#Sec25 .The spectrum, pathophysiology and recovery trajectory of persistent post-COVID-19 cognitive deficits are unknown, limiting our ability to develop prevention and treatment strategies. We report the 1-year cognitive, serum biomarker and neuroimaging findings from a prospective, national study of cognition in 351 COVID-19 patients who required hospitalization, compared with 2,927 normative matched controls. Cognitive deficits were global, associated with elevated brain injury markers and reduced anterior cingulate cortex volume 1 year after COVID-19. Severity of the initial infective insult, postacute psychiatric symptoms and a history of encephalopathy were associated with the greatest deficits. There was strong concordance between subjective and objective cognitive deficits. Longitudinal follow-up in 106 patients demonstrated a trend toward recovery. Together, these findings support the hypothesis that brain injury in moderate to severe COVID-19 may be immune-mediated, and should guide the development of therapeutic strategies.Members of the COVID-CNS Study Group are supported to conduct COVID-19 neuroscience research by the UK Research and Innovation/Medical Research Council (UKRI/MRC; grant no. MR/V03605X/1). G.K.W. is funded by the UK NIHR as an NIHR Academic Clinical Fellow (ACF-2022-07-007). B.D.M., G.B. and other investigators are supported by NIHR Health Protection Research Unit in Emerging and Zoonotic Infections at University of Liverpool, NIHR/Wellcome Trust King’s Clinical Research Facility, NIHR Maudsley Biomedical Research Centre at South London, Maudsley NHS Foundation Trust and King’s College London. B.D.M. is also supported for additional neurological inflammation research due to viral infection by grants from: the NIHR (award CO-CIN-01), the MRC (MC_PC_19059), the UKRI/MRC (MR/V007181/1), MRC (MR/T028750/1) and Wellcome (ISSF201902/3). J.-P.T. is supported by the Newcastle NIHR Biomedical Research Centre and the NIHR Dementia Translational Research Collaboration. This publication was supported by the Association of British Neurologists, British Paediatric Neurology Association, British Association of Stroke Physicians and the Royal College of Psychiatrists
The problems and potential for emotional labour in occupational therapy
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Data is available for this article.The Royal College of Occupational Therapists (RCOT) Workforce Survey (2023) provided a worrisome snapshot of the professional challenges faced by over 2600 Occupational Therapists working in the United Kingdom. Organisational stressors such as staff shortages, increased caseloads, insufficient support from managers, as well as personal stressors such as burnout, poor work–life balance and a lack of fulfilment pose a threat to the career longevity and well-being of Occupational Therapists. Despite these troubling data, most survey respondents were positive about the profession itself in terms of feeling enthused about service delivery (79%) and rewarded by their career (93%). Hence, the overarching message is somewhat bittersweet; despite unrelenting working conditions, Occupational Therapists continue to be passionate about providing good-quality person-centred care to clients. This active expression of passion for the profession in this landscape could be explained by the concept of emotional labour, which refers to how employees manage their feelings and expressions during social interactions to meet job-based goals (Grandey and Gabriel, 2015; Hochschild, 1983). Emotional labour has been found to be critical to professional practice in a range of healthcare settings including clinical medicine, nursing and social care (Reily and Weiss, 2016). Nevertheless, emotional labour has received scant attention in Occupational Therapy. The purpose of this editorial is to highlight the main characteristics, issues and opportunities associated with emotional labour in Occupational Therapy research and practice.This project was funded by the Brunel Research Initiative and Enterprise Fund (BRIEF) at Brunel University London (PI: Rebecca F Hings)
Heat and carbon monoxide exposure: Is two better than one?
Get PDFEditorial viewpoint.A fundamental aim in the field of human physiology is to understand and delineate the limits of human function. In the realm of exercise physiology, sports and aerobic performance, the preceding decades have been marked by investigation into exogenous mechanisms of blood doping, exemplified by the administration of recombinant erythropoietin (EPO), erythropoiesis stimulating agents and whole blood transfusion. Yet, the line between such ‘artificial’ methods of blood doping and natural adaptation becomes blurred as we better understand how to manipulate haematological parameters through methodologies currently allowed by international sporting committees.The presented work was performed in absence of external funding
Interactive effects of APOE ɛ4 status and vascular burden on white matter microstructural integrity in aging with and without neurocognitive decline
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Data are available from the corresponding author on request.Supplementary Material is available online at: https://journals.sagepub.com/doi/10.1177/13872877251320660#supplementary-materials .Background:
Carrying the Apolipoprotein (APOE) ε4 allele lowers age of onset and increases Alzheimer's disease (AD) risk. Neuropathological findings suggest a mixed etiology in many AD patients, and vascular pathology is common.
Objective:
This study tested the interactive effect of APOE status and multiple vascular comorbidities on white matter (WM) microstructure in aging and early AD.
Methods:
195 participants from the VPH-DARE@IT dataset were stratified in low/high vascular burden based on the Framingham Risk Score (BMI version). Tract-based spatial statistics was used for WM analyses.
Results:
There was a main effect of APOE, with APOE ɛ4 carriers having higher fractional anisotropy (FA) and lower axial diffusivity (AxD), mean diffusivity (MD), and radial diffusivity (RD) than non-carriers. There was a main effect of vascular burden with lower FA and higher AxD, MD, and RD in the high-burden than the low-burden group. A significant interaction between APOE genotype and vascular burden was also found for all diffusion indices. Post-hoc comparisons revealed lower left hemisphere WM integrity when comparing the low risk group (i.e., non-carriers low burden) to intermediate risk groups (i.e., non-carriers high burden or ɛ4 carriers low burden). The contrasts between the two intermediate risk groups showed altered WM integrity bilaterally. Only the non-carriers high burden showed greater alterations in WM integrity when compared with the high risk group (i.e., ɛ4 carriers high burden) mainly in right hemisphere tracts.
Conclusions:
These findings indicate an interactive effect of a risk gene and vascular comorbidities on WM integrity in aging and early AD.The current study was supported through funds from the European Union Seventh Framework Programme (FP7/2007–2013) – under Grant Agreement no. 601055, to AV and HS. AV is supported by funding obtained under the National Recovery and Resilience Plan (NRRP), Mission 4 Component 2 Investment 1.3 - Call for tender No. 341 of 15/03/2022 of Italian Ministry of University and Research funded by the European Union – NextGenerationEU, Project code PE0000006, Concession Decree No. 1553 of 11/10/2022 adopted by the Italian Ministry of University and Research, CUP D93C22000930002, “A multiscale integrated approach to the study of the nervous system in health and disease” (MNESYS)
Understanding lived experiences and perceptions of resilience in black and South Asian Muslim children living in East London: a qualitative study protocol
Get PDFSTRENGTHS AND LIMITATIONS OF THIS STUDY: ⇒The study will use embodied and qualitative research methods to provide insights into experiences and perceptions of resilience in a population typically excluded from resilience research. ⇒Findings will be analysed through a socioecological lens to show the importance of a systems approach for supporting children’s resilience. ⇒The use of arts- based and participatory methods with children and parents/carers will provide a creative, accessible and participant- led approach to data collection and will allow for multiple informants’ perspectives to be captured. ⇒Excluding non- English speakers means we cannot compare the different experiences that they likely have compared with English- speaking individuals and families.Supplementary Data are available online at: https://bmjopen.bmj.com/highwire/filestream/317039/field_highwire_adjunct_files/0/bmjopen-2023-082346supp001_data_supplement.pdf .Introduction: It is important to promote resilience in preadolescence; however, there is limited research on children’s understandings and experiences of resilience. Quantitative approaches may not capture dynamic and context-specific aspects of resilience. Resilience research has historically focused on white, middle-class Western adults and adolescents, creating an evidence gap regarding diverse experiences of resilience in middle childhood which could inform interventions. East London’s Muslim community represents a diverse, growing population. Despite being disproportionately affected by deprivation and racial and cultural discrimination, this population is under-represented in resilience research. Using participatory and arts-based methods, this study aims to explore lived experiences and perceptions of resilience in black and South Asian Muslim children living in East London.
Methods and analysis: We propose a qualitative study, grounded in embodied inquiry, consisting of a participatory workshop with 6–12 children and their parents/carers to explore lived experiences and perceptions of resilience. Participants will be identified and recruited from community settings in East London. Eligible participants will be English-speaking Muslims who identify as being black or South Asian, have a child aged 8–12 years and live in East London. The workshop (approx. 3.5 hours) will take place at an Islamic community centre and will include body mapping with children and a focus group discussion with parents/carers to explore resilience perspectives and meanings. Participants will also complete a demographic survey. Workshop audio recordings will be transcribed verbatim and body maps and other paper-based activities will be photographed. Data will be analysed using systematic visuo-textual analysis which affords equal importance to visual and textual data.
Ethics and dissemination: The Queen Mary Ethics of Research Committee at Queen Mary University of London has approved this study (approval date: 9 October 2023; ref: QME23.0042). The researchers plan to publish the results in peer-reviewed journals and present findings at academic conferences.This work was supported by Barts Charity, UK (charity number: 212563, project code: MRC&U0042)
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