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Free-space optical communications at 4 Gbit/s data rate with a terahertz laser
No full textTerahertz-frequency (THz) carrier waves in free-space optical (FSO) communications offer the potential for > 1 Tbit/s data rates and stable latency. They offer wider bandwidths than available in the microwave region, together with reduced scattering and relaxed pointing requirements compared with visible and near-infrared regions. However, 1–10 THz FSO communications systems have thus far been limited to data rates several orders of magnitude lower than those of infrared systems. This work describes an experimental demonstration of multi-gigabit-per-second FSO communication using a THz quantum cascade laser (QCL), opening a new frontier for next-generation wireless communications. The FSO communication system consists of a 2.4 THz QCL source as the transmitter and a room-temperature Schottky barrier diode detector as the receiver. By directly modulating the terahertz QCL, we achieved non-return-to-zero on-off keying (NRZ-OOK) with a transmission rate of up to 4 Gbit/s. We evaluated the performance of the communication link by analyzing the bit error rate (BER) of the demodulated signal at the receiver while examining its relation to received optical power, QCL modulation power, and various bias points. Our work establishes the foundation for high-speed optical wireless communication based on terahertz QCL technology systems
Unveiling neural mechanisms in Lewy body dementia using advanced neuroimaging techniques
No full textLewy body dementia (LBD) is an umbrella term, including both Dementia with Lewy bodies (DLB) and Parkinson’s disease dementia (PDD). It is the second most common neurodegenerative disorder, characterised by cognitive impairment, Parkinsonism and marked neuropsychiatric symptoms. It is associated with significant frailty, morbidity, and carer stress. Despite this, evidence-based treatments to manage symptoms are limited and a disease modifying treatment remains elusive. A key contributing factor is the lack of clinically meaningful neuroimaging markers. Conventional neuroimaging methods such as structural MRI have thus far had limited utility because they mostly focus on measures of loss of volume and cortical thickness, which is heterogeneous in Lewy body disorders. Therefore, there is an urgent need to identify useful neuroimaging markers in LBD.
In this thesis, I will use more advanced neuroimaging analysis techniques such as Quantitative Susceptibility Mapping (QSM), neuroanatomical normative modelling, brain ageing and Fixel based analysis (FBA) in patients with Lewy body disorders, to better understand underlying disease mechanisms and determine whether neuroimaging metrics derived from these techniques have clinical promise.
Considering disease mechanisms, QSM measures local magnetic susceptibility and can provide information on underlying tissue composition. I use this method to shed further light on whether DLB and PDD are the same condition or distinct, as this is a current controversy in the field. Using MRI data derived from thalamic segmentation combined with FBA, I unveil novel findings about the neural underpinnings of depression in Lewy body disorders.
I also apply neuroanatomical normative modelling and the brain-age paradigm to T1-weighted structural MRI data. These methods may be more sensitive to detecting brain changes compared to conventional structural MRI analysis techniques especially when atrophy patterns are disparate, as is the case in people with Lewy body disorders. Overall, I will show that key neuroimaging metrics derived from these techniques are clinically relevant and potentially translational
Structural protection of ship-shaped offshore installations using hollow-section rubber fenders under high-energy side-by-side collisions
No full textThis study investigates the effectiveness of hollow-section rubber fenders in mitigating structural damage during high-energy collisions between a ship-shaped offshore installation and a shuttle tanker engaged in side-by-side offloading operations. Axial crushing tests were carried out on physical models at loading speeds ranging from quasi-static to dynamic conditions to evaluate the energy-absorption capacity of the rubber fenders, with particular attention to strain-rate effects. A finite element model of the fenders was developed and validated through comparison with the experimental data. The numerical analyses were performed using LS-DYNA, a commercial finite element analysis package. The validated model was then applied to simulate high-energy collision scenarios involving a Suezmax-class shuttle tanker and a very-large-crude-carrier (VLCC)-class offshore installation, both with and without rubber fenders. The principal novelty of this study lies in the development of a computational modelling approach capable of accurately predicting the strain-rate-dependent energy absorption behaviour of hollow-section rubber fenders under realistic collision conditions
Keeping your Curriculum Broad and Balanced: Celebrating the Arts and Humanities in Primary Schools
No full textThis document includes the summaries of the keynote talks and workshops for the HHCP in-person conference, taking place on 19 November 2026 at the British Library. This conference explores the vital role of the arts and humanities in primary education at a time when schools face increasing pressure to prioritise core subjects. The conference has a truly stellar line up of speakers including award-winning children’s book author and illustrator Lauren Child; Yidan prize winner Usha Goswami, Professor of Cognitive Developmental Neuroscience at the University of Cambridge; Chris Haughton, children’s author, illustrator, and designer; Pete Moorhouse, creative illustrator; and Tara Page, creative pedagogy and research expert. Through research insights and practical workshops speakers will share approaches and experiences. To register, visit: https://www.bloomsburytheatre.com/event/2026/11/hhcp-conference-2026
An autonomous network of acoustic detectors to map tiger risk by eavesdropping on prey alarm calls
No full textTiger (Panthera tigris) attacks are a frequent source of injuries and fatalities among villagers in Nepal, where many communities make extensive use of dense forests for foraging and grazing of livestock. As conservation efforts have boosted the tiger population in the country, a conflict exists between maintaining traditional practises whilst ensuring human safety and protecting endangered predators. Hence, there is a need for cost-effective management strategies that do not reduce habitat use by humans or wildlife. Passive acoustic monitoring (PAM) offers a promising approach to mapping tiger presence in real-time and providing a warning system for villagers. Although tigers vocalize infrequently, their presence triggers alarm calls from prey species, meaning these alarm calls could potentially act as a proxy for detecting tigers. To explore the potential for tracking tigers and other dangerous predators such as leopards using these alarm calls, we designed and tested a PAM system in the Terai region of southern Nepal. We implemented a TinyML low-memory convolutional neural network (~1000 parameters) for chital deer (Axis axis) automatic detection—a species that reliably produce loud predator-specific alarm calls—and deployed a distributed network of 10 autonomous interconnected sensors for continuous operation over 3 months. The network transmits chital deer alarm call events via a cellular-connected gateway to a remote base station to generate a heatmap of predator risk. Incidences of high predator risk can be used to alert local forest rangers, who can then inform nearby villagers of areas with a higher likelihood of predator presence. The neural net achieved an F1 score of 0.91 in training and 0.72 in the field. We suggest that this proof of concept indicates that automated PAM could be an effective tool for detecting and tracking tigers and other predators and a potentially valuable tool for facilitating human-wildlife co-existence
Wetland Expansion Reduces CO2-Equivalent Emissions and Strengthens the Congo Basin's Role as a Net Carbon Sink
No full textWetlands are the largest natural source of methane, yet their desiccation releases substantial amounts of carbon dioxide. Changing wetland emissions provide the greatest source of uncertainty in global emissions estimates due to limited data for key tropical carbon sources and sinks, including the Congo Basin. Here we quantified changing swamp forest hydrology, forest productivity and greenhouse gas emissions between 2007 and 2024 using satellite Earth observation and emissions datasets. We show that swamp forests expanded from 195,345 km
2
to 222,467 km
2
between 2007 and 2024, demonstrating a reversal of previously reported long‐term drying trends. The observed wetting trend increased productivity in both swamp and
terra firme
forests. Despite increasing methane emissions, wetland expansion reduced CO
2
‐equivalent emissions by 2 (95% CI; −2.94 to −1.12) million tonnes per year since 2007, highlighting the region's increasing role as a net carbon sink and its significance for global carbon budgets
Multidisciplinary team interpretation performance for indeterminate bone uptake on PSMA PET during prostate cancer staging: Comparison with PROMISE criteria
No full textPURPOSE: To compare the performance of a multidisciplinary team (MDT) with the proposed standardized PROMISE classification system for indeterminate bone uptake on staging PSMA PET. METHODS: 744 staging PSMA PET/CT scans (140 18F-PSMA-1007 and 604 68Ga-PSMA-11 PET/CT) were retrospectively reviewed for the presence of indeterminate bone metastatic staging. 95 scans which were discussed at an MDT meeting were further analysed for the comparison with the PROMISE classification system. MDT interpretation of the bone staging was recorded as positive or negative, based on risk stratification, imaging review, and clinically suitable management options. Additional resources were occasionally used, such as bone biopsy, musculoskeletal MRI, or re-evaluation after initial androgen deprivation therapy. MDT and PROMISE classification were compared for agreement. Statistical assessment was made on any differences in age, PSA, T-stage, Gleason score, risk, SUVmax and tracer used between negative and positive patients in both methods. Discordant cases were correlated with follow up data. RESULTS: The overall incidence of indeterminate bone uptake in staging PSMA PET scans was 16.9%, reaching 40% for 18F-PSMA-1007. There was substantial agreement between MDT and PROMISE interpretation (87.3%). The MDT was more likely to interpret an indeterminate bone uptake as negative in patients with lower Gleason score and in scans where 18F-PSMA-1007 was used. The data from long-term follow up favoured the MDT interpretation in all the cases of disagreement. Examples of pitfalls in rib or thoracic spine foci of uptake are presented and recommendations for PET reporters and MDTs have been generated based on the results. CONCLUSION: PROMISE may interpret indeterminate bone PSMA uptake with high accuracy. Therefore, PET reporters are recommended to use the PROMISE algorithm, while being mindful of common pitfalls related to the Gleason score, tracer used and anatomical localisation of indeterminate bone findings. Additional discussion in an MDT meeting is recommended with a view to resolve all equivocal findings
Standing in Trusts Law, the Beneficiary Principle and the Juridical Nature of Trustee Duties
No full textRetrospective Validation of Invalid Trustee Appointments and Subsequent Acts in the Operation of the Trust
No full textInterpreting peripheral oxygen saturation variability in critical illness: A directional framework adjusted for hypoxia severity
No full textPeripheral oxygen saturation (SpO2 ) exhibits a complex pattern of fluctuations during hypoxia, which can be quantified using entropy measures. SpO2 entropy analysis provides insights into dynamic physiological regulation by non-invasively reflecting the body’s capacity to adapt to internal or external physiological challenges. However, the interpretation of SpO2 entropy alone is limited without contextualisation and the degree of physiological challenge encountered (e.g. the severity of hypoxia). This proofof-concept retrospective study analysed continuous 1 Hz SpO2 recordings extracted from MIMIC-III dataset’s Intensive Care Unit ICU patients with sepsis (n = 164), chronic obstructive pulmonary disease (COPD) (n = 58), acute liver failure (ALF) (n = 59), or cirrhosis (n = 169). Sample entropy was computed directly from raw 20- min SpO2 signals and normalised to mean SpO2 using directional parenclitic deviation (δ), derived from a healthy hypoxia-exposure reference dataset. Cox-regression models assessed 30-day ICU mortality. In sepsis, δ was significantly higher in non-survivors (hazard ratio (HR) = 2.20, P < 0.0001) and independently predicted 30-day mortality (HR = 1.79, P < 0.0001). δ was not predictive in the COPD, ALF and cirrhosis cohorts. Unlike other patient groups, the cirrhosis group demonstrated unexpected mean negative δ values, suggesting aberrant regulatory engagement, potentially related to the pathophysiology of hepatopulmonary syndrome. These findings demonstrate that δ provides physiological contexts to entropy-based SpO2 analysis. By linking variability to the severity of hypoxia, this framework enables a more interpretable and a potentially clinically applicable biomarker of systemic regulation in critical illnesses. Future validation across diverse cohorts could support its potential to aid in personalised care within intensive care settings