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State-of-the-Art emerging materials under a terahertz emission spotlight
No full textThe generation and manipulation of photoinduced transient currents, as well as characterization of the emission of resultant electromagnetic waves, are crucial for the design and coherent operation of advanced optoelectronic devices. An ultrafast optical pulse-driven transient photocurrent lasts for picosecond time scale bursts as a terahertz (THz) emission. The emitted radiation, permitted by the intrinsic structural properties of materials, is remarkably enriched with information on associated ultrafast transients and can potentially explore microscopic insights into fascinating nonlinear dynamical characteristics. This review aims to understand terahertz (THz) emission and the underlying ultrafast photophysics in contemporary matter systems. Since THz emission is the manifestation of photocurrents and induced dynamic polarization that sustain a picosecond time scale, it offers a noncontact and noninvasive platform for studying such ultrafast phenomena
Fluorescence-lifetime optical electrophysiology in contracting cardiomyocytes
Get PDFPrecise monitoring of cardiac electrophysiology in vitro is crucial to understanding heart function and cardiac disease. However, high-throughput, contact-free methods for directly measuring excitation-contraction coupling remain limited. Here, we introduce a new paradigm for quantitative electrophysiological imaging that combines fluorescence lifetime and intensity information to capture dynamic cardiac signals with high fidelity. We show that lifetime measurements are intrinsically decoupled from motion artifacts and provide calibrated calcium concentration and membrane potential readouts across wide fields of view. Using a gated single-photon avalanche diode camera, we acquire fluorescence lifetime images at up to 200 frames per second with sufficient signal-to-noise ratio such that each frame contains meaningful lifetime information without temporal averaging. This approach yields spatially resolved maps of absolute voltage and calcium values across contracting cardiomyocyte monolayers, revealing heterogeneous cell behaviors within individual assays and uncovering previously unreported dynamics during late-phase repolarization for real-time analysis of excitation-contraction coupling
Beyond bitrate: understanding the QoE impact of playback rate and seeking in adaptive video streaming
Get PDFQuality of Experience (QoE) is a key component in adaptive bitrate (ABR) streaming. While the effects of delivery disruptions - such as changes in video quality or rebuffering - have been extensively studied, the impact of playback rate variations remains relatively unexplored. Existing work has examined the QoE impact of playback rate in isolation, without comparing it to other common ABR streaming artifacts such as video quality variations, rebuffering, or seeking. Moreover, the role of gradual playback rate transitions has not been explored. This paper addresses these gaps through four large-scale subjective studies that provide a systematic QoE evaluation of playback rate. We compare the acceptability of playback rate changes against quality degradations and rebuffering, and assess rate increases relative to seeking, both of which are strategies for maintaining the desired latency in low-latency streaming. We further investigate how gradual versus instantaneous playback rate transitions affect QoE. Through our subjective studies we identify levels of slowed-down playback that are imperceptible to users, and can be combined with video quality adaptation in ABR algorithms to reduce rebuffering. Moreover, we identify imperceptible rates of speeded-up video playback, which can be used as part of catch-up mechanisms to maintain a desired latency in live streaming, offering a less detrimental alternative to seeking events, which we found to significantly degrade QoE. This work presents the first systematic comparison of playback rate variations with video quality degradation, rebuffering, and seeking. The findings extend our understanding of QoE in adaptive video streaming and provide actionable design guidelines for video players to improve the user experience of streaming services
"You don’t need to be a conspiracist to have concerns" - the imperative of proactive conversations
No full text‘X-minute city’ has been entangled with conspiracy theories but not all scepticism is unfounded. The question then is how to respond to the justified critical voices, given the academic world is already debating and critiquing various aspects of the x-minute city ideas. Drawing on two brief examples of policy and research communication, more specifically the Scottish Government’s recent planning strategies and guidance on 20 minute neighbourhoods and local living and a collection of articles touching on x-minute city on ‘The Conversation’ respectively, this viewpoint discusses how the professional and academic communities can facilitate more proactive and constructive conversations with the sensible applications and discussions of the x-minute city ideal
Between privileged dependence and precarious autonomy: class and gender in Chinese students’ experiences in international education
Get PDFThis article examines how social class and gender intersect to shape educational experiences and aspirations of Chinese international postgraduate students’ in the UK. Drawing on qualitative longitudinal research with 25 Chinese taught postgraduate students, the study explores how family socio-economic background structures access to financial, cultural and social resources over one academic year. Using the concepts of ‘privileged dependence’ and ‘precarious autonomy’, the findings demonstrate that middle-class students benefit from sustained parental support, whereases working-class students experience autonomy as economically constrained and risk-laden. Beyond the influence of social class, these dynamics are also shaped intersectionally by sociocultural expectations around gender. The study thus conceptualises ‘privileged dependence’ and ‘precarious autonomy’ as dynamic ‘classed’ and ‘gendered’ processes, contributing to intersectional research on international student mobility
Challenges for the design of randomised trials for interventions for people with multiple long-term conditions: recruitment and outcome selection
Get PDFThe burden of multiple long-term conditions is significant for the individual and society. Exploring interventions to alleviate disease progression, accumulation of long-term conditions and symptom burden is crucial. This commentary debates two important considerations for intervention design and subsequent recruitment approaches
How reliable is visual lameness scoring? Assessing human label variability for use in automated detection systems
Get PDFVisual mobility scoring to detect lame dairy cattle can be subjective and inconsistent. This study assessed the reliability of visual mobility scores from multiple assessors, using different scoring methods (live vs. video) and experience levels to evaluate their influence on label quality for machine learning applications. We gathered data from two farms using the AHDB 4-point mobility scale and a simplified post-hoc dichotomised version, with both live and video assessments. Substantial within- and between-assessor variation was seen in scores, particularly for scores 0 and 1 (consistent with normal and slightly abnormal gaits, respectively). Assessors showed only fair (weighted kappa ≈ 0.33) score consistency when they scored the same animal in different ways (live vs. video). Post-hoc simplification of the four-level scores to a dichotomous score improved agreement but reduced granularity. Assessor experience had limited influence on agreement levels (P > 0.05), and increased video viewing frequency during the assessment process was associated with lower inter-assessor agreement (probability estimate = −0.49, P = 0.005), suggesting higher uncertainty in ambiguous cases. Qualitative feedback from assessor comments revealed that the speed of the animal affected their scoring decisions (β = –1.92, P = 0.007). These results highlight the difficulties in using subjective human scores as labels for machine learning training. To improve automatic lameness detection in dairy cattle, we need strategies to reduce this variation and use more definitive labels
Teaching undergraduate special care dentistry in the UK and Ireland: What? How? When? How much? Who?
Get PDFIntroduction:
New dental graduates are expected to have acquired the skills and behaviours to provide dental care for the population they serve. An ageing population and advances in medicine mean that there are increasing numbers of patients who may require Special Care Dentistry. Special Care Dentistry is the branch of dentistry concerned with access to equitable oral healthcare for people with disabilities and those who are disadvantaged. This study aimed to explore the teaching of Special Care Dentistry (SCD) within undergraduate (UG) dental curricula in the UK and Ireland.
Materials and Methods:
A cross-sectional online survey was distributed to all SCD teaching leads within 18 universities delivering undergraduate dental curricula in the UK and Ireland. Respondents described their curriculum, teaching and assessment, as well as the barriers and facilitators they faced. Qualitative responses were collected as open-ended text within the survey and coded independently by two authors.
Results:
From 12 respondents (67% response rate), the average time given to SCD during training over the whole UG programme was reportedly 47.4 h. While 83% (n = 10) reported that students observed treatment delivery for special care patients, only 50% (n = 6) reported actual student-delivered care. Almost all (n = 10) applied the International Association of Disability and Oral Health curriculum, as recognised by the Association of Dental Education Europe (ADEE). Attitudes towards SCD from academic staff outside of the specialty were seen as the biggest barrier to SCD teaching, whereas the availability of academic staff and emphasis on SCD within the curriculum were facilitators.
Discussion:
The teaching of SCD in dental schools in the UK and Ireland is markedly varied, with respondents highlighting barriers to the delivery of teaching and learning in this area.
Conclusions:
There is a persistent need to standardise undergraduate exposure to patients requiring Special Care Dentistry across Ireland and the UK. This will equip the future dental profession to adequately and equitably care for the whole of society, regardless of ability
Large-scale and cost-effective fabrication of ultra-thin, biodegradable microelectrode arrays and pressure sensors using laser micromachining
No full textThis paper addresses the critical need for innovative fabrication strategies to advance wearable and implantable medical devices, emphasizing versatility, cost-effectiveness, scalability, and large-scale manufacturability. Specifically, the focus is on bioresorbable electronic devices like microelectrode arrays (MEAs), crucial for intracerebral neural recording and electrical stimulation, and implantable pressure sensors necessitating flexible and cytocompatible properties to enhance tissue compliance and minimize the risk of rejection. Traditional cleanroom-based techniques have limitations in compatibility with most of the bioresorbable materials. To overcome this challenge, a mask-free, contact-less, and scalable fabrication strategy utilizing an advanced UV-based laser system is proposed. The approach successfully demonstrates fabrication of flexible, cytocompatible, and biodegradable MEAs and pressure sensors. A biodegradable substrate is prepared using cost-effective and transparent biodegradable material, i.e., chitosan, with biodegradable Zinc (Zn) electrodes. Electrochemical impedance spectroscopy (EIS) analysis reveals an impedance of 10 kΩ at 1 kHz. Also, as-prepared chitosan exhibits good tensile strength and excellent cytocompatibility with smart muscle cells, demonstrating its suitability for implantable applications. The manufactured MEAs exhibit excellent stability under multiple bending angles, proving their reliable performance when interfacing with tissues. Furthermore, the fabricated electrodes are fully degraded in less than 2 days in phosphate-buffered saline (PBS) solution, demonstrating excellent biodegradability
A systematic review of entomological outcomes and sampling approaches used in the evaluation of cluster randomised controlled trials for malaria vector control product
No full textBackground:
Entomological outcomes are critical for understanding the biological mechanisms and operational performance of malaria vector control interventions. However, the quality and consistency of how these outcomes are measured and reported in cluster randomised controlled trials (cRCTs) is unclear. We conducted a systematic review of design features, sampling methods, and metrics used for measuring entomological outcomes in malaria vector control cRCTs. Our aims were to assess the consistency and quality of entomological study designs and examine how key design features influence the precision of reported entomological effect sizes.
Methods:
Malaria cRCTs in the published literature were identified in four databases and two trial registries. We extracted information on entomological outcomes measured, entomological sampling strategies and trial design features. To evaluate overall design quality, we created an Entomological Study Design Risk (ESDR) metric that assessed trials across four domains related to power analysis and sampling design; with domain ratings combined to generate an overall ESDR score. We also used a linear mixed-effects model (LMM) to examine how the use of power analysis and the number of clusters and sampling points in entomological sampling influenced the precision of main entomological outcomes.
Results:
Sixty-two cRCTs of malaria vector control interventions were identified between 1992 and 2021; with 74% being conducted in Africa. Thirteen different entomological outcomes and 12 sampling methods were used across trials: with considerable variation in the frequency of entomological sampling within trials. In total, 70% of the cRCTs were categorized as having high potential entomological design risk based on a combination of the lack of power analyses and inadequate or unclear randomisation of sampling points. The only significant predictor of the precision of entomological outcomes was the number of entomological clusters in which data were collected (greater precision as cluster number increased).
Conclusions:
There is substantial variation in how entomological outcomes are measured and reported in cRCTs, and limited incorporation of key design features such as power analysis and random selection of sampling points for outcome measurement. Standardization where possible and clearer reporting guidelines for entomological components are therefore needed to improve the quality, comparability, and policy relevance for future trials
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