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The protein homeostasis of SPATULA coordinates seed thermoinhibition response in Arabidopsis thaliana
No full textSupraoptimal temperature (SOT) suppresses the completion of seed germination (termed thermoinhibition) to ensure seedling establishment under favorable environmental conditions. SOMNUS (SOM) plays a crucial role in suppressing seed germination completion under SOT, although the underlying regulatory mechanism governing this process remains elusive. In this study, we identified that a bHLH transcription factor SPATULA (SPT) directly binds to the promoter region of SOM, thereby activating its expression. Notably, knockout mutants of SPT enhanced the completion of seed germination under SOT, characterized by increased GA and decreased ABA biosynthesis. In contrast, SPT overexpression reduced the completion of seed germination, leading to decreased GA and increased ABA biosynthesis. These results suggest that SPT negatively controls the seed thermoinhibition response. Genetic analyses further showed that SOM acts epistatically to SPT in suppressing the completion of seed germination under SOT conditions. Furthermore, our findings suggest that the E3 ligase COP1 possibly mediates the degradation of SPT in the nucleus. Under SOT conditions, COP1 is translocated from the nucleus to the cytoplasm, stabilizing nuclear SPT and activating SOM expression to initiate seed thermoinhibition. In a DEX-inducible system, artificial retention of nuclear COP1 induced the degradation of nuclear SPT, limiting SOM expression and subsequently attenuating the seed thermoinhibition response under SOT conditions. These findings reveal a critical function of SPT in controlling the seed thermoinhibition response via SOM activation
Assessment of toxic metals and trace elements in breast milk of mothers and their health risks to infants: A cross-sectional study in Ardabil, Northwest Iran
No full textThis research aimed to assess the potential health risks for infants and measure the concentrations of heavy metal substances in the breast milk of mothers residing in Ardabil, Iran. The study was descriptive and cross-sectional in nature. Ten health centers in Ardabil City were selected for the research. The ages of participating mothers ranged from 19 to 39 years, and breast milk samples were collected from those who were 1-12 months postpartum. A 25-item questionnaire was used to evaluate the participants' exposure to heavy metals in their environment and diet. Data analysis was performed using the non-parametric Mann-Whitney U test, resulting in a p-value greater than 0.05. The average body mass index (BMI) of breastfeeding mothers was 26.26 ± 3.73. Spike recovery values ranged from 92 % to 106 %, indicating reliable performance within the ICP-MS range. The limit of detection (LOD) during routine sample analysis was 0.001 μg/L. The daily intake (DI) of lead (Pb), arsenic (As), and chromium (Cr) for infants was calculated. According to the findings, copper (Cu) had the highest average concentration in breast milk at 803.94 μg/L, while cadmium (Cd) had the lowest at 1.87 μg/L. Additionally, potassium (K) exhibited the highest average concentration at 490.49 mg/L, whereas molybdenum (Mo) had the lowest at 0.8 μg/L. The average daily intake of Pb, As, and Cr through breastfeeding was measured at 3.39, 0.799, and 3.47 μg/kg-bw/day, respectively. The results confirmed the presence of mercury (Hg), As, and Pb in every milk sample collected from lactating mothers in Ardabil, indicating potential exposure of infants to elevated levels of toxic heavy metals. [Abstract copyright: Copyright © 2025 Elsevier Ltd. All rights reserved.
Modelling and nonlinear analysis of frictional jointed beams with inerter-based dynamic vibration absorber
Get PDFThis study investigates the effectiveness of an inerter-based dynamic vibration absorber (IDVA) in suppressing vibrations in a nonlinearly jointed beam structure. The governing partial differential equations are derived and discretized using the finite element method, followed by transformation into ordinary differential equations via the Galerkin method. To efficiently compute the steady-state dynamic response and vibration power flow variables, the harmonic balance method with an alternating frequency–time (HB-AFT) scheme is employed. The results demonstrate that the proposed grounded IDVA design achieves superior vibration reduction and energy absorption compared to other designs. The nonlinear frictional joint exhibits distinct behaviour depending on the limit friction force: at smaller limit friction forces, the joint behaves as a frictional damper, resulting in lower response peaks and potential stick-slip motion at the beam tips; at larger limit friction forces, the joint acts as a stiffener, inducing full-stick behaviour and increasing the natural frequency. Additionally, the stiffness nonlinearity primarily influences the system response near the third and fifth resonant peaks, whereas the inertance value significantly affects the first resonant peak. The power dissipation characteristics vary with excitation frequency, with the IDVA dissipating the majority of energy between the first and second resonant frequencies. A design suggestion is to position the IDVA away from the fixed boundary to minimize both the dynamic response and the kinetic energy of the system
Transforming programming education: The effectiveness of motivational scenario-based design in serious games motivation, programming education, Scenario-Based Design (SBD), serious games, vocational education
Get PDFProgramming education faces persistent challenges, particularly in sustaining learner engagement and motivation while teaching abstract concepts like algorithms, data structures, and problem-solving skills. Traditional methods, focused heavily on theory, often fail to engage students effectively, resulting in high dropout rates, especially among novice programmers. This study proposed a Motivational Scenario-Based Design (MSBD), which integrates Scenario-Based Design (SBD) with Keller's ARCS motivational model to create an adaptive and personalised learning experience. The MSBD framework embeds programming tasks within game-based learning environments, supporting learners to apply abstract concepts in simulated real-world scenarios. The ARCS model sustains motivation throughout the learning journey by targeting Attention, Relevance, Confidence, and Satisfaction. As a proof of concept based on a case study, this study developed the serious game GhostCoder, incorporating Objective, Structural, and Adaptive Scenarios to guide learners from foundational programming concepts to advanced problem-solving skills. The experimental evaluation involving IT diploma students at a vocational institution demonstrated the efficacy of the MSBD framework. Pre-test and post-test assessments and the IMMS Survey showed statistically significant improvements in programming knowledge and learner motivation. The results indicate that MSBD effectively bridges the gap between theory and practice, enhancing engagement and learning outcomes. While further refinement of the adaptive learning features is needed, the study underscores the potential of MSBD to optimise serious games for novice programmers and other educational contexts
Impact of acoustic and informational noise on AI-generated clinical summaries
Get PDFObjectives: To investigate the effect of introducing environmental noise, microphone identity and position, and informational noise on the accuracy of a commercial Clinical AI Scribe (CAIS). Methods and analysis: Consultations on five medical conditions (memory loss, diarrhoea, headaches, skin rash or prostate symptoms) were recorded in a simulated primary care setting. A ground-truth audio file was produced, along with a ground-truth clinical summary via the CAIS. Different types of ‘noise’ at different levels were then investigated by (i) varying the type and distance of the microphone, (ii) introducing background noise (rain, baby, construction, toddler) at various levels and (iii) introducing informational noise (irrelevant discussions, medical and non-medical). These were then compared with the ground-truth summaries. The degradation of clinical summary accuracy was measured (omissions, hallucinations and inclusions), relative to the ground-truth summary. Results: Errors increased for all noise levels and noise types, principally being omissions. At 4.5 m from the consultation, for all microphones tested, all facts were omitted. At up to 2 m, all microphones, except the laptop, only introduced a small number (<5) of omissions. For background noise, the type of noise was found to correlate with omissions, with toddler and heavy rain being particularly deleterious. The CAIS was remarkably apt at rejecting additional informational noise. Conclusions: The CAIS generally excelled at capturing a doctor-patient consultation and producing accurate clinical summaries; however, error rate (especially omissions) increased notably when acoustic noise was introduced. The system was better able to handle informational noise
Delivering healthcare in multiprofessional teams: The negotiation of tasks
Get PDFMultiprofessional team working is assumed to be difficult. This is often associated to professional identity and jurisdiction. Despite anticipated difficulties, few studies examine teams working in their main arena: team meetings. One important function of these multiprofessional team meetings is to determine future tasks and next steps for patients. This paper examines the negotiation between professionals of what these next steps should be.Data was collected in 2018 and 2019, from three Community Learning Disability Teams in the UK, with a total length of 12 hours and 37 minutes. Conversation analysis (CA) was used to analyse 22 extracts, at points in the interactions when there were negotiations on the next steps the team should take for clients.Negotiations were characterised by propositions and counter propositions. They occurred when a course of action was proposed that made a specific professional’s role relevant, which were then countered by that professional. Countering was achieved by professionals separating themselves from the team, using first-person pronouns and making statements on their next steps. In both propositions and counters professionals orient to epistemics and deontics, important for how their turns-at-talk were receipted by other team members.This paper shows that instead of problematic, professional identity was used as a conversational resource. Negotiations are key for multiprofessional teams to determine optimal next steps for patients, and who could and should do specific tasks. Professionals orient to knowledge of professional identity to propose tasks that others could do, and to counter these propositions
Feasibility study of a home-based sensory training system (STS) device for type 1 complex regional pain syndrome in England: Lessons learnt
Get PDFIntroductionSensory discrimination training has demonstrated improvements in two-point discrimination and pain reduction in people with chronic pain. We tested the feasibility and acceptability of a novel Sensory Training System (STS) device in the homes of people with Type 1 Complex Regional Pain Syndrome (CRPS).MethodsParticipants meeting CRPS diagnostic criteria were invited to use the STS for a minimum of 30 minutes per day for 30 days. Device usage data were captured by the STS. Assessments at baseline and after 30 days were: two-point discrimination ability, pain intensity and interference, sensitivity and emotions towards CRPS limb. Qualitative interviews were conducted at the end of the study to capture participants' feedback on the device.ResultsA total of 10 participants (female n = 7) completed the study. Participants' mean age was 56.4 years (range: 24-78 years), and mean disease duration was 9.37 years (range: 4.25-26.5). Eight had lower limb CRPS. The mean STS device use was 27.3 ± 3.4 days and mean daily usage of training games was 00:27:11 ± 00:07:52 (hh:mm:ss). No patterns or trends were evident between device usage and outcome data.ConclusionThis feasibility study of a home-based STS for people with CRPS revealed key areas for improvement in the device's hardware and software and outlined the challenges of development and testing during the COVID-19 pandemic, while also capturing valuable usability insights from participant feedback. Key recommendations include early and ongoing collaboration with users, securing sufficient funding, ensuring correct device setup by participants, conducting interim analysis, and using online tools to enhance participant experience and data collection.Study registrationThe study was registered with ISRCTN registry on 28th May 2021 (https://doi.org/10.1186/ISRCTN89099843)
A sustainable water management framework for schools in Sub-Saharan Africa
No full textSafe and adequate water supply, sanitation, and hygiene (WASH) in schools are prerequisites within the right to basic education. WASH facilities across schools in developing nations, particularly in Africa, are unsatisfactory and expose children to risks of disease and infection. This study aims to gather insights into the WASH status of secondary schools in Ibadan, Nigeria, to develop a sustainable water management framework for schools. A concurrent mixed-method design (questionnaires and interviews) was adopted to benchmark water management in schools and inform the design of a framework. Results reveal a wealth of issues and concerns that include infrastructure challenges accessing reliable and safe water supplies, rundown and unhygienic toilet/urinal facilities, and dilapidated sinks/taps, plus resource challenges, such as an absence of tissue paper and soap. These issues are exposing schoolchildren to unnecessary health risks, further supported by reported illnesses and reduced school attendance. Based on these findings, and guided by the UN SDG#6 targets, a water improvement framework has been created and validated by school officials. The framework identifies both short-term and long-term guidance/actions to improve water management in schools across Sub-Saharan Africa. These form crucial steps toward better WASH, building healthier communities and enhancing educational environments and outcomes for schoolchildren
Evaluating argon and xenon ion thruster propellants and their interaction with atmospheric species at 360 km altitude
No full textMotivated by recent developments in the commercial sector related to the use of argon as a spacecraft propellant, this paper presents the first comparison between two ion thrusters using xenon and argon as propellants. We use numerical simulations to model a satellite at 360 km altitude, a typical Low-Earth Orbit, and so therefore include ambient gases as well as the propellant in our modelling. We use a hybrid particle-in-cell scheme in which the particle density determines whether interactions are simulated using a Monte Carlo collision or using a direct simulation Monte Carlo collision model. Plume shape, overall propulsive performance and interactions between the ionized propellant, ambient species and the satellite’s surface are considered here. Our calculations indicate that argon produces a 67.1% higher specific impulse than xenon. The key benefit of argon over xenon is that it produces a plume with a lower particle number-density and correspondingly a smaller back-flow of ionised propellant that may form a plasma sheath around the spacecraft and disrupt radio-frequency communications. This appealing property implies that argon may be more suitable than xenon for long missions
Ti3C2Tx MXene augments osmo-adaptive repression of the inflammatory stress response for improved wound repair
Get PDFChronic non-healing wounds represent a growing global health challenge that is poorly addressed by current advances in wound care dressings. Hyperosmotic stress linked, for example, to poor glycaemic control, is a known but under-investigated contributor to the chronic wound environment and a known inflammatory stimulus. MXene (Ti3C2Tx) has been considered for smart dressing applications but has not been investigated for use with bioactive agents to directly moderate hyperosmotic stress for improved wound care. In this study, Ti3C2Tx, in combination with osmolyte betaine, was used to investigate hyperosmotic stress-induced effects on wound closure. The effect of these materials was measured using a wound closure scratch assay, and data was used to mathematically model changes in HaCaT human keratocyte migratory rate and velocity. Changes in the upregulation of apoptotic and inflammatory markers were measured, and qualitative changes in phalloidin-labelled actin cytoskeletal structure were observed. A tert-butyl glycine betainate (tBu-GB) polyacrylate microgel loaded Ti3C2Tx dressing was then fabricated and tested for biocompatibility and slow elution of osmolyte over time. Osmotic stress at levels that did not induce cell death reduced the migratory capacity of keratocytes to close the scratch. Migration by osmotically stressed keratocytes was reduced by more than 50% at 24 h and remained at 65% (±5%) at 48 h compared to complete scratch closure at 24 h in the cell only control. This reduction was reversed by a Ti3C2Tx coating, allowing complete scratch closure by 48 h in the osmotically stressed group. Exposure of osmotically stressed cells to betaine increased normalised wound closure in the osmotically stressed keraotycte group at each time point and this was augmented by the presence of a Ti3C2Tx coating. Osmotic stress induced upregulation of inflammatory markers IL-6, IL-1α, IL-1β, CXCL1, and CXCL8 by at least 10-fold. The effect was significantly greater in the presence of bacterial LPS and this was significantly reduced by the presence of Ti3C2Tx alone and in combination with betaine. Sustained and slow release of betaine was demonstrated from a tBu-GB-microgel loaded Ti3C2Tx dressing over 48 h supporting the use of such dressings to improve osmotic stress induced, poor wound closure rates