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Oesophageal tissue engineering: optimisation of stereotactic robotic cell injection in decellularised oesophageal scaffolds
No full textPURPOSE: Oesophageal substitution following atresia repair, caustic damage or cancer of the oesophagus can be challenging. We and others are working on engineering oesophageal tissue using a combination of decellularised oesophagi and cell injection. So far this has been achieved using highly operator-dependent techniques. This study aimed to establish a reproducible method for cell delivery into scaffolds. METHODS: To improve consistency, a stereotaxic robotic platform was adapted to deliver a suspension of porcine gelatin and cells in a 1:1 ratio. The scaffold was mounted on a 3D-printed rod linked to a stepper motor, enabling automated 36° rotation for circumferential coverage. Two circumferential rows, each rotated 36°, with 3 - 2 points at 3-mm intervals, ensured even seeding. Injection depth was calibrated to target the inner layer. RESULTS: Cells injected robotically remained viable, with no significant difference from manual injection. Post-injection analyses confirmed cell viability and distribution within the scaffold. CONCLUSION: Automated robotic injection provides a reliable, reproducible alternative to manual methods, reducing operator bias
Joint Trajectory Planning and Channel Selection for AoI Minimization in Multi-UAV-Assisted IoT Networks
No full textWith the rapid popularization of Internet of Things (IoT) devices, the freshness of data has become a key factor affecting decision quality and system efficiency. The application of uncrewed aerial vehicle (UAV) technology provides a new solution for IoT data collection. This article mainly studies how multiple UAVs can improve the freshness of IoT data collection through joint optimization of trajectory planning and channel selection in a three-dimensional (3D) interference environment. We conducted markov decision process (MDP) modeling on the combinatorial optimization problem of the model and proposed an intelligent joint trajectory planning and channel selection for data collection (ITPCS-DC) algorithm based on multi-agent deep reinforcement learning (MADRL). This algorithm can not only avoid the agent falling into local optimum caused by 3D interference, but also effectively reduce the age of information (AoI) of IoT data collection. Simulation results show that the proposed ITPCS-DC algorithm can achieve higher rewards, lower average AoI, reduced channel switching costs, and shorter trajectory lengths compared to other benchmark algorithms. Moreover, it has better adaptability to more complex collaborative environments
Prospective acceptability, feasibility and outcomes of a primary school-led outdoor play intervention for young children
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Individual differences in motives for costly punishment
No full textCostly punishment is thought to be a key mechanism sustaining human cooperation. However, the motives for punitive behaviour remain unclear. Although often assumed to be motivated by a desire to convert cheats into cooperators, punishment is also consistent with other functions, such as levelling payoffs or improving one’s relative position. We used six economic games to tease apart different motives for punishment and to explore whether different punishment strategies were associated with personality variables, political ideology, and religiosity. We used representative samples from the United Kingdom and the United States (N = 2010) to estimate the frequency of different punishment strategies in the population. The most common strategy was to never punish. For people who did punish, strategy use was more consistent with egalitarian motives than behaviour-change motives. Nevertheless, different punishment strategies were also associated with personality, social preferences, political ideology, and religiosity. Self-reports of behaviour in the games suggested that people have some insight into their punishment strategy. These findings highlight the multipurpose nature of human punishment and show how the different motives underpinning punishment decisions are linked with core character traits
A multi-objective optimization strategy for ultra-low energy residential buildings based on a hybrid machine learning algorithm
No full textTo address the lack of effective multi-objective optimization approaches that balance building energy consumption, indoor thermal comfort, and life-cycle cost in ultra-low energy residential buildings, this study proposes a hybrid algorithm that integrates the Non-dominated Sorting Genetic Algorithm-II (NSGA-II) with Multi-Objective Particle Swarm Optimization (MOPSO) for the multi-objective optimization design of such buildings, validated through case studies in two climate zones. Orthogonal experiments were conducted on eight variables, including the heat transfer coefficients of external walls, roofs, and windows; directional window-to-wall ratios; and solar heat gain coefficients. An artificial neural network model for the three objectives was developed to serve as fitness functions for the hybrid algorithm. The hybrid approach outperformed the standalone NSGA-II and MOPSO in terms of the hypervolume, inverted generational distance, and spacing metrics, demonstrating superior convergence and solution diversity. Optimized design parameter ranges were derived, and best solutions were identified for both climates, providing practical guidance for similar regions. The innovations of this study include: (1) a multi-objective optimization framework balancing energy, comfort, and cost to enhance solution practicality in ultra-low energy residential buildings; (2) integration of NSGA-II-MOPSO with metamodeling for the three objectives, verified to improve optimization efficiency over individual algorithms
Motivational effectiveness of prosocial public health messaging to reduce respiratory infection risk: a systematic review and meta-analysis
No full textBackground:
Clear communication is essential for the effective uptake of public health interventions promoting protective behaviours for respiratory infection control. The emergence of novel infectious diseases, particularly the COVID-19 pandemic, has highlighted the need for rapid adaptation of established and new behavioural practices. However, there remains limited knowledge concerning effective strategies for disseminating risk-reduction information and predicting population responses.
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Methods:
This systematic review and meta-analysis (PROSPERO: CRD42020198874) assessed the effectiveness of these interventions using behavioural science frameworks, including MINDSPACE contextual influencers and behaviour change techniques (BCTs), to identify key components and mechanisms of action (MoAs). Twenty-four full-text articles, comprising 36 randomised controlled trials (RCTs) across 11 countries, were included via electronic databases (MEDLINE, EMBASE, PsycINFO, Scopus) and other sources (grey literature, Google Scholar, and reference lists) searched to March 2022.
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Results:
Here, we show that interventions mainly target social distancing, mask wearing, hand washing, and various behavioural intentions and actual behaviours, using a median of three-arm study designs with passive comparators. Interventions include a median of two contextual influencers and four BCTs. Behaviour intention is the most frequently applied mechanism of action. Study quality is moderate. Narrative synthesis of 16 full-texts (26 RCTs) shows significant effects, while network meta-analysis of 16 full-texts (21 RCTs) indicates that prosocial messages, particularly those referencing loved ones, are effective in reducing the risk of respiratory infections (d = 0.09; 95% CrI=0.06–0.14; CINeMA: Low).
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Conclusions:
Although further research is needed, the review provides insight into designing public health messages that effectively improve protective behaviours for respiratory infection control
Polymerase mutations underlie early adaptation of H5N1 influenza virus to dairy cattle and other mammals
No full textIn 2024, an unprecedented outbreak of H5N1 high pathogenicity avian influenza was detected in dairy cattle in the USA resulting in spillbacks into poultry, wild birds and other mammals including humans. Here, we present molecular and virological evidence that the cattle B3.13 genotype H5N1 viruses rapidly accumulated adaptations in polymerase genes that enabled better replication in bovine cells and tissues, as well as cells of other mammals including humans. We find evidence of several mammalian adaptations in cattle including PB2 M631L, which is found in all cattle sequences, and PA K497R, which is found in the majority. Structurally, PB2 M631L maps to the polymerase-ANP32 interface, an essential host factor for viral genome replication. We show that this mutation adapts the polymerase to better interact with bovine ANP32 proteins, particularly ANP32A, and thereby enhances virus replication in bovine mammary systems and primary human airway cultures. We show that ongoing evolution in the PB2 gene, including E627K and a convergently arising D740N substitution, further increase polymerase activity and virus replication in a range of mammalian cells. Thus, circulation of H5N1 in dairy cattle allows virus adaption improving replicative ability in cattle and poses a continued risk of zoonotic spillover
The cost-effectiveness of intraoperative margin assessment strategies during radical prostatectomy
No full textOBJECTIVE: To determine whether current intraoperative margin assessment (IOMA) techniques (such as Neurovascular Structure Adjacent Frozen-section Examination [NeuroSAFE] or confocal laser microscopy [CLM]) used during radical prostatectomy (RP) to enhance nerve-sparing surgery (NSS) while reducing positive surgical margins (PSMs) justify their extra costs, this study assessed their cost-effectiveness. METHODS: A decision analytical model assessed health outcomes and costs associated with NeuroSAFE and CLM (using the Histolog® Scanner) compared to bilateral, unilateral, and non-NSS. Outcomes were calculated in quality-adjusted life years (QALYs), with a cost-effectiveness threshold of €50 000 per QALY. NSS reduced erectile dysfunction and incontinence probabilities. However, when extraprostatic extension was present but not identified pre- or intraoperatively, NSS resulted in a PSM, increasing the risk of biochemical recurrence (BCR) and development of metastases. RESULTS: The NeuroSAFE and CLM were cost-effective strategies compared to non-IOMA strategies. NeuroSAFE was most cost-effective if NeuroSAFE and CLM were used in an equal number of patients. However, if NeuroSAFE was used in >8% fewer patients compared to CLM, CLM was most cost-effective. Sensitivity analyses highlighted the impact of PSMs on cost-effectiveness. In hospitals with higher RP volumes (>160 per year), CLM had lower costs per procedure than NeuroSAFE. CONCLUSIONS: Intraoperative margin assessment during RP is a cost-effective intervention. The choice to implement NeuroSAFE or CLM should be guided by both surgical volume and available capacity, as the more labour-intensive nature of NeuroSAFE may limit its use and reduces its cost-effectiveness compared with CLM
Investigating the relationship between taste perception of artificial sweeteners and cancer risk
No full textObjective:
To investigate whether taste perception of two artificial sweeteners—aspartame and neohesperidin dihydrochalcone (NHDC)—is causally associated with the risk of site-specific cancers.
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Design:
A two-sample Mendelian randomisation (MR) study.
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Setting:
Genetic instruments for taste perception (6 for aspartame; 13 for NHDC) were obtained from a genome-wide association study (GWAS) of Australian adolescents, and cancer outcome data were sourced from publicly available GWAS datasets.
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Participants:
Genetic data for taste perception from 1757 Australian adolescents and genetic data for cancers from large-scale GWAS cohorts, including UK Biobank (n 500 000) and FinnGen (n 500 000).
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Results:
A one SD increase in the genetically predicted perceived intensity of NHDC was associated with an increased risk of male genital cancer (OR = 1·11, 95 % CI: 1·04, 1·19) and prostate cancer (OR = 1·03, 95 % CI: 1·01, 1·08) based on FinnGen data. These associations persisted after multivariable MR adjustment for glucose and aspartame perception but were not replicated in the UK Biobank. A weak protective association between aspartame perception and cervical cancer (OR = 0·998, 95 % CI: 0·997, 0·999) was observed, but this attenuated to null in sensitivity analyses.
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Conclusions:
This study found no compelling evidence that perception of aspartame or NHDC during adolescence causally influences later-life cancer risk. The findings highlight the importance of evaluating individual artificial sweeteners separately in future research examining potential health effects