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On the border: searching for cometary activity near the Centaur–JFC Transition Line
No full textCurrent wide-field surveys discover ∼15 Jupiter-family comets (JFCs) each year, typically identified via visual detection of a dust coma or tail. The same surveys also discover many asteroids that have distant JFC-like orbits, but with no reported activity. We observed asteroids on Jupiter-crossing orbits beyond the depth of typical survey imaging using the 2.5 m Isaac Newton Telescope. We used deep imaging to observe 16 asteroids in this region, plus seven known comets for comparison. Three asteroids (2011 WM183, (669525) 2012 XO144, and 2020 RX133) showed surface brightness profiles consistent with low-level activity, equating to ∼19% of our total sample. We note that 2020 RX133 is a Jupiter Trojan. When we considered the heliocentric distance range of the asteroids at the time when they showed activity, this fraction increased to 33% of the targets in the 3.16 au ≤ Rh ≤ 4.56 au region, and therefore it is possible to infer that at least ∼30 asteroids with TJ ≤ 3.05 and in the 4.05 au < a < 5.05 au parameter space may potentially exhibit low-level activity. We also estimated nuclear radii for the three active targets of rn = 1.8 ± 0.2 km, rn ≤ 0.8 km, and rn ≤ 0.5 km for (669525) 2012 XO144, 2011 WM183, and 2020 RX133, respectively. The median color index for the observed asteroids is (g − r)PS1 = 0.52 ± 0.13, aligning with those expected for D-type asteroids
Enhancing lactation performance and energy utilisation efficiency through dietary inclusion of apple pomace silage and hempseed cake in dairy cows
No full textApple pomace (AP) and hempseed cake (HC) are used for replacing conventional feed ingredients in dairy farming, but their effects on energy partitioning remains insufficiently explored. This study investigated the effects of dietary inclusion of AP silage and HC to mid-lactation dairy cows on lactation performance and energy utilisation efficiency. Fifteen dairy cows were used in a 3 (treatments) x 3 (Periods) Latin square design study. Treatment diets included (dry matter [DM] basis) (1) CON: basal diet containing 50.0% concentrates, 45.7% grass silage and 4.3% barley straw; (2) AP: 10% of AP replaced grass silage in the CON diet; (3) HC: 10% of HC replaced concentrates in the CON diet. Dietary inclusion of AP or HC significantly increased DM intake (DMI) by 6.7% and 3.4% (P = 0.001), milk yield by 8.8% and 11.3% (P < 0.001), compared with CON. Milk yield per unit of DMI was the highest in HC, followed by AP and CON (P =0.022). Crude protein digestibility was higher in AP than in CON group (P= 0.038). When compared with CON, both AP and HC tended to increase rumen propionate production (P = 0.082) and significantly decreased rumen acetate: propionate ratio (P= 0.040). Urinary and methane energy outputs and heat production as a proportion of gross energy intake (GEI) significantly decreased when diets were supplemented with AP and HC (P < 0.01), and inclusion of AP also increased retained energy as a proportion of GEI. Feeding AP and HC significantly decreased heat production/metabolisable energy (ME) intake by 10.7% and 7.6% respectively (P < 0.001). Higher efficiency of ME used for lactation was observed in AP and HC group, increasing by 4.3% and 7.7% respectively (P = 0.017), compared to CON. Overall, AP silage and HC are promising alternatives to high-quality grass silage and conventional protein feeds in dairy cow diets. These by-products can enhance the lactation performance and improve cow’s energy utilisation efficiency
A comprehensive review of nano-enhanced phase change materials for electric vehicle and power electronics thermal management
No full textNano-enhanced phase change materials (NEPCMs) are a novel small-scale passive technique for thermal management in electric-cars and high-power electronics. This paper summarises the innovations in materials, mechanistic-insights, and system-level performance of NEPCMs and quantifies reported advances to guide engineering execution. Nano-additives based on carbon, including graphene (40%–120%), carbon nanotubes (25%–80%), metal-oxide fillers (20%–60%) and MXenes (60%–150%), enable significant increases in thermal-conductivity, dependent on loading and dispersion-quality. The scalable-processing and low-temperature carbon-additive routes can reduce material-costs by 20%–35% compared to early laboratory-formulations and can thus match active cooling in cost-performance at moderate heat-fluxes. Performance enhancement approaches, such as hybrid PCMs, thermo-responsive and multi-functional PCMs, and their application in practical scenarios, especially in EV battery thermal control, power-electronics cooling and rapid charging are addressed. It also discusses the major issues of NEPCM implementation, including dispersion-stability, thermal-degradation and nanotoxicity, and suggests future research directions to mitigate these shortcomings.<br/
The social life of non-parents: A systematic review of social networks and social support among adults without children
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Developing and calibrating a colorectal cancer microsimulation model for Northern Ireland
No full textBackgroundIndividual-level microsimulation models are essential for evaluating colorectal cancer (CRC) screening programmes to capture the heterogeneity in disease progression. To ensure regional relevance, such models require detailed natural history structures and robust calibration to population-specific data. This study presents the development of the first CRC natural history microsimulation model tailored to Northern Ireland (NI) for evaluating the NI Bowel Cancer Screening Programme (NI BCSP).MethodThe model simulates individual trajectories from adenoma onset to CRC diagnosis. Eight natural history parameters were calibrated to sex-specific CRC incidence data, initially using empirical (frequentist) calibration and Approximate Bayesian Computation (ABC) rejection, followed by the ABC-Markov Chain Monte Carlo (ABC-MCMC) algorithm. Other parameters were informed by NI-specific data sources.ResultsThe frequentist and ABC rejection calibration approach’s posterior distributions informed the prior distribution for the ABC-MCMC approach. ABC-MCMC was informative, yielding 55 parameter sets, but results were constrained by limited calibration targets and parameter identifiability.ConclusionThis is the first NI-specific CRC microsimulation model, providing a regionally tailored platform for evaluating screening strategies and supporting policy. Calibration was feasible in a data-limited context, but further refinement and additional targets are needed to improve parameter estimation
Photon FLASH spares radiation-induced changes in cardiac function, remodelling and arrythmia in a preclinical model
No full textIntroductionPreclinical studies have demonstrated the ability of FLASH irradiation to expand the therapeutic window by sparing normal tissues. The heart is a critical organ at risk in patients receiving radiotherapy for thoracic cancers. This study aimed to quantify the cardiac sparing effects of photon FLASH delivered as single (FLASH) or FLASH split dose (FSD) exposures.MethodsFemale C57BL/6 mice were irradiated with 18.5 ± 0.6 Gy delivered to the whole heart using a FLASH-SARRP (Xstrahl Life Sciences, UK) at a dose rate of 85.6 ± 1.6 Gy/s (isocentre dose rate 75.9 ± 1.5 Gy/s). Comparative studies were undertaken using 18.6 ± 0.4 Gy delivered using two consecutive pulses (FSD) at an average dose rate of 2.8 ± 0.9 Gy/s, and with 20.1 ± 0.5 Gy using a conventional SARRP at a dose rate of 3.4 ± 0.2 Gy/min (CONV). Transthoracic echocardiography was performed at 10 and 30 weeks with supporting histology and analysis of serum biomarkers 30 weeks post irradiation.ResultsIn comparison to CONV and FSD exposures, FLASH significantly reduced radiation-induced loss of cardiac function, cardiac remodelling and arrythmia 30 weeks after irradiation. These observations were supported by reduced myocardial fibrosis, cardiac injury biomarkers and inflammatory cytokines.ConclusionsThis study highlights the ability of photon FLASH to preserve cardiac function and structure from radiation damage with the level of sparing dependent on average dose rate and beam structure.<br/
The impact of periodontitis on oral health outcomes in older adults: a systematic review
No full textObjective: To systematically review the impact of periodontitis on clinical oral health outcomes and oral health‐related quality of life (OHRQoL) in older adults (≥ 60 years).Background: Global evidence shows that severe periodontitis prevalence peaks in the 60s, yet how periodontitis relates specifically to oral health outcomes in older adults has not been comprehensively synthesised. Prior reviews in mixed‐age populations demonstrate strong links with tooth loss but less consistent associations with OHRQoL. Methods: This systematic review followed PRISMA guidelines and was registered on PROSPERO (CRD420251010568). Searches of PubMed, MEDLINE, Embase, Scopus, and Cochrane Library (to May 2025) identified studies of adults ≥ 60 years with periodontitis reporting oral health outcomes or OHRQoL. Two reviewers independently screened studies, extracted data, and assessed risk of bias. Results: Forty‐three studies met inclusion criteria: 18 longitudinal studies on clinical outcomes and 25 cross‐sectional studies on OHRQoL. Clinical studies consistently demonstrated that deeper baseline periodontal pockets, greater clinical attachment loss, and higher CPI/CPITN scores predicted adverse outcomes over 18 months to 12 years follow‐up, including tooth loss, further attachment loss, and functional decline. OHRQoL studies showed inconsistent findings, with roughly equal numbers reporting significant associations versus no relationship. Conclusions: In adults ≥ 60 years, periodontitis consistently predicts tooth loss and continued periodontal breakdown, whereas OHRQoL associations are inconsistent and appear mediated primarily through downstream consequences such as tooth loss and functional impairment, though direct effects may occur in advanced disease. These findings emphasise the importance of periodontal prevention and management in older adults
Design of flexible DC-SOP toward four-quadrant power flow control in bipolar distribution networks
No full textThis letter introduces the direct current soft open point (DC-SOP), which is a bipolar DC-DC converter designed to achieve independent four-quadrant power flow control in bipolar DC distribution networks (BDDNs). For the first time, asymmetric dual active bridges are employed to connect the four-quadrant ports, ensuring a flexible power channel to realize flexible power transfer between branches and poles. Bidirectional shift modulation strategy and four-quadrant decoupling facilitate independent power control, effectively mitigating branch overload and inter-pole power unbalance. To improve model linearization accuracy, a refined relaxation method is proposed, providing theoretical guidance for DC-SOP applications in BDDNs. The effectiveness of the proposed method is validated in ±10kV BDDNs with 33 nodes and 123 nodes
Development of entrustable professional activities for competency-based prosthodontic specialty training programmes
No full textOBJECTIVES: This study aimed to develop and validate a set of Entrustable Professional Activities (EPAs) for prosthodontics specialty training using a structured multi-step approach.METHODS: An initial list of EPAs was generated through a comprehensive literature review, examination of prosthodontics competency standards, and an asynchronous online nominal group technique involving national prosthodontists and a dental education expert. This process was used to develop and confirm the EPA set. The EPAs were then evaluated for quality and structure using the Equal rubric, resulting in the refinement and confirmation of relevant EPAs. Subsequently, a two-round modified Delphi method was employed, engaging prosthodontics educators from multiple countries in a consensus-building process. In the modified Delphi rounds, panellists reviewed a predefined list of EPAs and provided quantitative ratings and qualitative comments on indispensability (Round 1-2), title clarity (Round 1-2), specification/limitations (Round 1-2), information supporting entrustment decisions (Round 2), and expected entrustment level at each stage of training (Round 2). Based on median ratings and content validity index analysis the EPAs were revised accordingly. Aggregated scores for each EPA and synthesised group feedback for consensus development were provided in Round 2.RESULTS: The expert group confirmed 11 of the 20 initially identified EPAs. All 11 preliminary EPAs reflected activities that were deemed essential to the clinical practice of prosthodontists. Based on median ratings and content validity index analysis, 8 EPAs needed revision. A high degree of consensus among experts was reached in the second Delphi round. The final set of 11 EPAs provide a succinct and comprehensive overview of the core tasks of specialist prosthodontists.CONCLUSION: This study developed 11 EPAs for prosthodontics specialty training programmes, representing an essential first step toward developing a structured assessment system for prosthodontic trainees.CLINICAL SIGNIFICANCE: This study provides a further step towards competency-based specialty training in prosthodontics.</p