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Research training in radiation oncology: a scoping review of global pathways, barriers and enablers
Get PDFBackground
There is a disparity between the importance of radiation oncology (RO) to cancer care and the research activity that underpins it. This may relate to inadequate availability of, or barriers within, residency research training. This scoping review sought to characterize the barriers and enablers to RO research training, and to summarize relevant training pathways.
Methods
Systematic Medline and Embase searches were conducted using “RO”, “research”, “training”, and related terms, to identify reports published between 2010 and 2025. Manuscripts were screened using predefined inclusion and exclusion criteria to select those describing research initiatives, and barriers and enablers to resident-level research. These features were extracted along with country of origin and study design parameters.
Results
Of 1745 identified manuscripts, 54 were included. Most reports originated from North America (n = 24/54; 44.4 %), Europe (n = 12/54; 22.2 %) and Australasia (n = 8/54; 14.8 %). A majority were survey-based studies (n = 27/54; 50.0 %) or observational cohort analyses (n = 10/54; 18.5 %). We identified seven countries with mandated resident-level research training and three regions/countries with RO-specific physician scientist training programs. These varied from integrated training schemes that include higher research degree completion, to short-interval initiatives. Five programs were supported by metrics detailing their impact. Reported enablers and barriers demonstrated a subtle geographic variation but included protected time and funding, mentorship and attainment of research skills.
Conclusion
There is global variation in research training during RO residency but numerous shared enablers and barriers. These data provide shared best practice and a scaffold on which national and international societies can build improved research training pathways to redress the radiation research deficit
Effects of grain size on landslide–forest interaction
No full textForests play an essential but poorly-understood role in mitigating landslide runout by providing mechanical resistance and dissipating flow energy. Despite growing interest, existing models treat forests as friction modifiers or generic porous obstacles, and largely ignore how grain size controls retention and jamming. This study experimentally investigates and resolves the influence of grain size, slope angle, and tree spacing on landslide–forest interactions using reduced-scale flume tests with different granular materials. Results show that although forests can reduce flow mobility, preferential flow paths may develop along trees, leading to ineffective energy dissipation along the flow flanks. For fine-grained flows composed of sand, the deposition behaviour is governed by the normalised slope angle and the transverse blockage ratio. For coarse-grained flows composed of gravel, the deposition and retention are controlled by two distinct jamming mechanisms: frontal deposit-induced jamming and arching-induced jamming. Frontal deposit-induced jamming occurs in all jamming cases, whereas arching-induced jamming only develops when tree spacing is smaller than three times of the grain size. We capture this variety of phenomena within two phase diagrams for fine-grained and coarse-grained flows. The phase diagrams provide a direct screening rule for minimum tree density and slope condition required to ensure jamming for a given grain size distribution
Forgotten fibre waste: Mycoremediation and recycling of used absorbent hygiene products
No full textBeyond clothing, end-of-life technical textiles and nonwoven products are an additional source of fibre-based waste and environmental impact. Absorbent Hygiene Products (AHPs), i.e. single use, disposable diapers (nappies), adult incontinence and menstrual products, play an important role in supporting the personal hygiene and wellbeing of millions of people worldwide, but their disposal presents considerable waste management and environmental challenges due to their biological contamination, as well as mixed fibre and polymer composition. Despite high rates of consumption, used AHPs remain one of the hardest waste streams to recycle, and most are incinerated or landfilled. Internationally, very little used AHP recycling infrastructure exists, and generating high-value outputs from such waste is highly challenging, mainly due to its multifaceted nature. This review evaluates the potential for an alternative biotechnological approach to recycling based on mycoremediation and biocatalysis of used AHPs (containing cellulose, superabsorbent polymers and synthetic polymers) harnessing fungi to valorise the cellulosic and plastic components of the waste. We focus on the synergistic integration of mycoremediation and precision fermentation techniques as part of a biorefinery model to yield valuable material outputs from used AHPs, such as industrial chemicals and fibre-forming biodegradable polymers for industrial applications, as a basis for new circular economies
Testing Volcano Deformation Models Against 3D Seismic Reflection Imagery of Ancient Intrusions
Get PDFMagma intrusion often drives uplift of the overburden and free surface. Analytical modeling of such surface uplift at active volcanoes allows us to estimate intrusion geometries and positions, as well as volume and pressure changes; these insights have proven critical to forecasting volcanic unrest and eruptions. However, it is rarely possible to compare geodetic source parameters retrieved from analytical models to known intrusion geometries. Seismic reflection data offer an opportunity to image and quantify ancient, buried intrusion geometries and their overburden deformation (i.e., a forced fold). Here, we use 3D seismic reflection data offshore NW Australia to investigate an Early Cretaceous forced fold developed above a laccolith emplaced at ∼0.6–1 km depth. We remove the effects of post-emplacement, burial-related compaction and estimate surface displacement patterns for the forced fold. Analytical modeling of these surface displacements, using both thin plate bending and elastic half-space solutions, suggest source (intrusion) estimates of position and lateral dimensions are similar to those of the actual laccolith. There are some differences between measurements of the laccolith and modeled source estimates, which we attribute to syn-intrusion space-making mechanisms (e.g., compaction). We particularly find penny shaped crack and rectangular dislocation elastic half-space solutions underestimate source emplacement depth by ∼0.2–0.9 km, probably reflecting a lack of heterogeneity (layering) in our models. Our novel approach highlights seismic reflection data is a powerful tool for understanding and testing how magma emplacement translates into surface deformation at active volcanoes
Benefit–risk of colchicine and spironolactone in acute myocardial infarction: a prespecified generalised pairwise comparisons analysis of the CLEAR trial
Get PDFBackground: Composite outcomes in cardiovascular trials often group events of unequal clinical importance, and conventional analyses may obscure treatment trade-offs. Generalised pairwise comparisons (GPC), expressed as a win ratio (WR), allow for hierarchical ranking of events and incorporation of recurrent outcomes, providing a potentially more intuitive assessment of benefit-risk.
Methods: In a prespecified exploratory analysis of the 2×2 factorial, randomised CLEAR (Colchicine and Spironolactone in Patients with Myocardial Infarction) trial (7062 patients within 72 hours of acute myocardial infarction (MI) and percutaneous coronary intervention), we applied both time-to-first and recurrent-event GPC to reassess low-dose colchicine (0.5 mg daily) and spironolactone (25 mg daily) versus placebo. For the colchicine comparison, the hierarchical benefit-risk outcome included all-cause death, stroke, recurrent MI, unplanned ischaemia-driven revascularisation, serious infection or diarrhoea. For the spironolactone comparison, the outcome included all-cause death, stroke, MI, new or worsening heart failure, significant ventricular arrhythmia, hyperkalaemia or gynaecomastia/gynaecodynia. GPC results were compared with Cox, logistic and Andersen-Gill models.
Results: For colchicine, the time-to-first event GPC showed a 12% lower proportional win rate compared with placebo (WR 0.88, 95% CI 0.79 to 0.98; win difference -2.10%, 95% CI -3.84 to -0.37), driven largely by excess diarrhoea. For spironolactone, patients experienced a 14% lower win rate (WR 0.86, 95% CI 0.75 to 0.99; win difference -1.46%, 95% CI -2.84% to -0.08%), largely attributable to gynaecomastia and hyperkalaemia. Conventional statistical approaches yielded concordant results. Across both interventions, higher-order efficacy outcomes (death, MI, stroke, heart failure) showed no benefit.
Conclusions: In patients with post-MI, both low-dose colchicine and spironolactone demonstrated disadvantageous benefit-risk profiles, reinforcing that neither agent should be used routinely. This prespecified application of GPC provided results consistent with traditional methods but offered a clinically intuitive framework for interpreting composite outcomes
A steady-state model for tilting pad journal bearings incorporating an analytical extension of the Sommerfeld solution
Get PDFAn analytical model for a tilting pad journal bearing has been developed by adapting a correction factor method previously used for standard journal bearings. The approach derives the Sommerfeld solution for an infinitely long tilting pad bearing and uses it to adjust the centerline pressure of an infinitely short bearing. This semi-analytical solution addresses a gap in the literature on finite-length tilting pad bearings. Analytical models offer valuable insights into variable interactions and enable faster computation, useful in systems with fluctuating loads, like energy transmission systems. Validation across varying journal speeds and load directions showed a maximum error of 23.5% on the most loaded pad, demonstrating the model’s usefulness in early-stage design, mapping operational envelopes, and assessing bearing suitability
Multiaxial notch fatigue of corroded cast iron pipes
Get PDFGrey Cast Iron (GCI) water pipes often develop localised corrosion pits that act as notches and can also experience biaxial fatigue stresses, resulting in a multiaxial notch fatigue problem. This paper experimentally investigates for the first time, the high-cycle fatigue sensitivity of GCI to localised notches, under bending and biaxal loading, and validates a multiaxial notch fatigue model for GCI. The work uses a recently developed, novel biaxial fatigue experiment to generate the first fatigue data for GCI featuring pit-like notches. Approximately 40 new fatigue tests were completed to calibrate and test four multiaxial notch fatigue models, and to investigate the effects of notch root radius, localised notches, bending loading, and biaxial loading. The data shows that pit-like notches can have a statistically significant influence on the fatigue strength of GCI when Kt,n > 4. Additionally, 180° out-of-phase biaxial loading was found to reduce the fatigue strength of un-notched specimens by 28 %. The Effective Volume notch fatigue model, coupled with the linear-elastic Smith-Watson-Topper criterion, was found to give good predictions for notched GCI pipes subject to uniaxial and bending loading. This work highlights the ability of the Effective Volume approach to make good fatigue life estimates for thin, notched components featuring inclusions, where critical distance-based approaches performed less well. Future work on similar problems may wish to consider this approach
Flame impingement to facilitate the stability of NH3-CH4 laminar diffusion flames: High-speed imaging and schlieren visualization
No full textAs a hydrogen-rich and carbon-free fuel with high energy density, ammonia is regarded as a promising substitute for fossil fuels. In this study, flame characteristics and flow field were investigated to explore the maximum substitution ratio of ammonia (critical substitution ratio, i.e.) in NH3-CH4 by high-speed direct imaging and schlieren method. To follow up the realistic scenario of flames in enclosed combustion systems, the stability of impinging flame was also investigated under the effect of water-cooled copper wall. The results showed that the critical ammonia substitution ratio for free laminar flames was less than 63 % for the tested cases. Meanwhile, the free flames exhibited periodic expansion and separation, with significant fluctuations in lift-off height and flame stretch rate, accompanying with the periodic motion of the shear layer between the flame and air. After the introduction of the impinging wall, the critical ammonia substitution ratio of the flame increased from 63 % to over 80 % (up to 94 %) in dependent upon the height of impinging wall. At low ammonia substitution ratio (40 %), reducing the impingement height enhanced the stability of the flow field by suppressing the development of shear layers and vortex around the flame. When the ammonia substitution ratio gradually increased to 63% and the critical substitution ratio, the flame anchored on the wall at different impingement heights, and no obvious vortex development was observed in the flow field. Higher ammonia substitution ratios can weaken the influence of impingement height on the flame flow field
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