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Impact of portal vein embolisation uses in colorectal liver metastases: evidence from a rapid review
No full textObjectives To compare the short- and long-term outcomes of patients with colorectal liver metastases (CRLM) who underwent portal vein embolisation followed by liver resection (PVEfLR) with those who underwent other treatment strategies.
Design Rapid review of the literature retrieved through a systematic search.
Data sources Electronic databases PubMed, Embase and Ovid MEDLINE were searched from 1 April 2014 to 31 December 2025.
Eligibility criteria Studies were included if they involved only patients with CRLM, applied PVEfLR and reported comparative outcomes against other interventions (eg, associating liver partition and portal vein ligation for staged hepatectomy (ALPPS), liver transplantation and portal vein ligation). Only randomised controlled trials, cohort and case–control studies published in English were included. Studies that included patients other than those with CRLM were excluded.
Data extraction and synthesis Two authors independently screened records, extracted data and assessed quality using the Newcastle-Ottawa Scale. Data were narratively synthesised and presented in summary tables.
Results 14 studies (n=2,022 patients) were included. The overall median survival time for the PVEfLR group was similar to that of the ALPPS group but significantly lower than that of the liver transplantation group (19 vs 41 months, p=0.007). Postoperative complications were significantly lower for PVEfLR than for ALPPS (27% vs 65%, p<0.05) but higher than for liver resection without portal vein embolisation (51% vs 36%, p<0.001). The future liver remnant growth and completion rates for PVEfLR were variable compared with those of other techniques.
Conclusions PVEfLR is an effective strategy for converting selected patients with initially unresectable CRLM to resectable status, achieving long-term survival comparable to other complex techniques such as ALPPS, although with a different perioperative risk profile. The choice of technique should be individualised based on the patient’s anatomy, disease burden and institutional expertise
Development and Impact of Virtual Reality-Based Training for the Radial Forearm Free Flap: A Multicentre Prospective Feasibility Study
No full textIntroduction
Surgical education faces growing challenges due to reduced theatre access, variable supervision and limited procedural exposure, particularly for complex reconstructive operations such as the radial forearm free flap (RFFF). Virtual reality (VR) offers an opportunity to deliver immersive, standardised surgical training unconstrained by geography or theatre availability. This study evaluates the effectiveness of a VR-based teaching intervention in improving procedural confidence and anatomical understanding of the RFFF.
Methods
A prospective multicentre feasibility study was conducted across 10 UK medical schools and one NHS trust. Participants completed a 60-minute workshop including a 360° VR simulation of the RFFF procedure and a VR anatomical exploration session. Pre- and post-workshop surveys assessed procedural confidence, anatomical understanding and user experience using validated Likert-scale tools.
Results
141 participants completed both pre- and post-workshop assessments. The majority were undergraduate medical students (90.8%), of whom 93.8% had never previously observed an RFFF. Procedural confidence improved significantly from a median of 2 (IQR 2) to 4 (IQR 1) post-workshop (p < 0.001), with greater improvements in those without prior exposure. Anatomical confidence also increased from 3 (IQR 1) to 4 (IQR 2) (p < 0.001), particularly among pre-clinical medical students. Participants rated the module highly for educational value, immersion and clarity of anatomical and procedural content.
Conclusion
The VRiMS RFFF teaching module significantly improves learner confidence and anatomical understanding, particularly among early-stage trainees. These findings support the use of VR-based platforms as effective and scalable adjuncts to existing surgical education
Y-site compatibility studies of parenteral nutrition and other intravenous medications in neonatal and pediatric patients: a commentary.
No full textNeonates admitted to a Neonatal Intensive Care Unit (NICU) often need parenteral nutrition (PN) in combination with multiple intravenous medications. Typically, they have limited venous access points, increasing the risk of incompatibility reactions at Y-sites. These reactions, driven by physicochemical differences, can cause serious complications such as emboli and organ damage. Despite clinical importance, compatibility data specific to neonates remain limited, with most evidence derived from adult populations. This commentary critically appraises a systematic review by Gostyńska et al. (2024) (1). The review explores evidence on Y-site compatibility of PN and intravenous drugs in neonatal and pediatric patients, highlighting methodological limitations and variable study quality. The review’s authors found 56% compatibility among tested drugs, but stressed caution due to heterogeneous PN formulations and lipid emulsions impacting stability. The findings from the review should not be solely used for clinical decisions. There is a significant need for more comprehensive and systematic research to support safe clinical decision-making and reduce the risk of adverse events related to co-administration of PN and intravenous medications in neonates in NICU
AI-Powered Soil Temperature Modeling for Sustainable Agriculture in Arid Regions: A Case Study of Bustan, Uzbekistan
No full textSoil temperature is a key determinant of soil health and agricultural productivity, especially in arid regions vulnerable to climate change. This study investigates the use of advanced machine learning models to predict soil temperature variations in Bustan, Uzbekistan, a region facing significant climatic stress. Using 16 years of meteorological data, including atmospheric temperature, humidity, and wind speed, eight machine learning models were evaluated for their ability to predict surface and subsurface (10 cm depth) soil temperatures. Among the models tested, the bi-directional long short-term memory (Bi-LSTM) algorithm demonstrated superior predictive accuracy with R² values exceeding 0.94 for subsurface temperatures. The two-step modeling approach utilized Bi-LSTM outputs from surface temperature predictions to inform subsurface estimates, reflecting a novel methodology for climate-sensitive agriculture. The results provide a practical framework for improving irrigation planning, crop yield forecasting, and sustainable land management in data-scarce arid environments. By demonstrating high accuracy and real-world applicability, this AI-driven model offers a scalable solution for enhancing agricultural resilience in Uzbekistan and similar contexts
Climate Oscillations, Aerosol Variability, and Land Use Change: Assessment of Drivers of Flood Risk in Monsoon-Dependent Kerala
No full textAerosol microphysical and optical properties play a crucial role in cloud microphysics, precipitation physics, and flood formation over areas characterised by complex monsoon
regimes. This research presents a multi-source data integration approach to analyse the spatio – temporal interaction between precipitation, aerosols and flooding the state of
Kerala, incorporating air mass trajectory analysis to examine its potential contribution to flooding. Results show that Aerosol Optical Depth (AOD) values were high in the coastal
districts (>0.8) in the La Niña year (2021) but low in the El Niño year (2015). On the precipitation side, 2018 and 2021 were both years with a high degree of anomalies, resulting in heavy rainfall that led to widespread flooding in the Thrissur district, among others. Trajectory analysis revealed that the Indian Ocean controls precipitation during the southwest monsoon and the pre-monsoon. Post-monsoon precipitation is mainly sourced from the Arabian Peninsula and Arabian Sea, transferring marine aerosols along with desert aerosols. The overall study depicts that variability in aerosol and precipitation is more subject to change by the meteorological dynamics, as well as influenced by the regional changes in land use and land cover, causing fluxes in the land-atmosphere interactions. In conclusion, the present study highlights the possible interactive functions of atmospheric dynamics and anthropogenic land use modifications in generating flood hazard. It provides essential information for land management policies and disaster risk reduction
Contribution of Lumbricus terrestris enhancement to soil fertility and maize and wheat yields in soil tillage systems
No full textEarthworms provide important ecosystem services such as plant yield increase and soil structure improvement. Soil tillage systems affect earthworm abundance, e.g., that of Lumbricus terrestris, the burrows of which can increase water infiltration. We tested the impact and mechanisms of additional L. terrestris on plant growth and soil physical parameters in Austria. At two sites, 14 individuals m−2 were inoculated under different soil tillage systems into large enclosures of 7.5 m2, to compare enhanced versus ambient numbers of L. terrestris for maize (Zea mays) followed by wheat (Triticum aestivum). Tested soil tillage systems were plough (CON, 30 cm depth), cultivator (RED; 15 cm depth) and no soil tillage (NT; 0 cm depth). The success rate of inoculation was similar between the soil tillage systems at 33–44 %. Number of middens were increased for enhancement than control and was highest for NT than RED and CON. At level enhancement, grain yield and N grain yield of maize were increased by 10; 13 % and 17; 23 % respectively for CON and RED, while wheat was unaffected, due to insufficient precipitation. At flowering of maize, topsoil moisture at site 2 was 18 % and 17 % higher for enhancement than control for CON and RED, while NT and wheat were unaffected. Soil aggregate stability was 2.7–2.9 times more stable at level enhancement than control for CON and RED for maize, respectively. It was shown that earthworms contribute to plant growth and soil fertility within a relatively short period. Increased numbers of earthworms had the highest effect on plants and soil parameters for CON and RED, which are usually considered to have a weaker soil structure than NT. Earthworms can therefore facilitate the conversion from CON and RED to NT for climate change adaptation and can improve soil fertility
A Multi-Level Meta-Analysis of Vagally-Mediated Heart Rate Variability and Post-Traumatic Stress Disorder
No full textPosttraumatic stress disorder (PTSD) is frequently associated with autonomic nervous system (ANS) dysregulation, as evidenced by diminished vagally mediated heart rate variability (vmHRV). To date, no meta-analysis has systematically compared 5-minute and 24-hour vmHRV recordings in PTSD, limiting our understanding of how recording duration influences findings. This study examined differences in vmHRV between individuals with PTSD and controls using both 5-minute and 24-hour recordings. The meta-analysis synthesised data from 24 studies involving 2,477 participants and 34 effect sizes. A novel analytical approach was used and involved traditional multi-level meta-analysis, robust variance estimation, and separate analyses across vmHRV indices and recording durations to isolate independent effects. Whilst vmHRV was consistently reduced in individuals with PTSD, the magnitude of this effect was greater in studies utilising 5-minute recordings than those using 24-hour recordings. Therefore, the results indicate that methodological differences in HRV assessment, particularly recording duration, significantly influence the observed magnitude of vmHRV reductions in PTSD. The robust analytical strategy enhances the reliability of vmHRV as a biomarker of ANS dysregulation in PTSD. The findings highlight the need for standardised vmHRV protocols in PTSD research
The Development of a VR Wireless Signal Propagation Simulator in Unreal Engine: A Device and Performance Testing
No full textThe wireless communication industry and research community focused on developing accurate and efficient models for signal propagation extensively over the past years. High-fidelity simulation software often comes with high costs and relies heavily on offline computations, limiting flexibility and scalability. This paper introduces a low-cost prototype for simulating signal propagation, leveraging advancements in Gaming technologies, Virtual Reality, and Digital Twins. The system is capable of conducting ray tracing simulations of wireless signal propagation through various configurable parameters and fidelity levels, generating signal strength heat-map and real-time ray visualization in immersive VR and 3D desktop modes. Thorough device and performance testing validated the prototype’s development and assessed implementation feasibility. The findings establish its operational capabilities and performance metrics, providing insights and guiding further development and refinements, ensuring its reliability and effectiveness in simulating complex wireless propagation
Spiral arms across stellar populations in simulations via the local dimension method
No full textContext. The origin and nature of spiral arms remain unclear. Star forming regions and young stars are generally strongly associated to the spiral structure, but there are few quantitative predictions from simulations about the involvement of stars of different ages. Aims. We aim to quantify the interplay between spiral arms and different populations. Methods. We use a hydrodynamical simulation of an isolated disc galaxy displaying a dynamic multi-armed spiral structure. Inspired by cosmological structure metrics, we develop a new method, the local dimension, that robustly delineates arms across populations and through space and time. Results. We find that all stars, including those as old as 11Gyr, support the arms. The spiral strength decreases with stellar age up to 2Gyr-old stars and remains nearly constant for older stars. However, the scaling between arm strength and age (or velocity dispersion) depends on the strength of the global spiral structure at each time. Almost all stars formed in arms remain within them for no more than 140-180Myr, whereas old stars leave arms about three times faster. Even if the youngest populations dominate in the production of the spiral torques at early times, all populations contribute equally at later times. Conclusions. Our results highlight the power of the local dimension for studying complex spiral structures and show that all stellar populations in the disc partake in the arms. Since in our model we see spiral arms in populations with velocity dispersions up to 90km/s, which are comparable to those of the Milky Way, we predict that old Galactic populations could also exhibit spiral structure
Tolerating the turn: Can an alternative pillow solution offer better pressure redistribution during prone positioning?
No full textObjective:
Effective pressure management and comfort during prone positioning are core to improved ergonomics and patient tolerance, minimising the need for enhanced respiratory support techniques, such as mechanical ventilation. This study explored the impact of a new (low-tech) pillow solution on interface pressure and comfort during prone positioning compared with standard hospital solutions.
Method:
In this healthy patient cohort, within-subject, comparative study, person–surface interface pressures were measured for three different conscious prone positioning conditions: a standard hospital pillow at the head (HPO); a three-pillow standard hospital proning solution (HPP); and a new two-pillow prone positioning solution with additional standard head pillow (LPP). Contact surface area, peak and mean pressure, peak pressure index (PPI) (head, trunk, pelvis, legs), and subjective comfort were calculated for all conditions over a 21-minute period.
Results:
The study cohort comprised 20 healthy volunteers. The LPP solution lowered PPI at the trunk compared to HPP (p<0.017) and HPO (p<0.001). The LPP solution also significantly reduced head PPI compared to lying with only a head support (p<0.002). Both HPP and LPP significantly improved comfort compared to proning with a head support only (both p<0.002).
Conclusion:
Overall, improved pressure management and comfort was noted for the alternative prone positioning kit, compared with existing solutions, suggesting a low-tech alternative to improving tolerance and adherence of patient prone positioning