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Understanding forest wind damage during mountain wave events: Insights from a case study in Norway
No full textForest wind damage models are typically based on the assumption that windstorm damage results from the interaction between horizontal wind forces and forest stand properties. In complex terrain, mountain waves caused by stably stratified air flowing over mountains can generate standing waves and severe downslope windstorms on the leeward side. Using the windstorm of 19 November 2021 in a mountain valley in southeastern Norway as a case study, we tested two hypotheses:1. Forest stand properties do not significantly contribute to explaining forest damage during a mountain wave event.2. Meteorological variables related to atmospheric stratification, turbulence, and non-horizontal airflow significantly contribute to explaining forest damage during a mountain wave event.To test these hypotheses, we combined forest damage observations with a high-resolution numerical weather prediction model and Random Forest modeling. We used SHapley Additive exPlanations (SHAP) values to quantify the contributions of individual model features. Incorporating forest stand variables did not significantly improve predictive performance, whereas potential temperature gradient, vertical airflow velocity, and wind gust speed, capturing turbulence, did. SHAP analysis showed that although wind gust speed helped explain damage, its influence was secondary to that of potential temperature gradient, which had the strongest explanatory power. The model demonstrated good discriminative power between damage and no damage in the test set. Our findings underscore the limitations of conventional models reliant on horizontal wind speed, highlighting the need for high-resolution numerical weather prediction models that resolve three-dimensional flow in complex terrain, especially during mountain wave events
Assessing farmers' willingness to sell straw for energy and material applications in Sweden
No full textThis study examines farmers' willingness to sell straw for energy and material applications in Scania, Sweden. Using interviews and surveys, we tested three empirical consequences derived from the premise that missing data on farmers' willingness to sell straw for energy may misrepresent the biomass supply in potential assessments. Findings reveal willingness to sell straw depends on end use, with farmers preferring benefits like manure in barter arrangements over bioenergy. Land tenure is key; those leasing over 50 % of their land are more likely to be willing to sell. Contrary to expectations, straw supply is not highly price-sensitive; competing uses like animal bedding influence decisions. Up to 57 % (95 % CI: 42–75) of cereal and oilseed land could be made available for energy, though agronomic and competing use limit this potential. These results challenge viewing straw as a residue and highlight the need for region-specific policies reflecting land tenure, local practices, and agronomic priorities. Integrating nutrient recycling, diversified straw uses, and agroecosystem planning could enhance biomass availability and agricultural sustainability. Further research should assess effectiveness, including carbon farming regulations. This study offers insights for aligning bioenergy goals with agricultural sustainability in biomass policy
Safety and equity in scaling minimally invasive surgery worldwide in 109 countries using cholecystectomy as a tracer procedure : a prospective cohort study
No full textBACKGROUND: Minimally invasive surgery is rapidly expanding globally, yet there is insufficient knowledge of how to scale this technology safely and equitably across diverse health systems. We aimed to identify health-system factors associated with safe implementation of minimally invasive surgery globally, using minimally invasive cholecystectomy as a tracer procedure.METHODS: We conducted a multicentre, prospective cohort study of consecutive adults undergoing cholecystectomy between July 31 and Nov 19, 2023, in 1218 hospitals across 109 countries. Data were collected by more than 10 000 health-care workers using a core measurement set mapped to the WHO Health System Building Blocks and the Global Patient Safety Action Plan. The primary outcome was 30-day procedure-specific complications, with multilevel logistic regression used to examine associations between health-system features and patient outcomes. This study is registered on ClinicalTrials.gov (NCT06223061).FINDINGS: Among 52 187 included patients, the adjusted procedure-specific complication rate varied 40-fold between hospitals, from 0·3% in the lowest risk quintile to 12·1% in the highest risk quintile. Despite large structural differences across income groups in access to minimally invasive surgery, diagnostics, and emergency services, country income level was not independently associated with complication rates (adjusted odds ratio [OR] 0·81 [95% CI 0·59-1·10] for upper-middle income vs high income and 0·99 [0·70-1·39] for lower-middle income or low income vs high income). Three modifiable hospital-level factors were strongly associated with safer outcomes: establishment of local simulation-based training facilities (adjusted OR 0·78 [0·71-0·86]; p<0·0001), adoption of intraoperative safety and communication strategies (0·87 [0·79-0·96]; p=0·0046), and on-site CT diagnostics (0·79 [0·65-0·97]; p=0·0220). Training facilities showed the greatest benefit in hospitals with limited infrastructure and an inexperienced workforce: the number needed to treat to prevent a procedure-specific complication was 21 (95% CI 14-35; p<0·0001).INTERPRETATION: Safe implementation of minimally invasive surgery varies widely worldwide but is not defined by national income level; differences in outcomes reflect the ability of health systems to adopt and safely deploy new surgical techniques. We identified for the first time that the presence of local simulation-based training facilities is independently associated with improved patient outcomes. Simulation appears to be fundamental to the safe delivery of minimally invasive surgery, particularly in resource-constrained settings. Together with safety systems and diagnostic capacity, these findings offer actionable targets for health systems seeking to equitably scale up essential surgical technologies.FUNDING: NIHR Global Health Research Unit and Wellcome Leap SAVE Programme
Mid-Term Outcomes of PTFE-Based Contralateral Iliac Limbs in Polyester-Based Fenestrated Bifurcated Endografts
No full textPurpose: The aim of this study was to evaluate the feasibility and mid-term results of combining polytetrafluoroethylene (PTFE)-based iliac limbs, having a short dilator tip, with a polyester (Dacron)-based bifurcated component during a fenestrated endovascular aortic repair (FEVAR).Materials and methods: All patients who underwent a FEVAR procedure in a single tertiary center were screened for inclusion in the study. Data were collected retrospectively and all imaging was reviewed for the study. The criterion for inclusion in the study was the implantation of a PTFE-based iliac limb endoprosthesis at the contralateral side of the polyester-based bifurcated component during a FEVAR procedure landing in a native common iliac artery. The primary study endpoints were technical success, adverse events, and reinterventions related to limbs, migration between contralateral iliac limbs and bifurcated components, type Ib and IIIa endoleaks, and iliac limb patency.Results: A total of 30 patients with a median age of 77 (70, 79) years, who underwent FEVAR procedures from June 2020 to July 2023, were included in the study. The total number of target vessels was 116, and the majority (N = 24) of patients received 4 fenestrations. Technical success was achieved for the iliac limb in all patients, and for the FEVAR, it was obtained in 29 cases (97%). Median follow-up was 24 (12, 30) months. There were no clinical limb-related adverse events or reinterventions. At the end of the follow-up period, all limbs remained patent. The median absolute and percentual change in overlap between the limb and the cuff of the bifurcated endograft was of -0.1 mm (-0.8, 1.1) and -0.4% (-2.7, 4), respectively. The estimated primary, secondary clinical success of the FEVAR, and survival rates (± standard error) at 2 years were 86 ±7%, 90±6, and 83±7%, respectively.Conclusions: The present study demonstrated promising mid-term outcomes, with the absence of limb-related adverse events, reinterventions, and any significant change in the overlap of PTFE iliac limbs combined with polyester bifurcated device during FEVAR. Further validation in a larger cohort as well as comparative analysis between different component combinations are needed to confirm the findings of the present study.Clinical ImpactThis study underscores the feasibility and excellent mid-term clinical outcomes of combining PTFE-based iliac limbs with a short dilator tip and a polyester-based bifurcated component during fenestrated endovascular aortic repair. The absence of significant migration and adverse effects related to the iliac limbs, along with the lack of target vessel occlusions, suggests a potential advantage of using a delivery system that avoids crossing the fenestrations, thereby enhancing technical success and ensuring stable and durable results over time
Modelling wildfire and post-fire carbon budgets of a boreal forest under a changing climate
No full textUnderstanding the dynamics of post-fire carbon recovery is critical for managing boreal forests under climate change. This study evaluates the LPJ-GUESS-BLAZE models’ performance in simulating vegetation structure, fire emissions, and post-fire carbon dynamics at the stand scale in a boreal forest in Sweden. Combining current climate and future scenarios (SSP1–2.6, SSP5–8.5), we investigated the impacts of post-fire management strategies, including no management and different reforestation options, on the forest carbon balance. Our results showed that the model accurately simulated unburnt vegetation structure. However, it overestimated fire carbon emissions compared to in-situ estimates. Post-fire carbon flux simulations revealed that avoiding salvage-logging of fire-surviving trees could result in the highest net carbon uptake in the near future (2019–2060). Reforestation strategies with a combination of conifer and broad-leaved trees consistently resulted in higher net C uptake than monoculture or mixed conifer options across all scenarios. Warming scenarios further accelerated carbon recovery, reducing the years needed to reach the carbon compensation point (CCP), i.e. the time when cumulative carbon uptake by reforestation balances the total carbon lost due to fire and post-fire emissions. Nevertheless, our study also revealed that the modelled rate of forest recovery was more rapid than observed. Our findings suggest that addressing specific model issues (e.g. fuel load and early stand development) can increase the robustness of modelled fire carbon emissions and CCP estimate
ISHLT consensus statement on the perioperative use of ECLS in lung transplantation : Part II: Intraoperative considerations
No full textThe use of extracorporeal life support (ECLS) throughout the perioperative phase of lung transplantation requires nuanced planning and execution by an integrated team of multidisciplinary experts. To date, no multidisciplinary consensus document has examined the perioperative considerations of how to best manage these patients. To address this challenge, this perioperative utilization of ECLS in lung transplantation consensus statement was approved for development by the International Society for Heart and Lung Transplantation Standards and Guidelines Committee. International experts across multiple disciplines, including cardiothoracic surgery, anesthesiology, critical care, pediatric pulmonology, adult pulmonology, pharmacy, psychology, physical therapy, nursing, and perfusion, were selected based on expertise and divided into subgroups examining the preoperative, intraoperative, and postoperative periods. Following a comprehensive literature review, each subgroup developed recommendations to examine via a structured Delphi methodology. Following 2 rounds of Delphi consensus, a total of 39 recommendations regarding intraoperative considerations for ECLS in lung transplantation met consensus criteria. These recommendations focus on the planning, implementation, management, and monitoring of ECLS throughout the entire intraoperative period
Impact of Fixation Protocols on Elemental Content in Human Sperm
No full textX-ray Fluorescence microscopy is a sophisticated advanced technique which can provide information regarding the concentration and the distribution of chemical elements within biological samples. It is increasingly used in the study of cells and tissues as it does not require the use of staining or fluorescent probes. For XRF measurements, sample preparation is a key step in the analytical process that affects all aspects of the analysis. Cells should be maintained in conditions that closely resemble physiological environments, but this can be challenging, especially under vacuum conditions. While numerous fixation protocols exist, finding one that works best for all cell types remains difficult. This study focuses on human spermatozoa, as they differ from other cell types in size, structure, and function. Furthermore, in human sperm, the presence and the balance of various chemical elements are crucial to their efficiency and success in reproduction. Our work aims at investigating the most suitable protocol for spermatozoa fresh cell fixation for XRF analyses at different energies; in particular, paraformaldehyde (PFA) 4% and methanol fixation are compared through XRF analyses at low and hard X-ray energy excitation, revealing light and trace elements. Although PFA is the most widely used chemical fixative for biological sample preparation, our results suggest that methanol is an excellent alternative for fixing human sperm for X-ray microscopy as it better preserves their elemental content while still maintaining an acceptably good morphology
