Search Results (1,055)

The spatial distribution of flammable tree species directly influences forest fuel structure and fire risk patterns. However, mixed pixels limit the ability of conventional classification methods to characterize continuous within-pixel variation in species composition, thereby constraining fine-scale forest mapping. To address this issue, this study developed a subpixel mapping framework for flammable tree species in Yajiang County, Sichuan Province, by integrating Sentinel-2 time-series data with a spectral mixing–unmixing strategy. Using 2019 Sentinel-2 time-series data and National Forest Inventory (NFI) data, temporal mixed samples with known abundance fractions were generated using a linear spectral mixing model. An XGBoost-based collaborative multi-regression framework was then applied to estimate the proportions of different tree-species endmembers within complex forest pixels. Quantitative evaluation using synthetic mixed samples showed that the model achieved stable unmixing performance across different random mixing scenarios. The best performance was obtained under the Mixed 2 scenario with a sample size of 250 K, reaching an R² of 0.821. The resulting maps revealed continuous spatial variation in the abundance and composition of flammable tree species. Mountain pine was the most widespread and dominant species, followed by spruce and mountain oak, whereas birch and fir mainly exhibited localized patchy distributions. An additional NFI-based categorical evaluation assessed the consistency of the final maps with real forest inventory records. The identification accuracies were 93.95% for pure stands and 91.22% for mixed stands, while the species classification accuracies were 87.28% for pure stands and 84.41% for dominant species in mixed stands. The proposed framework provides useful spatial information for regional forest fuel assessment and fire risk management. Full article

Neutron capture reactions provide essential nuclear physics input for modeling the synthesis of heavy elements in stars. The growing precision of stellar spectroscopy and isotopic measurements in presolar SiC grains now demands cross sections with improved accuracy over the full energy range, and access to unstable nuclei relevant to slow (s-) process branchings and the intermediate (i-) process. This article reviews recent progress in direct neutron capture measurements, focusing on time-of-flight (TOF) experiments at CERN n_TOF and complementary activation techniques. Substantial advances have been achieved for stable s-only and bottleneck isotopes, significantly improving constraints on s-process models. In parallel, the combination of high instantaneous neutron fluxes and advanced detector systems has facilitated first-time neutron capture measurements on several radioactive branching-point nuclei. Feasibility studies, however, reveal current limitations related to sample availability, background conditions, and restricted energy coverage. In this context, the complementarity between TOF and activation emerges as a central strategy. Future developments, including high-flux facilities and novel inverse kinematics experiments in ion storage rings, are expected to extend the boundaries of neutron capture measurements, overcoming current limitations and helping unlock new frontiers in our understanding of stellar nucleosynthesis. Full article

This study investigates the pressure-dependent structural, electronic, mechanical, and thermoelectric properties of LiYN (Y = Sr, Mg, Zn) half-Heusler compounds using first-principles calculations. The structural stability was analyzed by fitting the total energy versus volume curves using the Birch–Murnaghan equation of state, allowing the determination of equilibrium lattice parameters and bulk moduli at pressures of 0, 5, and 10 GPa. Elastic constants were calculated to assess the mechanical stability, and all compounds satisfy the Born stability criteria over the entire pressure range. The Pugh ratio (B/G) and Poisson’s ratio (ν) indicate that LiSrN, LiMgN, and LiZnN exhibit predominantly brittle behavior under 0 GPa. Electronic band structure calculations reveal that LiMgN and LiZnN exhibit direct band gaps, whereas LiSrN shows an indirect band gap. Increasing pressure leads to a systematic widening of the band gaps due to lattice compression. Thermoelectric properties were evaluated using the Boltzmann transport theory within the constant relaxation time approximation. The Seebeck coefficient, electrical conductivity, and figure of merit (ZT) were found to be strongly dependent on both temperature and pressure. Notably, at 300 K, the ZT values increase from 0.005, 0.35, and 0.54 at 0 GPa to 0.027, 1.12, and 1.13 at 10 GPa for LiMgN, LiSrN, and LiZnN, respectively. These results demonstrate that hydrostatic pressure significantly enhances the thermoelectric performance of LiYN compounds, highlighting their promising potential for thermoelectric energy conversion applications. Full article

One of the most important metrics for analyzing hardwood sawmill performance with respect to profitability is knowing the expected yield from any specific log. The Log Recovery Analysis Tool (LORCAT) is a spreadsheet-based sawmill simulation and analysis tool that was developed to provide this information. As such, LORCAT depends on recorded grade recovery data to determine the quality and volume using the NHLA grade of the sawn lumber. Recently, the grade recovery data of LORCAT was expanded to include beech (Fagus grandifolia) and paper birch (Betula papyrifa), allowing the software to simulate sawing and analysis of these species. While the data are based on North American species, grading systems, and economic assumptions, with differences in species, silvicultural, logging (bucking), and sawing practices acknowledged, LORCAT can be used to emulate the sawing of European logs. Overall, LORCAT can simulate and analyze the sawing of 13 common North American hardwood species (red oak, white oak, black oak, scarlet oak, chestnut oak, red maple, sugar maple, yellow poplar, American beech, paper birch, yellow birch, black cherry, and basswood) for small-end diameters ranging from 20 cm to 90 cm, and report the volume and the quality of lumber produced, as well as the volume and weight of residual products. Full article

Suberinic acids (SA) derived from birch outer bark are renewable feedstocks for bio-based polyols suitable for rigid polyurethane (PU) foams. Three SA fractions were prepared under different depolymerization conditions: acidification at pH 1 (SA1), pH 5 (SA2), and FeCl₃-assisted treatment (SA3), and their chemical composition was analysed by GC–MS, Py–GC/MS, and GPC–RID. Polyols derived from tall oil fatty acids (TOFA) or epoxidized TOFA with trimethylolpropane were used as the sole polyol components in foam formulations. The SA fractions differed in molecular weight distribution, affecting polyol processability. All foams exhibited similar limiting oxygen index (19–20) and cone calorimetry results, showing no statistically significant differences in flammability. This indicates that variations in depolymerization conditions, including polyphenolic content and removal of higher-molecular-weight fractions during FeCl₃ treatment, do not dominate fire performance under the studied conditions. SA3-based polyols showed the lowest viscosity and produced foams with optimal mechanical and thermal properties, while SA1 offered higher yield with comparable performance. These results demonstrate the feasibility of converting SA fractions into functional polyols for rigid PU foams and highlight the FeCl₃-treated SA3 fraction and SA1 as the most promising candidates for further development. Full article

Plant detritus plays a pivotal role in regulating soil nutrient dynamics within forest ecosystems. Understanding short-to-medium-term responses of soil-available nitrogen (AN) and phosphorus (AP) to altered detritus inputs is important for forest nutrient management. In this study, we investigated the effects of changing detritus inputs on soil AN and AP in two representative forest types in Northeast China—Korean pine (Pinus koraiensis Siebold et Zucc.) forest (KP) and Aspen (Populus ussuriensis Kom.)−birch (Betula platyphylla Sukaczev) forest (AB). Using the detritus input and removal treatments (DIRTs) method, we established six experimental treatments and measured soil ammonium nitrogen (NH₄⁺-N), soil nitrate nitrogen (NO₃⁻-N), and AP contents monthly from May to October. The results showed that significant differences in NH₄⁺-N, NO₃⁻-N, and AP contents were observed among treatments. Under the six DIRTs, the fluctuation ranges of NH₄⁺-N, NO₃⁻-N, and AP contents in KP soil were 1.16–12.52 mg/kg, 7.34–35.40 mg/kg, and 9.63–31.72 mg/kg, respectively. For AB soil, the fluctuation ranges of the above three nutrients under the six DIRTs were 2.94–13.17 mg/kg, 3.45–28.47 mg/kg, and 1.77–25.60 mg/kg, respectively. Root treatments exerted stronger effects on AN and AP than litter: root exclusion generally reduced NH₄⁺-N but increased NO₃⁻-N and AP, with the direction and magnitude of the response to this treatment varying with month and forest type, whereas litter treatments showed no consistent trends. The soil-available N:P ratio was lower in the KP forest than in the AB forest; root exclusion significantly reduced the N:P ratio in the AB forest but had no significant effect on that in the KP forest. In terms of seasonal dynamics, the study found that AN peaked in May and AP in July. In conclusion, these findings reflect the short-to-medium-term effects of plant detritus, forest type, and month on soil-available nitrogen and phosphorus, providing scientific insights into how detritus changes alter soil nutrients in temperate forests. Full article

The long-term storage of seeds is important for conserving native species, but its effectiveness depends on maintaining seed quality. This study assessed the impact of storage duration on seed quality in Alnus glutinosa (alder) and Betula pubescens (downy birch). Seed quality was evaluated using thousand-seed weight (TSW), moisture content (MC), tetrazolium (TZ) viability, and germination tests. Results from stored seed lots were compared with those from recently collected seeds. Moisture content, TZ viability, and germination were significantly affected by storage duration, although sensitivity analyses indicated that storage conditions, particularly lower temperature and airtight storage, may have contributed to improved seed viability in specific seed lots. A relationship between TZ viability and germination was observed, although this was influenced by zero values. Cold stratification improved germination in downy birch but did not compensate for reduced viability in older seed lots. These findings highlight the importance of storage conditions and species-specific pre-treatments and support the use of TZ testing as a rapid indicator of seed viability when used alongside germination testing. The results provide practical guidance for managing seed resources and maintaining reliable forest reproductive material supply. Full article

A nondestructive, rapid, and portable detection method for moisture content (MC) in living tree trunks remains unavailable. Tree radar, developed based on ground-penetrating radar (GPR) technology, represents a promising approach for tree trunk MC detection owing to its high penetration depth and low susceptibility to environmental interference. However, its application to living tree MC detection is constrained by curvature-induced wave propagation complexity, interspecific structural heterogeneity and the limited availability of labeled MC samples obtained through destructive coring, collectively resulting in poor model performance. The study proposed a novel GPR-based MC detection method employing a multi-scale one-dimensional convolutional neural network integrated with an attention mechanism and mixed data augmentation (mixed-MS1DCNNAM). GPR amplitude data extracted from the first 6.5 ns of B-scan signals were used to capture MC-related features via a custom program developed in MATGPR. A mixed model for four tree species with 15–30 cm diameters at breast height (DBH) achieved an R² of 0.7908 and an RMSE value of 0.1059, outperforming traditional models, with test metrics calculated at the tree level by averaging predictions from five directional GPR scans per tree. Furthermore, three DBH-specific sub-models (15–20 cm, 20–25 cm, and 25–30 cm) and four single-species sub-models were developed, yielding improved performance (R² ≥ 0.7246, RMSE ≤ 0.1033; RMSE ≤ 0.0959, MAE ≤ 0.0626, except for European white birch). These results highlighted the effectiveness of stratification by DBH class and tree species. Overall, this study effectively addresses aforementioned challenges and establishes a generalizable nondestructive approach for living trees under field conditions, facilitating sustainable forest management in tree growth monitoring, forest disaster monitoring, harvested timber storage and wood quality assessment. Full article

Introduction: The role of Collis gastroplasty has traditionally been reserved for patients with a shortened esophagus due to chronic gastroesophageal reflux disease (GERD). However, its necessity has been questioned, leading to a decline in popularity. This systematic review and meta-analysis aimed to evaluate the efficacy of hiatal hernia repair with fundoplication, with versus without Collis gastroplasty. Methods: A systematic search of Ovid MEDLINE, Ovid Embase, Scopus, Web of Science Core Collection, and the Cochrane Library (via Wiley) was performed in May 2025. Studies were included if they compared outcomes or the safety profile of Collis gastroplasty versus no Collis gastroplasty during fundoplication for hiatal hernia repair. Meta-analyses were conducted using a random-effects model and restricted maximum likelihood. Results: Of 664 unique results, 17 studies comprising 4048 patients were included. There was a female predominance (65.4%), with a weighted mean age of 58.9 ± 14.0 years and follow-up of 43.5 ± 43.1 months. Patients who underwent Collis gastroplasty represented 35.8% of the cohort. Nissen fundoplication was the most common procedure in both the Collis (91.9%) and non-Collis (84.5%) groups. Most studies had selection bias, in which only patients who did not have sufficient intraoperative intra-abdominal esophageal length underwent Collis gastroplasty. Recurrence rates were similar (13.5% vs. 13.2%). Collis gastroplasty was not associated with a reduction in hiatal hernia recurrence (OR 0.53, 95% CI 0.23–1.22). Symptom outcomes, including regurgitation (OR 0.53, 95% CI 0.05–5.39), reflux (OR 0.81, 95% CI 0.03–22.12), dysphagia (OR 1.12, 95% CI 0.62–2.04), and use of antireflux medication on follow-up (OR 1.15, 95% CI 0.62–2.15), were not significantly different. However, Collis gastroplasty was associated with a higher risk of complications, including overall complications (OR 2.63, 95% CI 1.55–4.46), leak (OR 3.35, 95% CI 1.11–10.05), and surgical site infection (OR 8.28, 95% CI 1.16–59.10). There were no significant differences in abscess formation (OR 5.97, 95% CI 0.77–46.49), length of stay (mean difference 0.36 days, 95% CI −0.30 to 1.01), readmission (OR 1.13, 95% CI 0.36–3.60), reoperation (OR 1.24, 95% CI 0.64–2.41), or mortality (OR 1.08, 95% CI 0.45–2.57). Conclusions: Collis gastroplasty was not associated with a decreased risk of hiatal hernia recurrence or improvement in other efficacy measures, but this is in the context of a strong component of selection bias. In this context, there may be a role for Collis gastroplasty in difficult cases if the rate of recurrence does not differ from those with sufficient length, but this must be balanced against a significantly increased risk of complications. Full article

The response of tree growth to environmental (climatic) changes has largely been analyzed through ring width–climate relationships, yet such analyses often lack the dynamic process of radial growth in response to environmental changes. Therefore, this study focuses on Korean pine (Pinus koraiensis Siebold & Zucc.) and white birch (Betula platyphylla Sukaczev) at three elevations (750 m, 950 m, and 1150 m) in the broadleaved Korean pine forest on the northern slope of Changbai Mountains, China. We systematically monitored cambial activity and the dynamics of xylem formation stages to analyze the different adaptation strategies of the two species in terms of phenology, cellular characteristics, growth rates, and climatic responses during cambial and xylem formation stages. The results showed that the phenological stages of xylem formation in Korean pine were more sensitive to elevation, while the phenological changes in birch were smaller, indicating greater growth stability. The seasonal dynamics of the number of xylem cell layers in both species followed a unimodal or sigmoid curve, but high elevations significantly inhibited the number of mature cell layers. Gompertz model fitting revealed that the maximum growth rate of Korean pine decreased significantly with increasing elevation, whereas no significant change was observed in birch. With increasing elevation, temperature emerged as the primary factor influencing cambial phenology and growth duration in both species, while precipitation dominated changes in growth rates. Xylem growth in Korean pine was co-regulated by growth rate (R² = 0.62) and growth duration (R² = 0.35), with tracheid diameter closely related to the duration of expansion (R² = 0.36). The regulatory pattern of xylem growth in birch was similar to that in Korean pine but with weaker correlations. In summary, Korean pine, as a coniferous dominant species, is more sensitive to temperature changes induced by elevation and adapts to elevational variations by adjusting phenology and cell development. In contrast, birch, as a broadleaved pioneer species, exhibits a high buffering capacity in xylem formation in response to elevational changes, thereby maintaining growth stability. The divergent growth strategies of the two species reveal the potential response pathways of temperate forest tree species to environmental changes and provide important insights for predicting the dynamics of broadleaved Korean pine forests. Full article

Background: Chemoimmunotherapy has improved survival compared with chemotherapy alone in phase III trials of advanced oesophago-gastric (OG) cancers; however, real-world UK data under National Institute for Health and Care Excellence (NICE) eligibility criteria remain limited. This study evaluated the effectiveness and safety of first-line pembrolizumab- or nivolumab-based chemoimmunotherapy in routine clinical practice. Methods: We conducted a retrospective, multi-centre cohort study of patients with unresectable or metastatic oesophageal, gastro-oesophageal junction, or gastric cancers treated with first-line chemoimmunotherapy at two UK tertiary centres between April 2021 and July 2024. Clinical, laboratory, radiological, and toxicity data were collected. Radiological outcomes were based on retrospective review of reports issued by consultant radiologists during routine clinical care. Overall survival (OS) and progression-free survival (PFS) were analysed using the Kaplan–Meier method, with exploratory analyses of prognostic factors. Results: Seventy-six patients were included (59.2% ≥ 65 years; 81.6% adenocarcinoma; 71.1% metastatic). At a median follow-up of 11 months, 46 deaths had occurred. Median OS was 16.0 months (95% CI: 11.0–20.9), and median PFS was 8.0 months (95% CI: 6.8–9.2). Disease control occurred in 80.3% of patients and was associated with improved OS compared with progressive disease (17.0 vs. 4.0 months; p < 0.001). Survival outcomes did not differ significantly by tumour site, histology, or immunotherapy agent. Immunotherapy-related adverse events occurred in 31 patients (40.8%), with grade ≥ 3 toxicities in 13.2% and two treatment-related deaths. Exploratory analyses suggested potential associations between survival and baseline lymphocyte count and neutrophil–lymphocyte ratio, although these did not reach statistical significance. Conclusions: In this real-world UK multi-centre cohort, first-line chemoimmunotherapy demonstrated survival outcomes comparable to pivotal clinical trials, with manageable toxicity. These findings support the use of chemoimmunotherapy in routine practice. Prospective collaborative studies incorporating robust biomarker evaluation are warranted to optimise patient selection and better define predictors of response and toxicity. Full article

Novel biobased materials and processing techniques are actively developed for sustainable coatings. This study investigated the potential mutagenicity of novel materials and derived dispersions used for biobased paper and wood coatings using a pilot 384-well test. The standard Ames test was performed for selected materials to compare and validate the results with the non-standard 384-well test. Salmonella Typhimurium strains (TA100 and TA98) were used for testing. Experimental dispersions were prepared using suberin and betulin extracted from outer birch bark. The test set of seven samples (n = 7) included commercial reference samples and additives. Both test methods were suitable for these samples but also highlighted method-specific differences and challenges. For suberin-derived materials and betulin at 0.5–1% concentration, neither of the tests indicated mutagenicity. In the case of some industrial samples, the 384-well test and the standard Ames test gave clearly contradictory results. These can be explained by the test limitations, such as the sample color or compositional instability of dispersions. To summarize, this study indicated the need to test the novel coating materials with multiple concentrations, and several bacterial strains carrying different types of genetic mutations, as well as to use complementary genotoxicity tests for a more accurate toxicity profile. Full article

In the Scrambled Sentences Task (SST), a widely used experimental paradigm for measuring negative interpretation bias (IB), participants are shown sets of ‘scrambled’ words that can be rearranged into either negative or positive sentences. The SST is traditionally administered with time limits, cognitive load and negative mood induction. Yet, whether these procedural features are required in all contexts remains uncertain. We tested whether a modified SST (SST-M), lacking time limits, cognitive load and mood induction, can be sufficient to detect associations between IB and current psychopathology by examining validity evidence and reliability of scores. Sixty-six Canadian university students (80.3% Women) completed the SST-M and measures of anxiety, depression, negative affect, and growth mindset. Findings offer preliminary validity evidence supporting the interpretation of SST-M scores as reflecting IB in a student sample. Results yielded excellent internal consistency and expected associations with anxiety, depression, negative affect, and growth mindset. The SST-M also displayed incremental associations above and beyond demographic covariates and negative affect. Our findings suggest that IB can be reliably detected, in at least some samples, without time limits, cognitive load and mood induction. The SST-M is an easy-to-administer measure that lowers data collection barriers, providing the potential to advance research across broader populations. Full article

The black carbon (BC) emission resulting from human activity comes mainly from fossil fuels and solid biomass burning, as well as transport fuels due to incomplete combustion. The biggest sources of BC pollution are currently diesel transport and domestic heating appliances burning solid fossil fuels or biomass. Firewood and pellet fuels were used for this BC research. The study used four domestic heating appliances using wood and agricultural waste pellets, as well as several types of firewood. The tests used a gravimetric particulate analysis method to determine the total amount of particulate matter. In further physical and chemical analyses, the emissions are broken down into components, i.e., substances of known composition that can be separated from the sample and weighed. In our study, the BC emissions varied from 0 to 120 mg/MJ depending on the type of boiler (automatic or manual), the combustion mode (based on oxygen supply), and the type of fuel. Emissions varied from 0–8 mg/MJ in a modern pellet-fired and automatically-controlled boiler, and from 1–25 mg/MJ in a wood-fired water heating boiler, with the highest emissions found for softwood (spruce). In the pellet stove with automatic feeding and control, BC emissions varied between 1 and 120 mg/MJ, with the highest emissions detected for wood pellets, and in the wood-burning fireplace, the emissions varied between 6 and 80 mg/MJ, with the highest emissions detected for birch firewood. Full article

Microbial nutrient cycling in afforested mine soils may be affected by the plant litter quality. This study investigated how different tree species—Scots pine (Pinus sylvestris), silver birch (Betula pendula), European larch (Larix decidua), and black alder (Alnus glutinosa)—influence microbial carbon (C), nitrogen (N), and phosphorus (P) limitations in reclaimed sandy mine soils. We combined substrate-induced respiration (SIR) and ecoenzymatic stoichiometry (EES) to diagnose these metabolic constraints. The SIR analysis revealed a universal primary limitation by labile C across all tree species, with glucose addition stimulating respiration by 271%–333%, regardless of the soil organic carbon content. However, EES revealed distinct secondary nutrient constraints driven by species-specific litter quality. Alder stands exhibited severe P limitation, likely due to high P demand for symbiotic N-fixation and intense competition for P between trees and microbes. In contrast, birch stands showed stoichiometric homeostasis and a slight N deficiency. Coniferous species exhibited P limitation and low enzymatic activity, indicating a strategy focused on intensive nutrient acquisition under low-energy conditions associated with recalcitrant needle litter. These findings demonstrate that while energy limitation is a universal constraint in mine soils, tree species determine the nature and intensity of secondary nutrient limitations due to differences in litter stoichiometry. Full article