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Samaras are known for their elegant and robust autorotation, a resilience that persists in the adverse conditions imposed by high-speed raindrops. Like flying insects, samaras descending from tall trees are likely to be struck by raindrops in an intense storm. In this study, we detail the collision dynamics for impact regions across the samara body and the drop-shedding mechanisms that samaras exhibit to return to autorotation. Impacts across the samara body can pitch the samara up to 60 degrees and, in some cases, induce spanwise roll. Raindrops may shatter or remain intact upon impact, pushing the undamaged samara downward before autorotation is recovered. Drops that strike near the wingtip elicit the greatest recovery distance, while impacts onto the nutlet mass are the least disruptive to the samara and most likely to cause the drop to induce fragmentation. Faster drops allow for quicker drop shedding and a subsequent rapid return to autorotation in less than 50 ms. Our results indicate that samaras are robust to raindrop impacts and consistently recover autorotation, resulting in a minor reduction in dispersal distance. To recover, the entire drop is shed from the spinning samara over a time closely tied to the shedding mode and ensuing drop rejection forces. [ABSTRACT FROM AUTHOR]

The Kepler problem is named after Johannes Kepler, who proposed Kepler's laws of planetary motion. Kepler problem is a special case of the two-body problem in classical mechanics. The two bodies interact by a central force F that varies in strength as the inverse square of the distance r between them. Here, we are looking for the equation of motion using the Lagrangian formulation and its solution using a numerical approach. Though the general theory of relativity provides more accurate solutions to the two-body problem, especially in strong gravitational fields, here we are exploring numerical methods followed by correction term in potential energy, inversely proportional to the cube of the radius for perihelion motion. [ABSTRACT FROM AUTHOR]

Among the species used for syrup production, sugar maple (Acer saccharum Marsh.) is preferred by producers, while red maple (Acer rubrum L.) is considered less productive in terms of sap yield and sugar content. This study aims to measure the volume and physicochemical characteristics of the sap produced from two red maples and two sugar maples during the 2023 sugar season in a commercial sugarbush in Laterrière (QC, Canada). Sap exudation was measured continuously with the gravity method using automatic rain gauges. Sap production was discontinuous and heterogeneous, reaching 2.6 L during the most productive day. No significant difference was found in the daily production between species, but we observed a difference in the cumulative sap production (7 L in red maple vs. 13.5 L in sugar maple) due to a longer period of sap exudation in the latter. Despite daily variations in pH, Brix values, sucrose concentration, osmolality, and conductivity, no differences in physicochemical characteristics were detected between species. [ABSTRACT FROM AUTHOR]

Some natural wind-borne plants spread their seeds in a mode of autorotation, for example, maple, pterocarya stenoptera, and tristellateia. However, these wind-borne seeds have different numbers of wings. The current work focuses on the effects of wings number on the flight performance of autorotating seeds. Experiment and numerical simulation are used to analyze the aerodynamic performance of tristellateia seeds with different numbers of wings. In the free fall experiments, it is found that reducing the wings number leads to larger wing loadings, larger stable descending velocities, and larger spinning rates. The growth rate of descending velocity and spinning rate are related to the wings number. However, as the number of clipped wings increases, the seeds are more likely to fall into unsteady rotation even free fall. Numerical simulations are used to analyze the flow field around the rotating tristellateia seeds. It finds that seeds with clipped wings have larger pressure difference between the upper and lower wing surfaces, which contributes to larger lift. Three kinds of vortex systems occur on the rotating seeds: the leading-edge vortex, the wing tip vortex, and the separated vortex. Seeds with different clipped wings present various vortex morphology and structure. A stable separated vortex ring dominates the stable autorotation of tristellateia seeds. However, an unstable separated vortex emerges on the seeds with less wings, which makes these seeds difficult to achieve stability. [ABSTRACT FROM AUTHOR]

Asymmetric warming refers to the difference between the increase in daytime maximum temperature and the increase in nighttime minimum temperature and has been documented in temperate regions. However, its impacts on seedling growth have been largely ignored. In this study, seedlings of a widely distributed tree species, Acer mono Maxim., were exposed to both symmetric warming (SW) and asymmetric warming scenarios (day warming [DW], night warming [NW] and diurnal asymmetric warming [DAW]). Compared to control, all warming scenarios were found to enhance belowground biomass. DW promoted the seedling growth, while NW reduced the stem biomass. DAW did not impact the total biomass relative to the control. Compared to SW, DAW advanced phenology, increased indole‐3‐acetic acid content and chlorophyll content, which enhanced total biomass and stored more NSC in the root. Future DAW would be not beneficial to the growth of A. mono seedlings by comparing with the control. This research encourages further exploration of tree growth experiments under asymmetric warming conditions, as most studies tend to underestimate the warming effects on plant growth by focusing on SW. Incorporating the responses of seedling physiology and growth to non‐uniform diurnal warming into earth system models is crucial for more accurately predicting carbon and energy balances in a warmer world. Summary statement: We found that asymmetric warming advanced phenology, increased indole‐3‐acetic acid content and chlorophyll content, which enhanced total biomass and stored more non‐structure carbohydrate in the root of Acer mono, compared to symmetric warming. This research encourages further exploration of tree growth experiments under asymmetric warming conditions, as many studies tend to underestimate the effects of warming on plant growth based on symmetric warming. [ABSTRACT FROM AUTHOR]

Background: Urban trees provide many environmental benefits but often face challenging growing conditions like waterlogged soils. How tree root systems respond to waterlogging impacts tree performance and survival, yet this has received little attention. Our goal was to identify how the roots of temperate urban tree species respond and recover to waterlogging. Methods: We monitored the responses and recovery of 2 contrasting maple and magnolia species pairs that differ in their reported waterlogging tolerance to a 2-week waterlogging period, measuring belowground stress indicators, fine-root mortality, and aboveground responses including leaf-level photosynthesis, leaf loss, and stem growth. Results: Though silver maple experienced a temporary reduction in photosynthetic activity during waterlogging, it exhibited no fineroot mortality, and photosynthetic activity recovered after a 10-day recovery period. In contrast, sugar maple showed high fine-root mortality, decreased photosynthetic activity, and significant leaf loss, with no recovery in fine-root growth or photosynthetic activity after the recovery period. Both magnolia species showed high fine-root mortality and reduced photosynthesis during the waterlogging period. However, after the 10-day recovery period, both magnolias also showed new fine-root growth and increased photosynthetic activity. Conclusion: The species studied here showed a wide range of fine-root response and recovery strategies to waterlogging, and this was mirrored in their aboveground performance. Future work clarifying the mechanisms driving these different strategies, such as silver maple's ability to maintain fine roots and mitigate internal tissue damage, will help us to further understand species differences in waterlogging tolerance and better inform urban tree selection for repeatedly flooded soils. [ABSTRACT FROM AUTHOR]

Trace elements in tree nut oils may be toxic for humans and catalyze the auto-oxidation of the oils, affecting their stability. These elements have not been comprehensively characterized. In this study, we prepared tree nut oils from tree nuts (camellia, acer truncatum, shiny leaf yellow horn, and pecan seeds, as well as walnuts and Brazil nuts) by cold-pressing and determined As, Cd, Cu, Fe, Mn, Pb, Se, and Zn in these seeds and their oils and residues. Moreover, we investigated the elemental migration from seed to oil. The migration of all measured elements from seed to oil was <2%, where Cu exhibited the lowest migration from 0.09 to 0.31%. Moreover, we studied the effect of preheating (25–150 °C) the seeds upon their elemental migration. The Cu, Fe, Mn, and Zn contents increased with the temperature in all tree nut oils. The migration of toxic As, Cd, and Pb did not significantly differ with temperature, suggesting that temperature does not affect the release of these elements from nuts to oil. [ABSTRACT FROM AUTHOR]

This paper explores the application of automated reasoning tools, specifically those implemented in GeoGebra Discovery, to the perimeter-area inequality in triangles. Focusing on the computational complex and real algebraic geometry methods behind these tools, this study analyzes a geometric construction involving a triangle with arbitrary side lengths and area, investigating the automated derivation of the relationship between the area and perimeter of a triangle, and showing that only equilateral triangles satisfy the exact perimeter-area equality. The main contribution of this work is to describe the challenges, and potential ways to approach their solutions, still posed by the use of such automated, symbolic computation, methods in dynamic geometry, in particular concerning the discovery of loci of points that satisfy specific geometric conditions, suggesting relevant improvements for the future development of these symbolic AI-based educational tools in geometry. [ABSTRACT FROM AUTHOR]

Laser thin layer deposition technologies were applied to develop organic heterostructures on flexible transparent conductive electrode (TCE). Flexible substrates such as flexible glass (FG), polyethersulfone (PES), amorphous polyethylene terephthalate (PET-A) and biaxially-oriented polyethylene terephthalate (PET-B) were employed to assess the influence of the substrate type on the optical and electrical characteristics of the organic devices. For comparison reason, the organic heterostructures were fabricated on rigid glass substrate and commercially available indium tin oxide (ITO)-coated PET. Hence, flexible and rigid glass substrates were coated with ITO film by pulsed laser deposition (PLD) at low fluence, subsequently a blend layer based on zinc phthalocyanine (ZnPc) and N, N′-bis-(1-dodecyl)perylene-3,4,9,10 tetracarboxylic diimide (AMC14) being deposited by matrix assisted pulsed laser evaporation (MAPLE) on the TCE film. The investigations evidenced that the roughness and the substrate type can strongly influence the properties of the ITO layer deposited by PLD as well as the optical and electrical characteristics of the organic heterostructures based on the blend layer deposited by MAPLE. Thus, the lowest roughness (0.8 nm) and the best Hall mobility (41.9 cm2/Vˑs) were achieved for ITO coatings deposited on flexible glass substrate. Also, the highest current density value (9.3 × 10− 4 A/cm2 at 0.5 V) was reached for the organic heterostructures fabricated on this type of flexible substrate. [ABSTRACT FROM AUTHOR]

Changes in vegetation activities driven by climate change serve as both a sensitive indicator and a key driver of climate impacts, underscoring the need for accurate phenological predictions. Delays in leaf senescence due to rising air temperatures increase the risk of damage from early frost, potentially affecting growth and survival in subsequent years. This study aimed to quantify long-term changes in leaf senescence timing for palmate maple and ginkgo trees, explore their associations with environmental factors, and compare the performance of multiple modeling approaches to identify their strengths and limitations for phenological predictions. Using data from 48 sites across South Korea (1989–2020), this study analyzed trends in the timing of leaf senescence for maple and ginkgo trees and compared the performance of process-based models (CDD_T, CDD_P, TP_T, TP_P), a linear regression model, and machine-learning models (random forest, RF; gradient-boosting decision tree, GBTD). Leaf senescence timing for both species has progressively been delayed, with ginkgo trees showing a faster rate of change (0.20 vs. 0.17 days per year, p < 0.05). Delayed senescence was observed in most regions (81% for maple and 75% for ginkgo), with statistically significant delays (p < 0.05) at half of the sites. Machine-learning models demonstrated the highest training accuracy (RMSE < 4.0 days, r > 0.90). Evaluation with independent datasets revealed that the RF and process-based TP_P (including minimum temperature and photoperiod) using a site-specific approach performed best (RMSE < 5.5 days, r > 0.75). Key environmental factors identified by RF included autumn minimum or mean temperatures and a summer photoperiod. By conducting this comparative assessment, the study provides insights into the applicability of different modeling approaches for phenology research and highlights their implications for vegetation management and climate change adaptation. [ABSTRACT FROM AUTHOR]

Tetracentron sinense is a tall deciduous tree and represents the only remaining species of Tetracentron. Currently, the spatial distribution pattern of T. sinense and its associated influencing factors remain unclear, thus hindering its protection and rational utilization. In this study, we employed the point pattern method to analyze the spatial distribution patterns of four representative populations of T. sinense distributed in Baima Snow Mountain, Dafengding, Leigong Mountain, and Foping in China. The results reveal that the T. sinense populations in Baima Snow Mountain, Dafengding, and Leigong Mountain exhibited an aggregated distribution on small (0–10 m) or specific scales, with their spatial distribution patterns shifting from aggregated to random as the scale increased. In contrast, the population of T. sinense in Foping showed a random distribution at all scales. In relation to the factors influencing the spatial distribution patterns of T. sinense, we found that young trees played a crucial role and had a substantial impact on their distribution. Furthermore, adult trees contributed to the aggregated distribution of T. sinense saplings on smaller scales (0–10 m). Additionally, we identified Acer erianthum, Prunus conradinae, and Rhododendron anthosphaerum as key associated species that influenced the formation of spatial distribution patterns of T. sinense. Finally, air humidity and soil moisture content were found to exert a significant effect on the spatial distribution patterns of T. sinense populations. For the protection of T. sinense in situ, it is necessary to increase the number of young trees, enhance the availability of microhabitat factors for its seedlings, and utilize key companion species to promote heterogeneity, which can optimize resource utilization and foster population rejuvenation. [ABSTRACT FROM AUTHOR]

In this article, we determine various analytical solutions for the (4+1)-dimensional Fokas equation, a significant model in mathematical physics with numerous applications in nonlinear dynamics. Utilizing multiple integration techniques such as the improved F-expansion technique and the Jacobi elliptic function method, we retrieve an array of solution types, including traveling waves, periodic solutions, bell-shaped waves, rational functions, and both kink and anti-kink structures. We further explore the complex nature of these solutions through their graphical representations. By applying Maple, we visualize our results in three-dimensional (3D), and two-dimensional (2D) formats to illustrate the dynamic behavior of these solutions across various parameters and initial conditions. Our findings provide deeper insights into the properties of the Fokas equation and offer a valuable reference for further studies in nonlinear wave phenomena.

Urbanization is transforming landscapes globally, altering environmental conditions that affect ecosystem functioning, particularly in urban areas where trees are crucial for regulating microclimates, improving air quality, and sustaining biodiversity. This study investigates the environmental differences and tree leaf structure and morphology in urban and suburban sites in the Chicago Metropolitan Region. The leaf functional traits of Norway Maple and Little − leaved Linden were studied in three locations in the summer of 2023: an urban park (University of Illinois Chicago, Chicago, IL), a suburban park (Morton Arboretum, Lisle, IL), and a suburban residential site (Lombard, IL). The urban site had higher daytime and nighttime air, and land surface temperatures compared to the suburban sites with significant fluctuations observed across the sites. Cumulative growing degree days, a measure of potential photosynthetically active days, were also higher in the urban park than in the suburban sites between March and August. Norway Maple trees growing in the urban site displayed higher specific leaf area (SLA) and lower leaf dry matter content (LDMC) than in the suburban sites, resulting in thinner leaves. Similarly, Little−leaved Linden trees in the suburban residential site displayed higher SLA and lower LDMC than those in the suburban park. The values of gas exchange traits − namely photosynthetic assimilation, transpiration rates, and stomatal conductance − of Norway Maple were higher at the urban site compared to suburban sites as temperatures increased during the summer. Norway Maple gas exchange values decreased as the growing season progressed, as expected by ontogeny. In contrast, Little−leaved Linden maintained similar leaf gas exchange values throughout the growing season. Both species in the urban site exhibited lower instantaneous water use efficiency and reduced LDMC, suggesting greater water loss in response to elevated temperatures compared to suburban park and residential sites. Comparisons with existing global trait databases emphasize the need for localized data to accurately capture site−specific responses. Although some traits aligned with database values, others deviated significantly, underscoring the importance of comprehensive, site−specific datasets for robust ecosystem modeling and management strategies. [ABSTRACT FROM AUTHOR]

Sooty bark disease is an invasive disease causing significant mortality of sycamore maple (Acer pseudoplatanus L.) in Europe, where it is emerging due to increasing drought and heat events. The causal agent, Cryptostroma corticale (Ellis & Everh.) P. H. Greg. & S. Waller, is a fungus endemic to the Great Lake region in eastern Canada, where it does not appear to cause disease within its natural host range (e.g. sugar maple, Acer saccharum Marshall). Sooty bark disease was reported causing mortality on sycamore maple and additional species within Washington State beginning in 2017. In summer 2022, sooty bark disease was found on a sycamore maple near Vancouver, representing the first report of the disease and causal agent within the province of British Columbia (BC). In this study, we identify the causal agent of sooty bark disease by morphological and molecular methods and confirm its pathogenicity in a controlled growth chamber experiment fulfilling Koch's postulates on sycamore maple. Cryptostroma corticale has so far been found in BC on sycamore maple, Norway maple (A. platanoides L.) and bigleaf maple (A. macrophyllum Pursh). Sooty bark disease has been previously shown to increase in severity and occurrence under drought and warm conditions; we anticipate rising sooty bark disease cases as BC experiences increasingly frequent and extreme summer droughts and heat events. [ABSTRACT FROM AUTHOR]

Front cover: This depicts a seashore in late autumn, where maple leaves resembling neurons are tinged with autumn red. In the distance, you can see an island, which is a whole brain map of Drosophila (Dorkenwald et al. (2024) Nature 634: 124‐138, DOI: 10.1038/s41586‐024‐07558‐y), entirely composed of neuron‐like maple leaves. Fly whole brain map: Adapted from Figure 1(a) of © Dorkenwald et al. (2024) Nature 634: 124‐138, DOI: 10.1038/s41586‐024‐07558‐y. Licensed under CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Designed by TRAIS Co., Ltd. (Kobe, Japan). [ABSTRACT FROM AUTHOR]

Monitoring of emerging plant diseases in the Apennine mountains (central Italy) identified Cryptostroma corticale as the cause of the disease sooty bark of maple trees. The identified sites were located in rural or forested areas, next to buildings, in villages or suburbs, and one site was in a forest. Samples of symptomatic tissues were taken from Acer pseudoplatanus and/or A. campestre, as well as asymptomatic samples from A. campestre and Aesculus hippocastanum. All samples tested positive to a species- specific qPCR assay for the presence of C. corticale, indicating wide incidence of the disease in the northern Apennines of Italy, after attempted eradication of the first small group of infected plants were found in 2012. [ABSTRACT FROM AUTHOR]

Hydroxyapatite (HAp) is one of the most widely studied materials for utilization in the development of artificial implants. Research is mainly aimed at the production and modification of HAp coatings for simplification of the deposition process, cost reduction, and increase in biocompatibility. In this paper, the authors deposited HAp synthetic microparticles by means of matrix-assisted pulsed laser evaporation (MAPLE) on Ti6Al4V alloy plate substrates and obtained uniform HAp coatings without further treatment or modifications. The authors utilized a tunable pulsed laser to adjust its wavelength to the selected solvents, in order to optimize the process for deposition speed and quality. The following solvents were used as matrices: deionized water, isopropyl alcohol, and a 3:2 mixture of isopropanol:acetonitrile. Obtained coatings were examined by means of scanning electron microscopy, Raman spectroscopy, X-ray diffraction, and profilometry in order to evaluate coating quality, uniformity, and structural integrity. MAPLE deposition allowed the acquisition of approx. 200 nm thick coatings for water and isopropanol matrices and approx. 320 nm for isopropanol:acetonitrile matrix, which indicates an increase in deposition rate by 37%. The obtained coatings meet requirements for further biocompatibility testing, material modification, and composite synthesis. [ABSTRACT FROM AUTHOR]

Urbanization has increased wealth disparity within the United States, impacting the urban landscape and species interactions. In particular, the interactions between street trees and the arthropod communities that live among them may be modified by both human population densities across urban to suburban locations, as well as income levels within these areas. We examined the effect of land use type (urban vs. suburban) and median household income on variation in leaf damage and arthropod abundance of red maples (Acer rubrum) in the District of Columbia metropolitan region. We compared these levels of leaf damage to rates observed in a nearby temperate deciduous forest. We predicted leaf damage would be positively correlated with urbanization (forested < suburban < urban) and negatively correlated with neighborhood income level (low > medium > high). Instead, we observed higher levels of leaf damage on trees in the forest environment compared to the urban and suburban areas. Leaves from urban medium and high-income areas were less likely to exhibit herbivore damage than those from suburban areas. Of the leaves with damage, those in urban high-income and suburban low-income areas exhibited the most leaf area missing. These trends may be related to specific factors associated with urbanization and income level, such as impervious surface coverage and tree coverage. This study highlights differences in biotic interactions across individual neighborhoods and the importance of including socio-economic variables when examining species interactions in urban environments. [ABSTRACT FROM AUTHOR]

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A family of Bohemian matrices is a set of matrices where the entries are independently sampled from a finite set, usually integers, of bounded height. Such families arise in many applications (e.g. compressed sensing) and the properties of matrices selected "at random" from such families are of practical and mathematical interest. Studying such matrices leads to many unanswered questions. In this paper, we state a new problem arising from the results obtained in a previous work concerning the maximal height of the characteristic polynomials of this family. We present a challenge with a computational flavour. More precisely, we describe, and illustrate by means of some experiments--executed with Maple--the problem of analyzing the behaviour of the set of heights, not only the maximal, of the characteristic polynomials of a family of upper Hessenberg Toeplitz structured Bohemian matrices. [ABSTRACT FROM AUTHOR]

In the present study, 20 sycamore maples (Acer pseudoplatanus L.) were evaluated on eight plots (160 trees) affected by sooty bark disease (SBD), caused by Cryptostroma corticale (Ellis & Everh.) P.H. Greg. & S. Waller in Northern Bohemia, Czech Republic. Mortality and presence of common pest taxa were assessed for each tree. Data were statistically evaluated using frequency and principal component analyses. The presence of C. corticale and Prosthecium pyriforme Jaklitsch & Voglmayr were positively related, with a significantly higher occurrence on dead trees. Rhytisma acerinum (Pers.) Fr. and Aceria macrorhyncha Nalepa were also positively related. However, the presence of Drepanosiphum platanoidis Schrank was not clearly related to the other evaluated taxa. Furthermore, C corticale was not present on Norway maple trees (Acer platanoides L.) growing on the plots. The results suggest that (i) the mortality of the sycamore was caused by C. corticale, while P. pyriforme was only an accompanying weak pathogen; (ii) R. acerinum, A. macrorhyncha, and D. platanoidis did not cause the mortality of the sycamore and their presence was not related to C. corticale infection; and (iii) planting more resistant maple species on sites susceptible to attack by SBD, particularly when stressed by drought, is recommended. [ABSTRACT FROM AUTHOR]

The visual morphology of trees significantly impacts urban green micro-landscape aesthetics. Proximity to tall buildings affects tree form due to competition for space and light. The study investigates the impact of tall buildings on six visually morphological traits of eight common ornamental species in urban micro-landscapes in Beijing, with the distance and direction between trees and buildings as variables. It found that as trees grow closer to buildings, most angiosperms show increased crown asymmetry degree and crown loss, and reduced crown round degree and crown stretch degree (i.e., Sophora japonica L. and Acer truncatum Bunge saw a 52.26% and 47.62% increase in crown asymmetry degree, and a 20.35% and 21.59% decrease in crown round degree, respectively). However, the pattern of crown morphological changes in gymnosperms is poor (the closer the distance, the lower the height-to-diameter ratio of Pinus tabuliformis Carr., while the height-to-diameter ratio of Juniperus chinensis Roxb. significantly increases). In terms of orientation, gymnosperms on the west side of buildings have a greater crown asymmetry degree. It suggests that planting positions relative to buildings affect tree morphology. Recommendations include planting J. chinensis closer to buildings but keeping angiosperms like Fraxinus velutina Torr., S. japonica, and A. truncatum more than 3 m away to ensure healthy crown development. [ABSTRACT FROM AUTHOR]

In this article, we determine various analytical solutions for the (4 + 1) -dimensional Fokas equation, a significant model in mathematical physics with numerous applications in nonlinear dynamics. Utilizing multiple integration techniques such as the improved F-expansion technique and the Jacobi elliptic function method, we retrieve an array of solution types, including traveling waves, periodic solutions, bell-shaped waves, rational functions, and both kink and anti-kink structures. We further explore the complex nature of these solutions through their graphical representations. By applying Maple, we visualize our results in three-dimensional (3D), and two-dimensional (2D) formats to illustrate the dynamic behavior of these solutions across various parameters and initial conditions. Our findings provide deeper insights into the properties of the Fokas equation and offer a valuable reference for further studies in nonlinear wave phenomena. [ABSTRACT FROM AUTHOR]

In the present study, we quantified floral resources (nectar and pollen production) and their quality (nectar sugar composition, pollen protein content, pollen amino acid composition) in five Acer species (f. Sapindaceae) growing in forests and commonly planted in urban areas in the temperate zone. Acer trees provide high amounts of sugars and/or pollen. No nectar was produced by A. negundo flowers. The other species produced nectar in functionally female flowers. The floral nectar was composed of sucrose, glucose, and fructose and was classified as hexose-rich or sucrose-rich. The pollen of all the Acer species contained essential amino acids. Acer trees should be planted for improvement of cost-effective food resources in various landscape types (agroforestry, urban areas), with the exception of A. negundo (an invasive species with no nectar available). However, maple trees alone are not sufficient to support pollinators, and other plant species flowering before and after Acer spp. should be planted to ensure a continued supply of food for pollinators. [ABSTRACT FROM AUTHOR]

Nowadays, the development of devices based on organic materials is an interesting research challenge. The performance of such devices is strongly influenced by material selection, material properties, design, and the manufacturing process. Usually, buckminsterfullerene (C60) is employed as electron transport material in organic photovoltaic (OPV) devices due to its high mobility. However, considering its low solubility, there have been many attempts to replace it with more soluble non-fullerene compounds. In this study, bulk heterojunction thin films with various compositions of zinc phthalocyanine (ZnPc), a perylene diimide derivative, or C60 were prepared by matrix-assisted pulsed laser evaporation (MAPLE) technique to assess the influence of C60 replacement on fabricated heterostructure properties. The investigations revealed that the optical features and the electrical parameters of the organic heterostructures based on this perylene diimide derivative used as an organic acceptor were improved. An increase in the JSC value (4.3 × 10−4 A/cm2) was obtained for the structures where the perylene diimide derivative acceptor entirely replaced C60 compared to the JSC value (7.5 × 10−8 A/cm2) for the heterostructure fabricated only with fullerene. These results are encouraging, demonstrating the potential of non-fullerene compounds as electron transport material in OPV devices. [ABSTRACT FROM AUTHOR]

[Objective] This study explored the effects of arbuscular mycorrhizal (AM) fungi on the growth and decomposition of dead leaves of Acer truncatum and determined the relationship between AM fungi and the growth status of Acer truncatum. [Method] The Acer truncatum seedlings were subjected to two treatments of arbuscular mycorrhizal fungi (AMF) and control without fungi (CK) . In the AMF treatment, Rhizophagus intraradices (Ri) was added to the sterilized substrate. In the CK treatment, sterilized Ri and fungicide filtration were added. At the same time, two decomposing boxes containing dead leaves of Acer truncatum were placed in two pots for both treatments. After 180 days of growth, growth index and nutrient contents of seedlings, as well as nutrient contents of dead leaves of Acer truncatum were determined. The decomposition amounts of dead leaves at different particle sizes and their remaining quantities were calculated. Redundancy analysis was conducted to examine the correlations between growth status, nutrient contents and decomposition rates of dead leaves. [Result] (1) Compared to CK, AMF treatment significantly enhanced fresh and dry masses and contents of total nitrogen, total phosphorus and total potassium roots and total phosphorus in leaves. There were no significant differences in plant height, ground diameter and leaf total nitrogen content. Total potassium content in leaves was significantly decreased. (2) Compared with CK, total decomposition capacity of dead leaves treated with AMF was significantly increased. The mass of dead leaves with size larger than 0. 15 mm was notably reduced while that of 0. 25 μm-0. 15 mm showed significant increases. (3) Compared to CK, AMF treatment enhanced the release of polyphenols and mitigated the accumulation of total nitrogen in withered leaves, while it had no significant impacts on tannin, cellulose, total phosphorus, total potassium and organic carbon. (4) The correlation analysis revealed that total nitrogen in dead leaves had a positive association with total potassium content in leaves and negative correlations with biomass and nutrient contents in roots and leaves. The accumulation coefficients of polyphenols in dead leaves exhibited inverse relationships. [Conclusion] The ino-culation of AM fungi enhanced the decomposition process of dead leaves, influenced the nutrient availability in dead leaves, and facilitated the growth and development of Acer truncatum. [ABSTRACT FROM AUTHOR]

A survey conducted in the 1920s, prior to the chestnut blight, indicated that chestnuts and oaks were codominant canopy species in White Oak Canyon, Shenandoah National Park, Virginia. A second survey in 1977 suggested that chestnuts were being replaced by tree species present before the blight, particularly oaks. In 2021, we resurveyed the 10 sites included in our 1977 survey and also recorded canopy and understory trees that grew above remnant chestnut sprouts. The canopy changed more substantially during the second interval (since 1977). Birch and maples were now more abundant. Hemlock declined, and oaks were less common in the canopy. In general, the trees considered as early to mid-successional have replaced oaks and hemlock. Chestnut sprouts have become much less common since 1977, presumably as repeated cycles of diebacks have weakened rootstocks. Those sites where chestnut sprouts have persisted until 2021 differed from neighboring sites without them. Chestnut sprouts were rare in sites with birch and hemlock; chestnut has persisted in locations with red oaks in the canopy and with few other understory competitors. This survey has been conducted over a longer time interval than previous studies that asked similar questions and our results suggest that changes to the forest composition following the loss of the American chestnut may be greater than previously recognized although the relative contribution of losing this codominant species is unclear. [ABSTRACT FROM AUTHOR]

Flatheaded borers (FHB; Chrysobothris spp.), are woodboring-beetles that lay their eggs in the bark and cambium of deciduous trees in North America. Females often target stressed host-plants for oviposition. The reason why is unknown; however, stressed plants often suffer various induced phytochemical changes that may enhance larval infestation success depending on the stressor such as induced upregulation of defenses, reallocation of nutrients, and changes to volatile organic compound (VOC) emissions. To understand attraction of FHB to specific stress-induced changes, we analyzed phytochemical changes associated with stress treatments and attractiveness maple trees to FHB. Trees were stressed by: (1) chemical stress (pelargonic acid herbicide), (2) physical stress (physically removing leaves), and (3) physical stress (removing portions of bark near the root crown). After reflush of defoliated trees, bark tissues where FHB larvae feed were analyzed for nutritional changes (carbon and nitrogen), anti-nutritive changes (polyphenols and tannins) and emissions of foliar VOCs. At the end of the growing season, trees were assessed for FHB larval presence and oviposition attempts. There were more larvae and oviposition attempts on trees stressed by herbicide application. Compared to other treatments, herbicide-stressed trees had greater nitrogen and total polyphenol concentrations. Greater nitrogen may play a role in the fitness of feeding larvae, and the greater polyphenol concentration may stimulate female oviposition in the herbicide stressed trees. Females may be able to locate the herbicide-stressed trees by using volatile cues such as increases in limonene, α-farnesene, (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT) and hexenyl acetate. [ABSTRACT FROM AUTHOR]

Despite the widespread empirical adoption of calcium hypochlorite (Ca(ClO)2) for sanitizing 3/16-inch tubing after the maple sap collection season, there remains a dearth of scientific data on its best practice and effectiveness. To address this gap, we cultivated microbial mass in tubing through continuous maple sap flow at 7 °C for 5 weeks in the lab. The tubing was sanitized with 200, 400, or 600 ppm Ca(ClO)2 and retained Ca(ClO)2 for either 10 min, 1 h, 7 days, or 6 weeks. Half of the tubing segments underwent microbial analysis, while the other half were stored for 6 weeks post-flushing of the Ca(ClO)2 to determine microbial survival/growth. The level and presence of the microbial load were determined, and the inner tubing surfaces were visualized using scanning electron microscopy (SEM). The initial microbial load in the tubing was approximately 4–5 log CFU/cm2. A 10-min and 1 h contact time with 200 ppm Ca(ClO)2, and a 10-min exposure to 400 ppm Ca(ClO)2, achieved reductions of 2.4–2.8 log for Pseudomonas spp., 1.6–2.5 log for mold and yeast, and 2.3–3.3 log for psychrotrophic microorganisms. Microorganisms were recovered from the enrichment process after retaining 200 ppm Ca(ClO)2 for 6 weeks, indicating insufficient inactivation. Consequently, the data suggests the use of at least 400 ppm Ca(ClO)2 for 1 day. The SEM images supported the microbial count results, offering valuable insights for educating maple syrup producers on optimal tubing sanitation practices. [ABSTRACT FROM AUTHOR]

Cotyledons play an important role in early seedling establishment. However, relative to primary leaves, cotyledons tend to have a different investment-on-return strategy. To detect the potential differences in the mass (M) versus area (A) scaling relationships between cotyledons and primary leaves in different light environments, a total of 75 Acer platanoides seedlings were sampled at an open site (n  = 52; light availability: 74 ± 5 %) and a shaded site (n  = 23; light availability: 4.2 ± 1.2 %). Reduced major axis regression protocols were used to fit the M versus A scaling relationships of primary leaves and cotyledons. The bootstrap percentile method was used to test the significance of the differences in the scaling exponents of M versus A between the two light environments. The scaling exponents of cotyledons at both two sites, as well as the primary leaves at the shade site, were greater than unity indicating 'diminishing returns', while the scaling exponent of primary leaves at the open site was smaller than unity indicating 'increasing returns'. The data collectively indicated light-dependent shifts in support investments and differences in the function of cotyledons and primary leaves. Average leaf structural traits displayed significant differences between the two light environments in accordance with the premium in enhancing photosynthetic capacity in high light and light interception in low light. Although the trait responses to light availability were similar for primary leaves and cotyledons, primary leaves were more responsive to light availability, indicating lower plasticity of cotyledons in response to light levels. These results advance our understanding of the roles of cotyledons and primary leaves in the life history of seedlings in different forest light environments. [ABSTRACT FROM AUTHOR]

This paper examined the surface morphology of maple and beech cut through by CO2 laser under different angles relative to the wood grain: 0°, 15°, 30°, 45°, 60°, 75°, and 90°. In the analysis, stylus measurements, stereo-microscopic images, and chemical changes were considered. Laser uncovers more wood anatomical details, with enhanced clarity, when the cutting transitions from along the grain to across the grain. This is particularly noticeable in the earlywood and is more pronounced in maple compared to beech. The first tissue of earlywood was deeply ablated by the laser, leading to a wavy anatomical pattern, which is more visible for higher angles of laser cutting in relation to the wood grain. The anatomical structure of beech was more affected by carbonization in comparison to maple and had a significantly higher core roughness, Rk. For both species, the worst surface roughness occurred when cutting at 15°. In maple, the laser caused more degradation of the polysaccharides compared to beech, and this impact was particularly noticeable parallel to the grain rather than at a 90° angle. The degradation of hemicelluloses occurred in parallel with more advanced cellulose degradation for beech compared to maple and for cutting along the grain compared to across the grain. Structural changes in lignin, such as condensation processes, were observed for both species. [ABSTRACT FROM AUTHOR]

The Pss exopolysaccharide (EPS) enhances the ability of the foodborne pathogen Listeria monocytogenes to colonize and persist on surfaces of fresh fruits and vegetables. Eradicating listeria within EPS-rich biofilms is challenging due to their increased tolerance to disinfectants, desiccation, and other stressors. Recently, we discovered that extracts of maple wood, including maple sap, are a potent source of antibiofilm agents. Maple lignans, such as nortrachelogenin- 8'-O-β-D-glucopyranoside and lariciresinol, were found to inhibit the formation of, and promote the dispersion of pre-formed L. monocytogenes EPS biofilms. However, the mechanism remained unknown. Here, we report that these lignans do not affect Pss EPS synthesis or degradation. Instead, they promote EPS detachment, likely by interfering with an unidentified lectin that keeps EPS attached to the cell surfaces. Furthermore, the maple lignans inhibit the activity of L. monocytogenes sortase A (SrtA) in vitro. SrtA is a transpeptidase that covalently anchors surface proteins, including the Pss-specific lectin, to the cell wall peptidoglycan. Consistent with this, deletion of the srtA gene results in Pss EPS detachment from listerial cells. We also identified several additional maple compounds, including epicatechin gallate, isoscopoletin, scopoletin, and abscisic acid, which inhibit L. monocytogenes SrtA activity in vitro and prevent biofilm formation. Molecular modelling indicates that, despite their structural diversity, these compounds preferentially bind to the SrtA active site. Since maple products are abundant and safe for consumption, our finding that they prevent biofilm formation in L. monocytogenes offers a viable source for protecting fresh produce from this foodborne pathogen. [ABSTRACT FROM AUTHOR]

In order to study the germination rule of Acer grosseri Pax seeds from different provenances, the germination test of Acer grosseri Pax from different provenances was carried out by temperature, storage method and storage time. The results showed that the germination rate of Acer grosseri Pax seeds was very low under 5 ℃ low temperature. With the increase of temperature, the germination rate of seeds from different provenances had significant difference; 4 ℃ low temperature wet sand storage can significantly improve the seed germination rate of Acer grosseri Pax, under the same storage conditions, there were significant differences in seed germination rate among different provenances, under different storage conditions, the germination rate of the seed was higher in Pinglu County, Shanxi Province, and lower in Taibai County, Shaanxi Province; wet sand storage at 4 ℃ for 80 days could significantly increase the seed germination rate of Acer grosseri Pax from different provences, the seed germination rate of Pinglu County of Shanxi Province, Gujiao City of Shanxi Province and Tongchuan City of Shaanxi Province were significantly different under different storage time conditions, but not at other provenances. [ABSTRACT FROM AUTHOR]

Introduction: Acer truncatum Bunge, belonging to the Acer genus in the Aceraceae family, is a commonly planted afforestation species across China, Japan, Korea, Europe, and North America. Renowned for its vibrant fall colors, it holds significant ecological and ornamental value. Methods: In this study, Acer truncatum 'Lihong' was used as the research object. Starting from the callus induction of explants, the embryogenic callus of Acer truncatum 'Lihong' was obtained by systematically optimizing the medium and culture conditions. Then, the candidate gene AtrGST894 screened by transcriptome sequencing was transformed into embryogenic callus by Agrobacterium-mediated transformation. The genetic transformation system of Acer truncatum 'Lihong' embryogenic callus was initially established by continuously adjusting the conditions of Agrobacterium tumefaciens infection receptor materials, thus laying amaterial foundation for the study of themolecular regulation mechanismof Acer truncatum'Lihong' leaf color, and also preparing for the later molecular improvement breeding of Acer truncatum. Therefore, this study has important theoretical and practical significance. Results: The results showed that the best medium for callus induction of Acer truncatum was 1/2MS+2 mg/L 2,4-D+0.3 mg/L 6-BA+0.5 mg/L NAA; The embryogenic callus induction medium of Acer truncatum was 1/2MS+3.0mg/L 6-BA+2.0mg/L TDZ+0.5mg/L IBA+0.1mg/L GA3; The proliferation medium of embryogenic callus of Acer truncatum was WPM+1.0mg/L TDZ+0.5mg/L IBA +0.1mg/L GA3+3mg/L 6-BA+1.0mg/L KT; The infection experiment of Agrobacterium tumefaciens on the embryogenic callus of Acer truncatum showed that the best antibacterial medium was WPM+30g/L sucrose+8g/L agar+0.5g/L acid-hydrolyzed casein+0.2mg/L KT+1.0 mg/L TDZ+0.5 mg/L IBA+0.1 mg/L GA3 +200mmol/L carboxybenzyl+200mg/L cephalosporin, and then WPM+30g/L sucrose+8g/L agar+0.5g/L acid-hydrolyzed casein+0.2mg/L KT+1.0 mg/L TDZ +0.5 mg/L IBA+0.1 mg/L GA3+300mmol/L carboxybenzyl+200mg/L cephalosporin+25mg/L hygromycin. Screening medium screening, The obtained embryogenic callus browning rate, pollution rate andmortality rate were the lowest, and maintained vigorous growth. Discussion: The embryogenic callus was used as the infection material to verify that we successfully transferred the target gene into the embryogenic callus, which means that the genetic transformation system of Acer truncatum embryogenic callus was partially completed, and the infection process could be effectively inhibited. Although there was partial browning, it could continue to proliferate. Therefore, in future experiments, the focus is still to continue to verify the optimal conditions for optimizing the genetic transformation of Acer truncatum embryogenic callus and to solve the problems of difficulty in embryonic callus germination. [ABSTRACT FROM AUTHOR]

Bark beetles (Curculionidae: Scolytinae) represent an important insect group including many significant pest species, but in some cases, the distribution and ecology of many bark beetles are still not well known. Maple bark beetle Scolytus koenigi Schyverew, 1890 is one of the mentioned group of species. The following study presents i) the first data of the occurrence of S. koenigi in Bohemia, ii) the first data of the species occurrence in an urban environment (large cities – Prague and Brno), iii) the distribution of the species in the Czech Republic since its first record (in 2013), and iv) new data about the bionomy of the species (i.e. a new host tree – Acer pseudoplatanus L. and refinement of the colonized substrate range diameter). [ABSTRACT FROM AUTHOR]

Tapping maple trees to produce maple syrup offers many benefits for producers. Since potential producers likely value some of these benefits more than others, communicators seeking to encourage more people to begin maple syrup production should use messaging that emphasizes the benefits that best resonate with potential producers. To test this strategy, known as emphasis message framing, we ran Facebook advertisements aimed at people living in Wisconsin, the fourth-leading U.S. state in annual maple syrup production, to test four message frames: building community, achieving food self-sufficiency, engaging in the lifestyle of working the land, and spending time in nature. Overall, the frame of working the land was the most effective in terms of link clicks and post reactions. However, among people ages 55+, who were more likely than younger Facebook users to engage with our advertisements, the food self-sufficiency frame received the most clicks while the nature frame received the most post reactions. In all age groups, women were more likely to click on our ads than men. These findings can be applied to future efforts to grow the number of small-scale maple syrup producers in Wisconsin and beyond. Additionally, our results underscore the importance of establishing a clear goal and segmenting audiences when designing social media campaigns. Our methods can serve as a blueprint for anyone seeking to empirically test the effectiveness of different message frames in public outreach related to agriculture or food systems. [ABSTRACT FROM AUTHOR]

Historically, tree sap has been used globally for medicinal purposes, in fermented beverages, and for syrup production. Maple tree sap is notably concentrated into syrup and is valued as a natural sweetener rich in phenolic compounds and minerals compared to refined sugar. Recently, syrups from other trees like black walnut (Juglans nigra) and sycamore (Platanus occidentalis) have gained popularity, yet their properties are not well understood scientifically. To address this gap, we collected sycamore, black walnut, and maple syrup samples and analyzed their physicochemical and functional properties. Our findings showed significant differences among the syrups in pH, browning intensity, and water activity (p < 0.05). Sycamore syrup had the highest total phenolic content, followed by black walnut and maple syrups. Both black walnut and sycamore syrups exhibited similar antioxidant activity, significantly higher than maple syrup (p < 0.05). High-resolution mass spectrometry identified 54 phenolic acids and 22 flavonoids in these syrups, including Acetylsalicylic acid, 3,5-Dihydroxybenzoic acid, and syringic acid, known for their antioxidant and anti-inflammatory properties. Additionally, sycamore syrups and most black walnut syrups displayed varying degrees of antimicrobial activity against Gram-positive and/or Gram-negative microorganisms. This study offers insights into the properties and potential health benefits of these specialty tree syrups. [ABSTRACT FROM AUTHOR]

A foundational concept in ecology is the positive relationship between habitat heterogeneity and species diversity. Epiphytes demonstrate microhabitat specialization to particular areas within a tree; thus, epiphyte communities are potentially influenced by the structural heterogeneity of host trees. We evaluated the relationship between structural features of Acer macrophyllum and epiphyte distributions and abundance in a temperate rainforest in Washington, USA. Epiphytes and structural features of three Acer macrophyllum trees were systematically surveyed using the point-intercept method from the base to the crown and on three branches for each tree. Rarefied species richness increased with structural richness. Species richness along the trunk differed significantly among types of structural features (i.e., broken branches, burls, holes, rivets, branches, and trunks); broken branches had the highest species richness and branches had the lowest, followed by trunks. Rarefied species richness increased with height and peaked at 12 m, but the relationship between structural diversity and height was not significant. The species that occurred on branches were different to those that occurred on trunks, and species composition varied significantly among trunk features. The high structural diversity in northern temperate rainforest trees influenced the fine-scale distribution of nonvascular epiphytes and may explain their coexistence in tree crowns. [ABSTRACT FROM AUTHOR]

The present study is focused on evaluating acaricidal activity and chemical compositions of Erigeron acer root, which was identified as a promising candidate among fifteen Mongolian plant extracts tested for acaricidal activity. The acaricidal effect was evaluated against Haemaphysalis longicornis, assessed for toxicity to normal human skin fibroblast, and analyzed for its chemical constituents. The acetone extract of E. acer root showed significant activity against H. longicornis, with a lethal concentration (LC50) of 5.31 mg/mL and low toxicity, evidenced by a cytotoxic concentration (CC50) of 267.00 µg/mL. Using liquid chromatography-tandem mass spectrometry and molecular networking, thirteen natural compounds were identified, including pyrrolidines, alkaloids, fatty acids, and flavonoids, highlighting the efficacy of E. acer root extract as an effective acaricide against H. longicornis and offering insights for developing new tick control solutions. [ABSTRACT FROM AUTHOR]

The current article discusses Sierpinski networks, which are fractal networks with certain applications in computer science, physics, and chemistry. These networks are typically used in complicated frameworks, fractals, and recursive assemblages. The results derived in this study are in mathematical and graphical format for particular classes of these networks of two distinct sorts with two invariants, K-Banhatti Sombor (KBSO) and Dharwad, along with their reduced forms. These results can facilitate the formation, scalability, and introduction of novel interconnection network topologies, chemical compounds, and VLSI processor circuits. The mathematical expressions employed in this research offer modeling insights and design guidelines to computer engineers. The derived simulation results demonstrate the optimal ranges for a certain network. The optimization assistant tool deployed in this work provides a single maximized value representing the maximum optimized network. These ranges can be put into service to dynamically establish a network according to the requirements of this paper. [ABSTRACT FROM AUTHOR]

Sixty years ago, Butcher (Butcher Math. Soc. 3, 185–201 1963) characterized a natural tabulation of the order conditions for Runge–Kutta methods of order p as an isomorphism from the set of rooted trees having up to p nodes and provided examples of explicit and implicit methods of several orders. Within a few years, Fehlberg (Fehlberg 1968) derived pairs of explicit methods of successive orders that could be implemented efficiently by using the difference of each pair of estimates to control the local error. Unfortunately, Fehlberg's pairs were deficient for quadrature problems. Subsequently, this author (Verner SIAM J. Numer. Anal. 15, 772–790 1978, Verner SIAM J. Numer. Anal. 16, 857–875 1979) derived parametric families of explicit Runge–Kutta pairs of increasing orders 6 to 9 that avoided this problem altogether. These, and most known explicit methods, have been derived by exploiting certain "simplifying conditions" suggested by Butcher (Butcher Math. Soc. 3, 185–201 1963, Butcher 1987 [pp. 194 f.]) that imposed constraints on subsets of the coefficients and thereby simplified the solution of the order conditions for moderate to high-order methods. "RK-Test-21", a MAPLE program developed recently by Butcher (Butcher 2021), was applied to derive known 13-stage pairs of orders 7 and 8. Unexpectedly, results of this application revealed the existence of some previously unknown pairs—i.e., some with the correct orders that satisfied most, but not all, of the previously known simplifying conditions. This present study develops formulas for directly computing exact coefficients of these new pairs together with others lying within this new parametric family of (13,7-8) pairs. While the best of these new pairs falls short of the best of pairs already known, the properties discovered might be utilized to precisely characterize recently reported higher-order methods found using other approaches by Khashin (Khashin 2009) and Zhang (Zhang 2019) and possibly lead to finding other Runge–Kutta and related yet unknown methods. [ABSTRACT FROM AUTHOR]

Determining the role of trees in the water cycle and their impact on soil moisture and atmospheric humidity is crucial. This study aimed to investigate the patterns of leaf transpiration in Quercus robur and Acer campestre in a maple-oak forest under varying water supply conditions. The research was conducted in the lower third of the lower third of the north-facing slope and the middle third of the south-facing slope in the Viiskova ravine. A silvicultural and taxation survey of model trees was conducted on both sample plots, where the plantations are moderately dense. The diurnal course of transpiration patterns of these deciduous species was studied throughout the vegetation period. This physiological process reached its highest values in both species on the north-facing slope during the summer months, especially in Quercus robur. On the southfacing slope, in May and June, the average daily transpiration values in both species were almost indistinguishable. During the remaining months of the vegetation period, the intensity of water evaporation by Quercus robur leaves was statistically higher than that of Acer campestre. It was established that on the south-facing slope, under more arid conditions, this process is less active. This pertains to the daily transpiration loss of water by leaves per unit of their mass, monthly transpiration, and the intensity of this process per tree. The difference between the results of water loss by the leaves of a single Quercus robur and Acer campestre tree is significant and is attributed to the lower transpiration rate of Acer campestre, except in May and June under xerophytic conditions, as well as the smaller leaf mass of this species. Both Quercus robur and Acer campestre are hydrostable medium-transpiring species. The maple forest on the north-facing slope evaporates 30.6% more moisture per 1 ha per vegetation period than on the south-facing slope. The results obtained indicate that Acer campestre in a maple-oak forest, under fresh and dry forest-growing conditions, does not pose a significant competition for moisture for Quercus robur when they grow together. The results obtained can be used to develop effective forest management strategies in maple-oak forest. [ABSTRACT FROM AUTHOR]

We have recently introduced MAPLE (MAximum Parsimonious Likelihood Estimation), a new pandemic-scale phylogenetic inference method exclusively designed for genomic epidemiology. In response to the need for enhancing MAPLE's performance and scalability, here we present two key components: (i) CMAPLE software, a highly optimized C++ reimplementation of MAPLE with many new features and advancements, and (ii) CMAPLE library, a suite of application programming interfaces to facilitate the integration of the CMAPLE algorithm into existing phylogenetic inference packages. Notably, we have successfully integrated CMAPLE into the widely used IQ-TREE 2 software, enabling its rapid adoption in the scientific community. These advancements serve as a vital step toward better preparedness for future pandemics, offering researchers powerful tools for large-scale pathogen genomic analysis. [ABSTRACT FROM AUTHOR]

The formation of a single species, recalcitrant understory vegetation layer can limit tree regeneration and, in the long term, modify the composition of forests. Few studies have investigated how recalcitrant vegetation influences competition for water resources although the formation of a dense understory is likely to modify the forest water balance. In eastern North American hardwood forests, the development of a dense understory layer of American beech (Fagus grandifolia) has been observed in stands dominated by sugar maple (Acer saccharum), a phenomenon that shares many characteristics associated with recalcitrant vegetation. Given that water availability is generally negatively correlated with stand density, we hypothesized that the formation of a dense understory beech layer increased competition for water resources, thus leading to reduced water use by sugar maple trees in beech‐dominated stands. Using thermal dissipation sensors, we measured sap flux density (Fd) of two sugar maple trees at three beech‐dominated sites and three control sites. During the growing season, Fd of sugar maple trees was significantly larger at beech‐dominated sites compared to control sites, indicating a greater rate of water use by sugar maples in stands with a dense understory beech layer. We provide two hypotheses to explain our results at the tree scale: (i) reduced cover by forest floor vegetation could limit transpiration by this layer, thus allowing increased water availability to supply transpiration by overstory trees, or (ii) increased tree transpiration rate could be a mechanism to satisfy nutrient requirements in beech‐dominated stands often associated with lower soil fertility. [ABSTRACT FROM AUTHOR]

The aim of the present study was to elucidate the effects of soil compaction on the seedlings of two species of deciduous (Acer velutinum and Alnus subcordata) and evergreen trees (Pinus eldarica and Pinus nigra) in terms of above- and below-ground morphology in a greenhouse. Six soil compaction levels were applied: the lowest intensity (control), very low, low, moderate, heavy, and very heavy. The results showed that there were different effects according to the species. These effects were on lateral root length, stem diameter, leaf dry biomass, SSL (specific stem length), SRL (specific root length), LMR (leaf mass ratio), RMR (root mass ratio), SMR (stem mass ratio), and R/S (root-to-shoot ratio). The results showed that soil penetration resistance (SPR) had a significant effect on seedling variables such as lateral root length, stem diameter, leaf dry biomass, and SRL (p < 0.05). A. velutinum seedlings have the highest values of growth variables compared to three other species, followed by A. subcordata seedlings. The two evergreen species, Pinus eldarica and Pinus nigra, have the lowest values of these growth variables. It is worth noting that we found that deciduous species had enhanced growth up to a moderate compaction level (1.3 MPa), while the growth decreased at an SPR that was higher than this value. [ABSTRACT FROM AUTHOR]

The photosynthesis and chlorophyll content are fundamental to understanding ecological processes in forest ecosystems, providing valuable clues to the health and functioning of these complex systems. The study of photosynthetic rates and chlorophyll content in five different tree species (Carpinus betulus, Fraxinus excelsior, Robinia pseudoacacia, Acer campestre and Acer pseudoplatanus) conducted in two different locations, namely in the Iron Gates Natural Park in Moldova Nouă (PNPF) and in Timișoara, brings to the fore a detailed analysis of the adaptations and responses of vegetation to environmental variability. Across the whole study, Acer pseudoplatanus revealed a significantly higher value of chlorophyll content, followed by Robinia pseudoacacia and Carpinus betulus with similar values and Acer campestre and Fraxinus excelsior with the lowest values, respectively. Acer campestre had a significantly higher photosynthesis rate than the other species, while Acer pseudoplatanus had the lowest values in both locations. [ABSTRACT FROM AUTHOR]