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Abstract Fire events in South America are becoming more extensive and frequent as climate extremes and human pressures increase, and even repeatedly occurring in some areas within decades. However, the relationship between recurring fires and vegetation dynamics remains unclear. Here, we extracted the number of fire occurrences using burned area satellite product and analysed the relationship between recurring fires and vegetation dynamics with remote sensing land use and vegetation index datasets in South America. We show that approximately 1.39 × 106 km2 of burnt area has experienced recurring fires during 2001–2020. More than half of burnt area of recurring fires occurred in savannahs with remaining burnt area in grasslands, forests and croplands. Although forests tended to be less susceptible to recurring fires among all vegetation types, their coverage loss with recurring fires was the greatest. The greater proportion of forest conversion to croplands concurred with more recurring fires. Conversely, the coverage of croplands and grasslands gained the most with recurring fires. In the areas without vegetation conversion, more frequent recurring fires further suppressed canopy greenness and density, even in fire‐adapted savannahs and grasslands. Our results suggest that recurring fires and land use change are generally coincident, reflecting the intense pressure of human activities on natural vegetation in South America. Thus, coordinated efforts on vegetation conservation and sustainable management of human‐induced burning in the region are urgently needed.

Abstract Antarctic moss beds are sensitive to climatic conditions, and both their survival and community composition are particularly influenced by the availability of liquid water over summer. As Antarctic regions increasingly face climate pressures (e.g., changing hydrology and heat waves), advancing capabilities to efficiently and non‐destructively monitor water content in moss communities becomes a key research priority. Because of the complexity induced by multiple micro‐climatic drivers and its fragility, tracking the evolution and responses of moss bed moisture requires monitoring methods that are non‐intrusive, efficient, and spatially significant, such as the use of unoccupied aerial systems (UAS). In this study, we combine a multi‐species drying laboratory experiment with short‐wave infrared (SWIR) spectroscopy analyses to first develop a Random Forest regression Model (RFM) capable of predicting Antarctic moss turf water content (~5% error). The RFM was then applied to UAS‐borne SWIR imaging data (900–1700 nm,

Abstract Urban heat stress is a critical issue, particularly in cities where dense infrastructure and limited green space exacerbate temperature extremes. This study investigates the impact of greenery (EVI2), canopy cover (CC), impervious cover (IC), and water bodies on heat index in Chicago using high‐resolution data from the Heat Watch campaign. We find that EVI2, CC and proximity to water body significantly reduce heat while IC increases heat, particularly in the afternoon when solar radiation is intense. Additionally, the effective radius that land cover impacts heat is smaller in the afternoon. The combined effect analysis indicates that enhancing total greenness, not just canopy cover, is the most effective strategy to reduce heat. This study underscores the importance of strategic vegetation management, highlighting the critical role of integrated approaches in reducing urban heat.

Abstract As a key region supplementing China's limited croplands, Northwest China has undergone rapid cropland expansion over the past decades to satisfy rising food demand from population growth and socio‐economic development. Although cropland expansion may overconsume local water resources in general, in Northwest China, increased precipitation and enhanced glacier melt have increased the water available for croplands. Counterintuitively, the enhanced evapotranspiration (ET) resulting from this cropland expansion could benefit remote ecologically vulnerable natural vegetation through atmospheric moisture recycling. In this study, we used a moisture tracking model to quantify contributions of croplands and cropland expansion to local precipitation and the consequent precipitation supply to natural vegetation in Northwest China. We found that the croplands contributed 27.69 billion m3/year (2.13%) of regional total precipitation and supplied 17.30 billion m3/year (2.39%) of precipitation over natural vegetation, and the cropland expansion resulted in a net increase of 80.25 million m3/year (1.07% of the total increase) in regional precipitation and 36.23 million m3/year (4.56% of the total increase) in precipitation supply for natural vegetation. Among different types of natural vegetation, grasslands received the most precipitation supply due to its vast area, followed by forests and shrublands. The more arid regions experienced not only faster rates of cropland expansion but also obtained a greater increase in regional precipitation and precipitation supply to natural vegetation. Our study quantifies the ecological impacts of cropland expansion through moisture recycling in Northwest China. This shows the complexities of water competition between agricultural development and ecological conservation in drylands and elsewhere.

Abstract Vegetation is a major contributor of terrestrial evaporation and influences subsequent precipitation over land. Studies suggest that forests are crucial for moisture recycling, although the specific contribution of different vegetation to precipitation remains unclear. Using a moisture recycling approach, we investigate the contribution of transpiration from trees and non‐tree vegetation to precipitation over Africa. We use precipitation source regions from simulated atmospheric moisture trajectories, constrained by observation‐based evaporation and precipitation products, and fractional vegetation cover data. Our findings show that trees provide a higher flux to precipitation (∼777 mm year−1) than non‐tree vegetation (∼342 mm year−1). However, considering the smaller spatial extent of trees compared to non‐tree vegetation, precipitation in most watersheds effectively depends more on the latter. Overall, non‐tree vegetation appears equally important as trees in terms of volumetric contributions to precipitation, and deserves attention in further research, considering ongoing land use changes that affect the continental water cycle.

Abstract Permafrost influences 25% of land in the Northern Hemisphere, where it stabilizes the ground beneath communities and infrastructure and sequesters carbon. However, the coevolution of permafrost, river dynamics, and vegetation in Arctic environments remains poorly understood. As rivers meander, they erode the floodplain at cutbanks and build new land through bar deposition, creating sequences of landforms with distinct formation ages. Here we mapped these sequences along the Koyukuk River floodplain, Alaska, analyzing permafrost occurrence, and landform and vegetation types. We used radiocarbon and optically stimulated luminescence (OSL) dating to develop a floodplain age map. Deposit ages ranged from modern to 10 ka, with more younger deposits near the modern channel. Permafrost rapidly reached 50% areal extent in all deposits older than 200 years then gradually increased up to ∼85% extent for deposits greater than 4 Kyr old. Permafrost extent correlated with increases in black spruce and wetland abundance, as well as increases in permafrost extent within wetland, and shrub and scrub vegetation classes. We developed an inverse model to constrain permafrost formation rate as a function of air temperature. Permafrost extent initially increased by ∼25% per century, in pace with vegetation succession, before decelerating to

Abstract Global warming has intensified the intensity of compound drought‐hot extremes (CDHEs), posing more severe impacts on human societies and ecosystems than individual extremes. The vulnerability of global terrestrial ecosystems under CDHEs, along with its key influencing factors, remains poorly understood. Based on multiple remote sensing data, we construct a Vine Copula model to appraise vegetation vulnerability under CDHEs, and attribute it to climatic and biotic factors for five different vegetation types. High vulnerability is detected in central and southern regions of North America, eastern and southern regions of South America, Southern Africa, northern and western Europe, and northern and eastern Australia. The drier the climate, the higher will be the vulnerability. Furthermore, biodiversity and biomass are key biotic factors influencing the vulnerability of various vegetation types, such that ecosystems with richer biodiversity and higher biomass have lower vulnerability to CDHEs. The findings deepen understanding of terrestrial ecosystem response to CDHEs.

Key Clinical Message Percutaneous aspiration for debulking of vegetations in right‐sided infective endocarditis has been well‐described, however, this technique can be employed successfully for left‐sided vegetations in select high‐risk patients. Abstract We report a case of percutaneous aspiration of an aortic valve vegetation in a patient with prosthetic valve endocarditis. This novel approach was selected after patient declined surgical intervention for an enlarging vegetation despite antibiotic therapy. The procedure was successful, resulting in the complete removal of solid vegetation without complications.

Abstract The Mediterranean peninsulas host rich assemblages of lizards, but little is known about the factors that limit their habitat use on large spatial scales. In this study, we investigated the variation in habitat use of 29 species of lacertid lizards on the Iberian and Italian peninsulas and the transitional region of southeastern France. We investigated whether the types of habitat used were phylogenetically determined or, in contrast, were more influenced by spatial or climatic effects. We characterized the vegetal composition of 483 habitats used by lacertids and estimated the contribution of each component to habitat variability using distance‐based redundancy analysis. We showed that overall turnover patterns were determined similarly in both peninsulas, despite differences in the composition of the lacertid assemblages. The aridity‐related component dominated over the phylogenetic one, which has a weak influence in both regions. The species showed different turnover patterns, being low in those present in cold alpine habitats and shrub‐steppe specialists. In some Iberian endemics, habitat turnover occurs within relatively homogeneous climatic bands. However, in the Italian species, habitat turnover has a comparatively stronger climatic component, suggesting lower climatic specialization. This study shows that species distributions across habitats provide information to assess community properties and can be applied to explore differences among faunal assemblages over large geographic areas. Our results provide evidence that beta diversity can play a key role in structuring patterns of habitat turnover.

Abstract Plant species richness is an important property of ecosystems that is altered by grazing. In a semiarid environment, we tested the hypotheses that (1) small‐scale herbaceous plant species richness declines linearly with increasing grazing intensity by large ungulates, (2) precipitation and percent sand interact with grazing intensity, and (3) response of herbaceous plant species richness to increasing intensity of ungulate grazing varies with patch productivity. During January–March 2012, we randomly allocated 50, 1.5‐m × 1.5‐m grazing exclosures within each of six 2500 ha study sites across South Texas, USA. We counted the number of herbaceous plant species and harvested vegetation in 0.25‐m2 plots within exclosures (ungrazed control plots) and in the grazed area outside the exclosures (grazed treatment plots) during October–November 2012–2019. We estimated percent use (grazing intensity) based on the difference in herbaceous plant standing crop between control plots and treatment plots. We selected the negative binomial regression model that best explained the relationship between grazing intensity and herbaceous plant species richness using the Schwarz‐Bayesian information criterion. After accounting for the positive effect of precipitation and percent sand on herbaceous plant species richness, species richness/0.25 m2 increased slightly from 0% to 30% grazing intensity and then declined with increasing grazing intensity. Linear and quadratic responses of herbaceous plant species richness to increasing grazing intensity were greater for the least productive patches (

Abstract Changes in vegetation in North America indicate Holocene shifts in the latitudinal temperature gradient along the western margin of the North Atlantic. Tree taxa such as oak (Quercus) and birch (Betula) experienced opposing directions of change across different latitudes consistent with changes in temperature gradient steepness. Pollen‐inferred temperatures from 34 sites quantify the gradient changes and reconstruct a long‐term northward steepening in summer and southward steepening in winter. From 4.8 to 3.8 ka, an oscillation in tree distributions interrupted the long‐term trends as a steep temperature gradient developed north of 43.5°N. The shift likely limited cold outbreaks to the south, producing anomalously high summer temperatures at 42–43.5°N, and enabling a northward expansion of oak forests. The forest and temperature gradient changes appear consistent with orbital and ice sheet forcing as well as millennial variability in the North Atlantic pressure field analogous to the North Atlantic Oscillation on interannual time scales.

Key Clinical Message Infective endocarditis should be considered in any febrile individual with acute onset neurological symptoms. If suspicion is high, a negative brain computed tomography does not virtually exclude embolism, and magnetic resonance imaging is warranted. Abstract A diagnosis of infective endocarditis (IE) is often delayed, particularly in those infected with unusual organisms. Hereby, we report a case of a female patient presented with dysarthria, confusion, and altered mental status after being treated for Escherichia coli bacteremia. Computed tomography of the brain was unrevealing; however, scattered embolic phenomena were visualized on magnetic resonance imaging (MRI). The case underscores the importance of clinical awareness, particularly in the setting of unusual microorganisms, and the role of brain MRI in the diagnosis of IE.

Abstract Vegetation is an underutilized medium for environmental DNA (eDNA) sampling. eDNA methods leveraging water as a substrate exclude application to many terrestrial species. The use of eDNA to detect small mammals can complement current survey approaches (live capturing, track plating, and camera trapping) while reducing risks to the animals. The endangered New Mexico meadow jumping mouse (Zapus hudsonius luteus) is specialized to herbaceous riparian zones, making it an ideal candidate for developing a terrestrial eDNA detection method. We developed a species‐specific assay for quantitative real‐time PCR, then tested the long‐term persistence of jumping mouse eDNA on plant material using four herbaceous day nests collected three to six months after occupancy. We conducted a field trial using sterile cotton swabs at six locations along two occupied streams to evaluate our assay's capability to detect present‐day eDNA. Each of 60 swabs was used to swab a 0.50 m2 area along streamside transects that included vegetation such as forbs, grasses, and sedges. We also opportunistically swabbed plants (n = 9) following visual observation of jumping mice. We determined the limit of detection for both assays are fewer than eight copies per reaction. We detected eDNA in three of four nests. From field trial samples, we successfully detected the species from randomly swabbed vegetation (N = 3), and four of nine swabs from vegetation recently used by individuals. Further work is required to develop a robust survey method using this eDNA detection approach. Our study demonstrated that mammalian eDNA can persist on nest vegetation long after the animal was present, highlighting the promise of using eDNA from plants to detect rare or endangered terrestrial species.

Abstract The alpine treeline ecotone is expected to move upwards in elevation with global warming. Thus, mapping treeline ecotones is crucial in monitoring potential changes. Previous remote sensing studies have focused on the usage of satellites and aircrafts for mapping the treeline ecotone. However, treeline ecotones can be highly heterogenous, and thus the use of imagery with higher spatial resolution should be investigated. We evaluate the potential of using unmanned aerial vehicles (UAVs) for the collection of ultra‐high spatial resolution imagery for mapping treeline ecotone land covers. We acquired imagery and field reference data from 32 treeline ecotone sites along a 1100 km latitudinal gradient in Norway (60–69°N). Before classification, we performed a superpixel segmentation of the UAV‐derived orthomosaics and assigned land cover classes to segments: rock, water, snow, shadow, wetland, tree‐covered area and five classes within the ridge‐snowbed gradient. We calculated features providing spectral, textural, three‐dimensional vegetation structure, topographical and shape information for the classification. To evaluate the influence of acquisition time during the growing season and geographical variations, we performed four sets of classifications: global, seasonal‐based, geographical regional‐based and seasonal‐regional‐based. We found no differences in overall accuracy (OA) between the different classifications, and the global model with observations irrespective of data acquisition timing and geographical region had an OA of 73%. When accounting for similarities between closely related classes along the ridge‐snowbed gradient, the accuracy increased to 92.6%. We found spectral features related to visible, red‐edge and near‐infrared bands to be the most important to predict treeline ecotone land cover classes. Our results show that the use of UAVs is efficient in mapping treeline ecotones, and that data can be acquired irrespective of timing within a growing season and geographical region to get accurate land cover maps. This can overcome constraints of a short field‐season or low‐resolution remote sensing data.

Abstract Unmanned Aerial Vehicles (UAVs) offer new opportunities for accurate, repeatable vegetation assessments, which are needed to adaptively manage restored habitat. We used UAVs, ground surveys, and satellite imagery to evaluate vegetation metrics for three riparian restoration sites along the Colorado River in Mexico and we compared the data accuracy and efficiency (cost and time requirements) between the three methods. We used an off‐the‐shelf UAV coupled with a multispectral sensor to determine Normalized Difference Vegetation Index (NDVI) and vegetation cover. We were unable to accurately classify vegetation by individual species, but by grouping riparian species of interest (cottonwood‐willow, mesquite, shrubs), we achieved high overall model accuracies of 87–96% across sites (Kappa = 0.82–0.95). Producer’s and user’s accuracies were moderate to high for target vegetation classes (69–100%). UAV and ground‐survey vegetation percent cover differed due to differences in methodologies (UAVs measure aerial cover; ground surveys measure foliar cover) and sources of error for each method. Correlations between UAV and ground survey vegetation cover were moderate (rs(90) = 0.24–0.58, p

Abstract The origin of Dahomey Gap (DG) flora is one of the central biogeographical questions in sub‐Saharan, which has been addressed in several studies. However, floristic evidence based on representative samples from the DG seems to be lacking in the scientific debate. The present study was conducted to fill this gap. Specifically, we assessed Togolese mountain riparian forests as minor forest refugia, examined their contribution to larger sub‐Saharan forest refugia, and discussed the significance of these findings for biogeography and biodiversity conservation. Southwest Togo, West Africa, and sub‐Saharan Upper Guinea Region Floristic data were collected in riparian forests through an intensive botanical inventory (n = 198; 50 × 10 m2). A comparative analysis was performed based on the floristic evidence related to forest refuges. The results showed significantly high species richness (868 species) and a high gamma and beta diversity associated with spatial turnover patterns. They also showed a high affinity between the study forests and large sub‐Saharan forest refugia. Riparian forests share about 60% of their current species richness with large sub‐Saharan forest refugia and contained refuge bio‐indicator species. The floristic evidence, consistent with those of other studies, suggests that Togolese mountains would have very ancient origins and have experienced paleoclimatic events. The studied riparian would have served as refuges during recurrent climatic episodes. Our results support the minimal forest fragmentation hypothesis (network of refugia along rivers). However, they seem to be incompatible with the idea that the DG flora may be essentially a relic of the early Holocene. In sub‐Saharan Africa, where maintaining a vast area of natural forest is difficult due to human pressure, efforts to preserve maximum species diversity should include a focus on the conservation of minor forest refuges, particularly in sub‐humid mountain riparian zone.

Abstract The population of the Yellow‐breasted Bunting Emberiza aureola, a formerly widely distributed and abundant songbird of northern Eurasia, suffered a catastrophic decline and a strong range contraction between 1980 and 2013. There is evidence that the decline was driven by illegal trapping during migration, but potential contributions of other factors to the decline, such as land‐use change, have not yet been evaluated. Before the effects of land‐use change can be evaluated, a basic understanding of the ecological requirements of the species is needed. We therefore compared habitat use in ten remaining breeding regions across the range, from European Russia to Japan and the Russian Far East. We also assessed large‐scale variation in habitat parameters across the breeding range. We found large variation in habitat use, within and between populations. Differences were related to the cover and height of trees and shrubs at Yellow‐breasted Bunting territories. In many regions, Yellow‐breasted Buntings occupied early successional stages, including anthropogenic habitats characterized by mowing, grazing, or fire regimes. We found that the probability of presence can be best predicted with the cover of shrubs, herbs, and grasses. Highest probabilities were found at shrub cover values of 40%–70%. Differences in habitat use along a longitudinal gradient were small, but we found strong differences across latitudes, possibly related to habitat availability. We conclude that the remaining Yellow‐breasted Bunting populations are not limited to specific habitat types. Our results provide important baseline information to model the range‐wide distribution of this critically endangered species and to guide targeted conservation measures.

Abstract Quantifying the timing of vegetation phenology is critical for monitoring and modelling ecosystem responses to environmental change. Phenological processes have been studied from landscape to global scales using Earth observing satellite data, and at local scale by in situ surveys of individual plants. Now, data acquired from multi‐spectral sensors on drone platforms provide flexible opportunities for monitoring phenology from individual plants to small ecosystem scales efficiently, allowing community and species level information to be derived. We captured a time‐series of drone‐acquired normalized difference vegetation index (NDVI) data with a multi‐spectral sensor (Parrot Sequoia, (Parrot, France)) over a highly heterogeneous ecosystem in Cornwall, UK, during a period of spring green‐up. We monitored NDVI trajectories at the individual crown and species’ level. For deciduous crowns, we derived metrics representative of spring phenological stages: Start‐of‐spring (SOS), middle‐of‐spring green‐up (MOG) and start‐of‐peak greenness (SOP) using a logistic function. While the exact timing of SOS, MOG and SOP appeared susceptible to understorey effects and saturation of the NDVI, relative timing of green‐up for a subset of species was plausible in relation to phenological observations from an extended geographic region and in situ plant area index (PAI) measurements. In evergreen vegetation (Pinus spp.) subtle changes were also detected through the growing season. The impact of illumination differences was analysed for image pairs during leaf‐off and leaf‐on conditions. While significant, these effects were small (mean absolute NDVI deviation of up to 0.034 for leaf‐off, 0.013 for leaf‐on conditions), meaning that data captured under both constant direct and diffuse irradiance conditions can be used together and that cloudy conditions should not lead to data gaps. We conclude that the capability of drone‐mounted multi‐spectral instruments for spatio‐temporal characterization of crown‐level phenology shows great promise for improving the understanding of intra‐ and inter‐species differences in strategy, and offers an efficient means of doing so over areas of a few hectares.

Abstract Erosion of landscapes underlaid by permafrost can transform sediment and nutrient fluxes, surface and subsurface hydrology, soil properties, and rates of permafrost thaw, thus changing ecosystems and carbon emissions in high latitude regions with potential implications for global climate. However, future rates of erosion and sediment transport are difficult to predict as they depend on complex interactions between climatic and environmental parameters such as temperature, precipitation, permafrost, vegetation, wildfires, and hydrology. Thus, despite the potential influence of erosion on the future of the Arctic and global systems, the relations between erosion‐rate and these parameters, as well as their relative importance, remain largely unquantified. Here we quantify these relations based on a sedimentary record from Burial Lake, Alaska, one of the richest datasets of Arctic lake deposits. We apply a set of bi‐ and multi‐variate techniques to explore the association between the flux of terrigenous sediments into the lake (a proxy for erosion‐rate) and a variety of biogeochemical sedimentary proxies for paleoclimatic and environmental conditions over the past 25 cal ka BP. Our results show that erosion‐rate is most strongly associated with temperature and vegetation proxies, and that erosion‐rate decreases with increased temperature, pollen‐counts, and abundance of pollen from shrubs and trees. Other proxies, such as those associated with fire frequency, aeolian dust supply, mass wasting and hydrologic conditions, play a secondary role. The marginal effects of the sedimentary‐proxies on erosion‐rate are often threshold dependent, highlighting the potential for strong non‐linear changes in erosion in response to future changes in Arctic conditions.

Abstract Fire regimes are influenced by both exogenous drivers (e.g., increases in atmospheric CO2 and climate change) and endogenous drivers (e.g., vegetation and soil/litter moisture), which constrain fuel loads and fuel aridity. Herein, we identified how exogenous and endogenous drivers can interact to affect fuels and fire regimes in a semiarid watershed in the inland northwestern United States throughout the 21st century. We used a coupled ecohydrologic and fire regime model to examine how climate change and CO2 scenarios influence fire regimes. In this semiarid watershed, we found an increase in burned area and burn probability in the mid‐21st century (2040s) as the CO2 fertilization effect on vegetation productivity outstripped the effects of climate change‐induced fuel decreases, resulting in greater fuel loading. However, by the late‐21st century (2070s), climatic warming dominated over CO2 fertilization, thus reducing fuel loading and burned area. Fire regimes were shown to shift from flammability‐ to fuel‐limited or become increasingly fuel‐limited in response to climate change. We identified a metric to identify when fire regimes shift from flammability‐ to fuel‐limited: the ratio of the change in fuel loading to the change in its aridity. The threshold value for which this metric indicates a flammability versus fuel‐limited regime differed between grasses and woody species but remained stationary over time. Our results suggest that identifying these thresholds in other systems requires narrowing uncertainty in exogenous drivers, such as future precipitation patterns and CO2 effects on vegetation.

Abstract The observed spatial and temporal dynamics in landscape and ecosystem resources are the net effects of natural processes and management activities. Monitoring the impact that humans have on these resources requires that these two sources of variability be partitioned, removing the natural variability to reveal variability due to management activities. Here, we present Compere, a relative benchmarking framework for monitoring the management‐driven impacts on ecosystem resources. The framework identifies locations in a region that share similar biophysical properties to a target location. Taking an attribute of interest, it then compares the value of the target location with those of all its biophysically equivalent locations, with any differences being attributed to variations in management. We provide an example application of Compere, using satellite‐derived vegetation cover data to examine the impact of hydrocarbon extraction activities on land condition (as described by vegetation cover) across the 490,000‐km2 Cooper Creek region in arid central Australia. Validation was performed by comparing land condition estimates to known disturbance patterns across the region. We found that the establishment of well sites was associated with between 12% and 41% decreases in land condition but that condition recovered to original levels by 6 years after establishment. We also found that fires had much larger and longer lasting effects on land condition across these landscapes, indicating that mining‐related activities that change fire patterns are likely to affect land condition most. Compere is a generic, flexible framework, providing a new capability for monitoring management impacts on multiple types of ecosystem resources.

Abstract Background There have been a few cases of echogenic cardiac implantable electric device (CIED) lead‐associated oscillating intracardiac masses (ICMs) in leads imaged by echocardiography. The histological properties of ICMs could help clarify the etiological diagnosis. Although there is extensive literature on mass size, the histological properties of such masses have not been characterized. The aim of this research was to clarify the histological features of oscillating ICMs in CIED patients. Methods Preoperative echocardiography was performed in all candidates for CIED removal. In the patients with ICMs, specimens were obtained by 3 methods: direct tissue collection during open‐heart surgery; tissue collection together with the CIED lead during transvenous extraction; and tissue collection by catheter vacuum during transvenous CIED removal. A standard histopathological examination of ICM tissue was performed. Results A total of 106 patients underwent lead removal in our institute (April 2009‐March 2018); 14 patients had an ICM (13.2%), and 7 specimens were obtained in patients with CIED lead‐related ICM. Following histological examination, 2 types of ICM were identified: one mainly composed of thickened endocardium (EN type; 3 patients), and the other mainly an aggregate of inflammatory cells as a neutrophil cell (NC type; 4 patients). Conclusions Two histological types of intracardiac masses, including a thickened endocardium type and a neutrophil cell type, were identified. These classifications might help make an accurate histological diagnosis of lead‐associated intracardiac masses.

Abstract Plants, especially trees, provide ecological functions but may harm the flood conveyance efficiency of rivers. Understanding the impacts of tree heights, tree areas, and tree locations on flood levels is crucial for floodplain management. This study aims to present a methodology to improve the performance of hydrodynamic modeling by considering plant resistance with the goal of analyzing flood risk reduction strategies that support ecological conservation enhancement. An unmanned aerial vehicle was used to collect floodplain topography, landcover, and tree characteristic data. A modified maximum likelihood classification scheme was developed by incorporating the tree height information to improve the landcover classification. The water‐blocking effect of trees, which represents the reduced flood conveyance area, was investigated by establishing tree obstructions in hydrodynamic models. Two hydrodynamic models were established with different tree obstruction setups and Manning's n values, including blocked obstructions (BOs) and conventional high n‐values (Adj‐n). Among the model setups, the Manning's n values of the trees remained the same as that of the soil in the BO model, in which trees were modeled as blocking obstructions. The n‐values of trees were determined to be 0.022 in the BO model and refined to 0.055 in the Adj‐n model after the model calibration and verification processes. The results indicated that the simulated flood levels of the BO model were very similar to those of the Adj‐n model. The NSE values were 0.98 and 0.97 in the simulations of two historical typhoon events, indicating that the BO model could obtain reliable predictions without altering the n‐values. The verified BO model was used to evaluate the degrees of influence of tree heights, tree coverage areas, and tree locations on flood levels. Several nature‐based solutions were proposed to analyze the tradeoffs between reducing flood prevention and enhancing wetland restoration using the verified BO model, suggesting a win–win strategy for natural river management.

Abstract Perimyocarditis should be considered in patients with endocarditis not improving with conventional therapy and without typical valvular abnormalities. Vegetations can be sited anywhere in the atrium or ventricle and exhibit multiple shapes.

Abstract Rapid climate change at high latitudes is projected to increase wildfire extent in tundra ecosystems by up to fivefold by the end of the century. Tundra wildfire could alter terrestrial silica (SiO2) cycling by restructuring surface vegetation and by deepening the seasonally thawed active layer. These changes could influence the availability of silica in terrestrial permafrost ecosystems and alter lateral exports to downstream marine waters, where silica is often a limiting nutrient. In this context, we investigated the effects of the largest Arctic tundra fire in recent times on plant and peat amorphous silica content and dissolved silica concentration in streams. Ten years after the fire, vegetation in burned areas had 73% more silica in aboveground biomass compared to adjacent, unburned areas. This increase in plant silica was attributable to significantly higher plant silica concentration in bryophytes and increased prevalence of silica‐rich gramminoids in burned areas. Tundra fire redistributed peat silica, with burned areas containing significantly higher amorphous silica concentrations in the O‐layer, but 29% less silica in peat overall due to shallower peat depth post burn. Despite these dramatic differences in terrestrial silica dynamics, dissolved silica concentration in tributaries draining burned catchments did not differ from unburned catchments, potentially due to the increased uptake by terrestrial vegetation. Together, these results suggest that tundra wildfire enhances terrestrial availability of silica via permafrost degradation and associated weathering, but that changes in lateral silica export may depend on vegetation uptake during the first decade of postwildfire succession.

Abstract Exacerbated inundations and saltwater intrusions due to sea‐level rise can significantly alter the ecology of low‐lying coastal drylands by affecting their nutrient cycling and productivity. During the present study, controls on production and consumption of nitrogen in soils of semiarid tropical climate with different levels of vegetation–salinity–moisture condition were investigated using 15N isotope dilution experiments. For this purpose, soils were collected from five land types including two in salt flat and one each in grassland (GL), wetland (WL), and an agricultural field. Soils with no vegetation, high salinity, and high moisture (salt flats) showed significant decline in gross production of nitrogen (mineralization rate: 0.21 ± 0.10 mg N·kg−1·d−1; nitrification rate: 0.27 ± 0.17 mg N·kg−1·d−1) compared to soils with vegetation, low salinity, and low moisture (GL, WL, and agricultural) (mineralization rate: 2.47 ± 1.74 mg N·kg−1·d−1; nitrification rate: 1.43 ± 1.30 mg N·kg−1·d−1). Backward stepwise regression analysis of the results indicated salinity to be the most important factor controlling nitrogen transformation rates. It is likely that soils undergoing frequent seawater exposure or excessive evaporation may experience slowdown in nitrogen cycling due to salinization leading to reduced nutrient production and consumption. Due to climate change, the areal extent of coastal drylands undergoing such decline in nutrient production is likely to increase, eventually leading to loss of productivity and desertification.

Abstract Indicator species need context to perform optimally for conservation purposes. If indicator potential is context‐dependent, then indicators should improve with increasing spatial‐environmental stratification. We tested this hypothesis by hierarchically stratifying a species combinations matrix (plants and wetlands) using regionalization and site typology and analyzing class specificity and occupancy rate for indicators shared across strata. Performance of indicators collectively improved with increased sample stratification providing greater spatial‐environmental context. Carefully considered sample classification schemes could strengthen the value of indicator species for monitoring biodiversity loss, environmental change, and management progress. However, the better accuracy of context‐specific indicators will have to be weighed against the practical need for fewer broad‐based indicators.

Abstract Climate change is predicted to impact ecosystems through altered precipitation (PPT) regimes. In the Chihuahuan Desert, multiyear wet and dry periods and extreme PPT pulses are the most influential climatic events for vegetation. Vegetation responses are most frequently studied locally, and regional responses are often unclear. We present an approach to quantify correlation of PPT and vegetation responses (as Normalized Difference Vegetation Index [NDVI]) at the Jornada ARS‐LTER site (JRN; 550 km2 area) and the surrounding dryland region (from 0 to 500 km distance; 400,000 km2 study area) as a way to understand regional similarity to locally observed patterns. We focused on fluctuating wet and dry years, multiyear wet or dry periods of 3–4 yr, and multiyear wet periods that contained one or more extreme high PPT pulses or extreme low rainfall. In all but extreme high PPT years, JRN PPT was highly correlated (r > 0.9) to PPT across the regional study area (0–500 km distance; high correlation from 25th to 75th percentiles) and was highly correlated across a greater PPT range subregionally (0–200 km distance; high correlation from 10th to 90th percentiles). In contrast, the statistical distribution of JRN NDVI was less similar to that of regional NDVI. Yet, local‐regional NDVI similarity increased during multiyear periods to a maximum of >90% similarity for 10th–90th percentiles in a number of years. Thus, local‐regional heterogeneity in PPT and vegetation responses is reduced in both multiyear wet and dry periods, with the largest changes in climatic forcing and responses during multiyear wet periods. These wet and dry events support greater similarity between local‐regional PPT and vegetation response patterns. We conclude that site‐based research on multiyear periods can be extended to anticipate larger regional responses, and illustrate the opportunity to enhance understanding of future PPT change through increased focus on multiyear periods.

Vegetation chlorophyll content is very important for monitoring the growth and health status of vegetation. Remote sensing of chlorophyll content holds an important potential for evaluating crop growth status and diseases and insects. The both units can represent the chlorophyll content of leaves, but there are some differences between them. The former reflects the proportion of chlorophyll in the leaf components, while the latter displays the weight of chlorophyll in the unit leaf area. Combining ten representative hyperspectral vegetation indices, the effect of measurement units on estimating crop leaf chlorophyll content was studied with winter wheat and summer corn leaf chlorophyll content data and leaf reflectance data. First, the relationships between leaf chlorophyll content and the ten selected hyperspectral vegetation indices were analyzed. Second, the estimating models of leaf chlorophyll were built. Finally, the accuracies of estimating models were also assessed based on the validating data. The results show that: (i) due to chlorophyll absorption effect at visible bands, vegetation indices were highly correlated with chlorophyll content of crop leaves and it is feasible to estimate chlorophyll with vegetation index, for example, the relative errors for the estimating model based on MERIS Terrestrial Chlorophyll Index

Background Previous studies have documented the cardiometabolic health benefits of plant‐based diets; however, these studies were conducted in selected study populations that had narrow generalizability. Methods and Results We used data from a community‐based cohort of middle‐aged adults (n=12 168) in the ARIC (Atherosclerosis Risk in Communities) study who were followed up from 1987 through 2016. Participants’ diet was classified using 4 diet indexes. In the overall plant‐based diet index and provegetarian diet index, higher intakes of all or selected plant foods received higher scores; in the healthy plant‐based diet index, higher intakes of only the healthy plant foods received higher scores; in the less healthy plant‐based diet index, higher intakes of only the less healthy plant foods received higher scores. In all indexes, higher intakes of animal foods received lower scores. Results from Cox proportional hazards models showed that participants in the highest versus lowest quintile for adherence to overall plant‐based diet index or provegetarian diet had a 16%, 31% to 32%, and 18% to 25% lower risk of cardiovascular disease, cardiovascular disease mortality, and all‐cause mortality, respectively, after adjusting for important confounders (all P

Taking into account the respective advantages of synthetic aperture radar (SAR) data and optical data in obtaining object information, this article presents a method for retrieval of soil moisture in grassland based on multi-source data (SAR data, optical data and measured data). First of all, optical data is used to classify the grassland area, and then the SAR data is used to obtain the backscattering coefficient of the grassland area. Finally, the soil moisture under the vegetation cover is obtained through the water-cloud model and the microwave backscatter model. The soil moisture in grassland is retrieved and the retrieval results are compared and validated using measured data. The results showed that the suggested method has better classification precision for complex terrain with densely overlapping scattering mechanisms. This method also uses the measured data to correct the soil moisture, which greatly improves the precision of the results.

The frequent forest fires become a serious threat to the performance of transmission lines’ external insulation, and large quantities of smoke (carbon black) and flying ashes are produced during the combustion of vegetation, reducing the dielectric strength of the air gap drastically. In order to study the effect of the typical vegetation ashes on the discharge characteristics of conductor-plane air gap, experimental studies were carried out with vegetation fire simulation test platform in this study, and typical vegetation ashes of thatch, straw and fir branch were collected. The simulation model was built to analyse the influence mechanism of multiple particles on the breakdown characteristics. It shows that the existence of particles make the electric field distribution between conductor and plane non-uniform, the maximum electric field strength near the elongated particle is 10.2 times as much as the background electric field, and the maximum electric field strength of the gap increases by about 55.7%, when the length of the elongated particle changing from 15 to 25 mm; the particle with larger relative dielectric constant and smaller distance from the simulation conductor, has the greater electric field distortion degree.