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Aim: Estuarine vegetation routinely experiences natural tidal fluctuations and is highly vulnerable to extreme events such as heavy rainfall, leading to changes in plant population structure and adaptability. Genetic and epigenetic modifications are widely considered to be mechanisms of phenotypic variation, triggered in plants responding to extreme changing environments. However, understanding on correlations among genetic, epigenetic, and phenotypic variation of wild plant populations is still limited. Location: China. Methods: In this study, populations of the typical wetland clonal species Phragmites australis were selected from four estuaries along various latitudes in China. Genetic and epigenetic diversity and phenotypic variation of these populations were analysed. Results: Phenotypic variation of P. australis populations was the highest at Yellow River Estuary and the lowest at Min River Estuary. Across all estuaries, Genetic and epigenetic diversity was strongly linear‐correlated. Genetic diversity had significant correlations with variation in reproductive traits, whereas epigenetic diversity had significant correlations with variation in growth traits. Climatic factors of mean annual temperature and precipitation, as well as soil nitrogen and phosphorus, were negatively correlated with variation in genetic diversity, epigenetic diversity, and variation in reproductive traits of P. australis populations along latitudes. Variation in growth traits was negatively correlated with soil salinity, reflecting the limiting effect of salinity on plant growth. Main Conclusion: Our findings found that genetic and epigenetic variations may play different roles in phenotypic variation of P. australis populations along latitudes, the variation becomes greater when the climatic and edaphic conditions deteriorate. The findings shed new light on the adaptation and evolution of wetland plant populations along a large latitudinal scale, and may contribute to the revegetation of estuary wetlands. [ABSTRACT FROM AUTHOR]

This study aims to examine the electrochemical performance of aluminum-doped cathode materials, specifically Li [Li0.20Ni0.13Co0.13Mn0.54] O2 cathode materials. Various characterization techniques, including XRD, FE-SEM, TEM, FT-IR, and EIS, were employed to analyze the resulting materials. The XRD examination revealed consistent α-NaFeO2-type structures in both undoped and doped nanopowders with aluminum. The morphology of the nanopowders remained unaffected by doping, as observed in the FE-SEM images. TEM images indicated that all the powders, irrespective of doping, exhibited a hexagonal form. Notably, Aluminum doping was found to enhance electronic conductivity and structural stability, resulting in significantly improved cycle stability, albeit with a slight decrease in starting capacity. These findings highlight the importance of carefully controlling doping levels to optimize Li-ion battery performance. [ABSTRACT FROM AUTHOR]

Geosciences modelling and 3D geovisualization is growing and evolving rapidly. Driven by commercial urgency and an increase in data from sensor-based sources, there is an abundance of opportunities to analyze geosciences data in 3D and 4D. Geosciences modelling is developing in GIS based systems, 3D modelling through both game engines and custom programs, and the use of extended reality to further interact with data. The key limitations that are currently prevalent in 3D geovisualization in the geosciences are GIS representations having difficulty displaying 3D data and undergoing translations to pseudo-3D, thus losing fidelity, financial and personnel capital, processing issues with the terabytes worth of data and limited computing, digital occlusion and spatial interpretation challenges with users, and matching and alignment of 3D points. The future of 3D geovisualization lies in its accelerated growth, data management solutions, further interactivity in applications, and more information regarding the benefits and best practices in the field. [ABSTRACT FROM AUTHOR]

Both genetic and phenotypic intraspecific diversity play a crucial role in the ecological and evolutionary dynamics of organisms. Several studies have compared phenotypic divergence (Pst) and differentiation of neutral loci (Fst) to infer the relative roles of genetic drift and natural selection in population differentiation (Pst–Fst comparison). For the first time, we have assessed and compared the genetic variation and differentiation at the leaf trait level in two key macrophytes, Phragmites australis and Nuphar lutea.To this aim, we quantified and described the genetic structure and phenotypic diversity of both species in five lake systems in north‐central Italy. We then investigated the relative roles of genetic drift and natural selection on leaf trait differentiation (Pst–Fst), assuming that Fst reflects divergence caused only by genetic drift while Pst also incorporates the effects of selective dynamics on the phenotype.In terms of genetic structure, the results for P. australis were in line with those observed for other Italian and European conspecific populations. Conversely, N. lutea showed a more complex genetic structure than expected at the site level, probably due to the combined effect of genetic isolation and its mixed mating system. Both species exhibited high variability in leaf functional traits within and among sites, highlighting a high degree of phenotypic plasticity. Pst–Fst comparisons showed a general tendency towards directional selection in P. australis and a more complex pattern in N. lutea. Indeed, the drivers of phenotypic differentiation in N. lutea showed a variable mix of stabilising and directional selection or neutral divergence at most sites.The prevalence of vegetative over generative reproduction leads P. australis populations to be dominated by a few clones that are well adapted to local conditions, including phenotypes that respond plastically to the environment. In contrast, in N. lutea, the interaction of a mixed mating system and geographical isolation among distant sites tends to reduce the effect of outbreeding depression and provides the genetic basis for adaptive capacity.The first joint analysis of the genetic structure of these two key macrophytes allowed a better understanding of the relative roles of genetic drift and natural selection in the diversification of phenotypic traits within habitats dominated by P. australis and N. lutea. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Economics, Business, Politics, & International Relations (JEBPIR) / Ekonomi Işletme Siyaset ve Uluslararsi Ilişkiler Dergisi (JEBPIR) is the property of Ekonomi Isletme Siyaset ve Uluslararsi Iliskiler Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Bacillus turingiensis (Berliner) is a Gram positive, rod shaped and spore forming bacterium, which produces crystal proteins (proteinaceous inclusions), called δ-endotoxins, that have insecticidal action. The present investigation was carried out to isolate B. thuringiensis from soil, leaf, compost, leaf litter, diseased larvae and rhizosphere samples collected from the various locations in the states of Uttarakhand, Himachal Pradesh, Kerala, Karnataka and Maharashtra. A total of 300 samples were collected and isolation of the B. thuringiensis strains was carried out. The presence of crystalline inclusions in Bacilli like colonies was observed in 49 samples collected from the state of Uttarakhand, eight samples from Himachal Pradesh, six samples from Kerala, four samples from Karnataka and three samples from Maharashtra. Totally, 70 isolates showed milky white colonies with circular shape and colonies produced serrated margin similar to that of the reference strain HD1. Gram staining revealed that all the 70 isolates were rod-shaped, gram-positive bacteria, which were appeared to be blue or violet in colour under the Phase contrast microscope. Among the 70 isolates, 67 (97.74%) isolates showed bipyramidal type of crystal and the remaining three isolates such as, Bt-21, Bt-37 and Bt-278 showed square, elliptical and spherical crystal shape, respectively. The present study has established the diversity and richness of B. thuringiensis like isolates in soil and leaf samples collected from five selected states of India. [ABSTRACT FROM AUTHOR]

Invasive plants are ubiquitous features of many wetland systems, resulting in impacts that are extremely costly in both economic and ecological terms. Approximately twenty years ago, these impacts and many of the mechanisms underlying invasion were crystallized in a pair of now-classic review papers on the topic. These two contributions have guided substantial research efforts over the past two decades. Here, using a state-of-the-art review, we present an overview of research progress from the past 20 years and identify research priorities for the next 20 years. We structure these insights around key themes that emerge from those earlier reviews and emphasize ways wetland invasions might be distinguished from plant invasions in uplands. We first highlight research progress and priorities around the impacts of wetland plant invasions. We then do the same for seven broad mechanisms that have been postulated to enhance invasion success in wetlands. Invasive plants clearly impact wetlands across all levels of ecological organization and up to landscape scales, but generalizable conclusions are still lacking concerning what drives variation in impact magnitudes. One of the key mechanisms underlying invasion success reflects site-level variation in resource availability and, although we know that increased resources often lead to more opportunities for invasion, the role of discrete resource pulses and the way resource availability may interact with propagule pressure variability are poorly understood. Second, although release from natural enemies is a long-held potential driver of invasion success, recent insights support speculation that these effects may be especially pronounced in wetlands. Third, although most invasive wetland plants are considered good competitors, their simultaneous role as stress tolerators raises questions about whether expectations regarding life history tradeoffs may be less applicable for wetland invaders than for the upland species around which these theories were designed. Fourth, despite a keen understanding that wetland plant invaders are opportunistic, establishing quickly in response to disturbance, the central importance of seed and seedling traits has not been adequately studied to integrate life history theory across ontogenetic stages. Fifth, although many invasive wetland plants reproduce both sexually and asexually, the extent to which this mixed strategy contributes to their success as invaders has not been rigorously assessed. Sixth, despite observations that wetland invaders often exhibit a high degree of phenotypic variability, causal connections between the success of wetland invaders and either high population genetic diversity or high phenotypic plasticity have not been clearly established. Lastly, despite long-standing interests in whether interspecific hybridization contributes to wetland invader success, recent studies have highlighted evolutionary processes leading to variation in polyploidy and genome size as alternatives requiring additional study. We conclude with a vision for prioritizing wetland plant invasions research, presenting insights from this review aimed at inspiring future studies on remaining key uncertainties regarding the relative impacts of wetland vs. upland invaders and the relative importance of phenotypic plasticity, population genetic diversity, enemy release, and anthropogenic disturbances for influencing the success of invasive plants in wetland vs. upland systems. [ABSTRACT FROM AUTHOR]

Per- and polyfluoroalkyl substances (PFAS) pose a rapidly increasing global problem as their widespread use and high stability lead worldwide to water contamination, with significant detrimental health effects. [1] Supramolecular chemistry has been invoked to develop materials geared towards the specific capture of PFAS from water, [2] to reduce the concentration below advisory safety limits (e.g., 70 ng/L for the sum of perfluorooctane sulfonic acid, PFOS and perfluorooctanoic acid, PFOA). Scale-up and use in natural waters with high PFAS concentrations has hitherto posed a problem. Here we report a new type of host-guest interaction between deca-ammonium-functionalized pillar[5]arenes (DAF-P5s) and perfluoroalkyl acids. DAF-P5 complexes show an unprecedented 1 : 10 stoichiometry, as confirmed by isothermal calorimetry and X-ray crystallographic studies, and high binding constants (up to 10 6  M -1 ) to various polyfluoroalkyl acids. In addition, non-fluorinated acids do not hamper this process significantly. Immobilization of DAF-P5s allows a simple single-time filtration of PFAS-contaminated water to reduce the PFOS/PFOA concentration 10 6  times to 15-50 ng/L level. The effective and fast (<5 min) orthogonal binding to organic molecules without involvement of fluorinated supramolecular hosts, high breakthrough capacity (90 mg/g), and robust performance (>10 regeneration cycles without decrease in performance) set a new benchmark in PFAS-absorbing materials., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Interactions between invaders and resource availability may explain variation in their success or management efficacy. For widespread invaders, regional variation in plant response to nutrients can reflect phenotypic plasticity of the invader, genetic structure of invading populations, or a combination of the two. The wetland weed Alternanthera philoxeroides (alligatorweed) is established throughout the southeastern United States and California and has high genetic diversity despite primarily spreading clonally. Despite its history in the United States, the role of genetic variation for invasion and management success is only now being uncovered. To better understand how nutrients and genotype may influence A. philoxeroides invasion, we measured the response of plants from 26 A. philoxeroides populations (three cp haplotypes) to combinations of nitrogen (4 or 200 mg/L N) and phosphorus (0.4 or 40 mg/L P). We measured productivity (biomass accumulation and allocation), plant architecture (stem diameter and thickness, branching intensity), and foliar traits (toughness, dry matter content, percent N, and percent P). A short‐term developmental assay was also conducted by feeding a subset of plants from the nutrient experiment to the biological control agent Agasicles hygrophila, to determine whether increased availability of N or P to its host influenced agent performance, as has been previously suggested. Alternanthera philoxeroides haplotype Ap1 was more plastic than other haplotypes in response to nutrient amendments, producing more than double the biomass from low to high N and 50%–68% higher shoot: root ratio than other haplotypes in the high N treatment. Alternanthera philoxeroides haplotypes differed in seven of 10 variables in response to increased N. We found no differences in short‐term A. hygrophila development between haplotypes but mass was 23% greater in high than low N treatments. This study is the first to explore the interplay between nutrient availability, genetic variation, and phenotypic plasticity in invasive characteristics of the global invader, A. philoxeroides. [ABSTRACT FROM AUTHOR]

Komar, P.D. and Harris, E., 2022. Tectonic and climate-controlled hazards on the shores of Hawke's Bay, New Zealand. Journal of Coastal Research, 38(6), 1075–1095. Coconut Creek (Florida), ISSN 0749-0208. Elevations of the Hawke's Bay shore on the Pacific coast of New Zealand were altered by an earthquake in 1931, such that at its north end the gravel beach and shore-front properties were raised by 2 m, while elevations dropped by 1 m at its south end. Along the elevated shore, the morphology was altered from a low-lying gravel spit that had experienced frequent overwash events, changed to a gravel barrier ridge where its increased stability permitted construction of expensive homes. The central stretch of shore, where there was minimal change in elevations, continues to experience wave overtopping during storms and high tides, just as had occurred prior to the earthquake. The southern-most shore, where subsidence took place, experiences substantial property damage during winter storms. With projections of accelerated rates of rising sea levels and increased storm intensities produced by global warming, concerns are that the developed shore of the elevated gravel ridge will again suffer from erosion and overwash flooding. Analyses have been undertaken of the hourly measured tides, waves, and calculated swash run-up levels on the beaches, combined to yield a record of hourly total water levels at the shore. Its extremes have been compared with the elevations of the surveyed gravel ridges to yield assessments of the potential erosion and flooding hazards. Still greater hazard assessments have been based on a recognition that the morphologies of the surveyed ridges provide direct evidence for the most extreme water levels that occurred at times of major storms in the distant past, prior to the availability of the process data. Assessments of hazards expected 100 years into the future have included projections of both rising sea levels and evidence for increasing storm-wave heights. [ABSTRACT FROM AUTHOR]

Staphylococcus aureus is a pathobiont capable of colonizing and infecting most tissues within the human body, resulting in a multitude of different clinical outcomes. Adhesion of S. aureus to the host is crucial for both host colonization and the establishment of infections. Underlying the pathogen's success is a complex and diverse arsenal of adhesins. In this review, we discuss the different classes of adhesins, including a consideration of the various adhesion sites throughout the body and the clinical outcomes of each infection type. The development of therapeutics targeting the S. aureus host–pathogen interaction is a relatively understudied area. Due to the increasing global threat of antimicrobial resistance, it is crucial that innovative and alternative approaches are considered. Neutralizing virulence factors, through the development of antivirulence agents, could reduce bacterial pathogenicity and the ever‐increasing burden of S. aureus infections. This review provides insight into potentially efficacious adhesion‐associated targets for the development of novel decolonizing and antivirulence strategies. [ABSTRACT FROM AUTHOR]

The rapid invasion of the non‐native Phragmites australis (Poaceae, subfamily Arundinoideae) is a major threat to native wetland ecosystems in North America and elsewhere. We describe the first reference genome for P. australis and compare invasive (ssp. australis) and native (ssp. americanus) genotypes collected from replicated populations across the Laurentian Great Lakes to deduce genomic bases driving its invasive success. Here, we report novel genomic features including a Phragmites lineage‐specific whole genome duplication, followed by gene loss and preferential retention of genes associated with transcription factors and regulatory functions in the remaining duplicates. Comparative transcriptomic analyses revealed that genes associated with biotic stress and defence responses were expressed at a higher basal level in invasive genotypes, but native genotypes showed a stronger induction of defence responses when challenged by a fungal endophyte. The reference genome and transcriptomes, combined with previous ecological and environmental data, add to our understanding of mechanisms leading to invasiveness and support the development of novel, genomics‐assisted management approaches for invasive Phragmites. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In addition to being one of the primary building block materials of living cells, glycans are also favorable candidates for therapeutic applications. In the mid‐20th century, the progress of glycans in the drug discovery field became surpassed by protein and DNA‐focused treatments. However, the emergence of new analytical tools and methods to synthesize structurally specific glycans has encouraged and motivated the scientific community toward the development of glycan‐based therapeutics. This review discusses the reemergence of glycan‐based agents in the last decade and the technical strategies that played a key role in bringing the glycan‐based treatments into the limelight of modern medicine. The review also includes the application of native glycans as the therapeutic agents along with the chemically engineered cell surface glycans and proteins to meet the preclinical and clinical scenario. Glycan‐based therapeutic materials hold a huge potential that can be harnessed to meet the clinical needs in medicine. [ABSTRACT FROM AUTHOR]

Phenotypic plasticity is commonly considered to contribute to the invasion success of invasive species. However, the importance of phenotypic plasticity, nitrogen (N) levels and warming to the invasion of invasive species is unclear. The effects of warming and N addition on the morphology, biomass allocation and biochemistry traits of Solidago canadensis and their plasticity were investigated by conducting a pot experiment. The results showed that the effect of N addition on biomass was improved for S. canadensis; whereas warming displayed no significant effect, their positive synergistic interact effect resulted in the overall significant increase in plant performance. The mean phenotypic plasticity indices (MPPI) of biochemistry and total parameters demonstrated a difference between operations, and the higher value was observed in N interaction with temperature treatments than N addition or warming alone. The observed MPPI indicated the biochemistry parameters > morphological parameters > allocation parameters. The MPPI of biochemistry parameters, morphological parameters and total parameters exhibited significant and positive correlations with N level and MPPI of morphological parameters was also significantly positively correlated with the fitness of S. canadensis. These results indicated that the global warming and N addition would make the invaded habitat more suitable for the growth of invasive S. canadensis, and even may effectively increase the invasion risk of S. canadensis through the enhanced phenotypic plasticity, which is a crucial factor to help species deal with the changing environment. [ABSTRACT FROM AUTHOR]

This work focuses on the ways in which educational activism has the ability to disrupt the political economy. This article also utilizes the epistemology and ontology of educational activists to determine the methods that activism develops, approaches and implements. The co-construction of pedagogy and spaces that are cultivated that explore the actionable pursuits of liberation that impacts human geography are explained by participants. Through narrative inquiry and narrative analysis, the path to unlearning and co-creating efficacious environmental shifts was explored among five participants. These participants shared analysis that contemplates ways that educational activism can disrupt the political economy, produce cultural epistemological and ontological homonyms, and shake the ground of oppressive space (spatial and mental) in hopes of deconstructing and building the foundation of new liberatory realities. [ABSTRACT FROM AUTHOR]

Aim: Introduced species may display or foster novel latitudinal clines because they are not well adapted to their new habitats. We tested the hypothesis that the latitudinal cline in nematode diversity in salt marshes would differ between the native (United States) and introduced (China) ranges of Spartina alterniflora. Location: East Coasts of the United States (30.32–43.33°N) and China (30.36–39.14°N). Methods: We extracted nematodes from soil samples collected at 32 sites along the United States East Coast and 41 sites along the Chinese coast. We compared latitudinal patterns in nematode diversity and composition between the native and introduced ranges. Results: In the native range of S. alterniflora, nematode richness at lower latitudes was almost twice as high as that at higher latitudes. In contrast, we found no latitudinal pattern in nematode richness or diversity in the introduced range of S. alterniflora. Nematode genus richness at all sites in China was about half that at lower latitudes in the United States. Beta diversity of nematodes increased with geographic distance in the United States, but not China. Main conclusions: Nematode diversity did not show latitudinal clines in salt marshes dominated by introduced S. alterniflora in China. A likely explanation is that the recently introduced populations are still relatively genetically homogenous, whereas in the native range, genetic variation in plant populations across latitude drives different nematode communities. We suggest that future studies of introduced species will gain additional insights by taking an explicitly geographic perspective. [ABSTRACT FROM AUTHOR]

Phragmites australis is a widespread invasive plant species in the USA that greatly impacts estuarine wetlands by creating dense patches and outcompeting other plants. The invasion of Phragmites into wetland ecosystems is known to decrease biodiversity, destroy the habitat of threatened and endangered bird species, and alter biogeochemistry. While the impact of Phragmites is known, the spatial extent of this species is challenging to document due to its fragmented occurrence. Using high-resolution imagery from the National Agriculture Imagery Program (NAIP) from 2017, we evaluated a geospatial method of mapping the spatial extent of Phragmites across the state of DE. Normalized difference vegetation index (NDVI) and principal component analysis (PCA) bands are generated from the NAIP data and used as inputs in a random forest classifier to achieve a high overall accuracy for the Phragmites classification of around 95%. The classified gridded dataset has a spatial resolution of 1 m and documents the spatial distribution of Phragmites throughout the state's estuarine wetlands (around 11%). Such detailed classification could aid in monitoring the spread of this invasive species over space and time and would inform the decision-making process for landscape managers., (© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Field experiment was carried at Burji, Bonke and Chencha during the 2018 cropping season to evaluate the effects of host resistance and fungicide application on yellow and stem rusts and grain yield (GY) of bread wheat. Five wheat varieties and four different fungicides were included as treatment and laid out in factorial arrangement in randomized complete block design with three replications. Significant (p ≤ 0.01) difference was observed in the magnitude of the parameters of disease and crop measured between treatments. Results showed that the mean terminal severities of yellow and stem rusts were highest at Chencha than at Burji and Bonke. Yellow and stem rust terminal severities as low as 46.41%, 40.69%, 29.22%, 28.24% and 21.74% and 43.67%, 42.54%, 40.93%, 16.07% and 17.15% were recorded on Hidase, Kubsa, Ogolcho, Wane and Shorima varieties, respectively, due to the integrated use of Tilt 250 EC, Rex® Dou and Natura 250 EW foliar applications across the three locations. Crosswise assessment revealed that the lowest area under the disease progress curve (AUDPC) of yellow rust of 15.73%, 14.93%, 10.42%, 8.79% and 7.67%-days was recorded on Hidase, Kubsa, Ogolcho, Wane and Shorima varieties, respectively, and that of stem rust of 18.96%, 17.33%, 16.36%, 6.80% and 6.37%-days was registered on Kubsa, Ogolcho, Hidase, Shorima and Wane varieties, respectively, as a result of combined use of Tilt 250 EC, Rex® Dou and Natura 250 EW foliar applications. The combined effect of variety and fungicide application in addition to environmental variability exhibited pronounced effects on the epidemic development of yellow and stem rusts through their effects on disease progress rate and spike infection. Rex® Dou and Natura 250 EW fungicides in combination with all the evaluated varieties proved to be effective against the rust management and gave the higher values of yield parameters and monitory advantage over the unsprayed plots. GY loss of up to 69.64% was recorded on unsprayed plots of Ogolcho as compared to fungicide sprayed plots of other varieties evaluated. Thus, Rex® Dou and Natura 250 EW fungicides in combination with wheat variety having a different level of resistance to wheat rusts could be suggested to the farmers in the study areas and elsewhere with similar agro-ecological conditions for efficient management and optimization of the GY. Further studies have to be sought in similar and other agro-ecologies elsewhere in Ethiopia for at least two consecutive years over locations to come up with a solid recommendation. [ABSTRACT FROM AUTHOR]

The outcomes of invasive plant removal efforts are influenced by management decisions, but are also contingent on the uncontrolled spatial and temporal context of management areas. Phragmites australis is an aggressive invader that is intensively managed in wetlands across North America. Treatment options have been understudied, and the ecological contingencies of management outcomes are poorly understood. We implemented a 5‐year, multi‐site experiment to evaluate six Phragmites management treatments that varied timing (summer or fall) and types of herbicide (glyphosate or imazapyr) along with mowing, plus a nonherbicide solarization treatment. We evaluated treatments for their influence on Phragmites and native plant cover and Phragmites inflorescence production. We assessed plant community trajectories and outcomes in the context of environmental factors. The summer mow, fall glyphosate spray treatment resulted in low Phragmites cover, high inflorescence reduction, and provided the best conditions for native plant recruitment. However, returning plant communities did not resemble reference sites, which were dominated by ecologically important perennial graminoids. Native plant recovery following initial Phragmites treatments was likely limited by the dense litter that resulted from mowing. After 5 years, Phragmites mortality and native plant recovery were highly variable across sites as driven by hydrology. Plots with higher soil moisture had greater reduction in Phragmites cover and more robust recruitment of natives compared with low moisture plots. This moisture effect may limit management options in semiarid regions vulnerable to water scarcity. We demonstrate the importance of replicating invasive species management experiments across sites so the contingencies of successes and failures can be better understood. [ABSTRACT FROM AUTHOR]

Nearshore slope, defined as the cross-shore gradient of the subaqueous profile, is an important input parameter which affects hydrodynamic and morphological coastal processes. It is used in both local and large-scale coastal investigations. However, due to unavailability of data, most studies, especially those that focus on continental or global scales, have historically adopted a uniform nearshore slope. This simplifying assumption could however have far-reaching implications for predictions/projections thus obtained. Here, we present the first global dataset of nearshore slopes with a resolution of 1 km at almost 620 000 points along the global coastline. To this end, coastal profiles were constructed using global topo-bathymetric datasets. The results show that the nearshore slopes vary substantially around the world. An assessment of coastline recession driven by sea level rise (SLR) (for an arbitrary 0.5 m SLR) with a globally uniform coastal slope of 1 : 100, as carried out in previous studies, and with the spatially variable coastal slopes computed herein shows that, on average, the former approach would underestimate coastline recession by about 40 %, albeit with significant spatial variation. The final dataset has been made publicly available at 10.4121/uuid:a8297dcd-c34e-4e6d-bf66-9fb8913d983d (Athanasiou, 2019). [ABSTRACT FROM AUTHOR]

Stimuli-responsive receptors for the recognition unit of the cholera toxin (CTB) have been prepared by attaching multiple copies of its natural carbohydrate ligand, the GM1 oligosaccharide, to a thermoresponsive polymer scaffold. Below their lower critical solution temperature (LCST), polymers complex CTB with nanomolar affinity. When heated above their LCST, polymers undergo a reversible coil to globule transition which renders a proportion of the carbohydrate recognition motifs inaccessible to CTB. This thermally-modulated decrease in the avidity of the material for the protein has been used to reversibly capture CTB from solution, enabling its convenient isolation from a complex mixture. [ABSTRACT FROM AUTHOR]

Let him that itches block NPR1: Chronic itch is an uncomfortable sensation with major impact on the quality of life. The pathophysiology of itch is not clearly elucidated, and the few available treatments are mostly ineffective. The natriuretic peptide receptor 1 (NPR1) has been recently shown to promote itch in mice; however, a peptide NPR1 inhibitor showed poor effects in mice. Investigating the reason for these negative results, Solinski et al. now show that the reported NPR1 inhibitor acted as partial agonist of the receptor, thus explaining the failure in relieving itch. Using high-throughput screening, the authors identified small-molecule human NPR1 antagonists. The molecules were able to relieve chronic itch in mice without inducing adverse effects. There is a major clinical need for new therapies for the treatment of chronic itch. Many of the molecular components involved in itch neurotransmission are known, including the neuropeptide NPPB, a transmitter required for normal itch responses to multiple pruritogens in mice. Here, we investigated the potential for a novel strategy for the treatment of itch that involves the inhibition of the NPPB receptor NPR1 (natriuretic peptide receptor 1). Because there are no available effective human NPR1 (hNPR1) antagonists, we performed a high-throughput cell-based screen and identified 15 small-molecule hNPR1 inhibitors. Using in vitro assays, we demonstrated that these compounds specifically inhibit hNPR1 and murine NPR1 (mNPR1). In vivo, NPR1 antagonism attenuated behavioral responses to both acute itch– and chronic itch–challenged mice. Together, our results suggest that inhibiting NPR1 might be an effective strategy for treating acute and chronic itch. [ABSTRACT FROM AUTHOR]

The natural recolonization of native plant communities following invasive species management is notoriously challenging to predict, since outcomes can be contingent on a variety of factors including management decisions, abiotic factors, and landscape setting. The spatial scale at which the treatment is applied can also impact management outcomes, potentially influencing plant assembly processes and treatment success. Understanding the relative importance of each of these factors for plant community assembly can help managers prioritize patches where specific treatments are likely to be most successful. Here, using effects size analyses, we evaluate plant community responses following four invasive Phragmites australis management treatments (1: fall glyphosate herbicide spray, 2: summer glyphosate herbicide spray, 3: summer imazapyr herbicide spray, 4: untreated control) applied at two patch scales (12,000 m2 and 1,000 m2) and monitored for 5 years. Using variation partitioning, we then evaluated the independent and shared influence of patch scale, treatment type, abiotic factors, and landscape factors on plant community outcomes following herbicide treatments. We found that Phragmites reinvaded more quickly in large patches, particularly following summer herbicide treatments, while native plant cover and richness increased at a greater magnitude in small patches than large. Patch scale, in combination with abiotic and landscape factors, was the most important driver for most plant responses. Compared with the small plots, large patches commonly had deeper and more prolonged flooding, and were in areas with greater hydrologic disturbance in the landscape, factors associated with reduced native plant recruitment and greater Phragmites cover. Small patches were associated with less flooding and landscape disturbance, and more native plants in the surrounding landscape than large patches, factors which promoted higher native plant conservation values and greater native plant cover and richness. Herbicide type and timing accounted for very little of the variation in native plant recovery, emphasizing the greater importance of patch selection for better management outcomes. To maximize the success of treatment programs, practitioners should first manage Phragmites patches adjacent to native plant species and in areas with minimal hydrologic disturbance. [ABSTRACT FROM AUTHOR]

ABSTRACT Lipiec, E.; Ruggiero, P.; Mills, A.; Serafin, K.A.; Bolte, J.; Corcoran, P.; Stevenson, J.; Zanocco, C., and Lach, D., 2018. Mapping out climate change: Assessing how coastal communities adapt using alternative future scenarios. Coastal communities are increasingly experiencing climate change–induced coastal disasters and chronic flooding and erosion. Decision makers and the public alike are struggling to reconcile the lack of “fit” between a rapidly changing environment and relatively rigid governance structures. In efforts to bridge this environment-governance gap in Tillamook County, Oregon, stakeholders formed a knowledge-to-action network (KTAN). The KTAN examined alternative future coastal policy and climate scenarios through extensive stakeholder engagement and the spatially explicit agent-based modeling framework Envision. The KTAN's results were further evaluated through a two-step mixed methods approach. First, KTAN-identified metrics were quantitatively assessed and compared under present-day vs. alternative policy scenarios. Second, the feasibility of implementing these policy scenarios was qualitatively evaluated through a review of governmental regulations and semistructured interviews. The findings show that alternative policy scenarios ranged from significantly beneficial to extremely harmful to coastal buildings and beach accessibility in comparison to present-day policies, and they were relatively feasible to almost impossible to implement. Beneficial policies that lower impacts of flooding and erosion clearly diverge from the existing regulatory environment, which inhibits their implementation. In response, leadership and cross-sector cooperation and coordination can help to overcome mixed interests and motivations, and increase information exchange between and within the public and government organizations. The combination of stakeholder engagement, an alternative futures modeling framework, and the robust quantitative and qualitative evaluation of policy scenarios provides a powerful model for coastal communities hoping to adapt to climate change along any coastline. [ABSTRACT FROM AUTHOR]

Abstract: Atopic dermatitis (AD) is a chronically relapsing, pruritic inflammation of the skin with dryness and disturbed skin barrier function. Recently, we established that IL‐31 treatment of human 3D skin models resulted in a disrupted skin barrier phenotype resembling AD. In this model, we found that IL‐31 interferes with the differentiation of keratinocytes and inhibits the expression of terminal differentiation markers. In the present study, we investigated the effects of a ceramide‐containing water‐in‐oil skin care ointment on the physical skin barrier structure and function in disrupted skin barrier models, generated either by using primary normal human epidermal keratinocytes (NHEK) or HaCaT cells. We observed that the physical skin barrier of the models recovered after daily topical treatment with the ceramide‐containing ointment. Topical application of the ointment prevented downregulation of filaggrin and disorganization of other differentiation markers, such as keratin 10 and β4‐integrin, as demonstrated by immunohistological analysis. The expression of Ki67 was also upregulated in response to the ointment. Furthermore, functional studies revealed that local application of the ointment diminished the increased uptake of fluorescently labelled recombinant allergens of timothy grass (phl p1) in our model. In conclusion, our data revealed that topical application of a ceramide‐containing skin care ointment reduced IL‐31 induced impairments of the physical skin barrier and skin barrier function in an in vitro model of the disrupted skin barrier. This standardized model can be utilized in the future to monitor ex vivo effects of various topical therapies on skin morphology, physiology, and gene expression. [ABSTRACT FROM AUTHOR]

Abstract: Elevated atmospheric carbon dioxide (eCO2) concentrations and nitrogen (N) enrichment are known to enhance plant productivity and invasion. However, the implications of their interactive effects for plant productivity are not well understood, especially at the stand scale, presumably because morphological and physiological responses to these global change factors are rarely studied together in the field or assessed at the stand level. We first determined how leaf‐level morphological and physiological traits responded to factorial combinations of ambient and elevated CO2 and N. We collected trait data from the model invasive species Phragmites australis (common reed) that were measured over 3 years in a long‐term global change field experiment. We then combined the trait data and additional descriptions of P. australis canopies in a simulation model of carbon assimilation to determine how morphology and physiology contribute to P. australis’ stand‐scale productivity. At the leaf level, we found that light‐saturated rates of photosynthesis were strongly stimulated by eCO2 (37%) and that this effect was enhanced by increasing salinity. N had a smaller effect (17% stimulation) on physiological responses than eCO2, but leaf morphological traits responded primarily to N; plant height increased by 27% and leaf area increased by 47%. Stand‐scale simulations demonstrated that that morphological and physiological adjustments induced approximately additive responses when P. australis experienced both eCO2 and N enrichment. The simulations also indicated that morphological changes (which were primarily associated with canopy size) influenced stand‐scale carbon assimilation more than physiological changes. Moreover, 97% of the N response was due to changes in morphology, whereas 62% of the eCO2 response was caused by physiological shifts. Our analysis indicates that morphological and physiological trait responses to elevated CO2 and nitrogen are likely to enhance the productivity of P. australis in complementary ways, potentially accelerating its invasion in North America. Furthermore, our data suggest that changes in morphological traits may have a greater influence on carbon gain than leaf‐level physiology under near‐future environmental conditions. Our study also highlights the importance of accounting for both morphological and physiological responses when attempting to infer global change responses from leaf‐level data. A plain language summary is available for this article. [ABSTRACT FROM AUTHOR]

Abstract: While many introduced invasive species can increase genetic diversity through multiple introductions and/or hybridization to colonize successfully in new environments, others with low genetic diversity have to persist by alternative mechanisms such as epigenetic variation. Given that Phragmites australis is a cosmopolitan reed growing in a wide range of habitats and its invasion history, especially in North America, has been relatively well studied, it provides an ideal system for studying the role and relationship of genetic and epigenetic variation in biological invasions. We used amplified fragment length polymorphism (AFLP) and methylation‐sensitive (MS) AFLP methods to evaluate genetic and epigenetic diversity and structure in groups of the common reed across its range in the world. Evidence from analysis of molecular variance (AMOVA) based on AFLP and MS‐AFLP data supported the previous conclusion that the invasive introduced populations of P. australis in North America were from European and Mediterranean regions. In the Gulf Coast region, the introduced group harbored a high level of genetic variation relative to originating group from its native location, and it showed epigenetic diversity equal to that of the native group, if not higher, while the introduced group held lower genetic diversity than the native. In the Great Lakes region, the native group displayed very low genetic and epigenetic variation, and the introduced one showed slightly lower genetic and epigenetic diversity than the original one. Unexpectedly, AMOVA and principal component analysis did not demonstrate any epigenetic convergence between native and introduced groups before genetic convergence. Our results suggested that intertwined changes in genetic and epigenetic variation were involved in the invasion success in North America. Although our study did not provide strong evidence proving the importance of epigenetic variation prior to genetic, it implied the similar role of stable epigenetic diversity to genetic diversity in the adaptation of P. australis to local environment. [ABSTRACT FROM AUTHOR]

Abstract: In this study, we investigated anti‐dermatitic effects of astaxanthin (AST) in phthalic anhydride (PA)‐induced atopic dermatitis (AD) animal model as well as in vitro model. AD‐like lesion was induced by the topical application of 5% PA to the dorsal skin or ear of Hos:HR‐1 mouse. After AD induction, 100 μL of 1 mg/mL and 2 mg/mL of AST (10 μg or 20 μg/cm2) was spread on the dorsum of ear or back skin three times a week for four weeks. We evaluated dermatitis severity, histopathological changes and changes in protein expression by Western blotting for inducible nitric oxide synthase (iNOS), cyclooxygenase‐2 (COX‐2) and nuclear factor‐κB (NF‐κB) activity. We also measured tumor necrosis factor‐α (TNF‐α), interleukin‐1β (IL‐1β), interleukin‐6 (IL‐6) and immunoglobulin E (IgE) concentration in the blood of AD mice by enzyme‐linked immunosorbent assay (ELISA). AST treatment attenuated the development of PA‐induced AD. Histological analysis showed that AST inhibited hyperkeratosis, mast cells and infiltration of inflammatory cells. AST treatment inhibited expression of iNOS and COX‐2, and NF‐κB activity as well as release of TNF‐α, IL‐1β, IL‐6 and IgE. In addition, AST (5, 10 and 20 μM) potently inhibited lipopolysaccharide (LPS) (1 μg/mL)‐induced nitric oxide (NO) production, expression of iNOS and COX‐2 and NF‐κB DNA binding activities in RAW 264.7 macrophage cells. Our data demonstrated that AST could be a promising agent for AD by inhibition of NF‐κB signalling. [ABSTRACT FROM AUTHOR]

Phragmites australis is a subcosmopolitan species typical of wetlands being studied in Europe for its disappearance from natural stands, a phenomenon called reed die-back syndrome (RDBS). Although it is conjectured that low genetic variability contributes to RDBS, this aspect remains neglected to this day. Using a molecular fingerprinting approach and a sequence analysis of the trnT-trnL/rbcL-psaI regions of cpDNA, this study aimed to compare the genetic structure of stable vs. RDBS-affected P. australis stands from five wetlands of central Italy. Beforehand, in order to characterize the health condition of reed populations, the occurrence of the main macromorphological descriptors for RDBS was considered on 40 reed stands. Soil samples were also collected to examine the total content of heavy metals. The current study analyzed cpDNA in 19 samples and AFLP profiles in 381 samples to investigate the genetic structure of Phragmites populations. Based on the multinomial-Dirichlet model, an analysis of candidate loci under selective pressure was also performed. The relationships among AFLP data, RDBS descriptors and chemicals were evaluated with the use of Linear Mixed Models. The analysis of the cpDNA shows the occurrence of the haplotypes M (the most widespread), and K here recorded for the first time in Italy. Three new haplotypes were also described. The DNA fingerprinting analysis has produced a total of 322 loci (98% polymorphic) and shows the medium-to-high amount of genetic diversity. The significant genetic differentiation among wetlands (Fst = 0.337) suggests either low gene flow or small effective population size. Moreover, the low amount of outlier loci (only 5; l.5% of the total), seems to indicate the scarce occurrence of selective pressure upon the reed's genome. Genetic diversity increased in relationship to the decrease in diameter and of flowering buds of the reed, two of the trends associated with the die-back. The current study rejects the hypothesis that genetic diversity massively contributed to RDBS. Moreover, significant relationships between genetic diversity and the total concentration of some heavy metals (Cr, Cu, and Zn) were highlighted, indicating possible genotoxic effects on P. australis. The current study represents a fact-finding background useful for the conservation of common reed. [ABSTRACT FROM AUTHOR]

Identifying the factors that influence spatial genetic structure among populations can provide insights into the evolution of invasive plants. In this study, we used the common reed (Phragmites australis), a grass native in Europe and invading North America, to examine the relative importance of geographic, environmental (represented by climate here), and human effects on population genetic structure and its changes during invasion. We collected samples of P. australis from both the invaded North American and native European ranges and used molecular markers to investigate the population genetic structure within and between ranges. We used path analysis to identify the contributions of each of the three factors—geographic, environmental, and humanrelated—to the formation of spatial genetic patterns. Genetic differentiation was observed between the introduced and native populations, and their genetic structure in the native and introduced ranges was different. There were strong effects of geography and environment on the genetic structure of populations in the native range, but the human-related factors manifested through colonization of anthropogenic habitats in the introduced range counteracted the effects of environment. The between-range genetic differences among populations were mainly explained by the heterogeneous environment between the ranges, with the coefficient 2.6 times higher for the environment than that explained by the geographic distance. Human activities were the primary contributor to the genetic structure of the introduced populations. The significant environmental divergence between ranges and the strong contribution of human activities to the genetic structure in the introduced range suggest that invasive populations of P. australis have evolved to adapt to a different climate and to human-made habitats in North America. [ABSTRACT FROM AUTHOR]

Phragmites australis is a cosmopolitan grass and often the dominant species in the ecosystems it inhabits. Due to high intraspecific diversity and phenotypic plasticity, P. australis has an extensive ecological amplitude and a great capacity to acclimate to adverse environmental conditions; it can therefore offer valuable insights into plant responses to global change. Here we review the ecology and ecophysiology of prominent P. australis lineages and their responses to multiple forms of global change. Key findings of our review are that: (1) P. australis lineages are well-adapted to regions of their phylogeographic origin and therefore respond differently to changes in climatic conditions such as temperature or atmospheric CO2; (2) each lineage consists of populations that may occur in geographically different habitats and contain multiple genotypes; (3) the phenotypic plasticity of functional and fitness-related traits of a genotype determine the responses to global change factors; (4) genotypes with high plasticity to environmental drivers may acclimate or even vastly expand their ranges, genotypes of medium plasticity must acclimate or experience range-shifts, and those with low plasticity may face local extinction; (5) responses to ancillary types of global change, like shifting levels of soil salinity, flooding, and drought, are not consistent within lineages and depend on adaptation of individual genotypes. These patterns suggest that the diverse lineages of P. australis will undergo intense selective pressure in the face of global change such that the distributions and interactions of co-occurring lineages, as well as those of genotypes within-lineages, are very likely to be altered. We propose that the strong latitudinal clines within and between P. australis lineages can be a useful tool for predicting plant responses to climate change in general and present a conceptual framework for using P. australis lineages to predict plant responses to global change and its consequences. [ABSTRACT FROM AUTHOR]

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Interactions between introduced plants and soils they colonize are central to invasive species success in many systems. Belowground biotic and abiotic changes can influence the success of introduced species as well as their native competitors. All plants alter soil properties after colonization but, in the case of many invasive plant species, it is unclear whether the strength and direction of these soil conditioning effects are due to plant traits, plant origin, or local population characteristics and site conditions in the invaded range. Phragmites australis in North America exists as a mix of populations of different evolutionary origin. Populations of endemic native Phragmites australis americanus are declining, while introduced European populations are important wetland invaders. We assessed soil conditioning effects of native and non-native P. australis populations on early and late seedling survival of native and introduced wetland plants. We further used a soil biocide treatment to assess the role of soil fungi on seedling survival. Survival of seedlings in soils colonized by P. australis was either unaffected or negatively affected; no species showed improved survival in P. australis-conditioned soils. Population of P. australis was a significant factor explaining the response of seedlings, but origin (native or non-native) was not a significant factor. Synthesis: Our results highlight the importance of phylogenetic control when assessing impacts of invasive species to avoid conflating general plant traits with mechanisms of invasive success. Both native (noninvasive) and non-native (invasive) P. australis populations reduced seedling survival of competing plant species. Because soil legacy effects of native and non-native P. australis are similar, this study suggests that the close phylogenetic relationship between the two populations, and not the invasive status of introduced P. australis, is more relevant to their soil-mediated impact on other plant species. [ABSTRACT FROM AUTHOR]

This account presents comprehensive information on the biology of Phragmites australis (Cav.) Trin. ex Steud. ( P. communis Trin.; common reed) that is relevant to understanding its ecological characteristics and behaviour. The main topics are presented within the standard framework of the Biological Flora of the British Isles: distribution, habitat, communities, responses to biotic factors and to the abiotic environment, plant structure and physiology, phenology, floral and seed characters, herbivores and diseases, as well as history including invasive spread in other regions, and conservation., Phragmites australis is a cosmopolitan species native to the British flora and widespread in lowland habitats throughout, from the Shetland archipelago to southern England. It is widespread throughout Ireland and is native in the Channel Islands. Native populations occur naturally in temperate zones and on every continent except Antarctica. Some populations in Australia and North America have been introduced from elsewhere and have become naturalized, and in North America, some of these are known to be invasive where they compete with native local populations of P. australis. Typical habitats in Britain range from shallow still water along waterbody edges to marshlands, saltmarshes and drier habitat on slopes up to 470 m above sea level. Additional habitats outside Britain are springs in arid areas, riverine lowlands (−5 m above sea level) and groundwater seepage points up to 3600 m above sea level. Although it occurs on a wide range of substrates and can tolerate pH from 2·5 to 9·8, in Britain it prefers pH >4·5 and elsewhere it thrives in mildly acidic to mildly basic conditions ( pH 5·5-7·5). The species plays a pivotal role in the successional transition from open water to woodland., Phragmites australis is a tall, helophytic, wind-pollinated grass with annual shoots up to 5 m above-ground level from an extensive system of rhizomes and stolons. A single silky inflorescence develops at the end of each fertile stem and produces 500-2000 seeds. The plant is highly variable genetically and morphologically., Expansion of established populations is mainly through clonal growth of the horizontal rhizome system and ground-surface stolons, while new populations can establish from rhizomes, stem fragments and seeds. Shoots generally emerge in spring, with timing determined primarily by physiology that is mediated by external conditions (e.g. local climate including frost)., Many populations in the British Isles have experienced some decline over the past two decades and there is concern that there might be further losses along the east coast as sea level rises. There have recently also been localized expansions, especially in highly modified habitats, where P. australis reedbeds have been planted as wildlife habitat, rehabilitated mineral and gravel beds, and bioremediation filter beds for industrial and transport infrastructure. Native populations outside Britain also demonstrate both types of trend: they are declining in many parts of Western Europe and North America, yet also colonize many disturbed, ruderal habitats (e.g. the edges of agricultural fields and motorways) throughout its native and non-native range and can form 'weedy' monodominant populations (e.g. in Australia and China). [ABSTRACT FROM AUTHOR]

Multivalent carbohydrate-protein interactions are frequently involved in essential biological recognition processes. Accordingly, multivalency is often also exploited for the design of high-affinity lectin ligands aimed at the inhibition of such processes. In a previous study (D. Schwefel et al., J. Am. Chem. Soc. 2010, 132, 8704-8719) we identified a tetravalent cyclopeptide-based ligand with nanomolar affinity to the model lectin wheat germ agglutinin (WGA). To unravel the structural features of this ligand required for high-affinity binding to WGA, we synthesized a series of cyclic and linear neoglycopeptides that differ in their conformational freedom as well as the number of GlcNAc residues. Combined evidence from isothermal titration calorimetry (ITC), enzyme-linked lectin assays (ELLA), and dynamic light scattering (DLS) revealed different binding modes of tetra- and divalent ligands and that conformational preorganization of the ligands by cyclization is not a prerequisite for achieving high binding affinities. The high affinities of the tetravalent ligands rather stem from their ability to form crosslinks between several WGA molecules. The results illustrate that binding affinities and mechanisms are strongly dependent on the used multivalent system which offers opportunities to tune and control binding processes. [ABSTRACT FROM AUTHOR]

Knowing the relative contribution of vegetative propagation and sexual reproduction to the dispersal and establishment of exotic plants is crucial for devising efficient control strategies. This is particularly true for the common reed ( Phragmites australis), one of the most invasive species in North America., For the first time, we combined in situ field observations and genetic evidence, based on two genotyping techniques, that is microsatellite markers ( SSR) and genotyping by sequencing ( GBS), to determine the propagation strategies of this invader at its northern distribution limit in North America and especially in roadside ditches., Field observations revealed that, in a region where the common reed is already abundant, both seeds and plant fragments contributed to the establishment of new populations. Newly established individuals originated mostly (84%) from seeds rather than fragments, but a larger proportion of individuals originating from fragments survived the second year compared to seedlings., High genetic diversity among marsh and roadside common reed stands indicated the prime role of sexual reproduction for dispersal. The vast majority of genotypes were found in only one stand; such high genetic variability can only be explained by sexual reproduction. Half the surveyed stands comprised a single clone, suggesting that local expansion mainly occurred vegetatively. As the small proportion of SSR genotypes initially thought to be common between distant stands proved to be distinct (as revealed by GBS data), it is likely that all the stands examined were initially founded by genetically distinct individuals., Synthesis. Our study suggests that long-distance dispersal by seeds is important for the common reed, in marshes and roadsides, while both seeds and plant fragments contribute to short-distance dispersal along roads, at least in regions where the species is already abundant. The success of this invader in North America seems to be attributable to a reproduction strategy combining the advantages of sexuality with those of vegetative propagation. Moreover, this study shows that the GBS approach strongly reduces uncertainties associated with the use of a limited number of markers. This approach is especially valuable for ecologists dealing with an ever-increasing number of invaders, of which few have identified microsatellite markers. [ABSTRACT FROM AUTHOR]

The five B-subunits (CTB5) of the Vibrio cholerae (cholera) toxin can bind to the intestinal cell surface so the entire AB5 toxin can enter the cell. Simultaneous binding can occur on more than one of the monosialotetrahexosylganglioside (GM1) units present on the cell surface. Such simultaneous binding arising from the toxins multivalency is believed to enhance its affinity. Thus, blocking the initial attachment of the toxin to the cell surface using inhibitors with GM1 subunits has the potential to stop the disease. Previously we showed that tetravalent GM1 molecules were sub-nanomolar inhibitors of CTB5. In this study, we synthesized a pentavalent version and compared the binding and potency of penta- and tetravalent cholera toxin inhibitors, based on the same scaffold, for the first time. The pentavalent geometry did not yield major benefits over the tetravalent species, but it was still a strong inhibitor, and no major steric clashes occurred when binding the toxin. Thus, systems which can adopt more geometries, such as those described here, can be equally potent, and this may possibly be due to their ability to form higher-order structures or simply due to more statistical options for binding. [ABSTRACT FROM AUTHOR]