Articles de revues : « Invasion time »

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Stigall, Alycia L. « The Invasion Hierarchy : Ecological and Evolutionary Consequences of Invasions in the Fossil Record ». Annual Review of Ecology, Evolution, and Systematics 50, n^o 1 (2 novembre 2019) : 355–80. http://dx.doi.org/10.1146/annurev-ecolsys-110617-062638.

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Species invasions are pervasive in Earth history, yet the ecological and evolutionary consequences vary greatly. Ancient invasion events can be organized in a hierarchy of increasing invasion intensity from ephemeral invasions to globally pervasive invasive regimes. Each level exhibits emergent properties exceeding the sum of interactions at lower levels. Hierarchy levels correspond to, but do not always exactly correlate with, geographic extent of invasion success. The ecological impacts of lower-level impacts can be negligible or result in temporary community accommodation. Invasion events at moderate to high levels of the hierarchy permanently alter ecological communities, regional faunas, and global ecosystems. The prevalence of invasive species results in evolutionary changes by fostering niche evolution, differential survival of ecologically generalized taxa, faunal homogenization, and suppressing speciation. These impacts can contribute to mass extinctions and biodiversity crises that alter the trajectory of ecological and evolutionary patterns of life. The fossil record provides a long-term record of how invasion impacts may scale up through time, which can augment ecological studies of modern species invasions.

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Richardson, David M., et Petr Pyšek. « Plant invasions : merging the concepts of species invasiveness and community invasibility ». Progress in Physical Geography : Earth and Environment 30, n^o 3 (juillet 2006) : 409–31. http://dx.doi.org/10.1191/0309133306pp490pr.

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This paper considers key issues in plant invasion ecology, where findings published since 1990 have significantly improved our understanding of many aspects of invasions. The review focuses on vascular plants invading natural and semi-natural ecosystems, and on fundamental ecological issues relating to species invasiveness and community invasibility. Three big questions addressed by the SCOPE programme in the 1980s (which species invade; which habitats are invaded; and how can we manage invasions?) still underpin most work in invasion ecology. Some organizing and unifying themes in the field are organism-focused and relate to species invasiveness (the tens rule; the concept of residence time; taxonomic patterns and Darwin’s naturalization hypothesis; issues of phenotypic plasticity and rapid evolutionary change, including evolution of increased competitive ability hypothesis; the role of long-distance dispersal). Others are ecosystem-centred and deal with determinants of the invasibility of communities, habitats and regions (levels of invasion, invasibility and propagule pressure; the biotic resistance hypothesis and the links between diversity and invasibility; synergisms, mutualisms, and invasional meltdown). Some theories have taken an overarching approach to plant invasions by integrating the concepts of species invasiveness and community invasibility (a theory of seed plant invasiveness; fluctuating resources theory of invasibility). Concepts, hypotheses and theories reviewed here can be linked to the naturalization-invasion continuum concept, which relates invasion processes with a sequence of environmental and biotic barriers that an introduced species must negotiate to become casual, naturalized and invasive. New research tools and improved research links between invasion ecology and succession ecology, community ecology, conservation biology and weed science, respectively, have strengthened the conceptual pillars of invasion ecology.

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Cerwenka, Alexander F., Joerg Brandner, Dimitriy Dashinov et Juergen Geist. « Small but Mighty : The Round Goby (Neogobius melanostomus) as a Model Species of Biological Invasions ». Diversity 15, n^o 4 (6 avril 2023) : 528. http://dx.doi.org/10.3390/d15040528.

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Invasive “game-changer” species cause severe ecological impacts such as “phase shifts” in recipient ecosystems all over the world. Since the early 1990s, the ongoing global spread of the small but highly invasive Ponto-Caspian round goby Neogobius melanostomus into diverse freshwater and marine ecosystems has been observed. We postulate that this species is an ideal model to better understand and mitigate aquatic invasions. Its wide invaded range, as well as its diverse impacts on native species, have triggered a large body of research worldwide concerning its spread, ecology, and traits facilitating invasion. Several hypotheses related to invasiveness have been tested for the round goby, which are also applicable to other invasive species and for understanding general principles in invasion biology. However, a common theory explaining invasion success, especially in round goby, is still lacking. Many case studies do not consider time since invasion and use different sampling protocols and methodologies, hampering the comparability of results and conclusions. We thus propose strengthening the network of goby researchers and establishing long-term databases based on continuous and harmonized monitoring covering all stages of the invasion process as crucial requirements to better understand and manage aquatic invasions. In many cases, such monitoring can easily be integrated into existing survey schemes.

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Goldstein, Joshua, Jaewoo Park, Murali Haran, Andrew Liebhold et Ottar N. Bjørnstad. « Quantifying spatio-temporal variation of invasion spread ». Proceedings of the Royal Society B : Biological Sciences 286, n^o 1894 (9 janvier 2019) : 20182294. http://dx.doi.org/10.1098/rspb.2018.2294.

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— The spread of invasive species can have far-reaching environmental and ecological consequences. Understanding invasion spread patterns and the underlying process driving invasions are key to predicting and managing invasions. — We combine a set of statistical methods in a novel way to characterize local spread properties and demonstrate their application using simulated and historical data on invasive insects. Our method uses a Gaussian process fit to the surface of waiting times to invasion in order to characterize the vector field of spread. — Using this method, we estimate with statistical uncertainties the speed and direction of spread at each location. Simulations from a stratified diffusion model verify the accuracy of our method. — We show how we may link local rates of spread to environmental covariates for two case studies: the spread of the gypsy moth ( Lymantria dispar ), and hemlock woolly adelgid ( Adelges tsugae ) in North America. We provide an R-package that automates the calculations for any spatially referenced waiting time data.

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Sheppard, Christine S., et Marco R. Brendel. « Competitive ability of native and alien plants : effects of residence time and invasion status ». NeoBiota 65 (25 mai 2021) : 47–69. http://dx.doi.org/10.3897/neobiota.65.63179.

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Competition is commonly thought to underlie the impact of plant invasions. However, competitive effects of aliens and competitive response of natives may also change over time. Indeed, as with time, the novelty of an invader decreases, the accumulated eco-evolutionary experience of resident species may eventually limit invasion success. We aimed to gain insights on whether directional changes in biotic interactions over time or more general differences between natives and aliens, for instance, resulting from an introduction bias, are relevant in determining competitive ability. We conducted a pairwise competition experiment in a target-neighbour design, using 47 Asteraceae species with residence times between 8 years-12,000 years in Germany. We first tested whether there are differences in performance in intraspecific competition amongst invasion status groups, that is casual and established neophytes, archaeophytes or native species. We then evaluated whether competitive response and effects depend on residence time or invasion status. Lastly, we assessed whether competitive effects influence range sizes. We found only limited evidence that native target species tolerate neighbours with longer potential co-existence times better, whereas differences in competitive ability were mostly better explained by invasion status than residence time. Although casual neophytes produced most biomass in intraspecific competition, they had the weakest per-capita competitive effects on natives. Notably, we did not find differences between established neophytes and natives, both of which ranked highest in interspecific competitive ability. This lack of differences might be explained by a biased selection of highly invasive or rare native species in previous studies or because invasion success may result from mechanisms other than interspecific competitive superiority. Accordingly, interspecific per-capita competitive effects did not influence range sizes. Further studies across a broader range of environmental conditions, involving other biotic interactions that indirectly influence plant-plant interactions, may clarify when eco-evolutionary adaptations to new invaders are a relevant mechanism.

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JOHNSTONE, I. M. « PLANT INVASION WINDOWS : A TIME-BASED CLASSIFICATION OF INVASION POTENTIAL ». Biological Reviews 61, n^o 4 (novembre 1986) : 369–94. http://dx.doi.org/10.1111/j.1469-185x.1986.tb00659.x.

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Villarreal, Miguel, Christopher Soulard et Eric Waller. « Landsat Time Series Assessment of Invasive Annual Grasses Following Energy Development ». Remote Sensing 11, n^o 21 (30 octobre 2019) : 2553. http://dx.doi.org/10.3390/rs11212553.

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Invasive annual grasses are of concern in much of the western United States because they tolerate resource variability and have high reproductive capacity, with propagules that are readily dispersed in disturbed areas like those created and maintained for energy development. Early season invasive grasses “green up” earlier than most native plants, producing a distinct pulse of greenness in the early spring that can be exploited to identify their location using multi-date imagery. To determine if invasive annual grasses increased around energy developments after the construction phase, we calculated an invasives index using Landsat TM and ETM+ imagery for a 34-year time period (1985–2018) and assessed trends for 1755 wind turbines installed between 1988 and 2013 in the southern California desert. The index uses the maximum Normalized Difference Vegetation Index (NDVI) for early season greenness (January-June), and mean NDVI (July–October) for the later dry season. We estimated the relative cover of invasive annuals each year at turbine locations and control sites and tested for changes before and after each turbine was installed. The time series was also mapped across the region and temporal trends were assessed relative to seasonal precipitation. The results showed an increase in early season invasives at turbine sites after installation, but also an increase in many of the surrounding control areas. Maps of the invasive index show a region-wide increase starting around 1998, and much of the increase occurred in areas surrounding wind development sites. These results suggest that invasions around the energy developments occurred within the context of a larger regional invasion, and while the development did not necessarily initiate the invasion, annual grasses were more prevalent around the developments.

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Dutta, Dipanwita, Gang Chen, Chen Chen, Sara A. Gagné, Changlin Li, Christa Rogers et Christopher Matthews. « Detecting Plant Invasion in Urban Parks with Aerial Image Time Series and Residual Neural Network ». Remote Sensing 12, n^o 21 (24 octobre 2020) : 3493. http://dx.doi.org/10.3390/rs12213493.

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Invasive plants are a major agent threatening biodiversity conservation and directly affecting our living environment. This study aims to evaluate the potential of deep learning, one of the fastest-growing trends in machine learning, to detect plant invasion in urban parks using high-resolution (0.1 m) aerial image time series. Capitalizing on a state-of-the-art, popular architecture residual neural network (ResNet), we examined key challenges applying deep learning to detect plant invasion: relatively limited training sample size (invasion often confirmed in the field) and high forest contextual variation in space (from one invaded park to another) and over time (caused by varying stages of invasion and the difference in illumination condition). To do so, our evaluations focused on a widespread exotic plant, autumn olive (Elaeagnus umbellate), that has invaded 20 urban parks across Mecklenburg County (1410 km2) in North Carolina, USA. The results demonstrate a promising spatial and temporal generalization capacity of deep learning to detect urban invasive plants. In particular, the performance of ResNet was consistently over 96.2% using training samples from 8 (out of 20) or more parks. The model trained by samples from only four parks still achieved an accuracy of 77.4%. ResNet was further found tolerant of high contextual variation caused by autumn olive’s progressive invasion and the difference in illumination condition over the years. Our findings shed light on prioritized mitigation actions for effectively managing urban invasive plants.

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Gruntman, Michal, et Udi Segev. « Effect of residence time on trait evolution in invasive plants : review and meta-analysis ». NeoBiota 91 (22 février 2024) : 99–124. http://dx.doi.org/10.3897/neobiota.91.109251.

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The success of invasive species is often attributed to rapid post-introduction evolution, due to novel selection pressures at the introduced range. However, evolutionary shifts in invasion-promoting traits can also take place within the introduced range over time. Here, we first present a review of the proposed hypotheses regarding the selection pressures and trait divergence along gradients of invasion history and the studies that examined them. In addition, we present the results of a meta-analysis aimed to provide a more general overview of current knowledge on trait evolution with time since introduction. Invasion-promoting traits, including growth, competitive ability and dispersal ability, were proposed to decline in more established populations with a long invasion history due to the attenuation of selection pressures, such as enemy release or interspecific competition, while herbivore defence was suggested to increase. Our meta-analysis results reveal a general indication for the evolution of invasive plants with residence time for most of the studied traits. However, this divergence did not have a consistent direction in most traits, except for growth, which, in contrast with our prediction, increased with residence time. The lack of empirical support for the predicted change in most of the studied traits over time suggests trait evolution might be affected by other context-dependent factors such as climatic gradients along invasion routes. Similarly, the increased allocation to size in older and more established populations may be driven by increased conspecific competition pressure experienced in these populations. The general temporal effect found in our meta-analysis stresses the need to consider population age when comparing attributes of invasive plants between native and invasive ranges. Moreover, the increased size of invasive plants in older populations, suggests that the dominance of these plants might not attenuate with time since introduction, thus highlighting the need to further explore the long-term dynamics between invasive plants and their recipient native communities.

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Romanuk, Tamara N., Yun Zhou, Ulrich Brose, Eric L. Berlow, Richard J. Williams et Neo D. Martinez. « Predicting invasion success in complex ecological networks ». Philosophical Transactions of the Royal Society B : Biological Sciences 364, n^o 1524 (27 juin 2009) : 1743–54. http://dx.doi.org/10.1098/rstb.2008.0286.

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A central and perhaps insurmountable challenge of invasion ecology is to predict which combinations of species and habitats most effectively promote and prevent biological invasions. Here, we integrate models of network structure and nonlinear population dynamics to search for potential generalities among trophic factors that may drive invasion success and failure. We simulate invasions where 100 different species attempt to invade 150 different food webs with 15–26 species and a wide range (0.06–0.32) of connectance. These simulations yield 11 438 invasion attempts by non-basal species, 47 per cent of which are successful. At the time of introduction, whether or not the invader is a generalist best predicts final invasion success; however, once the invader establishes itself, it is best distinguished from unsuccessful invaders by occupying a lower trophic position and being relatively invulnerable to predation. In general, variables that reflect the interaction between an invading species and its new community, such as generality and trophic position, best predict invasion success; however, for some trophic categories of invaders, fundamental species traits, such as having the centre of the feeding range low on the theoretical niche axis (for non-omnivorous and omnivorous herbivores), or the topology of the food web (for tertiary carnivores), best predict invasion success. Across all invasion scenarios, a discriminant analysis model predicted successful and failed invasions with 76.5 per cent accuracy for properties at the time of introduction or 100 per cent accuracy for properties at the time of establishment. More generally, our results suggest that tackling the challenge of predicting the properties of species and habitats that promote or inhibit invasions from food web perspective may aid ecologists in identifying rules that govern invasions in natural ecosystems.

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Yang, Grace, Tian Wang, Peifang Ye et Xiaoyu Zhang. « Abstract 4141 : Quantitative measurement of 3D tumor spheroid invasion using live cell time-lapse imaging ». Cancer Research 84, n^o 6_Supplement (22 mars 2024) : 4141. http://dx.doi.org/10.1158/1538-7445.am2024-4141.

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Abstract 90% of the death of cancer individuals is related to cancer metastasis1. The invasion and migration of cancer cells into surrounding tissues and chambers is the first step of metastasis2. To have a better and more in-depth understanding of the pathophysiological activities involved in metastatic cancer, accurate and reliable methods for evaluating cell invasion are urgently needed. Compared to the 2D cell model, the 3D system mimics the natural physiological properties and conditions, such as structure, physiology, biological signals of living tissues, cell-matrix interactions4. In this study, we followed the commonly used protocol for 3D tumor invasion assay3 to generate spheroids in Ultra-Low-attachment (ULA) round bottom 96-well plate and subsequently embedded them in Matrigel® (5 mg/mL). After polymerization, the Matrigel that contains tumor spheroid was submerged in 100 μL cell culture media. The invasion of the 3D spheroid in the presence or absence of drug treatment was monitored and quantified using the brightfield and fluorescence live cell time-lapse image acquisition and image analysis functions of the Agilent xCELLigence RTCA eSight. The progress of spheroid invasion and the drug-inhibitory effects on tumor invasion were quantified by tracking and calculating the area of invasive protrusion from the spheroid. Our data show that 1) different types of cancer cells had different metastatic potentials demonstrated by the level of invadopodium extending into the Matrigel at desired time points; 2) the invasion of 3D HT1080 spheroid was inhibited by cytochalasin D (Cyto D), an inhibitor of actin polymerization, and GM6001, a potent broad-spectrum inhibitor of matrix metalloproteinases (MMP), in a dose-dependent manner; 3) Cyto D exhibited higher efficacy of inhibiting tumor invasion than GM6001. In summary, our approach by combining the 3D tumor spheroid invasion model with the RTCA eSight’s capability of live cell imaging and automatic quantification of the area of invasive protrusion can facilitate and enhance the development of new treatments at the preclinical stage in the future. Citation Format: Grace Yang, Tian Wang, Peifang Ye, Xiaoyu Zhang. Quantitative measurement of 3D tumor spheroid invasion using live cell time-lapse imaging [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4141.

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Iacarella, Josephine C., Phoebe S. Mankiewicz et Anthony Ricciardi. « Negative competitive effects of invasive plants change with time since invasion ». Ecosphere 6, n^o 7 (juillet 2015) : art123. http://dx.doi.org/10.1890/es15-00147.1.

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Prass, Marju, Satu Ramula, Miia Jauni, Heikki Setälä et D. Johan Kotze. « The invasive herb Lupinus polyphyllus can reduce plant species richness independently of local invasion age ». Biological Invasions 24, n^o 2 (28 octobre 2021) : 425–36. http://dx.doi.org/10.1007/s10530-021-02652-y.

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AbstractThe ecological impacts of invasive species may change or accumulate with time since local invasion, potentially inducing further changes in communities and the abiotic environment. Yet, time since invasion is rarely considered when investigating the ecological impacts of invasive non-native species. To examine the effect of time since invasion on the ecological impacts of Lupinus polyphyllus, a perennial nitrogen-fixing herb, we surveyed vascular plant communities in the presence and absence of L. polyphyllus in young, intermediate, and old semi-natural grassland sites (ca. 5, 10, 15 years representing both time since lupine invasion and plant community age). We analyzed vascular plant community composition, vascular plant species richness, and the cover of various ecological plant groups and L. polyphyllus. In contrast to our hypotheses, we found no change in the mean cover of L. polyphyllus (about 35%) with time since local invasion, and an ordination did not suggest marked changes in plant community composition. L. polyphyllus was associated with lower species richness in invaded plant communities but this effect did not change with time since invasion. Invaded plant communities were also associated with lower occurrence of generalist, oligotrophic (low-nutrient-adapted) and copiotrophic (nutrient-demanding) species but no temporal dynamics were detected. We conclude that even the intermediate cover of L. polyphyllus can reduce plant species richness, but the ecological impact caused by this invader might not dramatically change or accumulate with time since invasion.

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Strona, Giovanni, Corey J. A. Bradshaw, Pedro Cardoso, Nicholas J. Gotelli, Frédéric Guillaume, Federica Manca, Ville Mustonen et Luis Zaman. « Time-travelling pathogens and their risk to ecological communities ». PLOS Computational Biology 19, n^o 7 (27 juillet 2023) : e1011268. http://dx.doi.org/10.1371/journal.pcbi.1011268.

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Permafrost thawing and the potential ‘lab leak’ of ancient microorganisms generate risks of biological invasions for today’s ecological communities, including threats to human health via exposure to emergent pathogens. Whether and how such ‘time-travelling’ invaders could establish in modern communities is unclear, and existing data are too scarce to test hypotheses. To quantify the risks of time-travelling invasions, we isolated digital virus-like pathogens from the past records of coevolved artificial life communities and studied their simulated invasion into future states of the community. We then investigated how invasions affected diversity of the free-living bacteria-like organisms (i.e., hosts) in recipient communities compared to controls where no invasion occurred (and control invasions of contemporary pathogens). Invading pathogens could often survive and continue evolving, and in a few cases (3.1%) became exceptionally dominant in the invaded community. Even so, invaders often had negligible effects on the invaded community composition; however, in a few, highly unpredictable cases (1.1%), invaders precipitated either substantial losses (up to -32%) or gains (up to +12%) in the total richness of free-living species compared to controls. Given the sheer abundance of ancient microorganisms regularly released into modern communities, such a low probability of outbreak events still presents substantial risks. Our findings therefore suggest that unpredictable threats so far confined to science fiction and conjecture could in fact be powerful drivers of ecological change.

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Leung, Brian, et Nicholas E. Mandrak. « The risk of establishment of aquatic invasive species : joining invasibility and propagule pressure ». Proceedings of the Royal Society B : Biological Sciences 274, n^o 1625 (21 août 2007) : 2603–9. http://dx.doi.org/10.1098/rspb.2007.0841.

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Invasive species are increasingly becoming a policy priority. This has spurred researchers and managers to try to estimate the risk of invasion. Conceptually, invasions are dependent both on the receiving environment (invasibility) and on the ability to reach these new areas (propagule pressure). However, analyses of risk typically examine only one or the other. Here, we develop and apply a joint model of invasion risk that simultaneously incorporates invasibility and propagule pressure. We present arguments that the behaviour of these two elements of risk differs substantially—propagule pressure is a function of time, whereas invasibility is not—and therefore have different management implications. Further, we use the well-studied zebra mussel ( Dreissena polymorpha ) to contrast predictions made using the joint model to those made by separate invasibility and propagule pressure models. We show that predictions of invasion progress as well as of the long-term invasion pattern are strongly affected by using a joint model.

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Jin, Liang, Yongjian Gu, Ming Xiao, Jiakuan Chen et Bo Li. « The history of Solidago canadensis invasion and the development of its mycorrhizal associations in newly-reclaimed land ». Functional Plant Biology 31, n^o 10 (2004) : 979. http://dx.doi.org/10.1071/fp04061.

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This study examined the associations between an invasive alien plant (Solidago canadensis L.) and arbuscular mycorrhizal fungi (AMF) in relation to the invasion history of S. canadensis on Chongming Island, China. A significant positive correlation was found between invasion time and AMF colonisation rate. The total number of AMF species increased with increasing invasion time and was positively related to the number of plant species occurring in plant communities, suggesting that the invasion time and plant diversity influence the diversity of AMF species. The relative abundance of two dominant AMF species, Glomus mosseae and G. constrictum, varied systematically with invasion time. In dry habitats, the relative abundance of G. mosseae increased with the invasion time of S. canadensis, while that of G. constrictum decreased with the invasion time. However, these relationships did not exist in the wet habitats. Our results suggest that certain AMF species might have helped S. canadensis colonise newly-reclaimed habitats and that succession of belowground AMF communities may occur concomitantly with the development of the aboveground plant communities.

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Maslov, Sergei. « Time Directed Avalanches in Invasion Models ». Physical Review Letters 74, n^o 4 (23 janvier 1995) : 562–65. http://dx.doi.org/10.1103/physrevlett.74.562.

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Gao, Zhiyin, Sen Liu et Weide Li. « Biological control for predation invasion based on pair approximation ». Mathematical Biosciences and Engineering 19, n^o 10 (2022) : 10252–74. http://dx.doi.org/10.3934/mbe.2022480.

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<abstract> <p>Biological invasions have been paid more attention since invasive species may cause certain threats to local ecosystems. When biological control is adopted, selecting control species for effect better becomes the focus of latest studies. A food web system, with one native species, one invasive species as predator, and one introduced control species preying on both native and invasive species, is established based on pair approximation, in which the spatial landscape of biological invasion and control is concerned, and the local and global dispersal strategies of invasive species, in addition to the predation preferences of control species for native and invasive species, are considered. The influence of the initial density and initial spatial structures of the control species is investigated and the effects of control species releasing time are analyzed. Generally, the earlier the species introduction, the better the control effect, especially for invasive species dispersing globally. Interestingly, too low control species predation preference for native species can lead to unsuccessful introduction, while too much predation preference will have a weak control effect. The larger the control species predatory preference for invasive species is, the more conducive it is to biological control. The extinction of the invasive species is closely related to the initial density and concentration of the control species. This study gives some insights on selecting control species, its appropriate releasing time, and the density and spatial aggregation of it. Some real-life examples are elaborated on, which provides references for biological invasion control.</p> </abstract>

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Rocchini, Duccio, Veronica Andreo, Michael Förster, Carol Ximena Garzon-Lopez, Andrew Paul Gutierrez, Thomas W. Gillespie, Heidi C. Hauffe et al. « Potential of remote sensing to predict species invasions ». Progress in Physical Geography : Earth and Environment 39, n^o 3 (25 mars 2015) : 283–309. http://dx.doi.org/10.1177/0309133315574659.

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Understanding the causes and effects of species invasions is a priority in ecology and conservation biology. One of the crucial steps in evaluating the impact of invasive species is to map changes in their actual and potential distribution and relative abundance across a wide region over an appropriate time span. While direct and indirect remote sensing approaches have long been used to assess the invasion of plant species, the distribution of invasive animals is mainly based on indirect methods that rely on environmental proxies of conditions suitable for colonization by a particular species. The aim of this article is to review recent efforts in the predictive modelling of the spread of both plant and animal invasive species using remote sensing, and to stimulate debate on the potential use of remote sensing in biological invasion monitoring and forecasting. Specifically, the challenges and drawbacks of remote sensing techniques are discussed in relation to: i) developing species distribution models, and ii) studying life cycle changes and phenological variations. Finally, the paper addresses the open challenges and pitfalls of remote sensing for biological invasion studies including sensor characteristics, upscaling and downscaling in species distribution models, and uncertainty of results.

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Schneider, Lisa, Junnan Liu, Cheng Zhang, Anca Azoitei, Sabine Meessen, Xi Zheng, Catharina Cremer et al. « The Role of Interleukin-1-Receptor-Antagonist in Bladder Cancer Cell Migration and Invasion ». International Journal of Molecular Sciences 22, n^o 11 (30 mai 2021) : 5875. http://dx.doi.org/10.3390/ijms22115875.

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Background: The interleukin-1-receptor antagonist IL1RA (encoded by the IL1RN gene) is a potent competitive antagonist to interleukin-1 (IL1) and thereby is mainly involved in the regulation of inflammation. Previous data indicated a role of IL1RA in muscle-invasive urothelial carcinoma of the bladder (UCB) as well as an IL1-dependent decrease in tissue barrier function, potentially contributing to cancer cell invasion. Objective: Based on these observations, here we investigated the potential roles of IL1RA, IL1A, and IL1B in bladder cancer cell invasion in vitro. Methods: Cell culture, real-time impedance sensing, invasion assays (Boyden chamber, pig bladder model), qPCR, Western blot, ELISA, gene overexpression. Results: We observed a loss of IL1RA expression in invasive, high-grade bladder cancer cell lines T24, UMUC-3, and HT1197 while IL1RA expression was readily detectable in the immortalized UROtsa cells, the non-invasive bladder cancer cell line RT4, and in benign patient urothelium. Thus, we modified the invasive human bladder cancer cell line T24 to ectopically express IL1RA, and measured changes in cell migration/invasion using the xCELLigence Real-Time-Cell-Analysis (RTCA) system and the Boyden chamber assay. The real-time observation data showed a significant decrease of cell migration and invasion in T24 cells overexpressing IL1RA (T24-IL1RA), compared to cells harboring an empty vector (T24-EV). Concurrently, tumor cytokines, e.g., IL1B, attenuated the vascular endothelial barrier, which resulted in a reduction of the Cell Index (CI), an impedance-based dimensionless unit. This reduction could be reverted by the simultaneous incubation with IL1RA. Moreover, we used an ex vivo porcine organ culture system to evaluate cell invasion capacity and showed that T24-IL1RA cells showed significantly less invasive capacity compared to parental T24 cells or T24-EV. Conclusions: Taken together, our results indicate an inverse correlation between IL1RA expression and tumor cell invasive capacity and migration, suggesting that IL1RA plays a role in bladder carcinogenesis, while the exact mechanisms by which IL1RA influences tumor cells migration/invasion remain to be clarified in future studies. Furthermore, we confirmed that real-time impedance sensing and the porcine ex vivo organ culture methods are powerful tools to discover differences in cancer cell migration and invasion.

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Thewes, Sascha, Hilde-Kristin Reed, Christian Grosse-Siestrup, David A. Groneberg, Michael Meissler, Martin Schaller et Bernhard Hube. « Haemoperfused liver as an ex vivo model for organ invasion of Candida albicans ». Journal of Medical Microbiology 56, n^o 2 (1 février 2007) : 266–70. http://dx.doi.org/10.1099/jmm.0.46760-0.

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To study invasion of the human fungal pathogen Candida albicans, several infection models have been established. This study describes the successful establishment of an ex vivo haemoperfused liver as a model to study invasion of C. albicans. Perfused organs from pigs could be kept functional for up to 12 h. By comparing a non-invasive and invasive strain of C. albicans and by following a time course of invasion, it was shown that the invasion process in the perfused liver infection model is very similar to the in vivo situation after intraperitoneal infection of mice. The advantage of this set-up compared with other models of invasion is discussed.

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Patzkowsky, Mark E., et Steven M. Holland. « Diversity partitioning of a Late Ordovician marine biotic invasion : controls on diversity in regional ecosystems ». Paleobiology 33, n^o 2 (2007) : 295–309. http://dx.doi.org/10.1666/06078.1.

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Biotic invasions are a common feature of the fossil record, yet remarkably little is known about them, given their enormous potential to reveal the processes that regulate local and regional diversity over long time scales. We used additive diversity partitioning to examine how diversity structure changed as a result of a marine biotic invasion in tropical, shallow and deep subtidal environments spanning approximately 4 Myr in the Late Ordovician. The biotic invasion increased richness in the regional ecosystem by nearly 40%. Within-habitat turnover diversity accounts for most of the increase in richness, with between-habitat turnover diversity contributing a lesser amount. Increases in these components of diversity were accommodated by increased packing of species along a depth gradient and increased habitat heterogeneity. Diversity metrics that incorporate taxon abundance (Shannon information, Simpson's D) show similar patterns and reveal that many invading taxa were locally abundant and widespread in their occurrence. Extinction of incumbent taxa did not foster the invasion; rather the invasion appears to be linked to a regional or global warming event. Taken together, these observations indicate that these Late Ordovician marine communities were open to invasion and not saturated with species. Moreover, the increase in species diversity caused by the invasion was not ephemeral; instead it lasted for at least 1 Myr. Similar studies of other biotic invasions in the fossil record are necessary to determine (1) the factors, such as extinction of incumbents or resource limitation, that may facilitate or inhibit invasion in ancient ecosystems; (2) how local and regional ecosystems respond to invasion; and (3) the extent to which biotic invasions play a substantial role in ecosystem change through geologic time.

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Ziller, Sílvia R., Michele de Sá Dechoum, Raphaela Aparecida Duarte Silveira, Hugo Marques da Rosa, Marcelo Souza Motta, Leonardo Filipe da Silva, Beatriz Cunha Mello Oliveira et Rafael D. Zenni. « A priority-setting scheme for the management of invasive non-native species in protected areas ». NeoBiota 62 (15 octobre 2020) : 591–606. http://dx.doi.org/10.3897/neobiota.62.52633.

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Invasion by non-native species is one of the major threats to the conservation of biodiversity and to the provision of ecosystem services by protected areas. Invasive species often co-occur in protected areas, represented by sparse, isolated individuals or populations in different stages in the process of invasion. Species invasiveness, habitat invasibility and impact also differ between ecosystems, so the risk of invasion varies. Besides, prioritization is required due to constraints on time, financial and other resources. Priority-setting is therefore key to help protected area managers invest efforts on biological invasions that offer the best chances of producing large-scale positive results at the lowest cost possible. A priority-setting scheme for the control of invasive non-native species in natural areas is presented in this paper. The scheme, based on field observations of species occurrences, was applied to the Itatiaia National Park (Brazil). Priorities are calculated from a combination of three criteria attributed to each occurrence: species risk of invasion considering local ecosystems, invasion stage, and species frequency. Data collected in the field in the Itatiaia National Park were used to calculate priorities for 50 non-native species (six animals and 44 plants) in four locations in the Park. The highest priorities were attributed to species of high risk in an early stage of invasion occurring in one site, whereas a few widespread species of low risk were given lower priority. The scheme has proven functional for setting priorities for the control of non-native species in the Itatiaia National Park and in many other protected areas in Brazil.

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Edgerton, Elizabeth, Hsiao-Hsuan Wang, William E. Grant et Michael Masser. « Aquatic Plant Invasion and Management in Riverine Reservoirs : Proactive Management via a Priori Simulation of Management Alternatives ». Diversity 14, n^o 12 (14 décembre 2022) : 1113. http://dx.doi.org/10.3390/d14121113.

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Negative impacts from aquatic invasive plants in the United States include economic costs, loss of commercial and recreational use, and environmental damage. Simulation models are valuable tools for predicting the invasion potentials of species and for the management of existing infestations. We developed a spatially explicit, agent-based model representing the invasion, growth, and senescence of aquatic weeds as functions of day length, water temperature, water depth, and the response of aquatic weeds to biological control. As a case study to evaluate its potential utility, we parameterized the model to represent two historical invasions (1975–1983 and 2004–2007) of Hydrilla (Hydrilla verticillata (L. fil.) Royle) in Lake Conroe, Texas, USA, and their subsequent biological control using grass carp (Ctenopharyngodon idella). Results of several hypothetical alternative management schemes indicated that grass carp stocking densities needed to control Hydrilla infestation increased exponentially as the lag time between initial invasion and initial stocking increased, whereas stocking densities needed to control infestation decreased as the amount of time allowed to control the infestation increased. Predictions such as those produced by our model aid managers in developing proactive management plans for areas most likely to be invaded.

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Karmezi, Maria, Nikos Krigas et Maria D. Argyropoulou. « The Invasion and Long Naturalization of Solanum elaeagnifolium affects the Soil Nematode Community : Evidence from a Comparative Study ». Agronomy 12, n^o 10 (29 septembre 2022) : 2346. http://dx.doi.org/10.3390/agronomy12102346.

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To date, the effects of invasive plants on soil communities and the concomitant interactions thereof have been the subject of ever-growing concern. Solanum elaeagnifolium (S) is a noxious invasive weed originating from south-central America, which has been recognized as a serious threat around the Mediterranean basin and worldwide. Herein, we compared soil nematode communities in the rhizospheres of (S), against those of its native antagonist Cichorium intybus (C), in sites where these two ruderal plants coexist (“species” effect—hereafter “sp”). These sites differed regarding the time after the initial invasion of (S) and were regarded as recently and historically invaded (10 years and 70 years after invasion; “year” effect—hereafter “yr”). Neither “sp” nor “yr” affected total nematode abundance and nematode functional indices. Diversity was lower in (S) and was reduced even more with time after invasion in both plant species. Plant parasites decreased significantly from S–10yr to S–70yr, i.e., over time after invasion, while predators were fewer in (C). Distinct nematode communities in terms of genera structure were formed under the two plant species and these were significantly affected by the time after (S) invasion. Differences between these communities related to loss of genera but also to changes in the abundance of common ones, such as Acrobeloides and Pratylenchus. Our results showed that the responses of the examined soil communities to the invasion of (S) are not straightforward and cannot be easily explained on the basis of existing theories. However, the first-time results furnished herein may be useful to integrated management strategies in the future.

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Olawoyin, Omomayowa, et Christopher Kribs. « Invasion reproductive numbers for discrete-time models ». Infectious Disease Modelling 4 (2019) : 44–72. http://dx.doi.org/10.1016/j.idm.2019.03.002.

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Hira, Vashendriya VV, Barbara Breznik, Cornelis JF Van Noorden, Tamara Lah et Remco J. Molenaar. « 2D and 3D in vitro assays to quantify the invasive behavior of glioblastoma stem cells in response to SDF-1α ». BioTechniques 69, n^o 5 (novembre 2020) : 339–46. http://dx.doi.org/10.2144/btn-2020-0046.

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Invasion is a hallmark of cancer and therefore in vitro invasion assays are important tools in cancer research. We aimed to describe in vitro 2D transwell assays and 3D spheroid assays to quantitatively determine the invasive behavior of glioblastoma stem cells in response to the chemoattractant SDF-1α. Matrigel was used as a matrix in both assays. We demonstrated quantitatively that SDF-1α increased invasive behavior of glioblastoma stem cells in both assays. We conclude that the 2D transwell invasion assay is easy to perform, fast and less complex whereas the more time-consuming 3D spheroid invasion assay is physiologically closer to the in vivo situation.

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Kowarik, Ingo. « Historical evidence for context-dependent assessment of Erigeron canadensis invasions in an 18th-century European landscape ». NeoBiota 89 (30 octobre 2023) : 1–15. http://dx.doi.org/10.3897/neobiota.89.111268.

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Understanding the historical roots of invasion science provides insights into early perceptions of invasive species, allows us to trace the evolution of the discipline over time, and helps contextualize modern research. This paper analyzes work by Christian Ludwig Krause, published 250 years ago, on the invasion of an 18th-century European landscape by Erigeron [Conyza] canadensis (Canadian horseweed), one of the most common invasive species today and a widespread agricultural weed. Here an analysis is conducted of the ecological consequences and underlying mechanisms Krause described, how he evaluated E. canadensis invasions in different land-use systems and how his insights align with existing knowledge. Krause identified copious seed production and long-distance dispersal by wind as key mechanisms for the formation of dominant stands on degraded sandy soils. He recognized various ecosystem services associated with population establishment, such as erosion control, increased soil fertility, and the facilitation of other species. While Krause highlighted the benefits of E. canadensis invasions for the recovery of degraded grasslands and fields, he also acknowledged this introduced species as a troublesome weed in gardens. Thus, Krause’s work is not only an early report on the invasion of a cultural landscape subject to wind erosion but also an early example of a context-dependent invasion assessment, illustrating both positive and negative impacts of the same species in different environments. Krause’s perspective may encourage current assessments of E. canadensis not solely based on its presence or frequency, but on documented ecological and socioeconomic effects and their associated benefits or harms. As Krause impressively demonstrated 250 years ago, these effects can differ starkly in different environments, necessitating multiple responses to the same species.

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Brodin, Tomas, et Marcus K. Drotz. « Individual variation in dispersal associated behavioral traits of the invasive Chinese mitten crab (Eriocheir sinensis, H. Milne Edwards, 1854) during initial invasion of Lake Vänern, Sweden ». Current Zoology 60, n^o 3 (1 juin 2014) : 410–16. http://dx.doi.org/10.1093/czoolo/60.3.410.

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Abstract Understanding and predicting species range-expansions and biological invasions is an important challenge in modern ecology because of rapidly changing environments. Recent studies have revealed that consistent within-species variation in behavior (i.e. animal personality) can be imperative for dispersal success, a key stage in the invasion process. Here we investigate the composition and correlation of two important personality traits associated with invasion success, activity and boldness, and how they are connected to sex and individual size in a newly colonised population of the Chinese mitten crab Eriocheir sinensis in Lake Vänern, Sweden. We found no effect of sex or size on behavioral expressions of E. sinensis but a clear positive correlation between boldness and activity. In addition, this study generates important baseline data for monitoring behavioral development, and thereby changing ecological impact, of an invading population over time. This has implications for predicting ecological effects of invasive species as well as for managing ecological invasions.

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Patzkowsky, Mark E., et Steven M. Holland. « Biotic invasion, niche stability, and the assembly of regional biotas in deep time : comparison between faunal provinces ». Paleobiology 42, n^o 3 (28 avril 2016) : 359–79. http://dx.doi.org/10.1017/pab.2016.1.

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AbstractBiotic invasions in the fossil record provide natural experiments for testing hypotheses of niche stability, speciation, and the assembly and diversity of regional biotas. We compare ecological parameters (preferred environment, occupancy, median abundance, rank abundance) of genera shared between faunal provinces during the Richmondian Invasion in the Late Ordovician on the Laurentian continent. Genera that spread from one faunal province to the other during the invasion (invading shared genera) have high Spearman rank correlations (>0.5) in three of four ecological parameters, suggesting a high level of niche stability among invaders. Genera that existed in both regions prior to and following the invasion (noninvading shared genera) have low correlations (<0.3) and suggest niche shift between lineages that diverged at least 8 Myr earlier. Niche shift did not accumulate gradually over this time interval but appears to have occurred in a pulse associated with the onset of the Taconic orogeny and the switch from warm-water to cool-water carbonates in southern Laurentia.

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Kourantidou, Melina, Ross N. Cuthbert, Phillip J. Haubrock, Ana Novoa, Nigel G. Taylor, Boris Leroy, César Capinha et al. « Economic costs of invasive alien species in the Mediterranean basin ». NeoBiota 67 (29 juillet 2021) : 427–58. http://dx.doi.org/10.3897/neobiota.67.58926.

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Invasive alien species (IAS) negatively impact the environment and undermine human well-being, often resulting in considerable economic costs. The Mediterranean basin is a culturally, socially and economically diverse region, harbouring many IAS that threaten economic and societal integrity in multiple ways. This paper is the first attempt to collectively quantify the reported economic costs of IAS in the Mediterranean basin, across a range of taxonomic, temporal and spatial descriptors. We identify correlates of costs from invasion damages and management expenditures among key socioeconomic variables, and determine network structures that link countries and invasive taxonomic groups. The total reported invasion costs in the Mediterranean basin amounted to $27.3 billion, or $3.6 billion when only realised costs were considered, and were found to have occurred over the last three decades. Our understanding of costs of invasions in the Mediterranean was largely limited to a few, primarily western European countries and to terrestrial ecosystems, despite the known presence of numerous high-impact aquatic invasive taxa. The vast majority of costs were attributed to damages or losses from invasions ($25.2 billion) and were mostly driven by France, Spain and to a lesser extent Italy and Libya, with significantly fewer costs attributed to management expenditure ($1.7 billion). Overall, invasion costs increased through time, with average annual costs between 1990 and 2017 estimated at $975.5 million. The lack of information from a large proportion of Mediterranean countries, reflected in the spatial and taxonomic connectivity analysis and the relationship of costs with socioeconomic variables, highlights the limits of the available data and the research effort needed to improve a collective understanding of the different facets of the costs of biological invasions. Our analysis of the reported costs associated with invasions in the Mediterranean sheds light on key knowledge gaps and provides a baseline for a Mediterranean-centric approach towards building policies and designing coordinated responses. In turn, these could help reach socially desirable outcomes and efficient use of resources invested in invasive species research and management.

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Sarnow, Katharina, Georgia Kanli, Olivier Keunen et Rolf Bjerkvig. « TAMI-24. INHIBITION OF GBM INVASION BY THE Α-AMINO-3-HYDROXY-5-METHYL-4-ISOXAZOLEPROPIONIC ACID (AMPA) GLUTAMATE RECEPTOR ANTAGONIST PERAMPANEL ». Neuro-Oncology 23, Supplement_6 (2 novembre 2021) : vi203. http://dx.doi.org/10.1093/neuonc/noab196.808.

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Abstract BACKGROUND Extensive tumor cell invasion within the brain represents a major problem for effective treatment of glioblastomas (GBMs). The invasive processes can be divided into three types: Collective cell invasion, perivascular infiltration, and single-cell invasion into the brain parenchyma. GBM cells can form synapses with neural cells pointing at an extensive communication network between brain and GBM cells which can be mediated via the metabolites Glutamine and Glutamate both needed for GBM cell proliferation. In this context, it has been shown in preclinical models that Perampanel, an antiepileptic agent, functioning as non-competitive α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) glutamate receptor antagonist, has an inhibitory effect on GBM growth. To delineate how Perampanel affects GBM invasion, we utilised a highly characterized 3D GBM-brain organoid invasion model where single-cell invasion was studied in real-time following Perampanel treatment. METHODS A brain coculture model, consisting of rat brain organoids expressing various markers of the human adult brain, where confronted with GFP-labelled tumor cells. By using time-lapse confocal microscopy, we quantified single-cell invasion patterns and speed of invasion using two glioma stem cell models (BG5 and BG7). RESULTS Perampanel treatment significantly reduces tumor cell invasion into the brain organoids with the strongest effect seen in the most invasive GBM (BG5). The single-tumor cell invasion ratio was reduced by 72 % compared to the control (p= 0.0033). In contrast, collective cell invasion was reduced by 19 % (p= 0.028). Statistical analysis was performed using an unpaired sample t-test. CONCLUSION The AMPA glutamate receptor antagonist Perampanel significantly inhibits GBM invasion, suggesting an important role of the glutamate-glutamine cycle between the GBM cells and neurons in the invasion process. Moreover, this communication and exchange of metabolites seem to be more prominent where single GBM cells invade into the brain parenchyma compared to areas where collective invasion take place.

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Sarnow, K., G. Kanli, O. Keunen et R. Bjerkvig. « OS06.6A Inhibition of GBM invasion by the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) glutamate receptor antagonist Perampanel ». Neuro-Oncology 23, Supplement_2 (1 septembre 2021) : ii10. http://dx.doi.org/10.1093/neuonc/noab180.030.

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Abstract BACKGROUND Extensive tumor cell invasion within the brain represents a major problem for effective treatment of glioblastomas (GBMs). The invasive processes can be divided into three types: Collective cell invasion, perivascular infiltration and single-cell invasion into the brain parenchyma. It has recently been shown that GBM cells have the ability to form synapses with neural cells pointing at an extensive communication network between brain cells GBM cells. This communication network can be mediated via the metabolites glutamine and glutamate both needed for GBM cell proliferation. In this context, it has been shown in preclinical models that Perampanel, an antiepileptic agent, functioning as non-competitive α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) glutamate receptor antagonist, has an inhibitory effect on GBM growth. In order to delineate how Perampanel affects GBM invasion, we here utilised a highly characterized 3D GBM-brain organoid invasion model where single-cell invasion was studied in real-time following Perampanel treatment. MATERIAL AND METHODS A brain coculture model, consisting of rat brain organoids expressing various markers of the human adult brain, where confronted with GFP-labelled tumor cells. By using time-lapse confocal microscopy, we quantified single-cell invasion patterns and speed of invasion using two glioma stem cell models (GSCs; BG5 and BG7). RESULTS Perampanel treatment significantly reduces tumor cell invasion into the brain organoids with the strongest effect seen in the most invasive GBM (BG5). Here, the single-tumor cell invasion ratio was reduced by 72 % compared to the control group (p=0.0033). In contrast, collective cell invasion was reduced by 19 % (p=0.028). Statistical analysis was performed using an unpaired sample t-test. CONCLUSION The AMPA glutamate receptor antagonist Perampanel significantly inhibits GBM invasion, suggesting an important role of the glutamate-glutamine cycle between the GBM cells and neurons in the invasion process. Moreover, this communication and exchange of metabolites seems to be more prominent where single GBM cells invade into the brain parenchyma compared to areas where collective invasion take place.

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Sathianathen, Niranjan J., Marc A. Furrer, Clancy J. Mulholland, Andreas Katsios, Christopher Soliman, Nathan Lawrentschuk, Justin S. Peters et al. « Lymphovascular Invasion at the Time of Radical Prostatectomy Adversely Impacts Oncological Outcomes ». Cancers 16, n^o 1 (26 décembre 2023) : 123. http://dx.doi.org/10.3390/cancers16010123.

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Lymphovascular invasion, whereby tumour cells or cell clusters are identified in the lumen of lymphatic or blood vessels, is thought to be an essential step in disease dissemination. It has been established as an independent negative prognostic indicator in a range of cancers. We therefore aimed to assess the impact of lymphovascular invasion at the time of prostatectomy on oncological outcomes. We performed a multicentre, retrospective cohort study of 3495 men who underwent radical prostatectomy for localised prostate cancer. Only men with negative preoperative staging were included. We assessed the relationship between lymphovascular invasion and adverse pathological features using multivariable logistic regression models. Kaplan–Meier curves and Cox proportional hazard models were created to evaluate the impact of lymphovascular invasion on oncological outcomes. Lymphovascular invasion was identified in 19% (n = 653) of men undergoing prostatectomy. There was an increased incidence of lymphovascular invasion-positive disease in men with high International Society of Urological Pathology (ISUP) grade and non-organ-confined disease (p < 0.01). The presence of lymphovascular invasion significantly increased the likelihood of pathological node-positive disease on multivariable logistic regression analysis (OR 15, 95%CI 9.7–23.6). The presence of lymphovascular invasion at radical prostatectomy significantly increased the risk of biochemical recurrence (HR 2.0, 95%CI 1.6–2.4). Furthermore, lymphovascular invasion significantly increased the risk of metastasis in the whole cohort (HR 2.2, 95%CI 1.6–3.0). The same relationship was seen across D’Amico risk groups. The presence of lymphovascular invasion at the time of radical prostatectomy is associated with aggressive prostate cancer disease features and is an indicator of poor oncological prognosis.

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Corli et Sheppard. « Effects of Residence Time, Auto-Fertility and Pollinator Dependence on Reproductive Output and Spread of Alien and Native Asteraceae ». Plants 8, n^o 4 (23 avril 2019) : 108. http://dx.doi.org/10.3390/plants8040108.

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Alien plants benefit from auto-fertility to spread over areas where the lack of co-evolved mutualists would otherwise limit invasion success. However, the widespread generalists among mutualists and their large geographical ranges allow alien plants to be integrated into networks. The role of residence time also has to be accounted for, as it takes time for a species to spread and adapt to a new area. We investigated how residence time, auto-fertility and pollinator dependence affect reproductive output and invasion success of Asteraceae in Germany. We conducted a multi-species common-garden experiment along an alien–native continuum including 42 species of natives, archaeophytes and neophytes (casual and established), subjecting plant individuals either to free access or exclusion of pollinators. Pollinator dependence does not play a crucial role in invasion success, with most Asteraceae being able to self-fertilize. Surprisingly, both established neophytes and natives showed higher abilities to self-fertilize, while archaeophytes and casual neophytes were more attractive to pollinators. In contrast to casual neophytes, the established neophytes’ strategy was associated with a large reproductive output. Yet, auto-fertility was not associated with range size, since archaeophytes reached the largest range sizes. Elucidating how breeding systems affect invasion success is crucial for predicting and managing invasions.

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Haubrock, Phillip J., Ross N. Cuthbert, Andrea Sundermann, Christophe Diagne, Marina Golivets et Franck Courchamp. « Economic costs of invasive species in Germany ». NeoBiota 67 (29 juillet 2021) : 225–46. http://dx.doi.org/10.3897/neobiota.67.59502.

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Invasive alien species are a well-known and pervasive threat to global biodiversity and human well-being. Despite substantial impacts of invasive alien species, quantitative syntheses of monetary costs incurred from invasions in national economies are often missing. As a consequence, adequate resource allocation for management responses to invasions has been inhibited, because cost-benefit analysis of management actions cannot be derived. To determine the economic cost of invasions in Germany, a Central European country with the 4th largest GDP in the world, we analysed published data collected from the first global assessment of economic costs of invasive alien species. Overall, economic costs were estimated at US$ 9.8 billion between 1960 and 2020, including US$ 8.9 billion in potential costs. The potential costs were mostly linked to extrapolated costs of the American bullfrog Lithobates catesbeianus, the black cherry Prunus serotina and two mammals: the muskrat Ondatra zibethicus and the American mink Neovison vison. Observed costs were driven by a broad range of taxa and mostly associated with control-related spending and resource damages or losses. We identified a considerable increase in costs relative to previous estimates and through time. Importantly, of the 2,249 alien and 181 invasive species reported in Germany, only 28 species had recorded economic costs. Therefore, total quantifications of invasive species costs here should be seen as very conservative. Our findings highlight a distinct lack of information in the openly-accessible literature and governmental sources on invasion costs at the national level, masking the highly-probable existence of much greater costs of invasions in Germany. In addition, given that invasion rates are increasing, economic costs are expected to further increase. The evaluation and reporting of economic costs need to be improved in order to deliver a basis for effective mitigation and management of invasions on national and international economies.

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Pyšek, Petr, Sven Bacher, Ingolf Kühn, Ana Novoa, Jane A. Catford, Philip E. Hulme, Jan Pergl, David M. Richardson, John R. U. Wilson et Tim M. Blackburn. « MAcroecological Framework for Invasive Aliens (MAFIA) : disentangling large-scale context dependence in biological invasions ». NeoBiota 62 (15 octobre 2020) : 407–61. http://dx.doi.org/10.3897/neobiota.62.52787.

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Macroecology is the study of patterns, and the processes that determine those patterns, in the distribution and abundance of organisms at large scales, whether they be spatial (from hundreds of kilometres to global), temporal (from decades to centuries), and organismal (numbers of species or higher taxa). In the context of invasion ecology, macroecological studies include, for example, analyses of the richness, diversity, distribution, and abundance of alien species in regional floras and faunas, spatio-temporal dynamics of alien species across regions, and cross-taxonomic analyses of species traits among comparable native and alien species pools. However, macroecological studies aiming to explain and predict plant and animal naturalisations and invasions, and the resulting impacts, have, to date, rarely considered the joint effects of species traits, environment, and socioeconomic characteristics. To address this, we present the MAcroecological Framework for Invasive Aliens (MAFIA). The MAFIA explains the invasion phenomenon using three interacting classes of factors – alien species traits, location characteristics, and factors related to introduction events – and explicitly maps these interactions onto the invasion sequence from transport to naturalisation to invasion. The framework therefore helps both to identify how anthropogenic effects interact with species traits and environmental characteristics to determine observed patterns in alien distribution, abundance, and richness; and to clarify why neglecting anthropogenic effects can generate spurious conclusions. Event-related factors include propagule pressure, colonisation pressure, and residence time that are important for mediating the outcome of invasion processes. However, because of context dependence, they can bias analyses, for example those that seek to elucidate the role of alien species traits. In the same vein, failure to recognise and explicitly incorporate interactions among the main factors impedes our understanding of which macroecological invasion patterns are shaped by the environment, and of the importance of interactions between the species and their environment. The MAFIA is based largely on insights from studies of plants and birds, but we believe it can be applied to all taxa, and hope that it will stimulate comparative research on other groups and environments. By making the biases in macroecological analyses of biological invasions explicit, the MAFIA offers an opportunity to guide assessments of the context dependence of invasions at broad geographical scales.

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Maxwell, Bruce D., Erik Lehnhoff et Lisa J. Rew. « The Rationale for Monitoring Invasive Plant Populations as a Crucial Step for Management ». Invasive Plant Science and Management 2, n^o 1 (janvier 2009) : 1–9. http://dx.doi.org/10.1614/ipsm-07-054.1.

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AbstractMany land managers are faced with trying to optimize management of invasive plant species based on budget constraints and lack of knowledge of the true potential of the species. Generally, “early detection rapid response” (EDRR) is the assumed best management strategy and tends to drive management regardless of the invasion stage or possible variation in the invasion potential of the population. We created a simulation model to evaluate the optimal management strategy to reduce the rate of invasion of nonindigenous plant species. The strategies were specifically chosen to assess the value of information from monitoring populations. We compared four management strategies and a no-management control over a 20-yr period in the context of a management area: (1) managing a fixed number of populations at random each year (EDRR random), (2) managing an equivalent number of populations along a road each year (EDRR road), (3) managing half of the fixed populations that were determined by monitoring to be sources of new populations (monitoring every year), and (4) managing an equivalent set of source populations only on even years, leaving the odd years for monitoring (monitoring every other year). EDRR random location without regard to population invasion potential, and monitoring every year targeting management on populations determined to be invasive (sources for new populations), were the most successful strategies for reducing the increase in total number of populations. The model simulations suggest that managers could dedicate 50% of their management time to monitoring without risk of accelerating invasions or reducing the impact of their weed management program.

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Nerodo, Galina, Victoria Aleksandrovna Ivanova et Ekaterina Alekseevna Nerodo. « Time to vulva cancer relapses in dependence on different factors. » Journal of Clinical Oncology 31, n^o 15_suppl (20 mai 2013) : e16513-e16513. http://dx.doi.org/10.1200/jco.2013.31.15_suppl.e16513.

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e16513 Background: The time to relapses was investigated in dependence on different factors. Methods: We examined 809 vulva cancer patients to evaluate frequency and average time to relapse depending on grades, invasion depth and method of treatment. Results: We found out that 25.09% (203 from 809) of patients had a relapse. For the I grade the relapse was observed in 18.29% patients after 59.3 months on average, for the II grade – in 20.5% after 46.9 months, for the III grade – in 26.6% after 16.8 months, for the IV grade – in 46.2% patients after 7.2 months respectively. The patients of the II grade with tumor invasion of 1-2 mm had a relapse after 61.2 months, with invasion of 3-4 mm – after 42.1, with more than 5 mm – after 38.5 months on average correspondingly. For patients of the III grade with tumor invasion less than 5 mm the average time to relapse was 19.9 months, with invasion more than 5 mm – 12.6 months. There is not significant difference between the times to relapses of early grades patients treated with combined method or complex method with chemotherapy. However for the patients of the III grade the chemotherapy has prolonged the time to relapse from 13.5 to 18.1 months. Conclusions: The relapses of vulva cancer were observed in 25.09% of all patients. The grade, depth of invasion and chemotherapy as a part of complex treatment of III-IV grades patients have considerable influence on the time to relapse.

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Savić, Aleksandra, Maor Matzrafi, Sanja Đurović, Rodolfo Gentili et Sandra Citterio. « Is Ambrosia trifida L. Preparing for a Wider Invasion ? Changes in the Plant Morpho-Functional Traits over a Decade ». Agronomy 14, n^o 8 (23 juillet 2024) : 1601. http://dx.doi.org/10.3390/agronomy14081601.

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Plastic traits are argued to favor the establishment of invasive alien plants and to evolve during the invasion process, so that invasions may be favored by both plasticity and evolutionary changes in plasticity. Despite this aspect being pivotal to understanding invasion processes, no information is available about the effect of residence time on the evolution of phenotypic plasticity of aliens to produce locally adapted phenotypes. Therefore, we aimed to evaluate changes in the morpho-functional traits of the invasive alien Ambrosia trifida L. over time. Specifically, we grew A. trifida plants under laboratory (at different temperatures: 10 °C, 20 °C and 25 °C) and field conditions by using seeds collected from 2011 to 2020 from an Eastern European population. Data about seedling emergence, vegetative (laboratory and field) and reproductive (field) traits were collected, e.g., maximum plant height (cm), total dry biomass (g), number of flowers (n) and number of new seeds (n). Analysis of variance (ANOVA), linear regressions and a plasticity index were applied to assess differences in plant performances when grown from seeds of different ages. An auto-regressive integrated moving average (ARIMA) model was applied to predict future trends of some key plant traits (maximum height, total dry biomass and number of new seeds). Overall, the time of seedling emergence was not statistically different among seeds of different age, and regression analyses exhibited a positive relationship between residence time (seed age) and vegetative and reproductive parameters of A. trifida. Only male flower production exhibited a negative trend over time. At all temperatures (especially at 25 °C), the vegetative parameters increased with the decrease in residence time. The plasticity index of the measured traits tended to decrease over time for most traits both in the field and in the laboratory trials. The ARIMA model predicted that plant traits will continue to increase in size over time by 2030, suggesting further plastic adaptation of A. trifida. The results highlighted that residence time influences the evolution of phenotypic plasticity of A. trifida, which has strengthened its adaptability to the new conditions over a decade, also demonstrating a great adaptive and invasion potential for the future.

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Suwannakul, S., G. P. Stafford, S. A. Whawell et C. W. I. Douglas. « Identification of bistable populations of Porphyromonas gingivalis that differ in epithelial cell invasion ». Microbiology 156, n^o 10 (1 octobre 2010) : 3052–64. http://dx.doi.org/10.1099/mic.0.038075-0.

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Bistable populations of bacteria give rise to two or more subtypes that exhibit different phenotypes. We have explored whether the periodontal pathogen Porphyromonas gingivalis exhibits bistable invasive phenotypes. Using a modified cell invasion assay, we show for the first time that there are two distinct subtypes within a population of P. gingivalis strains NCTC 11834 and W50 that display differences in their ability to invade oral epithelial cells. The highly invasive subtype invades cells at 10–30-fold higher levels than the poorly invasive subtype and remains highly invasive for approximately 12–16 generations. Analysis of the gingipain activity of these subtypes revealed that the highly invasive type had reduced cell-associated arginine-specific protease activity. The role of Arg-gingipain activity in invasion was verified by enhancement of invasion by rgpAB mutations and by inclusion of an Arg-gingipain inhibitor in invasion assays using wild-type bacteria. In addition, a population of ΔrgpAB bacteria did not contain a hyperinvasive subtype. Screening of the protease activity of wild-type populations of both strains identified high and low protease subtypes which also showed a corresponding reduction or enhancement, respectively, of invasive capabilities. Microarray analysis of these bistable populations revealed a putative signature set of genes that includes oxidative stress resistance and iron transport genes, and which might be critical to invasion of or survival within epithelial cells.

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Vinson, John E., et Andrew W. Park. « Vector-borne parasite invasion in communities across space and time ». Proceedings of the Royal Society B : Biological Sciences 286, n^o 1917 (18 décembre 2019) : 20192614. http://dx.doi.org/10.1098/rspb.2019.2614.

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While vector-borne parasite transmission often operates via generalist-feeding vectors facilitating cross-species transmission in host communities, theory describing the relationship between host species diversity and parasite invasion in these systems is underdeveloped. Host community composition and abundance vary across space and time, generating opportunities for parasite invasion. To explore how host community variation can modify parasite invasion potential, we develop a model for vector-borne parasite transmission dynamics that includes a host community of arbitrary richness and species' abundance. To compare invasion potential across communities, we calculate the community basic reproductive ratio of the parasite. We compare communities comprising a set of host species to their subsets, which allows for flexible scenario building including the introduction of novel host species and species loss. We allow vector abundance to scale with, or be independent of, community size, capturing regulation by feeding opportunities and non-host effects such as limited oviposition sites. Motivated by equivocal data relating host species competency to abundance, we characterize plausible host communities via phenomenological relationships between host species abundance and competency. We identify an underappreciated mechanism whereby changes to communities simultaneously alter average competency and the vector to host ratio and demonstrate that the interaction can profoundly influence invasion potential.

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Ng, York Hunt, Hua Zhu et Peter C. K. Leung. « Twist Modulates Human Trophoblastic Cell Invasion via Regulation of N-Cadherin ». Endocrinology 153, n^o 2 (1 février 2012) : 925–36. http://dx.doi.org/10.1210/en.2011-1488.

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The invasion of extravillous cytotrophoblasts (EVT) into the underlying maternal tissues and vasculature is a key step in human placentation. The molecular mechanisms involved in the development of the invasive phenotype of EVT include many that were first discovered for their role in cancer cell metastasis. Previous studies have demonstrated that N-cadherin and its regulatory transcription factor Twist play important roles in the onset and progression of cancers, but their roles in human trophoblastic cell invasion is not clear. The goal of the study was to examine the role of Twist and N-cadherin in human trophoblastic cell invasion. Twist and N-cadherin mRNA and protein levels were determined by RT-PCR and Western blotting in human placental tissues, highly invasive EVT, and poorly invasive JEG-3 and BeWo cells. Whether IL-1β and TGF-β1 regulate Twist mRNA and protein levels in the EVT was also examined. A small interfering RNA strategy was employed to determine the role of Twist and N-cadherin in HTR-8/SVneo cell invasion. Matrigel assays were used to assess cell invasion. Twist and N-cadherin were highly expressed in EVT but were poorly expressed in JEG-3 and BeWo cells. IL-1β and TGF-β1 differentially regulated Twist expression in EVT in a time- and concentration-dependent manner. Small interfering RNA specific for Twist decreased N-cadherin and reduced invasion of HTR-8/SVneo cells. Similarly, a reduction in N-cadherin decreased the invasive capacity of HTR-8/SVneo cells. Twist is an upstream regulator of N-cadherin-mediated invasion of human trophoblastic cells.

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THOMAZ, SIDINEI M., ANGELO A. AGOSTINHO, LUIZ C. GOMES, MÁRCIO J. SILVEIRA, MARCEL REJMÁNEK, CLARE E. ASLAN et ELAINE CHOW. « Using space-for-time substitution and time sequence approaches in invasion ecology ». Freshwater Biology 57, n^o 11 (10 septembre 2012) : 2401–10. http://dx.doi.org/10.1111/fwb.12005.

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Liu, Chang, Li-Qian Xuan, Kai Li, Zhuo Feng, Chan Lv, Xing-Jia Li, Xiao-Dan Ji, Rong Wan et Jie Shen. « Shikonin Inhibits Cholangiocarcinoma Cell Line QBC939 by Regulating Apoptosis, Proliferation, and Invasion ». Cell Transplantation 30 (1 janvier 2021) : 096368972097916. http://dx.doi.org/10.1177/0963689720979162.

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This study was designed to clarify whether Shikonin causes proliferation, apoptosis, and invasion in cholangiocarcinoma cells and to investigate the mechanism of action. QBC939 cells were cultured with different doses of Shikonin, and then 3-(4,5-dimethylthiazol-2-yl) -2,5-diphenyltetrazolium assay was used to detect cell viability. Apoptosis of cells was detected using flow cytometry with Annexin V/propidium iodide (PI) assay after being stained with Hoechst 33242. The role of Shikonin on the invasive and metastasis ability was detected using Transwell invasion assay. Real-time polymerase chain reaction and Western blotting were used to detect the expression of caspase-3, caspase-8, epidermal growth factor receptor (EGFR), and matrix metalloproteinase (MMP)-9. Shikonin inhibited proliferation and invasive ability of QBC939 cells in a dose-dependent manner; at the same time, apoptosis of cells was also observed in a concentration-dependent fashion. Moreover, Annexin V/PI assay and Transwell invasion assay results indicated that Shikonin induced apoptosis and invasion inhibitory probably due to upregulation of caspase-3 and caspase-8 expression and downregulation of MMP-9 and EGFR expression in a concentration-dependent fashion. Shikonin could enhance apoptosis and inhibit proliferation and invasion of QBC939 cells; such biological behaviors mainly occurred via upregulating the expression of caspase-3 and caspase-8 and downregulating the expression of MMP-9 and EGFR.

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Reznik, Sergey Ya, Natalia N. Karpun, Margarita Yu Dolgovskaya, Aida Kh Saulich et Dmitry L. Musolin. « Meet Me Halfway : Will Photoperiodic Responses of Interpopulation Hybrids of the Brown Marmorated Stink Bug Halyomorpha halys (Hemiptera : Heteroptera : Pentatomidae) Promote or Constrain Subsequent Invasions ? » Diversity 14, n^o 10 (18 octobre 2022) : 878. http://dx.doi.org/10.3390/d14100878.

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Biological invasions often result from multiple invasion events. In the case of several subsequent invasive episodes, ‘newcomers’ are usually poorly adapted to local environmental conditions in contrast to the representatives of the already-established invasive population of the same species. Therefore, the mode of inheritance of life-history features determining the survival and performance of interpopulation hybrids is an important component of invasiveness. We investigated the mode of inheritance of the photoperiodic response in the brown marmorated stink bug, Halyomorpha halys, by crossing between the native population of South Korea and the invasive population of the Black Sea coast of Russia. The aim of this study was to predict the overwintering potential of the progeny from possible crosses between representatives of the native and invasive populations. The pre-adult development time and the incidence of winter adult diapause in the progeny of the interpopulation crosses were close to the average of the values recorded in ‘pure’ (unmixed) crosses. Female and male genotypes were equally important in the determination of these characters. Such a mode of inheritance is most likely determined by a polygenic control and would only partially promote subsequent invasion events from the native South Asian range of H. halys into Europe.

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Al-Assaf, Amani, Maher J. Tadros, Salsabeel Al-Shishany, Stephanie Stewart, Mohammad Majdalawi, Mohammad Tabieh et Yahia A. Othman. « Economic Assessment and Community Management of Prosopis juliflora Invasion in Sweimeh Village, Jordan ». Sustainability 12, n^o 20 (10 octobre 2020) : 8327. http://dx.doi.org/10.3390/su12208327.

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Invasions by invasive alien species (IAS) are recognized as one of the largest threats to earth’s ecosystem services and represent rapidly growing economic costs as they damage local ecosystems and force surrounding communities to divert resources towards IAS management and control. The study objectives were to assess the economic impacts of a Prosopis juliflora invasion in Jordan and gauge community preferences for management plans. The study was conducted in Sweimeh, Jordan Valley using a combination of focus groups and randomized interviews with 203 local households. Direct-use values for products derived from P. juliflora and direct costs owing to P. juliflora’s presence have been calculated. A binary logistic regression model was then developed to predict the households’ preferences between two policy responses: P. juliflora management or complete eradication. The results revealed the dualistic role of P. juliflora in household livelihoods: it was widely used for firewood, fodder, and charcoal offering benefits valued at JOD 2165 per household/year (JOD 1 = USD 0.71). At the same time, the invasion reduced household welfare by taking over arable lands and injuring humans and animals. Consequently, the income lost as a result of the invasion was estimated by JOD 1410.5 per household/year. As a result, two-thirds of respondents choose the option of P.juliflora invasion management. Only respondents’ monthly income and perception of P. juliflora’s impact on the prevention of soil erosion were significant predictors of respondents’ preferences for the management plans. In conclusion, more coordinated responses between policy makers, institutions, and local communities are required to mitigate the negative impact of P. juliflora invasion.

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Burnett, Kimberly M., Brooks A. Kaiser et James A. Roumasset. « Invasive Species Control over Space and Time : Miconia calvescens on Oahu, Hawaii ». Journal of Agricultural and Applied Economics 39, s1 (octobre 2007) : 125–32. http://dx.doi.org/10.1017/s1074070800028996.

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The optimal size and location of an invasive species population depend upon spatially differentiated biological growth, economic costs, and damages. Although largely absent from most economic models, spatial considerations matter because the likelihood and magnitude of the invasion vary spatially and the threatened assets may be unevenly distributed across space. We map the current and future populations of an invasive species, Miconia calvescens, on Oahu, Hawaii, and the potential damages to water quantity, quality, and endangered-species habitat, and weigh these against treatment costs. We find that optimal densities vary from approximately 1% to 18% cover throughout the island.

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Li, Yanfei, Shujing Wang, Juhong Chen, Kun Jiang, Jiayue Zhou, Runqi Zhu, Cuiqing Gao, Wenjun Bu et Huaijun Xue. « Out of East Asia : Early Warning of the Possible Invasion of the Important Bean Pest Stalk-Eyed Seed Bug Chauliops fallax (Heteroptera : Malcidae : Chauliopinae) ». Insects 14, n^o 5 (1 mai 2023) : 433. http://dx.doi.org/10.3390/insects14050433.

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The short stay at the beginning of the invasion process is a critical time for invasive species identification and preventing invasive species from developing a wider distribution and significant economic impact. The stalk-eyed seed bug Chauliops fallax is an important agricultural pest of soybean and was first reported to occur outside East Asia. Here, we reported the native evolutionary history, recent invasion history, and potential invasion threats of C. fallax for the first time based on population genetic methods and ecological niche modelling. The results showed that four native East Asian genetic groups (EA, WE, TL, and XZ) were well supported, showing an east-west differentiation pattern consistent with the geographical characteristics of three-step landforms in China. Two main haplotypes existed: Hap1 might have experienced a rapid northwards expansion process after the LGM period, and Hap5 reflected local adaptation to the environment in southeastern China. The Kashmir sample was found to come from the recent invasion of populations in the coastal areas of southern China. Ecological niche modelling results suggested that North America has a high risk of invasion, which might pose a serious threat to local soybean production. In addition, with future global warming, the suitable habitat in Asia will move towards the higher latitude region and gradually deviate from the soybean planting area, which indicates the threat of C. fallax to soybean production in Asia will decrease in the future. The results could provide new insights into the monitoring and management of this agricultural pest in the early invasion stage.

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Lo, Chun-Min, Jun-Chih Lo, Priscila Y. Sato, Tsz-Lun Yeung, Samuel C. Mok et Kay-Pong Yip. « Monitoring of ovarian cancer cell invasion in real time with frequency-dependent impedance measurement ». American Journal of Physiology-Cell Physiology 311, n^o 6 (1 décembre 2016) : C1040—C1047. http://dx.doi.org/10.1152/ajpcell.00211.2016.

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The conventional approach to assessing cancer invasion is primarily for end-point analysis, which does not provide temporal information on the invasion process or any information on the interactions between invading cells and the underlying adherent cells. To alleviate these limitations, the present study exploited electric cell-substrate impedance sensing (ECIS) to monitor the invasion of ovarian cancer cells (SKOV-3) through an adherent monolayer of human umbilical vein endothelial cells (HUVECs). Impedance was measured at 4 kHz of AC voltage or was measured as a function of AC frequency (25 Hz to 60 kHz). By measuring impedance at 4-kHz AC, we found that the invasion of SKOV-3 cells through the HUVEC monolayer was manifested as a rapid decrease in transendothelial electrical resistance in real time. The invasion was augmented in the presence of hepatocyte growth factor (HGF). The enhancing effect of HGF was attenuated by c-Met inhibitor (SU11274). By measuring the frequency-dependent impedance of SKOV-3 cells over time, we found that HGF-enhanced SKOV-3 cell invasion was accomplished with reduced junctional resistance ( Rb), increased average cell-substrate separation ( h), and increased micromotion. SU11274 attenuated the effects of HGF on Rb, h, and micromotion in the SKOV-3 monolayer. SU11274 also increased the barrier function of the HUVEC monolayer by increasing Rb and decreasing h. In conclusion, this study demonstrated an improved method for monitoring and studying the interactions between cancer cells and the underlying adherent cells during invasion in real time. Alterations in cellular biophysical properties ( Rb, h) associated with cancer transendothelial invasion were detected.

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