12 research outputs found

    Host specificity and risk assessment of Archanara geminipuncta and Archanara neurica, two potential biocontrol agents for invasive Phragmites australis in North America

    Get PDF
    Invasive Phragmites australis is widespread in North America and despite decades of management and large annual expenditures (\u3e5 million US$) using physical and chemical means, local populations and the species range are expanding. Allowing continued expansion does not only threaten native wetland biota but also an endemic North American subspecies Phragmites australis americanus. We used extensive multi-pronged investigations in Europe and North America to evaluate host specificity and impact of two European stem mining noctuid moths, Archanara geminipuncta and A. neurica. Both moth species are specific to the genus Phragmites and both show a very strong, but not absolute, preference for invasive P. australis over endemic P. australis americanus. No-choice tests or tests in small cages provided inconsistent results, but both moths showed consistently high preferences for introduced P. australis. Open field multiple-choice oviposition tests affirmed this; moths laid 6.5% of their eggs on native P. australis americanus. The native subspecies is further safeguarded by increased mortality of eggs and larvae when laid on, or developing in P. australis americanus. Phragmites populations in the southern US, particularly along the Gulf of Mexico, occur outside the climate range of these two temperate moth species. We consider potential threats to P. australis americanus demography due to A. geminipuncta and A. neurica attack to be far smaller than allowing expansion of invasive P. australis to continue. We therefore recommend release of these two biocontrol agents in North America

    When misconceptions impede best practices: evidence supports biological control of invasive Phragmites

    Get PDF
    Development of a biological control program for invasive Phagmites australis australis in North America required 20 years of careful research, and consideration of management alternatives. A recent paper by Kiviat et al. (Biol Invasions 21:2529–2541, 2019. https://doi.org/10.1007/s10530-019-02014-9) articulates opposition to this biocontrol program and questions the ethics and thoroughness of the researchers. Here we address inaccuracies and misleading statements presented in Kiviat et al. (2019), followed by a brief overview of why biological control targeting Phragmites in North America can be implemented safely with little risk to native species. Similar to our colleagues, we are very concerned about the risks invasive Phragmites represent to North American habitats. But to protect those habitats and the species, including P. australis americanus, we come to a different decision regarding biological control. Current management techniques have not been able to reverse the invasiveness of P. australis australis, threats to native rare and endangered species continue, and large-scale herbicide campaigns are not only costly, but also represent threats to non-target species. We see implementation of biocontrol as the best hope for managing one of the most problematic invasive plants in North America. After extensive review, our petition to release two host specific stem miners was approved by The Technical Advisory Group for the Release of Biological Control Agents in the US and Canadian federal authorities

    Spermidine ameliorates colitis via induction of anti-inflammatory macrophages and prevention of intestinal dysbiosis

    Get PDF
    BACKGROUND AND AIMS: Exacerbated immune activation, intestinal dysbiosis, and a disrupted intestinal barrier are common features among inflammatory bowel disease (IBD) patients. The polyamine spermidine, which is naturally present in all living organisms, is an integral component of the human diet, and exerts beneficial effects in human diseases. Here, we investigated whether spermidine treatment ameliorates intestinal inflammation and offers therapeutic potential for IBD treatment. METHODS: We assessed the effect of oral spermidine administration on colitis severity in the T cell transfer colitis model in Rag2 -/- mice by analysis of endoscopy, histology, and molecular inflammation markers. The effects on the intestinal microbiome were determined by 16S sequencing of mouse feces. The impact on intestinal barrier integrity was evaluated in co-cultures of patient-derived macrophages with intestinal epithelial cells. RESULTS: Spermidine administration protected mice from intestinal inflammation in a dose-dependent manner. While T helper cell subsets remained unaffected, spermidine promoted anti-inflammatory macrophages and prevented the microbiome shift from Firmicutes and Bacteroides to Proteobacteria, maintaining a healthy gut microbiome. Consistent with spermidine as a potent activator of the anti-inflammatory molecule protein tyrosine phosphatase non-receptor type 2 (PTPN2), its colitis-protective effect was dependent on PTPN2 in intestinal epithelial cells and in myeloid cells. The loss of PTPN2 in epithelial and myeloid cells, but not in T cells, abrogated the barrier-protective, anti-inflammatory effect of spermidine and prevented the anti-inflammatory polarization of macrophages. CONCLUSION: Spermidine reduces intestinal inflammation by promoting anti-inflammatory macrophages, maintaining a healthy microbiome, and preserving epithelial barrier integrity in a PTPN2-dependent manner

    Das Gedenken an die Schlacht von Murten von 1476

    No full text

    Complete host specificity test plant list and associated data to assess host specificity of Archanara geminipuncta and Archanara neurica, two potential biocontrol agents for invasive Phragmites australis in North America

    Get PDF
    Introduced European genotypes of Phragmites australis are invasive and widespread in North America. Decades of management using herbicide and other means have failed to control the species and its range and populations continue to expand. Allowing continued invasion threatens native wetland biota and an endemic North American subspecies Phragmites australis americanus. The lack of conventional management to control introduced P. australis triggered research to assess host specificity of two European noctuid moths, Archanara geminipuncta and Archanara neurica. These two species are considered particularly promising potential biocontrol agents for introduced P. australis. Here we provide the complete and approved list of test plants used to assess host specificity of A. geminipuncta and A. neurica. This includes data on neonate larval acceptance and survival under no-choice conditions, and oviposition tests for all plant species tested, including for different Phragmites subspecies currently occurring in North America. We further provide temperature profiles of select cities in the temperate native European distribution of the two noctuids and those in southern US climates. We used these long-term temperature records to assess whether overwintering eggs of A. geminipuncta and A. neurica can survive under climate conditions typical for the Gulf Coast region in North America. This data article refers to “Host specificity and risk assessment of Archanara geminipuncta and Archanara neurica, two potential biocontrol agents for invasive Phragmites australis in North America Biol. Control (2018)”. Keywords: Archanara, Biological weed control, Host specificity, Phragmites, Sub-species level specificity, Wetland

    Potential for biological control of Phragmites australis in North America

    No full text
    Phragmites australis is a cosmopolitan plant that is undergoing a population explosion in freshwater and tidal wetlands on the east coast of North America. The rapid spread of P. australis in recent years and the virtual absence of native herbivores feeding on P. australis have led wetland ecologists to believe that either the species or more aggressive genotypes were introduced. The historical record of the occurrence of P. australis in North America and the scarcity of indigenous herbivores provide conflicting evidence for the status of the species as native or introduced. A comparison of P. australis populations from North America and other continents using advanced genetic techniques is underway to help determine the status of current and historic North American genotypes. Literature and field surveys reveal that of the 26 herbivores currently known to feed on P. australis in North America (many accidentally introduced during the last decade), only 5 are native. In Europe, over 170 herbivore species have been reported feeding on P. australis, some causing significant damage. Of these herbivores, rhizome-feeding species with considerable negative impact on P. australis performance include the lepidopterans Rhizedra lutosa (already present in North America), Phragmataecia castaneae, Chilo phragmitella, and Schoenobius gigantella. Stemboring moths in the genera Archanara and Arenostola and the chloropid fly Platycephala planifrons can have large detrimental impacts on P. australis in Europe and should be evaluated for their potential as biological control agents. In addition, the interaction of potential control agents with accidentally introduced P. australis herbivores needs to be evaluated in North America. Regardless of the results of the genetic analyses, any decision to introduce additional host-specific herbivores in an attempt to control P. australis will require considerable dialogue. This decision needs to weigh the current negative ecological and economic impacts of P. australis and the benefits and risks of a biological control program. © 2001 Elsevier Science

    Grasses as appropriate targets in weed biocontrol: is the common reed, Phragmites australis, an anomaly?

    No full text
    Despite their importance as invasive species, there has been a hesitation to target grasses in classical biocontrol. This historic bias appears to be changing with multiple active research and release programs. Similarly, biocontrol workers appear to avoid targeting species with native congeners. These biases appear inappropriate as the ecological and entomological literature provide abundant evidence for sub-genus specificity for many herbivores, including those attacking grasses. The biocontrol program targeting Phragmites australis (Cav.) Trin. ex Steud (Poaceae) provides an informative example with endemic subspecies in North America and many sub-genus specific herbivores, including potential European control agents. Grasses and target weeds with congeneric native species require rigorous host range testing, similar to all other targets in current weed biological control programs. Furthermore, it appears prudent to ask petition reviewers and regulatory agencies to abandon their focus on results of no-choice studies and to distinguish between trivial feeding and demographic impacts

    Total water storage variability from GRACE mission and hydrological models for a 50,000 km2 temperate watershed: the Garonne River basin (France)

    No full text
    International audienceStudy Region Garonne Basin, France. Study Focus This study analyses water mass variations for the whole Garonne basin (50,000 km2 drainage area). To do so, Total Water Storage Anomalies (TWSA) from seven global solutions based on the Gravity Recovery And Climate Experiment (GRACE) satellite mission measurements (˜300 km spatial resolution) are inter-compared with TWSA from two hydrological models, SAFRAN-ISBA-MODCOU (SIM) and Soil and Water Assessment Tool (SWAT), between January 2003 and December 2010. New Hydrological Insights for the Region Despite the small size of the Garonne basin compared to GRACE spatial resolution, good agreement between GRACE solutions and hydrological model TWSA has been found (maximum correlation coefficient ˜0.9 and Nash-Sutcliffe Efficiency, NSE, ˜0.7). These datasets showed that TWSA in the Garonne basin is mainly due to water stored in the first dozen meters of soil and in the shallow aquifer. To a smaller extent, snow also influences Garonne TWSA. Open surface water TWSA is quite small and TWSA from deep aquifer is negligible. The most important drought period occurred in 2011/2012, due to low precipitation during the two hydrological years and ETR close to previous years. Important precipitation in 2013/2014 helps to refill the water stocks. This study also showed that GRACE and models mismatches should be due to GRACE poor spatial resolution, but also to its monthly time resolution (rarely shown in previous studies)

    Toward real-time particle tracking using an event-based dynamic vision sensor

    Full text link
    Optically based measurements in high Reynolds number fluid flows often require high-speed imaging techniques. These cameras typically record data internally and thus are limited by the amount of onboard memory available. A novel camera technology for use in particle tracking velocimetry is presented in this paper. This technology consists of a dynamic vision sensor in which pixels operate in parallel, transmitting asynchronous events only when relative changes in intensity of approximately 10% are encountered with a temporal resolution of 1 mu s. This results in a recording system whose data storage and bandwidth requirements are about 100 times smaller than a typical high-speed image sensor. Post-processing times of data collected from this sensor also increase to about 10 times faster than real time. We present a proof-of-concept study comparing this novel sensor with a high-speed CMOS camera capable of recording up to 2,000 fps at 1,024 x 1,024 pixels. Comparisons are made in the ability of each system to track dense (rho >1 g/cm(3)) particles in a solid-liquid two-phase pipe flow. Reynolds numbers based on the bulk velocity and pipe diameter up to 100,000 are investigated

    The FAK inhibitor BI 853520 exerts anti-tumor effects in breast cancer.

    Get PDF
    Focal adhesion kinase (FAK) is a cytoplasmic tyrosine kinase that regulates a plethora of downstream signaling pathways essential for cell migration, proliferation and death, processes that are exploited by cancer cells during malignant progression. These well-established tumorigenic activities, together with its high expression and activity in different cancer types, highlight FAK as an attractive target for cancer therapy. We have assessed and characterized the therapeutic potential and the biological effects of BI 853520, a novel small chemical inhibitor of FAK, in several preclinical mouse models of breast cancer. Treatment with BI 853520 elicits a significant reduction in primary tumor growth caused by an anti-proliferative activity by BI 853520. In contrast, BI 853520 exerts effects with varying degrees of robustness on the different stages of the metastatic cascade. Together, the data demonstrate that the repression of FAK activity by the specific FAK inhibitor BI 853520 offers a promising anti-proliferative approach for cancer therapy
    corecore