Phenotypic Plasticity and the Invasiveness of Three _Taraxacum_ Species

*Background/Question/Methods* 
Many factors have been found to be associated with the success of invasive species. Phenotypic plasticity, the ability of a plant genotype to respond to different environmental conditions by producing different phenotypes, is thought to play an important role plant invasions. In three major experiments, I tested the hypothesis that the invasive _Taraxacum officinale_ (common dandelion) and its non-invasive congener _T. laevigatum_ will exhibit different phenotypic plasticity in germination, growth, and reproduction. I also proposed that their responses to various environments could be used to assess the invasive behavior of a potential crop species: _T. kok-saghyz_.

*Results/Conclusions* 
The results revealed complicated responses of the three species in various environments. The invasive _T. officinale_ showed higher germination in high alternating temperature, and accumulated more biomass than the non-invasive _T. laevigatum_ in favorable greenhouse conditions. Surprisingly, _T. laevigatum_ germinated better than _T. officinale_ in other stressful environments (dark, low water potential, long aging period), and also exhibited higher fecundity in favorable greenhouse conditions. In field experiments, however, the performance of _T. officinale_ was overwhelmingly better than _T. laevigatum_, which suffered very high mortality and failed to survive for more than two growing seasons. These results suggest that _T. officinale_ might benefit from its ability to grow, reproduce, and survive in various environments, while _T. laevigatum_ relies on seed reproduction to maintain its population. With the exception of germination, the responses of _T. kok-saghyz_ were more like _T. officinale_ than _T. laevigatum_, which suggested that this species has some potential to behave as a weed

Cerebellum: an explanation for dystonia?

Dystonia is a movement disorder that is characterized by involuntary muscle contractions, abnormal movements and postures, as well as by non-motor symptoms, and is due to abnormalities in different brain areas. In this article, we focus on the growing number of experimental studies aimed at explaining the pathophysiological role of the cerebellum in dystonia. Lastly, we highlight gaps in current knowledge and issues that future research studies should focus on as well as some of the potential applications of this research avenue. Clarifying the pathophysiological role of cerebellum in dystonia is an important concern given the increasing availability of invasive and non-invasive stimulation techniques and their potential therapeutic role in this condition

Goal-directed therapy in intraoperative fluid and hemodynamic management.

Intraoperative fluid management is pivotal to the outcome and success of surgery, especially in high-risk procedures. Empirical formula and invasive static monitoring have been traditionally used to guide intraoperative fluid management and assess volume status. With the awareness of the potential complications of invasive procedures and the poor reliability of these methods as indicators of volume status, we present a case scenario of a patient who underwent major abdominal surgery as an example to discuss how the use of minimally invasive dynamic monitoring may guide intraoperative fluid therapy

Surveying the Potential Range Extension of Invasive Mystery Snails within Central Virginia

Undergraduat

Incorporating climate change into invasive species management: insights from managers

Invasive alien species are likely to interact with climate change, thus necessitating management that proactively addresses both global changes. However, invasive species managers’ concerns about the effects of climate change, the degree to which they incorporate climate change into their management, and what stops them from doing so remain unknown. Therefore, we surveyed natural resource managers addressing invasive species across the U.S. about their priorities, concerns, and management strategies in a changing climate. Of the 211 managers we surveyed, most were very concerned about the influence of climate change on invasive species management, but their organizations were significantly less so. Managers reported that lack of funding and personnel limited their ability to effectively manage invasive species, while lack of information limited their consideration of climate change in decision-making. Additionally, managers prioritized research that identifies range-shifting invasive species and native communities resilient to invasions and climate change. Managers also reported that this information would be most effectively communicated through conversations, research summaries, and meetings/symposia. Despite the need for more information, 65% of managers incorporate climate change into their invasive species management through strategic planning, preventative management, changing treatment and control, and increasing education and outreach. These results show the potential for incorporating climate change into management, but also highlight a clear and pressing need for more targeted research, accessible science communication, and two-way dialogue between researchers and managers focused on invasive species and climate change.https://link.springer.com/content/pdf/10.1007/s10530-019-02087-6.pdfPublished versio

Combining local- and large-scale models to predict the distributions of invasive plant species

Habitat-distribution models are increasingly used to predict the potential distributions of invasive species and to inform monitoring. However, these models assume that species are in equilibrium with the environment, which is clearly not true for most invasive species. Although this assumption is frequently acknowledged, solutions have not been adequately addressed. There are several potential methods for improving habitat-distribution models. Models that require only presence data may be more effective for invasive species, but this assumption has rarely been tested. In addition, combining modeling types to form ‘ensemble’ models may improve the accuracy of predictions. However, even with these improvements, models developed for recently invaded areas are greatly influenced by the current distributions of species and thus reflect near- rather than long-term potential for invasion. Larger scale models from species’ native and invaded ranges may better reflect long-term invasion potential, but they lack finer scale resolution. We compared logistic regression (which uses presence/absence data) and two presence-only methods for modeling the potential distributions of three invasive plant species on the Olympic Peninsula in Washington State, USA. We then combined the three methods to create ensemble models. We also developed climate-envelope models for the same species based on larger scale distributions and combined models from multiple scales to create an index of near- and long-term invasion risk to inform monitoring in Olympic National Park (ONP). Neither presence-only nor ensemble models were more accurate than logistic regression for any of the species. Larger scale models predicted much greater areas at risk of invasion. Our index of near- and long-term invasion risk indicates that \u3c4% of ONP is at high near-term risk of invasion while 67-99% of the Park is at moderate or high long-term risk of invasion. We demonstrate how modeling results can be used to guide the design of monitoring protocols and monitoring results can in turn be used to refine models. We propose that by using models from multiple scales to predict invasion risk and by explicitly linking model development to monitoring, it may be possible to overcome some of the limitations of habitat-distribution models

Potential applications of randomised graph sampling to invasive species surveillance and monitoring.

Abstract Many invasive plants and animals disperse preferentially through linear networks in the landscape, including road networks, riparian corridors, and power transmission lines. Unless the network of interest is small, or the budget for surveillance is large, it may be necessary to draw inferences from a sample rather than a complete census on the network. Desired features of a surveillance system to detect and quantify invasion include: (1) the ability to make unbiased statements about the spatial extent of invasion, the abundance of the invading organism, and the degree of impact; (2) the ability to quantify the uncertainty associated with those statements; (3) the ability to sample by moving within the network in a reasonable fashion, and with little wasted non-measurement time; and (4) the ability to incorporate auxiliary information (such as remotely sensed data, ecological models, or expert opinion) to direct sampling where it will be most fruitful. Randomised graph sampling (RGS) has all of these attributes. The network of interest (such as a road network) is recomposed into a graph, consisting of vertices (such as road intersections) and edges (such as road segments connecting nodes). The vertices and edges are used to construct paths representing reasonable sampling routes through the network; these paths are then sampled, potentially with unequal probability. Randomised graph sampling is unbiased, and the incorporation of auxiliary information can dramatically reduce sample variances. We illustrate RGS using simplified examples, and a survey of Polygonum cuspidatum (Siebold & Zucc.) within a high-priority conservation region in southern Maine, USA

Managing Invasive Species: How Much Do We Spend?

Invasive species: they’re along roadways and up mountain trails; they’re in lakes and along the coast; chances are they’re in your yard. You might not recognize them for what they are—plants or animals not native to Alaska, brought here accidentally or intentionally, crowding out local species. This problem is in the early stages here, compared with what has happened in other parts of the country. But a number of invasive species are already here, and scientists think more are on the way. These species can damage ecosystems and economies—so it’s important to understand their potential economic and other effects now, when it’s more feasible to remove or contain them. Here we summarize our analysis of what public and private groups spent to manage invasive species in Alaska from 2007 through 2011. This publication is a joint product of ISER and the Alaska SeaLife Center, and it provides the first look at economic effects of invasive species here. Our findings are based on a broad survey of agencies and organizations that deal with invasive species.1 The idea for the research came out of a working group formed to help minimize the effects of invasive species in Alaska.2 Several federal and state agencies and organizations funded the work (see back page).Prince William Sound Regional Citizens Advisory Council. The United States Fish and Wildlife Service. Ocean Alaska Science and Learning Center. Alaska Legislative Council. Bureau of Land Management

THE USE OF COST-TRANSFER ANALYSIS TO ESTIMATE THE ECONOMIC IMPACTS OF A POTENTIAL ZEBRA MUSSEL INFESTATION IN FLORIDA

Zebra mussel (Dreissena polymorpha) colonization of the eastern United States has resulted in expenditures of tens of millions of dollars spent by consumptive surface water users, in order to mitigate infrastructure impairment caused by this invasive species. Analogous to benefit-transfer analysis, a "cost-transfer" approach will be used to obtain general estimates of potential mitigation costs of zebra mussels in an area (Florida) that this invasive species has yet to establish itself. The goal of this research is to provide initial information about this issue to parties interested in, and/or charged with, invasive species management in the state of Florida.Bio-fouling, cost-transfer, economic impacts, Florida surface water users, monitoring and control, zebra mussels, Risk and Uncertainty,

On the Non-invasive Measurement of the Intrinsic Quantum Hall Effect

With a model calculation, we demonstrate that a non-invasive measurement of intrinsic quantum Hall effect defined by the local chemical potential in a ballistic quantum wire can be achieved with the aid of a pair of voltage leads which are separated by potential barriers from the wire. B\"uttiker's formula is used to determine the chemical potential being measured and is shown to reduce exactly to the local chemical potential in the limit of strong potential confinement in the voltage leads. Conditions for quantisation of Hall resistance and measuring local chemical potential are given.Comment: 16 pages LaTex, 2 post-script figures available on reques