How weeds emerge: a taxonomic and trait‐based examination using United States data

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106812/1/nph12698.pd

Duox, Flotillin-2, and Src42A Are Required to Activate or Delimit the Spread of the Transcriptional Response to Epidermal Wounds in Drosophila

The epidermis is the largest organ of the body for most animals, and the first line of defense against invading pathogens. A breach in the epidermal cell layer triggers a variety of localized responses that in favorable circumstances result in the repair of the wound. Many cellular and genetic responses must be limited to epidermal cells that are close to wounds, but how this is regulated is still poorly understood. The order and hierarchy of epidermal wound signaling factors are also still obscure. The Drosophila embryonic epidermis provides an excellent system to study genes that regulate wound healing processes. We have developed a variety of fluorescent reporters that provide a visible readout of wound-dependent transcriptional activation near epidermal wound sites. A large screen for mutants that alter the activity of these wound reporters has identified seven new genes required to activate or delimit wound-induced transcriptional responses to a narrow zone of cells surrounding wound sites. Among the genes required to delimit the spread of wound responses are Drosophila Flotillin-2 and Src42A, both of which are transcriptionally activated around wound sites. Flotillin-2 and constitutively active Src42A are also sufficient, when overexpressed at high levels, to inhibit wound-induced transcription in epidermal cells. One gene required to activate epidermal wound reporters encodes Dual oxidase, an enzyme that produces hydrogen peroxide. We also find that four biochemical treatments (a serine protease, a Src kinase inhibitor, methyl-ß-cyclodextrin, and hydrogen peroxide) are sufficient to globally activate epidermal wound response genes in Drosophila embryos. We explore the epistatic relationships among the factors that induce or delimit the spread of epidermal wound signals. Our results define new genetic functions that interact to instruct only a limited number of cells around puncture wounds to mount a transcriptional response, mediating local repair and regeneration

Neuronal Control of Metabolism through Nutrient-Dependent Modulation of Tracheal Branching

SummaryDuring adaptive angiogenesis, a key process in the etiology and treatment of cancer and obesity, the vasculature changes to meet the metabolic needs of its target tissues. Although the cues governing vascular remodeling are not fully understood, target-derived signals are generally believed to underlie this process. Here, we identify an alternative mechanism by characterizing the previously unrecognized nutrient-dependent plasticity of the Drosophila tracheal system: a network of oxygen-delivering tubules developmentally akin to mammalian blood vessels. We find that this plasticity, particularly prominent in the intestine, drives—rather than responds to—metabolic change. Mechanistically, it is regulated by distinct populations of nutrient- and oxygen-responsive neurons that, through delivery of both local and systemic insulin- and VIP-like neuropeptides, sculpt the growth of specific tracheal subsets. Thus, we describe a novel mechanism by which nutritional cues modulate neuronal activity to give rise to organ-specific, long-lasting changes in vascular architecture

A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)

Meeting abstrac

The response of plant community diversity to alien invasion: evidence from a sand dune time series

This study examines the process of invasion of coastal dunes in north-eastern Italy along a 60-year time series considering alien attributes (origin, residence time, invasive status, and growth form strategy) and habitat properties (species richness, diversity and evenness, proportion of aliens, and proportion of focal species). Vegetation changes through time were investigated in four sandy coastal habitats, using a fine-scale diachronic approach that compared vegetation data collected by use of the same procedure, in four time periods, from the 1950s to 2011. Our analysis revealed an overall significant decline of species richness over the last six decades. Further, both the average number of species per plot and the mean focal species proportion were proved to be negatively affected by the increasing proportion of alien species at plot level. The severity of the impact, however, was found to be determined by a combination of species attributes, habitat properties, and human disturbance suggesting that alien species should be referred to as ‘‘passengers’’ and not as ‘‘drivers’’ of ecosystem change. Passenger alien species are those which take advantage of disturbances or other changes to which they are adapted but that lead to a decline in native biodiversity. Their spread is facilitated by widespread anthropogenic environmental alterations, which create new, suitable habitats, and ensure human-assisted dispersal, reducing the distinctiveness of plant communities and inducing a process of biotic homogenization

Crystallinity of silicon nanoparticles: Direct influence on the electrochemical performance of lithium ion battery anodes

The use of silicon (Si) in the form of nanoparticles is one of the most promising routes for boosting the capacity of modern Li‐ion batteries. Many parameters influence the performance of Si making the comparison of materials complicated. The present work demonstrates a direct comparison of Si nanoparticles with amorphous and crystalline structures prepared through the same chemistry with the same particle size and morphology. The amorphous Si nanoparticles with an average diameter of 100 nm were synthesized through silane pyrolysis, and their crystalline analogues were obtained through subsequent annealing not altering size or morphology of the nanoparticles. Such direct comparison allows evaluation of the specific impact of crystallinity on the material's performance. From electrochemical analysis of these materials, the electrodes prepared from amorphous nanoparticles were found to exhibit improved cycle life compared to electrodes prepared from crystalline nanoparticles when the delithiation capacity of the anode was limited to 1000 mAh/gSi.publishedVersio

Crystallinity of silicon nanoparticles: Direct influence on the electrochemical performance of lithium ion battery anodes

The use of silicon (Si) in the form of nanoparticles is one of the most promising routes for boosting the capacity of modern Li‐ion batteries. Many parameters influence the performance of Si making the comparison of materials complicated. The present work demonstrates a direct comparison of Si nanoparticles with amorphous and crystalline structures prepared through the same chemistry with the same particle size and morphology. The amorphous Si nanoparticles with an average diameter of 100 nm were synthesized through silane pyrolysis, and their crystalline analogues were obtained through subsequent annealing not altering size or morphology of the nanoparticles. Such direct comparison allows evaluation of the specific impact of crystallinity on the material's performance. From electrochemical analysis of these materials, the electrodes prepared from amorphous nanoparticles were found to exhibit improved cycle life compared to electrodes prepared from crystalline nanoparticles when the delithiation capacity of the anode was limited to 1000 mAh/gSi

Crystallinity of silicon nanoparticles: Direct influence on the electrochemical performance of lithium ion battery anodes

The use of silicon (Si) in the form of nanoparticles is one of the most promising routes for boosting the capacity of modern Li‐ion batteries. Many parameters influence the performance of Si making the comparison of materials complicated. The present work demonstrates a direct comparison of Si nanoparticles with amorphous and crystalline structures prepared through the same chemistry with the same particle size and morphology. The amorphous Si nanoparticles with an average diameter of 100 nm were synthesized through silane pyrolysis, and their crystalline analogues were obtained through subsequent annealing not altering size or morphology of the nanoparticles. Such direct comparison allows evaluation of the specific impact of crystallinity on the material's performance. From electrochemical analysis of these materials, the electrodes prepared from amorphous nanoparticles were found to exhibit improved cycle life compared to electrodes prepared from crystalline nanoparticles when the delithiation capacity of the anode was limited to 1000 mAh/gSi