Outbreak of an undetected invasive species triggered by a climate anomaly

© The Author(s), 2016. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Ecosphere 7 (2016): e01628, doi:10.1002/ecs2.1628.When an invasive species appears at a new location, we typically have no knowledge of the population dynamics leading up to that moment. Is the establishment of invasive propagules closely followed by the appearance of the population? Or alternatively, was there an established low-density population that was released from a constraint and crossed the detection threshold? The early stages of the invasion process are a critical gap in our knowledge, yet vitally important for the detection and management of invasions. Here, we present multiple lines of evidence supporting the lag scenario for an invasive species outbreak. The invasive predatory zooplankton, spiny water flea (Bythotrephes longimanus), was detected in Lake Mendota, Wisconsin (USA), in summer of 2009 and rapidly reached and sustained exceptionally high densities. To evaluate whether Bythotrephes' outbreak immediately followed introduction or erupted from an established low-density population, we constructed a population model of Bythotrephes in Lake Mendota. In the model, Bythotrephes persisted indefinitely at low levels until favorable thermal conditions in 2009, the coolest July since at least 1895, allowed it to erupt to high densities and establish a large egg bank in the lake sediments. The egg bank stabilized the population in the high-density state despite a return to nonfavorable thermal conditions, which is further supported by demographic data suggesting a constant contribution from the egg bank during the year. The prolonged lag scenario is corroborated by the detection of two individual Bythotrephes in pre-2009 archived samples, and the detection of Bythotrephes spines in lake sediment core layers dating back to 1994 (±5 yr). Together, our results suggest that Bythotrephes persisted for at least a decade below the detection limit, until optimal thermal conditions triggered a population outbreak. This work highlights the potential for environmental conditions to trigger invasive species outbreaks from low-density populations.NSF North Temperate Lakes Long-Term Ecological Research Program Grant Numbers: DEB-0217533, DEB-1440297; Wisconsin Department of Natural Resource

Navigating discourses in place in the world of Webkinz

This is the postprint, author's accepted manuscript version of this article after peer review.Geosemiotics (Scollon and Scollon, 2003) frames this analysis of play, multimodal collaboration, and peer mediation as players navigate barriers to online connectivity in a children’s social network and gaming site. A geosemiotic perspective enables examination of children’s web play as discourses in place: fluidly converging and diverging interactions among four factors: (1) social actors, (2) interaction order, (3) visual semiotics, and (4) place semiotics. The video data are excerpted from an ethnographic study of a computer club for primary school-aged children in an afterschool program serving working-class and middle-class families in a US Midwest university community. Discourses of schooling in the computer room and Webkinz complicated children’s goal of coordinated game play and mutual participation in online games. Barriers to online connection produced ruptures that foregrounded childrens’ collaborative management of time and space. This foregrounding makes typically backgrounded practices, modes, and discourses visible and available for deconstruction and critique

Напрями та шляхи вдосконалення матеріально-технічного забезпечення підприємств АПК регіону

Background The growing number of web-based psychological treatments, based on textual communication, generates a wealth of data that can contribute to knowledge of online and face-to-face treatments. We investigated whether clients language use predicted treatment outcomes and adherence in Master Your Mood (MYM), an online group course for young adults with depressive symptoms. Methods Among 234 participants from a randomised controlled trial of MYM, we tested whether their word use on course application forms predicted baseline levels of depression, anxiety and mastery, or subsequent treatment adherence. We then analysed chat session transcripts of course completers (n=67) to investigate whether word use changes predicted changes in treatment outcomes. Results Depression improvement was predicted by increasing use of 'discrepancy words' during treatment (e.g. should). At baseline, more discrepancy words predicted higher mastery level. Adherence was predicted by more words used at application, more social words and fewer discrepancy words. Limitations Many variables were included, increasing the chance of coincidental results. This risk was constrained by examining only those word categories that have been investigated in relation to depression or adherence. Conclusions This is the first study to link word use during treatment to outcomes of treatment that has proven to be effective in an RCT. The results suggest that paying attention to the length of problem articulation at application and to 'discrepancy words' may be wise, as these seem to be psychological markers. To expand knowledge of word use as psychological marker, research on web-based treatment should include text analysis. © 2014 The Authors

Political Regimes and Sovereign Credit Risk in Europe, 1750-1913

This article uses a new panel data set to perform a statistical analysis of political regimes and sovereign credit risk in Europe from 1750 to 1913. Old Regime polities typically suffered from fiscal fragmentation and absolutist rule. By the start of World War I, however, many such countries had centralized institutions and limited government. Panel regressions indicate that centralized and?or limited regimes were associated with significant improvements in credit risk relative to fragmented and absolutist ones. Structural break tests also reveal close relationships between major turning points in yield series and political transformations

A Laboratory Study of the Effects of Size, Density, and Shape on the Wave‐Induced Transport of Floating Marine Litter

Floating marine litter is transported by several mechanisms, including surface waves. In studies of marine litter transport, the wave‐induced drift is set to be equal to the Stokes drift, corresponding to the Lagrangian‐mean wave‐induced drift of an infinitesimally small tracer. Large‐scale experiments are used to show how the wave‐induced drift of objects of finite size depends on their size, density, and shape. We observe increases in drift of 95% compared to Stokes drift for discs with diameters of 13% of the wavelength, up to 23% for spheres with diameters of 3% of the wavelength, whereas drift is reduced for objects that become submerged such as nets. We investigate what these findings may imply for the transport of plastic pollution in realistic wave conditions and we predict an increase in wave‐induced drift for (very) large plastic pollution objects. The different extrapolation techniques we explore to make this prediction exhibit a large range of uncertainty

Online cognitive-based intervention for depression: exploring possible circularity in mechanisms of change.

Background. This study investigates possible circularity in mechanisms of change in participants of Master Your Mood (MYM), a cognitive-based, online intervention for young adults with depressive symptoms. A previous study showed that MYM effectively reduced depression and anxiety and strengthened mastery

Blocking Complement Factor B Activation Reduces Renal Injury and Inflammation in a Rat Brain Death Model

Introduction: The majority of kidneys used for transplantation are retrieved from brain-dead organ donors. In brain death, the irreversible loss of brain functions results in hemodynamic instability, hormonal changes and immunological activation. Recently, brain death has been shown to cause activation of the complement system, which is adversely associated with renal allograft outcome in recipients. Modulation of the complement system in the brain-dead donor might be a promising strategy to improve organ quality before transplantation. This study investigated the effect of an inhibitory antibody against complement factor B on brain death-induced renal inflammation and injury. Method: Brain death was induced in male Fischer rats by inflating a balloon catheter in the epidural space. Anti-factor B (anti-FB) or saline was administered intravenously 20 min before the induction of brain death (n = 8/group). Sham-operated rats served as controls (n = 4). After 4 h of brain death, renal function, renal injury, and inflammation were assessed. Results: Pretreatment with anti-FB resulted in significantly less systemic and local complement activation than in saline-treated rats after brain death. Moreover, anti-FB treatment preserved renal function, reflected by significantly reduced serum creatinine levels compared to saline-treated rats after 4 h of brain death. Furthermore, anti-FB significantly attenuated histological injury, as seen by reduced tubular injury scores, lower renal gene expression levels (>75%) and renal deposition of kidney injury marker-1. In addition, anti-FB treatment significantly prevented renal macrophage influx and reduced systemic IL-6 levels compared to saline-treated rats after brain death. Lastly, renal gene expression of IL-6, MCP-1, and VCAM-1 were significantly reduced in rats treated with anti-FB. Conclusion: This study shows that donor pretreatment with anti-FB preserved renal function, reduced renal damage and inflammation prior to transplantation. Therefore, inhibition of factor B in organ donors might be a promising strategy to reduce brain death-induced renal injury and inflammation.Nephrolog