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Parasites can influence host population health and dynamics and are often an overlooked aspect of the ecology of ecosystems. Understanding the impacts of ecological interactions between parasites and small mammals can provide insights into ecosystem dynamics. We live trapped small mammals within the Apostle Islands archipelago (2017-2020) and assessed factors influencing the presence of mites from the Trombiculidae family. Archipelagos provide unique research opportunities because in small mammal-parasitic trombiculid systems, they are essentially closed systems. We detected trombiculids on 47% of red-backed vole (Myodes gapperi (Vigors, 1830)) individuals but rarely detected trombiculids on other species. We developed and ranked a set of a priori logistic regression models of trombiculid presence relative to habitat quality, host abundance, body condition, sex, and sexual maturity to identify factors significant in predicting trombiculid infection for M. gapperi. Parasitic trombiculids were more likely when M. gapperi abundance was high and body condition was poor; however, it is unknown whether trombiculids affect condition or if trombiculids are more likely to parasitize hosts in poor condition. The significance of host abundance may indicate density-dependent transmission. Our work suggests that host density and body condition are important factors influencing parasitism by trombiculids in M. gapperi populations. Key words: density dependence, host condition, Myodes gapperi, parasitism, red-backed vole, Trombiculidae Les parasites peuvent influencer la santé et la dynamique des populations de leurs hôtes et constituent souvent un aspect négligé de l'écologie des écosystèmes. La compréhension des impacts des interactions écologiques de parasites et de petits mammifères peut fournir de l'information sur la dynamique des écosystèmes. Nous avons piégé vivants de petits mammifères dans l'archipel des îles des Apôtres (2017-2020) et évalué les facteurs qui influencent la présence d'acariens de la famille des trombiculidés. Les archipels offrent des possibilités de recherche uniques parce que, pour des systèmes à petits mammifères-trombiculidés parasites, ils constituent essentiellement des systèmes fermés. Nous avons décelé des trombiculidés sur 47 % des campagnols à dos roux de Gapper (Myodes gapperi (Vigors, 1830)), mais rarement sur d'autres espèces. Nous avons élaboré et ordonné un ensemble de modèles de régression logistique a priori de la présence de trombiculidés en fonction de la qualité de l'habitat et de l'abondance, de l'embonpoint, du sexe et de la maturité sexuelle des hôtes afin de cerner les facteurs significatifs pour la prédiction d'infections aux trombiculidés de M. gapperi. Si la présence de trombiculidés parasites était plus probable quand l'abondance des campagnols était élevée et que leur embonpoint était faible, il n'est pas possible de dire si les trombiculidés ont une incidence sur l'embonpoint ou s'ils sont plus susceptibles de parasiter des hôtes de faible embonpoint. La significativité de l'abondance des hôtes pourrait refléter une transmission dépendante de la densité. Nos travaux donnent à penser que la densité et l'embonpoint des hôtes sont des facteurs importants qui influencent le parasitisme de trombiculidés dans les populations de M. gapperi. [Traduit par la Rédaction] Mots-clés : dépendance sur la densité, embonpoint de l'hôte, Myodes gapperi, parasitisme, campagnol à dos roux, trombiculidés, Introduction Parasites can influence the structure and function of ecosystems. Host manipulation by parasites can cause phe-notypic alterations that modify competition processes, food web structure and energy flow, as well [...]

Simple Summary: How people feel about large carnivores can be critical in determining the success of conservation efforts. In some cases, people's attitudes towards large carnivores are more influenced by policies dictating how people can interact with those species rather than the species themselves. Yet, the connections between policy and tolerance of large carnivores remain unclear. To better understand these connections, we surveyed residents of northern Wisconsin, USA, about wolves Canis lupus and wolf policies. We grouped survey respondents based on their general attitudes towards wolves and assessed whether respondents expected their tolerance of wolves to improve under different policy scenarios. Hunters, people with generally negative or ambivalent attitudes towards wolves, and people with wildlife conflict experience were more likely to expect their tolerance to improve under policy scenarios that allowed for the regulated killing of wolves under certain circumstances. However, we also observed important nuances in the relationship between tolerance of wolves and wolf policy. Large carnivore conservationists must balance conservation objectives with the preferences of local people. The fulcrum of this balance may shift over time as local preferences or species status change. Thus, monitoring local policy preferences may be just as important as carnivore population monitoring. Success in large carnivore conservation often hinges on local residents' tolerance towards those species. Feelings of powerlessness and frustration with wildlife policies can lead to intolerance of the species. In extreme cases, intolerance may manifest in poaching. Thus, changes in policy may influence the tolerance of wildlife. To examine the connections between policy and tolerance, we examined how policy scenarios influenced anticipated changes in tolerance to wolves Canis lupus. We administered a survey in 2015–2016 in the core wolf range within northern Wisconsin, USA. Using hierarchical cluster analysis, we clustered respondents into groups based on their current tolerance of wolves. We evaluated the behavioral intentions of the clusters and examined the influence of policy scenarios on respondents' anticipated changes in tolerance. Finally, using an information-theoretic model selection framework, we assessed the effects of tolerance clusters and demographic factors. The respondents were clustered into three clusters relative to their current tolerance towards wolves: positive, ambivalent, and negative. Each cluster exhibited significantly different behavioral intentions and anticipated changes in tolerance for all scenarios. In all scenarios, respondents who already held positive attitudes towards wolves were significantly less likely to report expected changes in tolerance toward wolves following changes in wolf management. However, respondents who held ambivalent or negative attitudes towards wolves were significantly more likely to report expected changes in tolerance towards wolves following changes in wolf management. Regarding a regulated wolf hunting and trapping season, we observed a Simpson's Paradox, wherein, when examined in aggregate, no clear pattern emerged, but when examined at the cluster level, important and intuitive patterns emerged. Our demographic model results suggest that policy changes resulting in greater state management authority over wolves, especially authority to implement certain forms of legal killing of wolves, could result in significant increases in tolerance for individuals who identify as hunters, have lost livestock to a predator, or are currently ambivalent or negative towards wolves. Our work elucidates the nuanced relationship between tolerance of wildlife and wildlife policy and identifies a potential ecological fallacy. [ABSTRACT FROM AUTHOR]

Artemis is a single-stranded endonuclease, deficiency of which results in a radiation-sensitive form of severe combined immunodeficiency (SCID-A) most effectively treated by allogeneic hematopoietic stem cell (HSC) transplantation and potentially treatable by administration of genetically corrected autologous HSCs. We previously reported cytotoxicity associated with Artemis overexpression and subsequently characterized the human Artemis promoter with the intention to provide Artemis expression that is nontoxic yet sufficient to support immunodevelopment. Here we compare the human Artemis promoter (APro) with the moderate-strength human phosphoglycerate kinase (PGK) promoter and the strong human elongation factor-1α (EF1α) promoter to regulate expression of Artemis after ex vivo lentiviral transduction of HSCs in a murine model of SCID-A. Recipient animals treated with the PGK-Artemis vector exhibited moderate repopulation of their immune compartment, yet demonstrated a defective proliferative T lymphocyte response to in vitro antigen stimulation. Animals treated with the EF1α-Artemis vector displayed high levels of T lymphocytes but an absence of B lymphocytes and deficient lymphocyte function. In contrast, ex vivo transduction with the APro-Artemis vector supported effective immune reconstitution to wild-type levels, resulting in fully functional T and B lymphocyte responses. These results demonstrate the importance of regulated Artemis expression in immune reconstitution of Artemis-deficient SCID.

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The dynamic behavior of magnetic fields surrounding adjacent current-carrying conductors is investigated for the purpose of point-field-based current sensing. The influence of eddy currents on magnetic field distribution over the useful spectrum (dc to 1 MHz) is quantified by using a spatially dependent metric, the 5% flat bandwidth (FBW). A comparison of field distributions at dc and 1 MHz shows the origin of the FBW function, which is unique to each conductor's cross section and nearby environment. The FBW fields for several different conductor geometries are analyzed. Superposition is used for conductor geometries that have multiple currents. A method for determining optimal field detector placement using optimization functions is introduced. Index Terms--Current sensing, field decoupling, giant magneto-resistive, magnetic field detectors, proximity effect, skin effect, superimposed fields.

Cardiac fibroblast (CF) proliferation and differentiation into hypersecretory myofibroblasts can lead to excessive extracellular matrix (ECM) production and cardiac fibrosis. In turn, the ECM produced can potentially activate CFs via distinct feedback mechanisms. To assess how specific ECM components influence CF activation, isolated CFs were plated on specific collagen substrates (type I, III, and VI collagens) before functional assays were carried out. The type VI collagen substrate potently induced myofibroblast differentiation but had little effect on CF proliferation. Conversely, the type I and III collagen substrates did not affect differentiation but caused significant induction of proliferation (type I, 240.7 [+ or -] 10.3%, and type III, 271.7 [+ or -] 21.8% of basal). Type I collagen activated ERK 1/2, whereas type III collagen did not. Treatment of CFs with angiotensin II, a potent mitogen of CFs, enhanced the growth observed on types I and III collagen but not on the type VI collagen substrate. Using an in vivo model of myocardial infarction (MI), we measured changes in type VI collagen expression and myofibroblast differentiation after post-MI remodeling. Concurrent elevations in type VI collagen and myofibroblast content were evident in the infarcted myocardium 20-wk post-MI. Overall, types 1 and II1 collagen stimulate CF proliferation, whereas type VI collagen plays a potentially novel role in cardiac remodeling through facilitation of myofibroblast differentiation. cardiac fibroblasts; fibrosis; extracellular matrix; [alpha]-smooth muscle actin