Search

Poison frogs acquire chemical defenses from the environment for protection against potential predators. These defensive chemicals are lipophilic alkaloids that are sequestered by poison frogs from dietary arthropods and stored in skin glands. Despite decades of research focusing on identifying poison frog alkaloids, we know relatively little about how environmental variation and subsequent arthropod availability impacts alkaloid loads in poison frogs. We investigated how seasonal environmental variation influences poison frog chemical profiles through changes in the diet of the Climbing Mantella (Mantella laevigata). We collected M. laevigata females on the Nosy Mangabe island reserve in Madagascar during the wet and dry seasons and tested the hypothesis that seasonal differences in rainfall is associated with changes in diet composition and skin alkaloid profiles of M. laevigata. The arthropod diet of each frog was characterized into five groups (i.e. ants, termites, mites, insect larvae, or other) using visual identification and cytochrome oxidase 1 DNA barcoding. We found that frog diet differed between the wet and dry seasons, where frogs had a more diverse diet in the wet season and consumed a higher percentage of ants in the dry season. To determine if seasonality was associated with variation in frog defensive chemical composition, we used gas chromatography / mass spectrometry to quantify alkaloids from individual skin samples. Although the assortment of identified alkaloids was similar across seasons, we detected significant differences in the abundance of certain alkaloids, which we hypothesize reflects seasonal variation in the diet of M. laevigata. We suggest that these variations could originate from seasonal changes in either arthropod leaf litter composition or changes in frog behavioral patterns. Although additional studies are needed to understand the consequences of long-term environmental shifts, this work suggests that alkaloid profiles are relatively robust against short-term environmental perturbations.

Introduction: Novel hemoperfusion systems are emerging for the treatment of sepsis. These devices can directly remove pathogens, pathogen-associated molecular patterns, cytokines, and other inflammatory markers from circulation. However, significant safety concerns such as potential antibiotic clearance need to be addressed prior to these devices being used in large clinical studies. Methods: Prospective, observational study of 34 participants undergoing treatment with the Seraph 100® Microbind Affinity Blood Filter (Seraph 100) device at 6 participating sites in the USA. Patients were included for analysis if they had a record of receiving an antibiotic concurrent with Seraph 100 treatment. Patients were excluded if there was missing information for blood flow rate. Blood samples were drawn pre- and post-filter at 1 h and 4 h after treatment initiation. These average pre- and post-filter time-concentration observations were then used to estimate antibiotic clearance in L/h (CLSeraph) due to the Seraph 100 device. Results: Of the 34 participants in the study, 17 met inclusion and exclusion criteria for the antibiotic analysis. Data were obtained for 7 antibiotics (azithromycin, cefazolin, cefepime, ceftriaxone, linezolid, piperacillin, and vancomycin) and one beta-lactamase inhibitor. Mean CLSeraph for the antibiotics investigated ranged from −0.57 to 0.47 L/h. No antibiotic had a CLSeraph statistically significant from 0. Discussion/Conclusion: The Seraph 100 did not significantly clear any measured antibiotic in clinical samples. These data give further evidence to suggest that these therapies may be safely administered to critically ill patients and will not impact concentrations of administered antibiotics. [ABSTRACT FROM AUTHOR]

The purpose of this study was to assess the self-efficacy of nursing faculty and students related to their potential use of mobile technology and to ask what implications this technology has for their teaching and learning in practice education contexts. We used a cross-sectional survey design involving students and faculty in two nursing education programs in a western Canadian college. In January, 2011, 121 faculty members and students completed the survey. Results showed a high level of ownership and use of mobile devices among our respondents. The median mobile self-efficacy score was 75 on a scale of 100, indicating that both faculty and students were highly confident in their use of mobile technologies and prepared to engage in mobile learning. (Contains 10 tables.)

This reflective case study was based on our independent use of the debate as an online instructional approach and our shared interest in teaching strategies. In an interdisciplinary manner, using narrative inquiry and action research, we melded our data sources and analyzed the findings, including our individual experiences with the technique. Our paper contributes to the field of research on faculty self-evaluations of teaching strategies, specifically debates. The topic will be of relevance to those who teach online. The findings suggest that examining faculty perceptions and views on the use of debates in text-based paced and un-paced courses at the online undergraduate and graduate levels can be a valuable undertaking. The process enabled us to benefit from our mutual reflective discussions on the use of debates to understand how each of us used the strategy. Despite our different approaches to the debate, we share many commonalities regarding debate as a teaching strategy.

We report here on an exploratory formative evaluation of a project to integrate mobile learning into a Western Canadian college nursing program. Third-year students used Hewlett Packard iPAQ mobile devices for five weeks in a practice education course in April-May, 2007. Koole's (2009) "Framework for the Rational Analysis of Mobile Education" (FRAME) model provided our definition of mobile learning and was used to organize our presentation of the results of the study. Participants reported positively on the usability of the mobile devices, finding them easy to learn, readily portable, and the screen size sufficient for mobile specific programs. However, they had difficulty with the wireless connectivity and, despite an initial orientation, did not have time to fully learn the devices in the context of a busy course. As a result, it is not clear if students can effectively use the social technology provided by such devices or if mobile learning can support interaction between instructors and learners in this context. The use of mobile devices in nursing practice education is feasible, but further investigation is needed on the use of m-learning for communication and interactive purposes. (Contains 2 figures, 6 tables and 1 note.)

Why do nursing and health studies graduate students who are enrolled in online programs decide to withdraw? The qualitative study reported in this paper investigated students' self-identified reasons for withdrawing from an online graduate program in nursing and health studies. The focus of the study was Athabasca Universities' Centre for Nursing and Health Studies (CNHS) online graduate program. Data were collected from program students who initiated withdrawal between the years 1999-2004. Using Rovai's (2002) Composite Persistence Model as a framework for analysis, themes identified from withdrawing students' notice of withdrawal letters are discussed. The major reasons for leaving can be placed into two categories, personal reasons (often related to life or work commitments) and program reasons (usually related to learning style and fit with career). These findings, and the resulting analysis, have implications for online program design and delivery and student support programs. With a better understanding of student reasons for leaving a program of studies, it will be possible to explore which program elements might be altered to improve the experience of online learning. (Contains 1 table.)