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Does Aquaporin 3b Affect The Number and Characteristics of Calcium Waves in The Neural Plate of Xenopus Laevis Embryos?
No full textEarly in the development of the nervous system, vertebrate embryos undergo neural tube closure. During this process, the cells in the dorsal part of an embryo, the neural plate, constrict on their outward facing side (apical constriction) to form a tube. The Merzdorf lab has found that expression of the Aquaporin 3b (Aqp3b) protein in Xenopus laevis (African clawed frog) embryos is critical for neural tube closure, specifically for apical constriction of the cells of the neural plate. While aqp3b is only expressed in a well-defined line along the outer edge of each side of the neural plate, it affects a pan-neural plate process. Thus, the question my study attempts to answer is how Aqp3b signals to the rest of the neural plate. A likely candidate for the signal is calcium, a common intercellular and cellular signal. I hypothesize that the neural plate in embryos with inhibited Aqp3b expression will have fewer calcium waves and/or calcium waves with different characteristics. To test this hypothesis, the number and characteristics of calcium activity will be compared between control embryos and embryos that have been inhibited from expressing Aqp3b. This is accomplished by injecting a morpholino oligonucleotide, which inhibits Aqp3b expression, and GCaMP6, which is fluorescent in the presence of calcium, into frog embryos at the four-cell stage. I then collect time lapses of calcium activity that occurs during neural tube closure and analyze them for differences in the length, period, intensity, etc. of calcium signaling events using a variety of software. As my project continues, I will continue to collect data and begin to draw a conclusion on it
Effects of Rangeland Management on the Ecology of Sharp-Tailed Grouse in Mixed-Grass Prairies
No full textTemperate grasslands, including mixed-grass prairies, suffer from the greatest levels of habitat loss and degradation of any ecosystem, which can have cascading negative effects. Grazing by livestock is the predominant land use across western North America and directly affects the structure, composition, and productivity of native grasslands. While certain grazing regimes can negatively affect wildlife habitat, properly managed grazing can be compatible with wildlife conservation and is preferable to other land uses that destroy or fragment native grasslands. With large home ranges and differing requirements for nesting and winter habitat, sharp-tailed grouse (Tympanuchus phasianellus) require large and complex areas of habitat, making them an ideal indicator species for grassland habitats. Poor range management has been implicated in the decline of sharp-tailed grouse throughout North America, but the effects of specific grazing regimes on grouse populations have not been studied. A better understanding of the ecological impacts of grazing is required to develop effective conservation strategies. We monitored 203 radio-collared sharp-tailed grouse in eastern Montana to assess the effects of grazing management on grouse ecology and evaluate the effectiveness of specific grazing regimes for improving wildlife habitat. In three years of study, we found that choice of grazing system had no effect on space use and important vital rates (nest survival and adult survival) for sharp-tailed grouse. We observed relatively weak effects of stocking rate and stocking density, but overall the performance of the sharp-tailed grouse population at our study area was not affected by grazing system. 
Young and Restless - A Guide to Getting Your Own Colony as a Juvenile Beaver
No full textInterest in using beavers (Castor spp.) as an efficient riparian restoration tool has increased dramatically in recent decades. The ultimate goal of most beaver-mediated habitat restoration projects is to establish a self-sustaining population of beavers that can occupy new habitats over time. Therefore, dispersal is a key process to understand when evaluating the potential for project locations to be settled by beavers. We radio-marked juvenile beavers in the Gallatin and Madison River drainages in southwest Montana to investigate dispersal characteristics, survival, and settlement site selection. Our goal was to improve identification of restoration sites with the highest probability of colonization by beavers. The annual probability of dispersal in our study area was low (0.26 ± 0.24-0.29), and distances and timing of dispersal were highly variable. The probability of a beaver dispersing decreased as local colony density increased, suggesting delayed dispersal. Few radio-marked beavers started new colonies in previously unoccupied habitat during our study. Instead, most dispersers settled in stream segments already modified by previous beaver activity. The low number of new settlement sites and evidence of delayed dispersal suggests most of the suitable habitat in our study area was occupied. We recommend land and wildlife managers assess the density and distribution of beaver colonies around proposed restoration sites prior to project design to evaluate the potential for dispersal into the project area. Beaver dispersal is an important factor in the success of riparian restoration projects, and our work highlights aspects of dispersal that may influence beaver settlement in this context
A Message from the President
Get PDFWelcome to the PNLA Quarterly conference issue! The 2017 PNLA conference was held in Post Falls, Idaho, and showcased the wonderful and innovative work happening in libraries across the region
The Mentor: Finding a Mentor
Get PDFEditor’s note: The Mentor column is a place for advice, storytelling, introspection, and professional growth
From Safe Spaces to Brave Spaces: Rethinking How We Talk About Diversity in the Library Profession and Learning from Failure
Get PDFThe election, and what’s happened after, have convinced me that we need to start talking more openly about diversity within the library profession and how to dismantle the struc-tural barriers that exist and persist within librarianship as well as society as a whole
Fecal vs. Rumen Contents to Determine White-tailed Deer Diets
Get PDFThe purpose of this study was to evaluate and determine the feasibility of white-tailed deer (Odocoileus virginianus) diet composition of rumen versus fecal contents during winter months in the Black Hills of South Dakota. Sixty-two deer were shot over five winters (December – May). Major plant composition was approximately the same; however, juniper, pine, lichen, and Astragalus species showed significant differences between fecal and rumen comparisons. Spearman rank order correlation indicated ranks were in good agreement (r = 0.82, P = 0.01). Average Kulczynki’s similarity was 75 percent overall and is considered very good for major forage species. Significant differences were observed for shrubs and lichen when considering all forage species.. Overall, fecal analyses for major forage species will provide excellent information and help managers make more informed decisions with regard to habitat resources for deer.
Key words: diet composition, methods, microhistological, forage, plant
Characterizing Excited State Diffusion in PCDTBT Using Transient Absorption Microscopy
Get PDFOrganic semiconducting polymers (OSPs) are an attractive alternative to traditional inorganic semiconductors for use in photovoltaic devices and other optoelectronic applications because they are cost effective and solution processable. Here we describe our efforts towards under-standing excited state transport in micron-scale domains of the OSP, poly [N-9’’-hepta-decanyl-2,7-carbazole-alt-5,5-(4’,7’-di-2-thienyl-2’,1’,3’-benzothiadiazole)] (PCDTBT) utilizing transient absorption microscopy (TAM). Using TAM, we directly image excited state diffusion across mi-cron scale domains of PCDTBT thin films, reducing the effects of morphological heterogeneity in these complex polymeric systems. To further understand exciton diffusion and dissociation dynamics we have begun the development of two individual experiments. This presentation will discuss the theoretical evaluation of both experiments as well as preliminary experimental development. The first experiment has been investigated by Monte Carlo simulation of exciton dissociation at microfabricated donoracceptor interfaces. The second experiment relies on the fabrication of polymer devices so that carrier diffusion can be characterized under the influence of an electric field. Investigation and implementation of these experiments was made possible by support from the Montana Academy of Sciences and will provide a more thorough understanding of the excited state transport dynamics in micron scale regions of PCDTBT
Investigating The Role Of Dnc-2 And Dli-1 On Ampa Receptor Mediated Behaviors In C. Elegans
Get PDFγ-amino-3-hydroxy-5methylisoxazole-4-proprionic acid (AMPA) receptors (AMPARs) are protein complexes involved in excitatory neurotransmission. AMPARs are tetrameric structures consisting of the pairings of GluA1, GluA2, GluA3, and GluA4 subunits. Dctn2 and Dync1li1 were found to interact with GluA2 in an immunoprecipitation screen that was performed on postnatal day 14 rat brains. DNC-2 and DLI-1 were identified as the C. elegans homologs of Dctn2 and Dync1li1, respectively, and are components of motor proteins that transport cargo throughout the cell. The goal of this project was to determine whether knocking down DNC-2 and DLI-1 by RNAi affects AMPA Receptor-mediated behaviors, including mechanosensation and chemosensation, in C. elegans