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Author (up) Clayton, J.A.; Knox, J.C. file  url
doi  openurl
  Title Catastrophic flooding from Glacial Lake Wisconsin Type Journal Article
  Year 2008 Publication Geomorphology Abbreviated Journal Geomorphology  
  Volume 93 Issue 3-4 Pages 384-397  
  Keywords Glacial Lake Wisconsin; Catastrophic flooding; Geomorphology; Paleohydrology  
  Abstract Glacial Lake Wisconsin was a large proglacial lake that formed along the southern margin of the Laurentide Ice Sheet during the Wisconsin glaciation. It was formed when ice of the Green Bay Lobe came into contact with the Baraboo Hills in southwestern Wisconsin and blocked the south-flowing Wisconsin River. During early glacial recession, the ice dam failed catastrophically and the lake drained in about a week. Despite early recognition of the former lake and the likelihood that it failed catastrophically, outflow rates during the failure have not been previously evaluated. Estimates based on step-backwater modeling indicate that peak discharge was between 3.6 and 5.3 × 104 m3/s in the lower Wisconsin River. As an alternate method, we used a previously derived empirical relationship between lake volume and peak discharge for dam-break events. From a digital elevation model altered to incorporate isostatic depression, we estimated the lake volume to be 87 km3 just prior to dam breach, suggesting that the flooding magnitude was as high as 1.5 × 105 m3/s at the outlet. Adjusting these results for downstream flood wave attenuation gives a discharge of around 4.4 × 104 m3/s in the lower reach, which closely matches the results of the step-backwater modeling. These estimates of discharge from the catastrophic failure of ice-marginal lakes improve our understanding of the processes that have produced the morphology and behavior of present-day upper Midwest river systems.  
  Call Number Serial 718  
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Author (up) Kralj Kuncic, M.; Zajc, J.; Drobne, D.; Pipan Tkalec, Z.; Gunde-Cimerman, N. file  url
doi  openurl
  Title Morphological responses to high sugar concentrations differ from adaptation to high salt concentrations in the xerophilic fungi Wallemia spp Type Journal Article
  Year 2013 Publication Fungal Biology Abbreviated Journal Fungal Biol  
  Volume 117 Issue 7-8 Pages 466-478  
  Keywords Ascomycota/classification/*growth & development/*metabolism/ultrastructure; Cell Wall/metabolism/ultrastructure; Culture Media/chemistry/metabolism; Glucose/analysis/*metabolism; Honey/*analysis/microbiology; Microscopy, Electron, Scanning; Sodium Chloride/analysis/*metabolism; Cell wall; Cellular aggregates; Glucose; Honey; Morphology; Osmotic stress  
  Abstract Fungi from the food-borne basidiomycetous genus Wallemia, which comprises Wallemia ichthyophaga, Wallemia muriae and Wallemia sebi, are among the most xerophilic organisms described. Their morphological adaptations to life at high NaCl concentrations are reflected in increased cell-wall thickness and size of cellular aggregates. The objectives of this study were to examine their growth and to define cell morphology and any ultrastructural cell-wall changes when these fungi are grown in low and high glucose and honey concentrations, as environmental osmolytes. We analysed their growth parameters and morphological characteristics by light microscopy and transmission and scanning electron microscopy. Wallemia ichthyophaga grew slowly in all of the sugar-based media, while W. muriae and W. sebi demonstrated better growth. Wallemia ichthyophaga adapted to the high glucose and honey concentrations with formation of larger cellular aggregates, while cell-wall thickness was increased only at the high glucose concentration. Wallemia muriae and W. sebi demonstrated particularly smaller sizes of hyphal aggregates at the high glucose concentration, and different and less explicit changes in cell-wall thickness. Adaptive responses show that the phylogenetically more distant W. ichthyophaga is better adapted to high salt conditions, whereas W. muriae and W. sebi cope better with a high sugar environment.  
  Call Number Serial 1138  
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Author (up) Lee, A.H.; Eme, J.; Mueller, C.A.; Manzon, R.G.; Somers, C.M.; Boreham, D.R.; Wilson, J.Y. file  url
openurl 
  Title The effects of increased constant incubation temperature and cumulative acute heat shock exposures on morphology and survival of Lake Whitefish (Coregonus clupeaformis) embryos Type Journal Article
  Year 2016 Publication Journal of Thermal Biology Abbreviated Journal J Therm Biol  
  Volume 57 Issue Pages 11-20  
  Keywords Climate change; Coregonus clupeaformis; Great Lakes; Heat shock; Morphology; Survival; Temperature; Thermal effluent  
  Abstract Increasing incubation temperatures, caused by global climate change or thermal effluent from industrial processes, may influence embryonic development of fish. This study investigates the cumulative effects of increased incubation temperature and repeated heat shocks on developing Lake Whitefish (Coregonus clupeaformis) embryos. We studied the effects of three constant incubation temperatures (2 degrees C, 5 degrees C or 8 degrees C water) and weekly, 1-h heat shocks (+3 degrees C) on hatching time, survival and morphology of embryos, as these endpoints may be particularly susceptible to temperature changes. The constant temperatures represent the predicted magnitude of elevated water temperatures from climate change and industrial thermal plumes. Time to the pre-hatch stage decreased as constant incubation temperature increased (148d at 2 degrees C, 92d at 5 degrees C, 50d at 8 degrees C), but weekly heat shocks did not affect time to hatch. Mean survival rates and embryo morphometrics were compared at specific developmental time-points (blastopore, eyed, fin flutter and pre-hatch) across all treatments. Constant incubation temperatures or +3 degrees C heat-shock exposures did not significantly alter cumulative survival percentage (~50% cumulative survival to pre-hatch stage). Constant warm incubation temperatures did result in differences in morphology in pre-hatch stage embryos. 8 degrees C and 5 degrees C embryos were significantly smaller and had larger yolks than 2 degrees C embryos, but heat-shocked embryos did not differ from their respective constant temperature treatment groups. Elevated incubation temperatures may adversely alter Lake Whitefish embryo size at hatch, but weekly 1-h heat shocks did not affect size or survival at hatch. These results suggest that intermittent bouts of warm water effluent (e.g., variable industrial emissions) are less likely to negatively affect Lake Whitefish embryonic development than warmer constant incubation temperatures that may occur due to climate change.  
  Call Number Serial 1227  
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Author (up) Rogers, H.H.; Peterson, C.M.; McCRIMMON, J.N.; Cure, J.D. file  url
openurl 
  Title Response of plant roots to elevated atmospheric carbon dioxide Type Journal Article
  Year 1992 Publication Plant, Cell and Environment Abbreviated Journal Plant Cell Environ  
  Volume 15 Issue 6 Pages 749-752  
  Keywords Glycine max; soybean; CO2 enrichment; root architecture; root micromorphology  
  Abstract Plant root response to atmospheric CO2 enrichment can be great. Results from this controlled environment investigation demonstrate substantial effects on root system architecture, micromorphology and physiology. The most pronounced effects were an increase in root length (110%) and root dry weight (143%). Root diameter, stele diameter, cortex width, root/shoot and root weight ratios all increased; root numbers did not increase. The long-term implications for belowground processes could be enormous.  
  Call Number Serial 1638  
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Author (up) Ruiz Carrasco, K.B.; Baroni Fornasiero, R.; Tassoni, A.; Bagni, N. url  openurl
  Title Identification of two phenotypes of Arabidopsis thaliana under in vitro salt stress conditions Type Journal Article
  Year 2007 Publication Biologia Plantarum Abbreviated Journal Biol Plant  
  Volume 51 Issue 3 Pages 436-442  
  Keywords Chlorophyll; Leaf anatomy; Morphology; Proteins; Sodium chloride  
  Abstract This study describes two phenotypes of Arabidopsis thaliana (ecotype Columbia) developed in vitro under salt stress (75 mM NaCl). The phenotypes 01 and 02 appeared visibly distinguishable by rosette morphology and competence to produce flowers. Phenotype 01, sensible to salt stress, accumulated high quantities of Na+, showed a slight reduction in dry mass, and high protein and chlorophyll contents. Moreover, its anatomy exhibited some xeromorphic traits. Phenotype 02, clearly salt tolerant, showed a morphology similar to control plants, displaying typical phyllotactic rosette and flowering stalk production. Accumulation of Na+, protein and chlorophyll contents were close to control plants. Reversion experiments on NaCl free MS medium, showed a partially recovered phenotype 01. A threshold salt stress concentration that permits the simultaneous development of two phenotypes, was found.  
  Call Number Serial 685  
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