At the meeting of the First International Symposium on Arctic Geology held in Calgary, Alberta, Canada, a number of original papers on this topic were presented, and essentially all of them are ...printed in the pages ofThe Geology of the Arcticvolumes I and II.
Evidence that Ichthyophthirius multifiliis trophonts may reproduce within the epithelium of the host was obtained from experimental infections of channel catfish. Mean number of parasites ...spontaneously leaving the fish increased from 0 on day 3 postexposure (PE) to 66.5 per fish on day 7 PE. Mean population density in fin, however, increased five-fold from day 3 to day 5 PE in the absence of opportunity for reinfection. At day 3 PE, 100% of parasite loci in fin and gill arches contained solitary trophonts. At day 4 PE, 10% of loci in fin contained clusters of two trophonts; at day 7 PE, 69% contained clusters of two or more trophonts. The first clusters of four trophonts in fin were observed day 5 PE and of eight trophonts, day 8 PE. Trophonts in clusters were flattened against one another.
Because infection with Ichthyophthirius multifiliis has been reported to result in osmotic stress, genesis of the plasma chloride and chloride cell response of channel catfish Ictalurus punctatus to ...the infection was studied from day 0 to day 7 postexposure (PE). Parasite population densities ranged from 0.08 to 0.22 trophonts per gill filament during days 1–5 PE and increased to 2.1 at day 7 PE. Population increases were the result of infection by a new generation of infective theronts and reproduction by the parasite on the host. Mean plasma chloride concentrations of fish were not significantly different among days 0–5 PE (range of means, 93.01–97.87 meq/L), but by day 7 PE the mean had declined significantly, to 83.73 meq/L. Maintenance of relatively stable plasma chloride concentrations for 5 d was associated with chloride cell proliferation. The number of interlamellar filament chloride cells had significantly increased by day 1 PE, and the number of chloride cells in the lamellae had significantly increased by day 5 PE. No further increase had occurred by day 7 PE. Vacuolization of chloride cells, examined by electron microscopy, became more common as infection progressed, and many chloride cells appeared to be degenerating by day 5 PE.
The purpose of this study was to determine if (1) levels of water literacy differed between college freshman nonscience majors having 1 versus 2 years of high school science coursework, (2) visual ...imagery exercises could improve understanding of evaporation and condensation related to the water cycle, and (3) patterns exist in the concept of the water cycle. There was no statistically significant difference in water knowledge between entering freshmen with 1 versus 2 years of high school science coursework. The use of visual imagery was found to improve comprehension of condensation and evaporation (p < .0001), and for these college nonscience majors, alternative conceptual frameworks were similar to those for other populations reported on in the literature.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Using deconvolution, ion mobility peak shape was found to be dependent upon the nature of the compound, moisture of the drift gas, and acquisition temperature (water clustering) over processes such ...as ion scavenging and diffusion. Under low moisture conditions, the nature of the compound had greater impact upon peak shape than experimental variables such as temperature. When coeluting compounds were introduced into the mobility spectrometer, peak shape and deconvolution performance were dependent upon the above factors as well as relative concentrations, proton affinities, and differences in the drift times of the mobility peaks of individual components. Deconvolution coupled with atmospheric pressure chemical ionization mass spectrometry was employed for interpretation of mixed component mobility spectra.
CHAPTER 8: The Power of Girls Kaufman, Judith S.; Ewing, Margaret S.; Montgomery, Diane M. ...
Counterpoints (New York, N.Y.),
01/2003, Letnik:
116
Journal Article
CHAPTER 6: Making New Meaning: Creative Acts Kaufman, Judith S.; Ewing, Margaret S.; Montgomery, Diane M. ...
Counterpoints (New York, N.Y.),
01/2003, Letnik:
116
Journal Article
CHAPTER 5: Metaphor: Girls in Their Elements Kaufman, Judith S.; Ewing, Margaret S.; Montgomery, Diane M. ...
Counterpoints (New York, N.Y.),
01/2003, Letnik:
116
Journal Article
