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Vascular flora and gradient analysis of the Natchez Trace ParkwayPhillips, Nena Mae Monique 02 June 2009 (has links)
Vascular plant collections were made on the Natchez Trace Parkway over a 15 month
period beginning in August 2004. These collections along with previous work done by the
National Park Service (NPS) produced a flora of 750 genera and 2196 species in 167 families.
Five collection trips were made so as to include as much of the growing season as possible
(August 2004, March, May, July and October 2005). Specimens were collected from 500 sites
along the Parkway as well as at 50 quadrat locations. The largest families, by species numbers,
are Asteraceae (298 species), Poaceae (236 species), Cyperaceae (148 species), Fabaceae
(133 species) and Rosaceae (73 species), which accounted for 40.4% of the flora.
A Detrended Correspondence Analysis (DCA) and TWINSPAN analysis were performed
on data collected from 49 sites along the length of the Natchez Trace Parkway (NATR). It was
found that the major environmental gradient (Axis 1) affecting the species composition of the site
was to be the level of disturbance. The sites with high levels of disturbance were characterized
as grassland field sites, while those areas with low levels of disturbance were characterized as
forested sites. The TWINSPAN analysis produced 29 groupings, of which eight were found to
be valid groupings.
Through the course of the study, almost 450 new species were added to the current
knowledge of the Natchez Trace Parkway by the NPS. In addition, one prospective endangered
species was located, which will aid the NPS in future management practices within the park.
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Effect of Trace Mineral Supplementation on Gastric Ulcers in Exercising Yearling HorsesHayes, Alexa Dawn 2009 August 1900 (has links)
Equine gastric ulcer syndrome (EGUS) has been reported to occur in 40% to over
90% of horses across multiple equestrian disciplines. The objective of this study was to
evaluate the effect of trace mineral supplementation on gastric ulcers in exercising
yearling horses. Twenty-one Quarter Horse yearlings, 15 to 18 mo of age, were
randomly assigned to 1 of 3 treatment groups. The control group received no
supplemental trace minerals, the inorganic group received supplemental sulfated trace
minerals, and the organic treatment received supplemental amino acid complexed trace
minerals. The trial consisted of 3 consecutive 28-d periods, separated by 5 d of diet
acclimation. The basal ration included a 14% CP textured concentrate, with coastal
Bermudagrass hay fed in Periods 1 and 3 and alfalfa consumed in Period 2. In Periods 1
and 2, horses were exercised on a mechanical horse-exerciser, but were lunged or
underwent training in an undergraduate course in Period 3. At the end of each period,
horses were transported for 6 h, 5 d before being endoscopically examined to assign
ulcer scores. Data were analyzed as repeated measures using the mixed procedure of SAS, with the model including fixed effects of treatment, period, and their interaction
(SAS 9.2). All P-values < 0.05 were considered significantly different.
Baseline EGUS scores were not different among treatment groups, with a mean
of 2.1. There was no effect of treatment in any period, or a period by treatment
interaction. There was a significant period effect (P < 0.01). Mean ulcer scores in
Periods 1, 2, and 3 were significantly lower than baseline, with mean scores of 1.5, 1.0,
and 1.5, respectively. There was a tendency (P=0.06) for mean ulcer scores to be lower
in Period 2 than in Periods 1 and 3, which were not different. Average daily intakes of
Zn, Mn, Cu, and Co were significantly higher in the organic and inorganic than control
horses (P < 0.0001).
Under the conditions of this study, trace mineral supplementation did not affect
gastric ulcer appearance and severity. However, it is possible that dietary and
management alternatives, such as hay and concentrate types, could be anti-ulcerogenic.
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A Real-Time Address Trace Compressor for Embedded MicroprocessorsHuang, Shyh-Ming 03 September 2003 (has links)
Address trace compression represents that the address data, which are generated from the instruction fetch stage of the microprocessor, can be retrieved for later observation and analysis. This real time trace compression hardware is the primary component of real-time trace system. In this paper, we present how to design and implement this real-time address trace compressor. Address trace compressor is allowed to perform accurate, successive trace collection in an unlimited length and can be used in various embedded microprocessors without influencing the operation of the microprocessors. Also, it has abundant reconfigurable parameters that can be used to develop a cost-effective trace system. The experiment results show that this compressor can reach a higher compression ratio of 1:100. Hence, by utilizing this real-time compression technique, the trace depths of new trace system can be 20 times more than these existing in-circuit emulators.
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Trace metal uptake and accumulation pathways in Kemp's ridley sea turtles (Lepidochelys kempii)Wang, Hui-Chen 29 August 2005 (has links)
Little is known of trace metal concentrations and their possible role in the
mortality of critically endangered Kemp??s ridley sea turtles (Lepidochelys kempii).
Research described herein characterized concentrations of seven trace metals ??
Ag, Cd, Cr, Cu, Hg, Pb and Zn ?? in the blood and carapace tissue of captive
Kemp??s ridleys for use in assessing levels of these metals in wild counterparts.
Concentrations of same trace metals were characterized in post-pelagic through
adult life stages of 127 wild Kemp??s ridleys captured from the Gulf of Mexico and
southeast Atlantic during 2000 to 2002. Blood, carapace, liver, kidney, and
muscle tissues from live and/or stranded Kemp??s ridleys were analyzed for the
aforementioned trace metals via graphite furnace atomic absorption
spectrophotometer and cold vapor atomic fluorescence techniques conducted
under class-100 clean laboratory conditions. Similar trace metal assessments
were conducted on blue crab (Callinectes sapidus) prey to determine the role of
food as a possible uptake pathway in Kemp??s ridleys.
Overall, trace metal levels in live, captive as well as wild ridleys were higher
in carapace tissue than in blood. Carapace concentrations of Ag, Cr and Hg in
Kemp??s ridleys across all post-pelagic life stages increased with increasing
straight carapace length (SCL). Carapace tissue of wild ridleys exhibited higher
Cr, Hg, and Pb levels than their blue crab prey, regardless of study area;
whereas, crabs yielded higher Ag and Cu concentrations. Dead stranded ridleys
yielded higher Ag, Cr, Hg, Pb, Zn levels in carapace tissue, whereas, their liver
exhibited higher Cd and Cu levels. This finding suggests carapace tissue could
serve as a suitable surrogate sample source for internal organs/tissues when
monitoring exposure of live Kemp??s ridleys to certain metals. The fact that larger,
stranded ridleys exhibited higher Ag, Cd, Hg, Pb and Zn levels than did their
smaller, live analogs from Texas and Louisiana implies that these older ridleys
had increased opportunities to accumulate higher metal concentrations in their
carapace tissue than did their younger conspecifics. This trend suggests that
carapace tissue has the potential to accumulate trace metals while blood-borne
concentrations reflect only recent exposure to trace metals.
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Controls of Trace Metal Distributions in the Kaoping Coastal ZoneHo, Chuang-yi 24 July 2008 (has links)
This study investigates the distributions of trace metals and their controlling mechanisms in the Kaoping coastal zone. Concentrations of most dissolved metals were generally lower in the wet season than in the dry season in the Kaoping Estuary, showing clearly the effects of river discharge rate and water residence time on metal distributions. Dissolved trace metals (Fe, Mn, Zn, Cu, Cd and Pb) behaved non-conservatively with addition in the estuary. Nevertheless, dissolved Pb was apparently removed from the estuary in the wet season. Particulate Al and Fe were derived mainly from continental weathering and their transports through the estuary depend highly on the distribution of total suspended matter (TSM). During the dry season, the occurrence oxygen-deficit condition in the low salinity region and possible pollution from the San-Wei fishery harbor likely determined the distributions and solid-solution partitions of Mn, Zn, Cu, Cd and Pb in the estuary.
Distributions of dissolved trace metals in the Kaoping coastal zone were significantly influenced by terrestrial inputs from the Kaoping River. Seasonal variations were attributed largely from the mixing between river water and sea water in the mixing layer and sediment resuspension from canyon bed. The column integrated dissolved and particulate metals were generally higher in the summer season than in other seasons. The difference was especially pronounced in nearshore stations. Concentrations of dissolved Mn, Zn, Cu and Pb increased generally with depth, reflecting the effects of resuspension and lateral transport of bottom sediment. Dissolved Zn and Cu concentrations correlated well with dissolved Mn concentration, but particulate Zn and Cu correlated poorly with particulate Al, implying that distributions of Zn and Cu were controlled by terrestrial inputs and biogeochemical processes in the Kaoping Canyon. Positive and negative correlations are found between dissolved Cd and nutrients (N+N¡Aorthophosphate) and between dissolved Cd and dissolved organic carbon (DOC), respectively, indicating that Cd is a nutrient-type metal and controlled biogeochemically in the Kaoping Canyon.
Specific events such as typhoon and earthquake influenced significantly the distributions of trace metals in the Kaoping coastal zone. The integrated suspended-matter and suspended-metal concentrations showed an order magnitude higher during the typhoon season than in the normal summer season. Under the influence of earthquake, the TSM values of the bottom waters were much higher (2-7 folds) during the post- earthquake cruise (Jan/2007) than in the normal season (Jan/2006). Meanwhile, particulate Al, Fe, and Mn can increase up to 2- to 10-folds after earthquake in the bottom layer of canyon.
Metal enrichment factor (EF) is an indicator of metal pollution. The EFs show an order magnitude higher in the dry season than in the wet season both in the estuary and canyon. Such seasonal patterns clearly indicate the impacts of local and river inputs on metal distributions in the estuary and canyon.
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Using ichnology and sedimentology to determine paleoenvironmental and paleoecological conditions of a shallow-water, marine depositional environment case studies from the Pennsylvanian Ames limestone and modern holothurians /Smilek, Krista R. January 2009 (has links)
Thesis (M.S.)--Ohio University, August, 2009. / Title from PDF t.p. Includes bibliographical references.
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The genesis of natrocarbonatites : constraints from experimental petrology and trace element partitioning /Petibon, Caroline Marie, January 1999 (has links)
Thesis (Ph.D.), Memorial University of Newfoundland, 2000. / Bibliography: leaves R-1-R-17. Also available online.
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Assessment of trace element contamination in streambed sediment and spatial associations in Palolo Valley watershed, Honolulu, Oʻahu, HawaiʻiHotton, Veronica K. January 2005 (has links)
Thesis (M.A.)--University of Hawaii at Manoa, 2005. / Includes bibliographical references (leaves 146-156).
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Assessment of trace element contamination in streambed sediment and spatial associations in Palolo Valley watershed, Honolulu, Oʻahu, Hawaiʻi /Hotton, Veronica K. January 2005 (has links)
Thesis (M.A.)--University of Hawaii at Manoa, 2005. / Includes bibliographical references (leaves 146-156). Also available via World Wide Web.
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Efficacy of hair mineral analysis for assessing zinc statusHavey, Shawn Michael. January 2009 (has links)
Thesis (M.S.)--Rutgers University, 2009. / "Graduate Program in Chemistry." Includes bibliographical references (p.54-56).
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