123 research outputs found
Use of The Flavor Profile Method To Solve Taste and Odor Problems in Water Supplies
The Flavor Profile Method (FPM) was evaluated for use as a practical tool to aid water managers in controlling taste and odor in water supplies. A sensory panel using students was organised and trained. Water samples from throughout the Orange Water and Sewer Authority water system were analysied by the sensory panel using the FPM. The FPM is useful in investigating the source of taste and odor problems and in monitoring the effectiveness of treatment processes in removing tastes and odors. The FPM is effective in eliminating the influence of outside odors on the results. A trained sensory panel using the FPM is able to detect presence of musty and chlorinous odorants in water samples in concentrations above a threshold value. Results from the sensory analysis of samples indicate an enhancement of the chlorinous flavor intensity in samples that were chlorinated with a musty odorant present.Master of Science in Environmental Engineerin
The only known cyclopygidââathelopticâ trilobite fauna from North America: the upper Ordovician fauna of the Pyle Mountain Argillite and its palaeoenvironmental significance
The trilobite fauna of the upper Ordovician (middle Katian) Pyle Mountain Argillite comprises a mixture of abundant mesopelagic cyclopygids and other pelagic taxa and a benthic fauna dominated by trilobites lacking eyes. Such faunas were widespread in deep water environments around Gondwana and terranes derived from that continent throughout Ordovician time but this is the only known record of such a fauna from North America and thus from Laurentia. It probably reflects a major sea level rise (the âLinearis drowning eventsâ) as does the development of coeval cyclopygid-dominated deep water trilobite faunas in terranes that were marginal to Laurentia and are now preserved in Ireland and Scotland. The Pyle Mountain Argillite trilobite fauna occurs with a deep water Foliomena brachiopod fauna and comprises 22 species. Pelagic trilobites (mostly cyclopygids) constitute 36% of the preserved sclerites, and 45% of the fauna is the remains of trilobites lacking eyes, including one new species, Dindymene whittingtoni sp. nov. Three species of cyclopygid are present, belonging in Cyclopyge, Symphysops and Microparia (Heterocyclopyge). Cyclopygids are widely thought to have been stratified in the water column in life and thus their taxonomic diversity reflects the relative depths of the sea-beds on which their remains accumulated. A tabulation of middle and upper Katian cyclopygid-bearing faunas from several palaeoplates and terranes arranged on the basis of increasing numbers of cyclopygid genera allows an assessment of the relative depth ranges of the associated benthic taxa. The Pyle Mountain Argillite fauna lies towards the deeper end of this depth spectrum
Endoskeletal structure in Cheirolepis (Osteichthyes, Actinopterygii), An early ray-finned fish
As the sister lineage of all other actinopterygians, the Middle to Late Devonian (EifelianâFrasnian) Cheirolepis occupies a pivotal position in vertebrate phylogeny. Although the dermal skeleton of this taxon has been exhaustively described, very little of its endoskeleton is known, leaving questions of neurocranial and fin evolution in early rayâfinned fishes unresolved. The model for early actinopterygian anatomy has instead been based largely on the Late Devonian (Frasnian) Mimipiscis, preserved in stunning detail from the Gogo Formation of Australia. Here, we present reâexaminations of existing museum specimens through the use of highâresolution laboratoryâ and synchrotronâbased computed tomography scanning, revealing new details of the neuroâcranium, hyomandibula and pectoral fin endoskeleton for the Eifelian Cheirolepis trailli. These new data highlight traits considered uncharacteristic of early actinopterygians, including an uninvested dorsal aorta and imperforate propterygium, and corroborate the early divergence of Cheirolepis within actinopterygian phylogeny. These traits represent conspicuous differences between the endoskeletal structure of Cheirolepis and Mimipiscis. Additionally, we describe new aspects of the parasphenoid, vomer and scales, most notably that the scales display pegâandâsocket articulation and a distinct neck. Collectively, these new data help clarify primitive conditions within rayâfinned fishes, which in turn have important implications for understanding features likely present in the last common ancestor of living osteichthyans
The stratigraphic distribution of the Ordovician inarticulate brachiopod Orthisocrania divaricata (M'Coy) in the British Isles
- âŠ