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Aplikace Fin Ray principu pro automatizaci výrobních procesů / Application of Fin Ray approach for production process automationPfaff, Ondřej January 2010 (has links)
This dissertation is about manipulating equipments using Fin Ray Effect ®. The model of manipulator, using this principle, was created for description of the manipulator movement. The measurement was done with this model. After result evaluation the improvement of model was proposed. There were also proposed technical applications where this type of manipulation could be used.
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The Role of 5’ hox13 Genes in Danio rerio (Zebrafish) Caudal Fin Ray/Joint Development and RegenerationQuigley, Hailey 21 April 2021 (has links)
Zebrafish are part of the teleost infraclass (bony fish) of the ray-finned fish. Like other teleosts, zebrafish possess the ability to regenerate most tissues, including their fins. Zebrafish fins contain segmented bony fin rays that longitudinally span the fin. The segments of fin ray are separated by fibrous joints at regularly spaced intervals providing segmentation and flexibility for the fin. Based on gene expression and changes in cell morphology, joint cell differentiation during development and regeneration proceeds through three stages: presumptive joint, joint-forming, and mature joint cells. Our lab has shown that new joint formation correlates with the upregulation of 5’ hoxa gene, hoxa13a. The hox genes encode transcription factors important for patterning in development. In mice, phenotypes resulting from loss- and gain-of-function mutations in Hox genes have revealed that the spatiotemporal expression of these genes is critical for the correct morphogenesis of the limb, a homologous structure to the fin. The first experiments in this thesis use the NTR/MTZ mechanism to partially ablate hoxa13a-expressing cells in the joints and blastema of the regenerating caudal fin. Partial ablation of the hoxa13a-expressing cells results in shorter bone segments following regeneration of the fin. This experiment draws the conclusion that hoxa13a-expressing cells are involved in the regulation of segment length. To examine the function of the 5’ hoxa/d genes in zebrafish, our lab created CRISPR/Cas9 mutations that inactivate hoxa13a, hoxa13b, and hoxd13a. The triple mutants created through serial breeding, show fin-specific defects in the formation and patterning of joints, as well as general defects in the morphology of the ray and in the actinotrichia, collagenous fibres found at the distal edge of the fin. Overall, our data suggest that hox13 genes are necessary for joint formation and proper fin ray growth. With further phenotypic and genotypic analyses our lab proposes that the dosage of hox13 alleles is responsible for anomalies in fin ray formation found in hox13 mutants.
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SCAPHIRHYNCHUS STURGEON EARLY-LIFE HISTORYPhelps, Quinton Edward 01 August 2011 (has links)
Rehabilitation of sturgeon populations requires an understanding of sturgeon autecology during all life stages, especially during early life when high mortality occurs. To begin to understand sturgeon early-life history I determined river of origin on a multi-basin scale (i.e., potential rivers of origin). I then determined habitat needs and early life demographics on a more localized scale (i.e., specific river). Trace elements differ between river reaches of the central US and may be used to determine origin of age-0 sturgeon. My trace element analyses suggested that age-0 sturgeon captured in the Middle Mississippi River, which extends from the confluence of the Missouri River downstream to the confluence of the Ohio River, drifted from as far upstream as the Gavins Point Dam on the Missouri River (> 1200 km), while other individuals originated locally in the Middle Mississippi River. On a more refined scale of habitats, I used trawling to identify habitat features used. Age-0 Scaphirhynchus sturgeon catch rates were highest around artificial structures (i.e., wing dikes) and island areas while main channel habitat comprised the lowest catch rates. Within these habitats, young sturgeon frequently occupied low velocities (i.e., ~0.1), moderate depths (i.e., 2 to 5 m), and sand substrate. Although determination of river of origin and specific habitats used are imperative for restoration, sturgeon populations are likely regulated by factors within habitats that affect early-life dynamics. Mean sturgeon growth rates ranged from 1.42-1.50 mm/d over the four years but did not differ among years. Individuals hatched over a 25 to 50-d period and peak hatch dates were between 10- 20 May during all years. Hatching coincided with optimum spawning temperatures of 17-20oC and a rise in river stage. Abundance was positively related to river stage, with longer durations of high water related increasing abundance. Mortality of age-0 sturgeon increased with the number of days where water temperature exceeded 28 oC. In the end this study has set benchmarks for understanding factors affecting the early-life ecology of Scaphirhynchus sturgeon.
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Evaluation of fin ray and fin spine chemistry as indicators of environmental history for five fish speciesSmith, Kurt Thomas 01 December 2010 (has links)
Knowledge of environmental history is important for the management and conservation of fish populations. Multiple methods to tag or mark fish have been developed (e.g., radio transmitters, coded wire tags, PIT tags, genetic markers), however, each of these methods has limitations. Naturally occurring and artificial chemical markers in otoliths have recently been used to determine natal origins and environmental history of fishes in both marine and freshwater environments and are not subject to the shortcomings of conventional tagging methods. However, few studies have evaluated the application of fish fin rays as a non-lethal alternative to fish otoliths as a recorder of individual fish environmental history. Therefore, I evaluated the application of artificial and naturally occurring chemical markers in fish fin rays as tracers of individual environmental histories. Specifically, I sought to determine 1) if age-0 lake sturgeon pectoral fin rays could be marked by immersion in strontium carbonate (SrCO3) enriched with the stable isotope 86Sr (86SrCO3), 2) whether natural differences in otolith and fin spine chemistry are present in catfish species collected from the Mississippi River basin, and 3) whether natural differences in fin ray chemistry are present in smallmouth bass from different rivers and streams in northern Illinois. Results from the first objective indicated that age-0 lake sturgeon were marked with 83% success when reared in water enriched with 100 µg/L of 86SrCO3, compared to control fish, and mark retention was maintained for at least 120 d following the labeling period. Results of the second objective indicated that both catfish otolith Sr:Ca, δ18O, and δ13C and fin spine Sr:Ca differed among sites, reflecting geographic differences in water chemistry at source locations. Both structures classified fish to their environment of capture with a high degree of accuracy, except in the Middle and Lower Mississippi Rivers where many recent immigrants appeared to be present. Similarly, smallmouth bass fin ray core Sr:Ca differed among sites, reflecting previously documented differences in water chemistry among streams and rivers in northern Illinois. Classification accuracy of smallmouth bass to their environment of capture based on fin ray Sr:Ca was variable, as some rivers had similar water chemistry signatures. The use of artificial chemical marks in fin rays will be useful when marking small fish that may not respond well to physical tags, when non-lethal recovery is desirable, and to distinguish between multiple batches of stocked fish (i.e. to evaluate factors such as stocking location and timing, fish size, and when fish may become interspersed into the existing population). Natural chemical signatures in pectoral fin rays or fin spines may provide a non-lethal alternative to otoliths for gathering information on environmental history (e.g. stock mixing, recruitment sources) of smallmouth bass and catfishes, consistent with recent demonstrations of this technique's effectiveness in other fish species. Ultimately, the use of artificial and naturally occurring chemical marks in fish fin rays provides a non-lethal alternative method to evaluate the environmental history of all life stages of fish
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Novel Techniques in Chemical Ecology to Examine Life Histories in FishesTzadik, Orian 29 March 2016 (has links)
Diet and movements in fishes are often logistically challenging to study. Trace element and stable isotope analyses have advanced these fields considerably, but are still constrained by methodological impediments, such as the tendency towards lethal sampling. Studying endangered fishes is particularly challenging as representative samples are difficult to obtain. However, the information gained from such studies is often critical to the recovery of endangered fishes as knowledge of life history attributes has the potential to greatly influence the success of management strategies.
I tested the viability of using fin rays in fishes as a non-lethal approach to study diet and movement patterns over time. I then applied the methods I developed to study the life history of the critically endangered Goliath Grouper, Epinephelus itajara. Fin ray analyses have traditionally been used in age and growth studies, as well as in a limited number of projects that study the chemical constituents of the ray itself. Therefore, I first tested whether fin rays could be used as chronological recorders of chemical properties over time using a pseudo-experimental design. By using samples from various aquaria, I had documentation of the time of capture of every animal used. Based on the assumption that the otolith in fishes represents a conserved, chronological matrix, I compared trace element concentrations between the otolith and the fin ray of each individual. In addition I tested whether stable isotope values of δ13C and δ15N differed between the wild and captive life phases of each individual. Divalent ions and positively-charged transition metals (e.g., Fe, Co) in particular showed strong associations between the two structures, suggesting conservation of material. Stable isotope values of δ13C and δ15N differed between the wild and captive life phases in most of the fishes sampled, also suggestive of conserved matrices.
I then tested and modeled the differences in δ15N values over time between the populations of Goliath Groupers on the west and east coasts of Florida. In general, individuals on the west coast had lower overall values and a larger difference between juvenile and adult values. The mechanism that caused the differences between coastal populations may have been an artifact of the environment, rather than different feeding behaviors.
Last, I investigated different nursery habitats for Goliath Groupers in southwestern Florida. I characterized juvenile nurseries based on the chemical fingerprints of trace elements within the inorganic matrix of the fin rays. Groupings based on these fingerprints were surprisingly accurate and can be used to identify essential nursery habitat for the species in years to come.
This research demonstrated the efficacy of novel techniques that were used to gather information on the life history of a critically endangered fish in the state of Florida. The results can be used to influence management strategies in the future, particularly with regard to nursery habitat use.
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Aging Juvenile Gulf Sturgeon From the Apalachicola River System, FloridaMoran, Kate Anne 25 May 2018 (has links)
No description available.
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