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Genetic and morphometric variation of Octopus vulgaris in the Benguela Current regionDe Beer, Chénelle Lesley January 2014 (has links)
The Benguela Current is a cold eastern boundary current located on the south-western coast of the African continent. The establishment of its present day features approximately two million years ago has triggered allopatric events which have driven genetic and/or phenotypic differentiation in many of the warm-temperate organisms that previously had continuous distributions along the south and west coast of southern Africa. However, since many of these species have responded differently, despite similar isolation times, research in this region provides a unique opportunity to increase our understanding of evolutionary processes. The common octopus (Octopus vulgaris, Cuvier 1797) is a coastal, sedentary species, inhabiting coral reefs or rocky environments at depths of up to a 100m. It is considered to be one of the most extensively studied cephalopod species due to its worldwide distribution. However, very little research has been conducted on O. vulgaris in southern Africa. In order to gain a holistic understanding of the effects of the Benguela Current on population connectivity, genetic and phenotypic diversity, and evolutionary history of O. vulgaris, a comparative genetic and morphological study was conducted across the Benguela region. A total of 168 specimens of O. vulgaris were collected from four different regions across the Benguela system. A small tissue sample was preserved in ethanol for molecular analysis, and the specimen was frozen whole for morphometric analysis in the laboratory. Octopus vulgaris genetic population structure and evolutionary history was investigated using a 580bp fragment of the mitochondrial cytochrome b (cytb) gene for 76 individuals located within the Benguela region, yielding 10 different haplotypes. AMOVA and pairwise FST analyses revealed significant genetic differentiation suggesting a northern-southern Benguela divergence. Estimates of time since most recent common ancestor, based on biogeographical calibrators and coalescent analyses, indicated that isolation between the Angolan and South African population occurred between ~231 Ka and 1 Ma. Mismatch distribution analyses revealed a past population expansion within the South African O. vulgaris roughly 129.31 Ka, whilst Bayesian skyline plots were indicative of gradual demographic growth within the Angolan population in the last ~100 Ka. Observed O. vulgaris population structure and demographic history was likely the result of historical climate-induced change within the system. Reconstruction of phylogenetic relationships within the Octopus genus, using cytb and COI suggest that O. vulgaris is not a monophyletic group and a major systematic revision is required. Furthermore, unidentified individuals from South Africa were found to group with species from Indo-West Pacific Oceans and were therefore considered to have been translocated through ballast water from Asia. While the molecular analysis indicated a significant northern-southern Benguela structure results from the principle component analysis (PCA) and discriminate function analysis (DFA) were unable to distinguish between O. vulgaris from different sampling localities throughout the Benguela Current region based on soft-parts, hard-parts and meristic characters. The lack of phenotypic variation, despite significant genetic divergence, highlights the importance of multi-method approaches in gaining a holistic understanding of the taxonomy and biogeography of species.
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A development and management framework for a new Octopus vulgaris fishery in South AfricaOosthuizen, Ané January 2004 (has links)
A new policy incorporating an operational protocol was developed for the establishment of new fisheries in South Africa. The common octopus, Octopus vulgaris was used as a candidate species for the project. The operational protocol consisted of a three-phased development framework, namely information gathering (Phase 0), an experimental fishery (Phase 1) and the final implementation of a commercial fishery (Phase 2). The present study focussed on phase 0 of this theoretical framework and protocol and was implemented by using a proposed octopus pot fishery in South Africa as a case study. Phase 0 included a desktop study, information gathering in the field, an economic feasibility study and the formulation of a Fishery Management Plan and experimental design for the fishery. Information gaps identified during the desktop study were addressed during field investigations into the population structure and biology of O. vulgaris along the southeast coast. Immature females were found to use the intertidal area to feed and grow before migrating to the subtidal area to mature and spawn. Mean size differed substantially between intertidal and subtidal areas, with larger octopus found subtidally. Age and growth trials using tetracycline as a marker showed that O. vulgaris deposit daily growth lines in their beaks. A genetic study showed that there is most likely only one panmitic population along the coast. The economic feasibility study indicated that a longline pot fishery could be feasible provided a 30% catch in 6600 pots/month is attained. Only existing, debt-free vessels should be used in this fishery. The Fishery Management Plan proposed in this study includes management measures such as effort limitation of licences and gear, size restrictions, vessel monitoring systems, and observer programmes. Based on the population dynamics and biology of O. vulgaris it is suggested that a precautionary approach to developing fisheries for this species in both the inter- and subtidal areas along the South African coast.
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Perspectives on the Historio-sociological Novel : Frank Norris' The OctopusO'Shea, Timothy Thomas 05 1900 (has links)
As an historio-sociological novel The Octopus is important because it synthesizes several features of late nineteenth century America, especially naturalism and the political preponderance of the Southern Pacific railroad. An analysis of this novel provides a better understanding of its features and adds a dimension to the perspective of history.
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Geomorphometric study of Octopus and Cistopus (Cephalopoda: Octopodidae) based on landmarks of beaksHsu, Chia-Chin 21 April 2003 (has links)
Traditional morphometric method measures the linear distance between two points on the body surface. Statistical techniques, mainly covariance analysis and principle component analysis, are respectively used in single- and multi- variable statistical inferences. Their purpose is to overcome the bias due to allometric growth. Geomorphometric methods (mainly superimposition method) studied the size and shape of organisms was developed at recent decade. These methods not only measure and analyze body shape and size directly, but are immune to the disturbance of allometric growth. They also enable scientists to study organic structure on a three dimensional space.
In this study, coordinates of landmarks on beaks surface were recorded to give information of shape as well as caliper distances. Superimposition method (Procrustes residuals) was applied to examine the difference between sexes, local populations and among different species of octopus. And the phenograms based on caliper distance and superimposition method were compared with the hypothesis of Norman and Sweeney on Octopus phylogeny.
Samples of all 11 species of octopus, belonging to genus Cistopus and three species-group of genus Octopus were collected around the water of Taiwan. No significant differences on landmark shape between sexes of O. aegina and of O. marginatus were found through principal component analysis. Samples of O. marginatus from Tungkang and Dahsi could be discriminated through the first principal component. The result does not match with that from DNA sequence analysis already reported. Such conflicts were considered the result of environmental effects. Canonical discrimination method was used for two types of data, namely Procrustes residuals and caliper distances. All species were significantly different from each other. A discriminate function based on Procrustes residuals data reclassified 92.7% of the specimens correctly, incomparing to the 86.1% based on caliper distances. Phenogram constructed from a matrix of Mahalanobis distance (D2) also showed different result. It was concluded that: 1) Result of geomorphometric analysis based on landmark data is not compatible with the hypothesis of Norman and Sweeny. 2) Beak characters based on caliper distance are suitable for discrimination between genera or species-groups, and support the separation of O. luteus from O. minor and O. sp. TW35.
Our study suggests that, either traditional morphometric method or the new geomorphometric method is a better tool for showing environmental effects than for phylognetic studies.
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Influence of variable environmental on population structure and reproductive biology focused on spermatophores of Octopus insularis / InfluÃncia de variÃveis ambientais na estrutura populacional e a biologia reprodutiva focada nos espermatÃforos do polvo, Octopus insularisBruno Braulino Batista 28 January 2016 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Octopus, are marine organisms belonging to the Filo Mollusca and are distributed around the world and are important to the marine ecosystem acting as opportunists and predators of great economic importance because it is part of several fishing. Although not yet know the extent to which these animals are able to withstand fishing pressure. In regard reproduction these organisms are dioecious with only playback (semelpareous), with high fertility with copulations. The paralavaes of O. insularis are planktonic, giving the species a high dispersal capacity. However, reproductive biology studies of O. insularis are still scarce, being restricted primarily to females and reproductive tract structures and size that these animals reach maturity. There is an absence of any information about the complex structure responsible for the fertilization of the oocytes in the case, the spermatophores. This work aims to analyze the influence of environmental variables in the population structure and reproductive biology focused on the spermatophores octopus, Octopus insularis. For this, we need to analyze the parameters of population biology, describe the spermatophore and describe the spermatophoric reaction. This thesis is divided in three chapters that discuss: 1) Population structure of Octopus insularis caught using longline pots related with environmental variables that had a significant body size variations in the rainy season, possibly related to the breeding period and was observed synchronism between the environmental variables and the life cycle of these animals. 2) Morphological description and functional anatomy from spermatophore of the Octopus insularis, which is divided into two structures sperm mass on aboral region being covered by the outer and middle layer and the ejaculatory apparatus that is separated by the granular liquid and the apparatus is covered by domestic and inner membrane coat, protecting the spiral filament. 3) Spermatophoric reaction in vitro octopus, Octopus insularis which lasts about 15 minutes starts with the outgrowth of ejaculatory apparatus and consequent release of sperm mass in the middle. / Polvos, sÃo organismos marinhos pertencentes ao Filo Mollusca e estÃo distribuÃdos ao redor do mundo, sendo importantes para o ecossistema marinho atuando como predadores oportunistas e de grande importÃncia econÃmica, pois faz parte de diversas pescaria. Embora, ainda nÃo se saiba atà que ponto estes animais consigam resistir à pressÃo da pesca. Com relaÃÃo a reproduÃÃo esses organismos sÃo diÃicos com reproduÃÃo Ãnica (semelparidade), apresentando alta fecundidade com cÃpulas. As paralarvas de Octopus insularis sÃo planctÃnicas, dando ao O. insularis uma alta capacidade de dispersÃo. PorÃm, estudos de biologia reprodutiva do O. insularis ainda sÃo escassos, sendo restrito basicamente a fÃmeas e as estruturas do aparelho reprodutivo e ao tamanho que esses animais atingem a maturaÃÃo e nÃo existindo nenhuma informaÃÃo sobre a complexa estrutura responsÃvel pela fertilizaÃÃo dos ovÃcitos, no caso, os espermatÃforos Esse trabalho tem como objetivo analisar a influÃncia de variÃveis ambientais na estrutura populacional e a biologia reprodutiva focada nos espermatÃforos do polvo, Octopus insularis. Para isto, serà necessÃrio analisar os parÃmetros da biologia populacional, descrever o espermatÃforo e descrever a reaÃÃo espermatofÃrica. Esta tese està dividida em trÃs capÃtulos que abordam a 1) A estrutura populacional do polvo, Octopus insularis capturado com espinhel de potes relacionado com variÃveis ambientais, que apresentou variaÃÃes de tamanho corporal significativa no perÃodo chuvoso, possivelmente relacionada ao perÃodo de reproduÃÃo e foi observado um sincronismo entre a variÃveis ambientais e o ciclo de vida destes animais. 2) A descriÃÃo morfolÃgica e anatomia funcional do espermatÃforo do polvo, Octopus insularis, que à dividido em duas estruturas a massa espermÃtica na regiÃo aboral sendo coberta pela tÃnica externa e mÃdia e o aparato ejaculatÃrio que à separado pelo liquido granular e o aparato à recoberto pela tÃnica interna e membrana interna, protegendo o filamento espiral. 3) A reaÃÃo espermatofÃrica in vitro do polvo, Octopus insularis que dura cerca de 15 minutos à iniciada com a evaginaÃÃo do aparato ejaculatÃrio e consequente lanÃamento da massa espermÃtica no meio.
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Central and Peripheral Visual Fields in Patients with MigraineEshtayah, Hadil 18 July 2012 (has links)
Purpose: To determine if patients with migraine show clinically apparent visual field deficits in the peripheral visual field compared to healthy controls.
Methods: Normal observers (n=25; mean age 41 y, range 15-67 y) and patients with migraine (n=12, mean age 48 y, range 21-55 y) were examined with a fully automated kinetic perimetry program (Octopus 900, Haag-Streit, Switzerland) on two separate study visits within two weeks. The program examined 3 isopters (I4e, I2e, I1e) at stimulus velocities of 5°, 4°, and 3°/s respectively. For every isopter, 12 stimulus vectors were presented at meridians spaced 30° apart, in random order, and each isopter was measured 3 times. Patients with migraine had been diagnosed by a neuro-opthalmologist according to criteria of the International Headache Society.
Results: Differences in mean isopter radius between migraine observers and healthy controls were small (< 1.3°) and not statistically significant (P>0.05, Mann-Whitney U). No learning or practice effects were observed between study visits, and AKP showed reasonable repeatability for all three isopters.
Conclusion: Patients with migraine did not demonstrate decreased peripheral visual fields in comparison to controls. This study had sufficient power (90%) to detect a group difference in mean isopter radius of approximately 2°.
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CDNA cloning and sequencing of Octopus dofleini hemocyanin /Lang, Walter H. January 1990 (has links)
Thesis (Ph. D.)--Oregon State University, 1991. / Includes mounted photographs. Typescript (photocopy). Includes bibliographical references (leaves 112-119). Also available on the World Wide Web.
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Diseño y optimización de un pienso extrusionado para la alimentación y crecimiento del pulpo común (Octopus vulgaris)Querol Ordóñez, Pablo 14 July 2014 (has links)
Durante la presente investigación, se formularán y fabricarán diferentes piensos extrusionados conteniendo diferentes aglutinantes y atrayentes con objetivo de que lo acepten e ingieran los pulpos. Posteriormente se trabajará en la mejora de las condiciones físicas de los piensos, como la dureza y la elasticidad, además de la composición nutricional, con el fin de mejorar, tanto la ingesta como el crecimiento de los pulpos. / Querol Ordóñez, P. (2014). Diseño y optimización de un pienso extrusionado para la alimentación y crecimiento del pulpo común (Octopus vulgaris) [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/38758 / TESIS
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EFFECTS OF COMBINING A WEARABLE VISUAL SCHEDULE AND A CLASS-WIDE TOKEN ECONOMY ON SELF-INITIATED TRANSITIONSVargas, Karynna 01 August 2022 (has links)
TITLE: EFFECTS OF COMBINING A WEARABLE VISUAL SCHEDULE AND A CLASS-WIDE TOKEN ECONOMY ON SELF-INITIATED TRANSITIONSMAJOR PROFESSOR: Dr. Natalie F. Williams AwodehaProblem behaviors in young children are associated with long-term academic and social struggles. Moreover, the prevalence is expected to increase with the implications of the coronavirus pandemic of 2019 (COVID-19). As a result, implementing positive behavior techniques early on will reduce the likelihood of problem behavior. A [BL] [ X] [Y] [BL] [XY] component analysis was used to study the individual components: Visual activity schedules (VAS), ClassDojo®, and the results of combining interventions on self-initiated transitions in a bilingual preschool classroom. Participants were 4 to 5 years old, in a general education who displayed difficulty transitioning. First, the study observed participants transitioning without added assistance. After, participants were to wear an Octopus watch® and then participate in a class token economy with recorded self-initiated transitions. A return to baseline followed, and lastly, a combined VAS and ClassDojo® intervention was implemented to see its impact on transitions. The results found a socially significant improvement from baseline compared to combined components across all participants in the study. Results supported combining VAS with a token economy using effective reinforcers to improve self-initiated transitions among preschoolers in the public-school setting. However, future replications with limitations addressed in this study will be needed to back claims.
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OctaviaFarber, Michelle Ann 18 April 2019 (has links)
Octavia is a 3D animated story based on experiences of Army divers in the waters of Southeast Asia. I built a strong core set of skills in end-to-end 3D animation throughout my time in the graduate program, and I wanted to incorporate them into a real story for this thesis. The myriad of stories I grew up with inspired the development of this 3D animation due to their uniqueness and their nature as a verbal history.
This thesis is based on two objectives: technical excellence in the process of 3D animation, and sharing a previously verbal history to a larger audience. I achieved these goals using a variety of technical animation tools including ZBrush, Maya, Arnold, and Premier. Octavia itself is a modified story from my father's time diving in South Korea. The story details the interactions between an exceptionally curious octopus, Octavia, and a diver, taken from Octavia's perspective. The animation was well received during my defense for its technical difficulty and unique art styles. Octavia will be available online on my website. / Master of Fine Arts / Octavia is a 3D animated story based on experiences of Army divers in the waters of Southeast Asia. I built a strong core set of skills in end-to-end 3D animation throughout my time in the graduate program, and I wanted to incorporate them into a real story for this thesis. The myriad of stories I grew up with inspired the development of this 3D animation due to their uniqueness and their nature as a verbal history.
This thesis is based on two objectives: technical excellence in the process of 3D animation, and sharing a previously verbal history to a larger audience. I achieved these goals using a variety of technical animation tools including ZBrush, Maya, Arnold, and Premier.
Octavia itself is a modified story from my father’s time diving in South Korea. The story details the interactions between an exceptionally curious octopus, Octavia, and a diver, taken from Octavia’s perspective. The animation was well received during my defense for its technical difficulty and unique art styles. Octavia will be available online on my website.
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