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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Delar av en grav och glimtar av en tid : om yngre romersk järnålder, Tuna i Badelunda i Västmanland och personen i grav X /

Fernstål, Lotta, January 2004 (has links)
Diss. Stockholm : Stockholms universitet, 2004.
32

High pressure processing of fresh tuna fish and its effects on shelf life

Zare, Zahra. January 1900 (has links)
Thesis (M.Sc.). / Title from title page of PDF (viewed 2008/01/30). Written for the Dept. of Food Science and Agricultural Chemistry, Macdonald College of McGill University. Includes bibliographical references.
33

Uncertainty in the management of activities affecting marine mammal populations : the tuna-dolphin conflict, a case study /

Alvarez-Flores, Carlos M., January 2002 (has links)
Thesis (Ph. D.)--University of Washington, 2002. / Vita. Includes bibliographical references (leaves 146-157).
34

Caracterización de semillas de diferentes accesiones de tunas (Opuntia ficus-indica (L.) Mill.), en relación a su ploidía y apomixis

Espinosa Henríquez, Franco Luciano January 2017 (has links)
Tesis presentada como parte de los requisitos para optar al Grado de Magíster en Ciencias Agropecuarias Mención en Producción Frutícola / La tuna es una de las especies de cactus más importante económicamente a nivel mundial, debido principalmente a la posibilidad de producirla en zonas áridas y semiáridas y los variados productos que se pueden obtener de ella. Esta es originaria del Golfo de México y el Caribe (CEZA, 2007) y desde allí se ha expandido por diversas partes del mundo. Esta especie fue introducida en España por los navegantes y desde allí se distribuyó por toda la cuenca del Mediterráneo y el resto de los continentes (Kiesling, 2012). Actualmente se encuentra en forma silvestre o cultivada en el sur de España, Francia, Grecia, Italia, Turquía, Israel y Sudáfrica, extendiéndose también dentro del mismo continente Americano desde Canadá hasta Chile (Sáenz, 2006).
35

Manejo del tamaño de fruto y la calidad de la tuna (Opuntia ficus indica, M.) mediante la regulación de la carga frutal, bajo condiciones de zona mediterranea y tropical / Management of fruit size and qualityof cactus pear (Opuntia ficus-indica, M.) trough the adjustment of the fruit load under conditions of mediterranean and tropical zone

Celi Soto, Adriana del Carmen January 2013 (has links)
Tesis presentada para optar al Grado de Magíster en Ciencias Agropecuarias, con mención en Producción Frutícola / La tuna (Opuntia ficus-indica) esta extensamente distribuida en México, gran parte de América Latina, África del Sur y a zona del Mediterráneo (Hassan et al., 2011).A nivel mundial son numerosos los países que producen tuna, siendo el mayor productor mundial, México (Según SAGARPA, 2010, citado por Sanhueza, 2010). Después de México otros países que producen tuna son Italia, Sudáfrica, Argentina, Chile, Bolivia, Perú, Colombia, Estados Unidos, Marruecos, Argelia, Libia, Tunes, Egipto, Jordania, Pakistán, Israel, Grecia, España y Portugal (Flores et al., 1995). Los principales mercados para este producto son Alemania, Francia, Holanda, Inglaterra, Estados Unidos y Japón (FAO, 2006).Chile es uno de los países productores de tuna cuya superficie plantada se centra en la Región Metropolitana con 611,4 ha de acuerdo al Catastro Frutícola (2010), mientras se encuentra en menores superficies entre las Regiones de Atacama y el Bio-Bio, siendo la superficie total de 1240.1 ha. California y México, se convierten en los principales proveedores del mercado de Estados Unidos, mercado al cuál las exportaciones Chilenas registran algunos picos durante los meses de septiembre a mayo. Mientras que Colombia exporta tuna a los mercados europeos durante todo el año (FAO, 2006).
36

Tunas brandgravar : stensättningar och individer i förändring / The cremation graves of Tuna : stone settings and individuals in change

Johansson, Evelina January 2011 (has links)
The Iron Age cemetery at Tuna in Badelunda parish, Västmanland, is a complex and unique burial ground used for only 69 graves during a period of roughly 700 years, between 300 - 1050 AC. The individuals buried at Tuna show an impressive variety of gravegods as well as stonesettings formed above the grave. Who where these people that were cremated at Tuna, among the mysterious women in the boats and the rich women in grave X? As we study the graves of the cremated individuals we reach a new understanding of the cemetery; from its social structure down to every individual. Through the analysis of the stonesettings, gravegods and bones we see a how these subjects, when analysed, show a picture of the individuals and social structure of the cemetery. It was a cemetery for the higher society and unique individuals rather then the average people.
37

The biology, ecology and exploitation of longtail tuna, Thunnus tonggol (Bleeker) in Oceania

Wilson, M. A (Marc A.) January 1982 (has links)
"June 1981" / Thesis (M.Sc.)--Macquarie University, School of Biological Sciences, 1982. / Bibliography: leaves 176-185. / This study was undertaken at the behest of the Papua New Guinea Government in 1973 and extended to 1978. It aimed at elucidating the various aspects of the life history of longtail tuna Thunnus tonggol with a consideration of the factors influencing distribution, relative abundance and exploitation. During this period, 414 tagged fish were released with an overall recapture rate of 8.6% being recorded. Age at first maturity was established at approximately 60 cm for both sexes with a spring-summer spawning being postulated on the basis of gonadal development as evidenced by increasing gonadal indices. No significant departure from the 1:1 sex ratio was observed. -- Von Bertalanffy growth eguations were derived from the reading of increments on sagittal otoliths and modal progression analysis, and yielded respectively:- Lt = 131.8 [1-e⁻·³⁹⁵ ⁽t⁻·⁰³⁵⁾] and Lt = 122.91 [1-e⁻·⁴¹ ⁽t⁻·⁰³²⁾] Both curves were consistent with growth indications from tag recoveries. The predictive length-weight relationship was determined to be ln(Wt) = -9.67+2.656 ln(L.C.F.) and no significant differences existed between the sexes. -- Longtail were shown to be opportunistic feeders: fish constituted the major portion of the diet and increased in accord with longtail size. It is postulated that longtail undergo longshore migrations due to thermal requirements and that these allowed for a hypothetical spawning site around the Aru Island region - an acknowledged nutrient rich area during spring. Both morphometric and biochemical analyses failed to establish the existence of an eastern and western Australian longtail tuna population although there is strong evidence to suggest that sub-specific differences occur between Malaysian and Australian-P.N.G. stocks. -- The exploitation of longtail at three levels; artisanal, amateur and commercial are reported. Concern is expressed as to the lack of data collection and collation of the Taiwanese gillnet fleet operating in the Australian Fishing Zone and about the exploitation of pre-adult longtail tuna. Accordingly, recommendations are made to alleviate the statistical problems and that consideration be given to a detailed study of the fishing parameters which affect the population dynamics of longtail tuna. The latter recommendation in particular should examine the impact that the foreign operated fishery has had on the stocks in Oceania. / Mode of access: World Wide Web. / ix, 195 leaves ill., maps
38

Electrolyzed oxidizing water treatment as a post-harvest process for controlling histamine formation in fish /

Phuvasate, Sureerat. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2008. / Printout. Includes bibliographical references (leaves 78-86). Also available on the World Wide Web.
39

Molecular systematics and population genetics of marine vertebrates from Brazil

Furtado-Neto, Manuel Antonio de Andrade, January 1998 (has links) (PDF)
Thesis (Ph. D.)--Memorial University of Newfoundland, 1998. / Includes bibliographical references (leaves 158-188).
40

Population genomics analysis of yellowfin tuna Thunnus albacares off South Africa reveals need for a shifted management boundary

Mullins, Rachel Brenna January 2017 (has links)
Yellowfin tuna Thunnus albacares is a commercially and economically important fisheries species, which comprises the second largest component of South Africa’s catch of tuna and tuna-like species. Catches of the species off South Africa are treated as two discrete stocks by the two tuna Regional Fisheries Management Organisations (tRFMOs) under whose jurisdictions they fall. Individuals caught off the Western Cape, west of the boundary between the tRFMOs at 20°E, are included in assessment and management of the Atlantic Ocean yellowfin tuna stock by the International Commission for the Conservation of Atlantic Tunas (ICCAT), and those caught east of this boundary are assessed and managed as part of the Indian Ocean stock by the Indian Ocean Tuna Commission (IOTC). The boundary between these stocks is based on the confluence of the two oceans in this region and does not incorporate the population structure of species. For sustainable exploitation of fisheries resources, it is important that the definition of management stocks reflects species’ biological population structure; the fine-scale stock structure of yellowfin tuna off South Africa is therefore a research priority which this study aimed to address by means of population genomics analyses. Yellowfin tuna exhibit shallow genetic differentiation over wide geographic areas, and as such traditional population genetic approaches have limited power in resolving fishery significant population structure in the species. Herein, a population genomic approach was employed, specifically, genome-wide analysis of single nucleotide polymorphisms (SNPs) discovered using a next-generation DNA sequencing approach, to confer (i) increased statistical power to detect neutral structuring reflecting population connectivity patterns and (ii) signatures of local adaptation. The mitochondrial Control Region (mtDNA CR) was also sequenced to compare the resolving power of different approaches and to permit coalescent based analyses of the species evolutionary history in the region. Neutral SNP loci revealed significant structure within the dataset (Fst=0.0043; P<0.0001); partitioning of this differentiation within the dataset indicated significant differentiation between yellowfin tuna from the Western Cape and the Gulf of Guinea in the eastern Atlantic Ocean, with no significant differentiation between individuals from the Western Cape and Western Indian Ocean regions. This indicates two population units wherein there is a separation of the Gulf of Guinea from the remaining samples (Indian Ocean including Western Cape) that are largely derived from a single genetic population. This pattern was also supported by assignment tests. Positive outlier SNPs, exhibiting signatures of diversifying selection, suggest that individuals from these regions may be locally adapted, as well as demographically isolated. The mtDNA CR did not reveal any significant genetic structure among samples (Fst=0.0030; P=0.309), demonstrating the increased resolving power provided by population genomics approaches, but revealed signatures of historical demographic fluctuations associated with glacial cycles. Based on the findings of this study, it is suggested that yellowfin tuna caught off the Western Cape of South Africa are migrants from the Indian Ocean population, exhibiting significant genetic differentiation from the Atlantic Ocean Gulf of Guinea individuals, and should thus be included in the assessment and management of the Indian Ocean stock. It is therefore recommended that the boundary between the Atlantic and Indian Ocean yellowfin tuna stocks, under the mandates of ICCAT and the IOTC respectively, should be shifted to approximately 13.35°E to include all individuals caught in South African waters in the Indian Ocean stock.

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