Thesis--Columbia University. / Bibliography: p. 98-100.

Thesis (M.S.)--Naval Postgraduate School, 1978. / Includes bibliographical references.

Thesis (Ph. D.)--University of Wisconsin, 1967. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Orientadora : Luiz Laureno Mafra Junior / Dissertação (mestrado) - Universidade Federal do Paraná, Setor de Ciências da Terra, Programa de Pós-Graduação em Sistemas Costeiros e Oceânicos. Defesa: Pontal do Paraná, 31/03/2014 / Inclui referências : f. 31-35;53-56 / Resumo: Pseudo-nitzschia é um gênero cosmopolita de diatomáceas penadas capazes de formar cadeias lineares de células sobrepostas, e de produzir o aminoácido neurotóxico ácido domóico (AD), normalmente sob situações de estresse, quando há diminuição no metabolismo primário da célula. Neste estudo, foi realizada uma busca por espécies potencialmente tóxicas de Pseudo-nitzschia em áreas próximas a parques de cultivo de bivalves nos estados do Paraná e Santa Catarina, com o intuito de se estabelecer o cultivo laboratorial a partir de cepas isoladas, avaliar a capacidade de produção e liberação de AD ao longo de suas curvas de crescimento, e medir as taxas alimentares e de acúmulo de toxinas em bivalves expostos aos cultivos. Amostras foram tomadas para quantificar o AD por cromatografia líquida com detecção ultravioleta (HPLC-UV). Foram isoladas 23 cepas entre 2011 e 2013, que se somaram a outras 4 previamente isoladas em 2003. As cepas PSN-11 (Pseudo-nitzschia calliantha) e PSN-4 (P. cf. multiseries) produziram baixos níveis de AD (máximo de 0,054 fg.cél.-1 e 0,152 pg.cél.-1, respectivamente). Um experimento com a cepa PSN-40 (P. calliantha) buscou testar o desencadeamento da produção de AD sob estresse luminoso (luz contínua) e agitação mecânica constante. Não foi detectada produção de toxina sob nenhum tratamento. Porém, a agitação promoveu a manutenção das células em longas cadeias por todo experimento, indicando que a turbulência altera a disponibilidade das células à ingestão por organismos planctívoros no ambiente natural. A resposta alimentar dos bivalves comerciais cultivados no sul do Brasil - as ostras Crassostrea gigas e C. brasiliana e o mexilhão Perna perna - frente a florações simuladas de Pseudo-nitzschia foi avaliada por meio de: (i) dois ensaios onde aos bivalves foi ofertada uma dieta exclusiva de Pseudo-nitzschia em câmaras de incubação, comparando as taxas de clareamento (TC, ml.min-1) em cada espécie; e (b) um experimento para se medir o acúmulo e a detoxificação de AD em ostras Crassostrea spp. e mexilhões P. perna expostos a uma dieta de P. multiseries tóxica por 23 h, seguido da depuração em dieta não tóxica (Isochrysis galbana) por 168 h. Mexilhões apresentaram TC's (4,1 ml.min-1) significativamente maiores do que as de C. gigas (1,7 ml.min-1) e C. brasiliana (1,4 ml.min-1). Entretanto, não acumularam AD em níveis detectáveis por HPLC-UV, sugerindo uma baixa assimilação e/ou alta taxa de detoxificação de AD em P. perna. Ostras Crassostrea spp. acumularam mais AD (máx. 4,85 ?g g-1), mas ainda abaixo do limite máximo permitido para comercialização (20 ?g AD g-1). Foi relatado no presente estudo uma baixa toxicidade das espécies de Pseudo-nitzschia spp. isoladas no sul do Brasil, e um baixo acúmulo com alta taxa de detoxificação de AD nas espécies de bivalves investigadas, porém o monitoramento contínuo do fitoplâncton e de toxinas deve ser mantido para se prevenir possíveis eventos de intoxicação durante florações mais tóxicas e/ou mais densas do que as condições testadas no presente estudo. Palavras chaves: toxicologia, ASP, maricultura, cultivo de bivalves, floração de algas nocivas, ácido domóico, Brasil / Abstract: Pseudo-nitzschia spp. are cosmopolite diatoms able to form stepped cell chains, capable of producing the neurotoxic amino acid domoic acid (DA), normally synthesized under stressing situations, when primary metabolism decreases. This study carried out an extensive search for potentially toxic Pseudo-nitzschia species near bivalves farms in the states of Paraná and Santa Catarina, in order to: (a) establish clonal cultures by isolating local cells; (b) evaluate the capacity for DA production and release throughout the growth curve; and (c) measure feeding rates and toxin accumulation in bivalves exposed to the cultures. Periodic samples were taken to quantify the DA concentrations by HPLC-UV. Twenty three strains were isolated between 2011 and 2013, besides 4 previously isolated in 2003. Strains named PSN-11 (Pseudo-nitzschia calliantha) and PSN-4 (P. multiseries) produced low DA levels (max. 0.054 fg.cell-1 and 0.152 pg.cell-1, respectively). Another experiment was designed to infer whether constant light and/or turbulence would boost DA production in PSN-40 (P. calliantha). No DA production was detected under any conditions tested. However, constant swirling sustained the long cell chains throughout the experiment, indicating that turbulence might affect the cell availability for planktivorous organisms in the field. The feeding responses of commercially raised bivalves in southern Brazil, the oysters Crassostrea gigas and C. brasiliana and the mussel Perna perna, exposed to simulated Pseudo-nitzschia blooms, were evaluated in: (i) short-term assays where bivalves were fed monoalgal Pseudo-nitzschia diets in incubation chambers, and the clearance rate (CR, ml.min-1) was compared; and (ii) long-term DA accumulation experiments, in which oysters Crassostrea spp. and brown mussels P. perna were exposed to a toxic P. multiseries diet for 23 h, followed by a 168-h depuration period on a non-toxic diet (Isochrysis galbana). Mussels exhibited significantly higher CR's (4.1 ± 0.39 ml min-1) than oysters C. gigas (1.7 ± 0.45 ml.min-1) and C. brasiliana (1.4 ± 0.39 ml.min-1), although no DA accumulation was detected by HPLC in the first, suggesting low toxin assimilation and/or rapid elimination. Crassostrea spp. accumulated higher DA levels (4.85 ?g.g-1), but they remained well below the regulatory limit of 20 ?g DA g-1. We reportedlow toxicity among the Pseudo-nitzschia spp. in southern Brazilian waters, as well as low DA accumulation and high detoxification rates for commercial bivalve species in this study, but continuous monitoring of plankton and toxins must be performed in order to detect prevent intoxications during blooms either more toxic and/or denser than the moderate conditions tested herein. Keywords: toxicology, ASP, aquaculture, bivalve farming, harmful algal blooms, domoic acid, Brazil.

"Cytogenetics and biology of selected representatives of the family Sphaeriidae" Mgr. ing. Tereza Kořínková Abstract of a PhD. thesis The thesis has a form of four separate articles, the full texts of which are included. Two of them were published, one was accepted and one was under revision before submission of the PhD thesis. The articles deal with cytogenetics, breeding and nutrition of selected representatives of the hermaphroditic, viviparous, primarily freshwater bivalves of the family Sphaeriidae (Mollusca: Bivalvia: Veneroida). Although various aspects of the biology of Sphaeriidae have been intensely studied for more than 100 years, many questions still remained unresolved. This thesis brings data on chromosome numbers of 11 species(10 of which have not been studied cytogenetically before) and information on the course of meiosis in two of these species (Chapter 1). Although the chromosome numbers are high (from ca. 140 to more than 240), the behaviour of chromosomes at meiosis rather corresponds to that of diploid organisms. Also the DNA contents in five selected species with high chromosome numbers (as measured by flow- cytometry) do not differ significantly from those in sphaeriids with a diploid chromosome number of 30. Such results contradict an origin of the high chromosome numbers by a...

Inúmeros pesticidas são usados na agricultura, para controle de pragas e ervas daninhas. Dentre eles destaca-se o herbicida atrazina, intensivamente utilizado nas culturas de cana-de-açúcar, milho e sorgo, que ocupam extensas áreas no estado de São Paulo. Grande parcela do herbicida, que é aplicado na agricultura, entra em contato com o solo, podendo ser lixiviado, atingindo as águas superficiais. Neste sentido, alguns animais como, por exemplo, moluscos bivalves, podem ser utilizados como monitores biológicos do ambiente aquático e auxiliar no estudo da ecotoxicologia. Considerando o risco de contaminação do ambiente aquático pela atrazina, propõe-se, no presente trabalho, desenvolver uma metodologia de análise daquele herbicida nos tecidos nas espécies de bivalves límnicos Anodontites trapesialis (LAMARCK, 1819) e Corbicula fluminea (Muller, 1789), validar esse método e, finalmente, verificar se ocorre a bioacumulação do herbicida nas partes moles dessas duas espécies. Como técnica de extração utilizou-se a extração líquido- líquido e como técnica de análise, a cromatografia líquida de alta eficiência (CLAE). / Large amount of pesticides have been used for the control of agriculture pests and weeds. Particularly important among herbicides is atrazine, extensively employed in cultures of sugar cane, corn and sorghum, that occupies an extensive area in São Paulo state. Large portions of atrazine, applied in the agricultural fields, leaches from the soil to surface water systems. In this way, some organisms such as fresh- water mollusks bivalves, can be used as biological monitors of aquatic environments, contributing for ecotoxicology studies. Considering the existence of risk of contamination by atrazine of the aquatic environment, the purpose of this work was, (i) to develop a method for the analysis of atrazine in the fresh- water bivalves species Anodontites trapesialis (LAMARCK, 1819) and Corbicula fluminea (MULLER, 1789), (ii) to validate such method and, (iii) to detect if these organisms can bioaccumulate atrazine in their tissues. This method involved a simple liquid-liquid extraction procedure, followed by high- performance liquid chromatographic analysis (HPLC).

From September 2009 to July 2011 I collected vertically stratified zooplankton samples and recorded estuarine water parameters on a monthly basis in the Coos Bay estuary, Oregon during flood and ebb tides. I identified five taxa of juvenile bivalves in the plankton:

El área estudiada comprende las regiones de Igualada, Manresa, Vic y Girona, desde la Conca de Barberà hasta la playa de Pals, en el Mediterráneo. De las subclases Paleotaxodonta y Pteriomorphia se han reconocido un total de 14 familias, 27 géneros (44 especies y 10 indeterminables específicamente). De ellas, 20 especies se citan por primera vez en esta área y 3 especies son endémicas. Frente a otros bivalvos, presentan casi siempre la concha.Las especies se hallan predominantemente en litologías detríticas finas y calcáreas. En su mayoría eran epifaúnicas y semiinfaúnicas. De las pocas infaúnicas, su modo de fijación era diverso. Predominantemente, habitaban la parte alta de la zona infralitoral, entre la marea baja y los 50 m de profundidad. Aguas con salinidad normal. Los géneros habitan actualmente en latitudes tropicales o templadas.En cuanto a la edad de las unidades que las contienen, la asociación de especies indica que es dificil discernir una edad luteciense o bartoniense, si bien las unidades inferiores contienen mayor número de especies lutecienses y las unidades superiores, especies bartonienses. La mayoría de los géneros tienen representantes actuales.La asociación de especies de dichas unidades inferiores muestra gran similitud con las del Luteciense de las cuencas del W europeo. La de las superiores con el Bartoniense de Aquitania y Biarritz. Ambas, con las del Priaboniense de Italia y Balcanes. / The area studied includes the regions of Igualada, Manresa, Vic and Girona, from the Conca de Barberà zone to the Pals beach, on the Mediterranean coast.14 families and 27 genera (44 species and 10 of undeterminable species) of the subclasses Paleotaxodonta and Pteriomorphia (bivalves) have been recognised. 20 of those species have been reported for the first time in this area and another 3 are endemic. Unlike other bivalves, the great majority of them keep the shell.The species are predominantly found in fine, calcareous detrital lithologies. Most of the species were epifaunal or semi-infaunal. The few infaunal species present in the area had diverse fixation systems. For the most part, they dwelled in the upper part of the infralittoral zone, between the low tide and 50 m deep, in waters of normal salinity. The genus dwell in tropical or temperate latitudes.As for the age of the units that contain them, the association of species shows that it is difficult to discern Lutetian or Bartonian age; although the presence of Lutetian species is higher in lower units, and the Bartonian species appear in a larger number in upper units. Most of the genuses have representation nowadays.The association of species found in the lower units shows a great similarity to those of the Lutetian of the west European basins. The one found in the upper units, bears resemblance to the Bartonian of Aquitanie and Biarritz. Both associations show similarities to those found in the Italian and Balkan Priabonian.

Reproduction de : Thèse de doctorat : Sciences et ingénierie des ressources procédés produits environnement. Discipline de la vie; Toxicologie de l'environnement : Metz : 2003. / Titre provenant de l'écran-titre. Notes bibliographiques.

Στην παρούσα διδακτορική διατριβή μελετήθηκε η βιολογία του είδους Ruditapes decussatus (Linnaeus, 1758) από τη λιμνοθάλασσα του Αράξου και το εκβολικό σύστημα του Ευήνου. Ο στόχος της μελέτης ήταν η βαθύτερη γνώση της βιολογίας του R. decussatus στα δύο ελληνικά οικοσυστήματα, η οποία δύναται να συμβάλει τόσο στην ορθολογική αλιευτική του διαχείριση, όσο και σε μια ενδεχόμενη συστηματική καλλιέργειά του στην Ελλάδα. Για το σκοπό αυτό πραγματοποιήθηκαν τυχαίες δειγματοληψίες σε δεκαπενθήμερη βάση επί τρία χρόνια. Τα αποτελέσματα έδειξαν ότι οι δύο πληθυσμοί διαφέρουν σε σημαντικό βαθμό σε ό,τι αφορά την αύξηση και τη θνησιμότητα, ενώ οι διαφορές στην αναπαραγωγική τους συμπεριφορά είναι μικρότερης έκτασης. Ειδικότερα ο πληθυσμός στη λιμνοθάλασσα του Αράξου εμφανίζει άριστα χαρακτηριστικά αύξησης και αναπαραγωγής, ενισχύοντας την άποψη ότι μια απόπειρα εντατικής καλλιέργειας του είδους στη χώρα μας θα στεφόταν με επιτυχία. Επίσης αποκομίστηκαν σημαντικά συμπεράσματα που αφορούν την ηθολογία του είδους και τη συμπεριφορά του σε καταστάσεις κινδύνου. / In the present doctoral thesis we studied the biology of two populations of the bivalve Ruditapes decussatus, one located in the lagoon of Araxos and the other in the estuary of Evinos River. The objective of the study was the use of the results in order to contribute in the species’ rational and successful management and in the development of an aquaculture industry in Greece. For this aim species were randomly sampled every two weeks in a three-year period. The results showed that the two populations differ significantly regarding increase and mortality, while the differences in their reproductive behaviour are less important. Specifically the population in the lagoon of Araxos shows excellent characteristics regarding increase and reproduction, supporting the opinion that an attempt of intensive culture of this species in our country would be crowned with success. Also we obtained important informations that concern the ethology of the species and its behavior in stress situations.