Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 16 of 16 for “"Tunicate"”.
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Biologically active compounds from a clam and a tunicate
Part I. Isolation and characterization of sphingosine analogs from the clam Spisula polynyma. Extracts of the Stimpson surf clam, Spisula polynyma, were found to cause a distinct alteration of the morphology of L1210 murine leukemia cells in which the compounds develop sharp points, usually located …
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The porphynoid pigments of the Caribbean tunicate Trididemnum solidum
… a nickel chlorin isolated from the Caribbean tunicate Trididemnum solidum, has been identified as nickel (II) 2-devinyl-2-hydroxymethylpyropheophorbide a by chemical and spectroscopic methods. A partial synthesis of dimethyl tunichlorin from chlorophyll a (7 steps, 5% overall yield) has also …
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Polyandrocarpidines: Antimicrobial and Cytotoxic Compounds From the Marine Tunicate Polyandrocarpa Sp
The marine tunicate Polyandrocarpa sp. contains anti-microbial and cytotoxic metabolites, polyandrocarpidines, whose structures include a polymethylenediamine chain; one nitrogen is acylated with a twelve-carbon fatty acid which contains a cyclopropene ring in conjugation with a diene system, the …
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Marine Natural Products Chemistry of a Caribbean Tunicate and a Palau Sponge
Finally, new bromotyrosine-derived metabolites of the spirocyclohexadiene-isoxazoline class, named subereamides, have been isolated from the Palau sponge Suberea laboutei along with known psammaplysins A, B and D, and ceratinamide B. In addition, a new cytotoxic dibromotyramine derivative, …
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Genomic and physiological adaptation to temperature in the invasive golden star tunicate (Botryllus schlosseri)
… the range expansion of the invasive golden star tunicate, Botryllus schlosseri, as a natural experiment to study how a pernicious NIS adapts its thermal physiology on contemporary time scales. In Chapter 2, I applied low-coverage whole genome sequencing (lcWGS) to investigate patterns of …
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Biologically active compounds from tunicates and a sponge
… isolated from a relatively polar extract of the tunicate T. solidum. Their structures were determined by spectroscopic techniques and chemical degradations as follows: didemnins X ((R)-3-hydroxydecanoyl-(Gln)$\sb3$-Lac-Pro-didemnin A); Y ((R)-3-hydroxydecanoyl-(Gln)$\sb4$-Lac-Pro-didemnin A); M …
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Part I. The Acyl-Tunichlorins: A New Class of Nickel Chlorins Isolated From the Caribbean Tunicate Trididemnum Solidum. Part II. Cytotoxic Constituents of the Sponges Stylissa Carteri and Petrosia Sp. Part III. Electrospray Tandem Mass Spectrometry Studies
In addition we have explored the potential of ESI as an alternative to high energy tandem mass spectrometry methods in the structure elucidation of cyclic peptides and depsipeptides. Furthermore a new polyacetylene was identified in the marine sponge Petrosia sp.
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Total synthesis of N-(benzyloxycarbonyl)didemnin A
… a cyclic depsipeptide isolated from a Caribbean tunicate, was synthesized by coupling two key fragments, (Boc-(3S,4R,5S)-Ist(TBDMS)-(2R,S;4S)-Hip-Leu-Pro-OH (Fragment I)) and (Z- scD-MeLeu-Thr(H-Me$\sb2$Tyr)-OTMSe) (Fragment II). Fragment I was synthesized, in turn, from …
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New cytotoxic natural products from North-Eastern Pacific marine invertebrates
… an undescribed species of Aplidium, a compound tunicate found in the waters off the Queen Charlotte Islands. Langarin (142) was active in vitro againstL1210 murine leukemia cells with an ED50 of 0.44g/mL. Examination of extracts of the colonial tunicate Aplidium californicum resulted in the …
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Structures of the Didemnins (Antiviral, Antitumor, Compounds)
… have been isolated from a Caribbean tunicate. Their amino acid compositions were ascertained by gas chromatography/mass spectrometry of the trifluoroacetyl n-butyl ester derivatives of the amino acids present in the total acid hydrolyzates. The identities of non-amino acyl components …
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Climate change and invasive species interact to impact succession and diversity in Gulf of Maine marine fouling communities
… is predicted to decline; concurrently invasive tunicates (ascidians) became conspicuous members of fouling communities. These abiotic and biotic changes may lead to shifts in species composition, diversity and succession. The goals of these studies were to examine the relationship between …
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Study of Hybrid Cellulose Nanocrystals in Polymeric Nanocomposites
… of resources, including wood, bacteria, and tunicate which is a marine animal. In the past decades, academic and industrial communities have considered CNCs to develop biodegradable materials for a wide range of applications. The alignment and interaction between CNCs with different aspect …
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Genomic and physiological adaptation to temperature in the invasive golden star runicate (Botryllus schlosseri)
… the range expansion of the invasive golden star tunicate, Botryllus schlosseri, as a natural experiment to study how a pernicious NIS adapts its thermal physiology on contemporary time scales. In Chapter 2, I applied low-coverage whole genome sequencing (lcWGS) to investigate patterns of …
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CHARACTERIZATION OF THE EUKARYOTIC TRANSLATION INITIATION FACTOR 4E (eIF4E) FAMILY MEMBERS IN THE ZEBRAFISH (Danio rerio)
… available, as well as those of echinoderm, tunicate and cephalocordate, has allowed a glimpse of the origins and evolution of the eIF4E family in vertebrates. All deuterostomes have one representative from each class of eIF4Es. Early deuterostomes such as sea urchins, tunicates, and …
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Trophic role of small cetaceans and seals in Irish waters
… species, 14 cephalopods, four crustaceans, and a tunicate) were identified. 28% of the fish species were identified using bones other than otoliths, highlighting the importance of using all identifiable structures to reconstruct diet. Individually, each species of marine mammal presented a high …
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DEVELOPMENT OF THE LARVAL PERIPHERAL NERVOUS SYSTEM IN THE ASCIDIAN CIONA INTESTINALIS: ROLE OF THE RETINOIC ACID AND FGF/WNT SIGNALLING PATHWAYS AND OF THE POU TRANSCRIPTION FACTORS.
… of the larval peripheral nervous system of the Tunicate Ciona intestinalis with two main aims: a) to understand how the interactions between Retinoic Acid (RA) and the FGF/WNT pathways control its development; b) to study the role played by transcription factors of the POU family in its …