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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.
231

Fungal diversity from freshwater & riparian habitats and phylogeneticsof the Sordariales

Cai, Lei, 蔡磊 January 2006 (has links)
published_or_final_version / abstract / Ecology and Biodiversity / Doctoral / Doctor of Philosophy
232

Morphological and genetic differentiation of two loliginid squids in Asia.

January 2008 (has links)
Sin, Yung Wa. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 105-112). / Abstracts in English and Chinese. / Abstract --- p.i / Abstract (in Chinese) --- p.iii / Acknowledgements --- p.v / Contents --- p.vi / List of tables --- p.x / List of figures --- p.xii / Chapter Chapter 1 --- General introduction / Chapter 1.1 --- Introduction to loliginid squids --- p.1 / Chapter 1.1.1 --- Cephalopod taxonomy and fishery --- p.1 / Chapter 1.1.2 --- Family Loliginidae --- p.2 / Chapter 1.1.3 --- Genus Uroteuthis --- p.4 / Chapter 1.1.4 --- Uroteuthis chinensis and Uroteuthis edulis --- p.5 / Chapter 1.2 --- Introduction to morphological differentiation methods in cephalopods --- p.11 / Chapter 1.3 --- Introduction to genetic differentiation methods --- p.13 / Chapter 1.3.1 --- Molecular markers --- p.13 / Chapter 1.3.1.1 --- Animal mitochondrial DNA --- p.13 / Chapter 1.3.1.2 --- Microsatellite DNA --- p.14 / Chapter 1.3.2 --- Systematic studies of cephalopods using molecular markers --- p.15 / Chapter 1.3.3 --- Population genetic studies of cephalopods using molecular markers --- p.18 / Chapter 1.4 --- Objectives --- p.19 / Chapter Chapter 2 --- Morphological differentiation of Uroteuthis chinensis and Uroteuthis edulis --- p.20 / Chapter 2.1 --- Introduction --- p.20 / Chapter 2.2 --- Materials and methods --- p.21 / Chapter 2.2.1 --- Specimens --- p.21 / Chapter 2.2.2 --- Morphometric characters --- p.22 / Chapter 2.2.3 --- Multivariate analysis of data --- p.23 / Chapter 2.3 --- Results --- p.24 / Chapter 2.4 --- Discussion --- p.54 / Chapter Chapter 3 --- Genetic differentiation of Uroteuthis chinensis and Uroteuthis edulis --- p.57 / Chapter 3.1 --- Introduction --- p.57 / Chapter 3.2 --- Materials and methods --- p.58 / Chapter 3.2.1 --- Collection of specimens --- p.58 / Chapter 3.2.2 --- "DNA extraction, PCR amplification and sequencing" --- p.59 / Chapter 3.2.3 --- Sequence data analysis --- p.60 / Chapter 3.3 --- Results --- p.62 / Chapter 3.3.1 --- Sequence data set --- p.62 / Chapter 3.3.2 --- Phylogenetic analysis --- p.63 / Chapter 3.3.3 --- Sequence divergence within species --- p.67 / Chapter 3.4 --- Discussion --- p.89 / Chapter 3.4.1 --- Genetic differentiation of U. chinensis and U edulis --- p.89 / Chapter 3.4.2 --- Population structuring within U. chinensis and U edulis --- p.91 / Chapter Chapter 4 --- Isolation of microsatellite loci for U. chinensis --- p.94 / Chapter 4.1 --- Introduction --- p.94 / Chapter 4.2 --- Materials and methods --- p.95 / Chapter 4.3 --- Results --- p.97 / Chapter 4.4 --- Discussion --- p.102 / Chapter Chapter 5 --- Conclusion --- p.103 / References --- p.105 / Appendix 1: Aligned COI sequences used in this study --- p.113 / Appendix 2: Aligned 16S rRNA sequences used in this study --- p.122
233

Development of morphological forms in four-year-old children

Thompson, Catherine Anderson 01 January 1989 (has links)
The purpose of this study was to investigate morphological development in 4-year-old children. Two tests were utilized and compared to see if there was a significant difference between the expression of meaningful and nonmeaningful words. The first test, a modified version of the Test for Examining Expressive Morphology (TEEM), used meaningful words to assess allomorphic variations of six bound morphemes. The second test, a modified version of Berko's Test of English Morphology (BTEM), assessed the same allomorphic variations, but it used nonmeaningful words.
234

Relationships between leaf traits and herbivorous insect assemblages in a temperate Australian forest

Peeters, Paula J. (Paula Jane), 1969- January 2001 (has links)
Abstract not available
235

Functional Morphology of Gastropods and Bivalves

Sälgeback, Jenny January 2006 (has links)
<p>Functional morphology analyzes the relationships between form and function in organisms. However, a comprehensive analysis of any organic structure requires an integrated approach to morphology. For this purpose constructional morphology was developed, where function, phylogeny and construction together explain form. This thesis investigates functional and constructional aspects of gastropods and bivalves; two groups of molluscs which are among the most common shell-bearing invertebrates. Their shell protects the soft parts and different morphologic specializations enhance this function. Morphology and mode of life are often closely coupled. </p><p>Comparison of the distantly related cardiid bivalves <i>Cardium</i> <i>costatum</i> and <i>Budmania</i> spp. reveals similar shell modifications. Both have prominent keels functional in anchoring the shell within the sediment. The straight keels in <i>C. costatum</i> indicate an additional strengthening function, whereas the keels in <i>Budmania</i> spp. often are deformed and do not. Other shell modifications include secondary resorption of shell material and hollow keel interiors, reducing shell weight. These similarities are explained by parallel evolution and a common cardiid <i>Bauplan</i>.</p><p>Morphological shell characters in cerithiform gastropods have evolved independently in different taxonomic groups and multiple times within the same group. Shell characters are adaptive within five functional areas: defence from shell-peeling predators, burrowing and infaunal life, clamping, stabilization, and righting of the shell. Most characters are made feasible by determinate growth and a count-down programme.</p><p>In most environments predators that crush, peel and bore shells are present. As bivalves and gastropods grow by marginal accretion, and are able to replace lost shell material, traces of unsuccessful predation are preserved as scars. Experiments on the snail <i>Nucella lamellosa</i> show that repaired shells are just as strong as shells without damage. However, new scars follow old scar lines in 43% of tested specimens. This might be due to a higher organic content in this area.</p>
236

New insight into the morphology and physiology of Mesozoic archosaurs

Jones, Terry D. 05 May 2000 (has links)
Inferences regarding the biology of extinct taxa are often founded primarily on cladistically-based phylogenetic hypotheses. However, these inferences are frequently inconsistent with the morphology and physiology of modern animals. I suggest that reference to the biology of modern animals might be a more appropriate tool to aid in the reconstruction of the morphology and physiology of extinct animals. Here, this methodology is applied to: (1) reconstruction of the respiratory anatomy and physiology of some Paleozoic archosaurs (dinosaurs, early birds, pterosaurs, and early crocodilians), (2) understanding cursorial locomotion in birds and bipedal dinosaurs, and (3) a reinterpretation of an enigmatic archosaur, Longisquama. The conclusions drawn from these data raise questions regarding current thinking regarding relationships between birds and dinosaurs. / Graduation date: 2000
237

Functional Morphology of Gastropods and Bivalves

Sälgeback, Jenny January 2006 (has links)
Functional morphology analyzes the relationships between form and function in organisms. However, a comprehensive analysis of any organic structure requires an integrated approach to morphology. For this purpose constructional morphology was developed, where function, phylogeny and construction together explain form. This thesis investigates functional and constructional aspects of gastropods and bivalves; two groups of molluscs which are among the most common shell-bearing invertebrates. Their shell protects the soft parts and different morphologic specializations enhance this function. Morphology and mode of life are often closely coupled. Comparison of the distantly related cardiid bivalves Cardium costatum and Budmania spp. reveals similar shell modifications. Both have prominent keels functional in anchoring the shell within the sediment. The straight keels in C. costatum indicate an additional strengthening function, whereas the keels in Budmania spp. often are deformed and do not. Other shell modifications include secondary resorption of shell material and hollow keel interiors, reducing shell weight. These similarities are explained by parallel evolution and a common cardiid Bauplan. Morphological shell characters in cerithiform gastropods have evolved independently in different taxonomic groups and multiple times within the same group. Shell characters are adaptive within five functional areas: defence from shell-peeling predators, burrowing and infaunal life, clamping, stabilization, and righting of the shell. Most characters are made feasible by determinate growth and a count-down programme. In most environments predators that crush, peel and bore shells are present. As bivalves and gastropods grow by marginal accretion, and are able to replace lost shell material, traces of unsuccessful predation are preserved as scars. Experiments on the snail Nucella lamellosa show that repaired shells are just as strong as shells without damage. However, new scars follow old scar lines in 43% of tested specimens. This might be due to a higher organic content in this area.
238

Aspects of the reproductive biology of Argulus japonicus and the morphology of Argulus coregoni from Malaysia

Everts, Lourelle Alicia Martins 30 June 2011 (has links)
M.Sc. / A general introduction provides the foremost morphological characteristics of the genus. A breeding colony of Argulus japonicus was kept under laboratory conditions in order to study sperm transfer. Pairs in copula were studied with histology and scanning electron microscopy. Sections of copulating pairs revealed sperm on the accessory copulatory structures of the male; and scanning electron microscopy showed that sperm transfer occurs in three phases which can be differentiated to ten different stages. Sperm transfer occurs via a spermatophore in A. japonicus. This is the first observation of a spermatophore in Argulus. For the second part of this study, seven specimens of an unknown freshwater ectoparasitic crustacean were collected from red tilapia fish, kept for consumption at the “Langat Fishing, Seafood and Beer Garden” Restaurant just off the Langat River in Selangor, Malaysia. Initial investigation showed that the specimens were of the genus Argulus. Light and scanning electron microscopical studies were subsequently used to identify the species. A comparison with all Argulus species formerly described from Asia and the surrounding islands was conducted. The species was identified as Argulus coregoni, due to the presence of the roughly triangular shaped anterior respiratory areas and the kidney bean shaped posterior respiratory areas. Additionally, the abdomen with sharply pointed terminal ends as well as the presence of characteristic accessory protrusions on the second ii swimming leg of the male specimens confirmed this identification. This species has not previously been described from Malaysia. The final chapter of this dissertation contains an overall summative discussion of the different parts of this study and highlights future possible research avenues.
239

Aspekte van die genetiese samestelling en groei van Clarias gariepinus

Grobler, Johannes Paulus 13 February 2014 (has links)
M.Sc. / Please refer to full text to view abstract
240

Variation and Variability of Skull Morphology in Rodents (Mammalia: Rodentia) / 齧歯類頭骨形態の変異と可変性(哺乳綱:齧歯目)

Jadab, Kumar BISWAS 23 March 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第22279号 / 理博第4593号 / 新制||理||1659(附属図書館) / 京都大学大学院理学研究科生物科学専攻 / (主査)教授 本川 雅治, 准教授 中野 隆文, 教授 曽田 貞滋 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM

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