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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.
51

Revisão taxonômica do gênero Pseudophallus Herald 1940 com estudo osteológico de Pseudophallus brasiliensis Dawson 1974 (Teleostei, Syngnathiformes, Syngnathidae) / Taxonomic review of the genus Pseudophallus Herald 1940 with an osteological study of Pseudophallus brasiliensis Dawson 1974 (Teleostei, Syngnathiformes, Syngnathidae)

Gomes, Caio Isola Dallevo do Amaral 06 February 2017 (has links)
Este trabalho é dividido em uma revisão taxonômica do gênero Pseudophallus Herald 1940 e em um estudo osteológico de P. brasiliensis. Pseudophallus foi descrito a partir de duas espécies distribuídas nas drenagens costeiras do Oceano Pacífico no continente americano (P. starskii e P. elcapitanensis) e posteriormente foi incluída uma espécie das drenagens costeiras do Oceano Atlântico, P. mindii, com ocorrência registrada até recentemente entre o estado de São Paulo, Brasil até Belize na América Central, incluindo as ilhas do Caribe. Em 1974 foi descrita uma nova espécie, P. brasiliensis, com base em exemplares coletados no Rio Tocantins com contagens merísticas mais baixas do que os exemplares da América Central e do resto do território brasileiro. Além disso, os exemplares brasileiros apresentavam uma variação clinal decrescente em sentido Sul-Norte nas contagens merísticas. Em 1982 esta espécie foi sinonimizada com P. mindii pelo fato de outros exemplares coletados em localidades distintas apresentarem valores merísticos próximos aos dos exemplares coletados no Rio Tocantins, indicando que esses valores mais baixos eram resultado de variação intraespecífica ao longo da distribuição de P. mindii. A fim de investigar a variação intraespecífica em P. mindii foi proposta uma revisão taxonômica de P. mindii que acabou se desdobrando em uma revisão do gênero Pseudophallus. Foram analisados caracteres morfométricos e merísticos de 443 exemplares de todas as espécies de Pseudophallus, provenientes de todas suas distribuições nas drenagens do Atlântico e do Pacífico e incluindo material-tipo. Cinco espécies puderam ser reconhecidas: P. elcapitanensis e P. starksii nas drenagens costeiras do Oceano Pacífico, P. mindii e P. brasiliensis nas drenagens do Oceano Atlântico, revalidando P. brasiliensis, e uma espécie nova endêmica do Lago Izabal na Guatemala. Estas espécies são redefinidas e redescritas, com algumas considerações taxonômicas e biogeográficas. Na segunda parte deste trabalho, abordou-se de forma exploratória a osteologia de P. brasiliensis com intuito de se familiarizar com o esqueleto de Syngnathidae e abordar questões nomenclaturais de sua anatomia. A família Syngnathidae é representada por diferentes espécies de peixes cachimbo, cavalos marinhos e dragões marinhos, com um grande conjunto de características que tornam esse grupo facilmente identificável como o corpo coberto por anéis ósseos, maxilase dêntulas, ausência de nadadeiras pélvicas e ossos intermusculares, abertura opercular reduzida a um poro na membrana opercular e principalmente pelo fato dos machos carregarem os ovos fecundados em uma bolsa incubadora. Embora seja um grupo tão peculiar e distinto morfologicamente, estudos osteológicos são raros e focados principalmente nos cavalos marinhos (gênero Hippocampus) e não existem trabalhos filogenéticos com base em caracteres morfológicos. Neste estudo foi possível levantar informações acerca da osteologia de P. brasiliensis que permitiram comparar e discutir questões da morfologia deste grupo que foram debatidas ao longo dos anos em diferentes trabalhos disponíveis na literatura, como a questão da existência do metapterigóide, composição dos arcos branquiais e da cintura peitoral. A osteologia de P. brasiliensis foi estudada levando em consideração essas questões a fim de se criar uma base para futuros estudos anatômicos e filogenéticos do grupo / This work is divided in a taxonomic review of the genus Pseudophallus Herald 1940 and an osteological study of P. brasiliensis. Pseudophallus was described based on two species occurring on the coastal drainages of the Pacific Ocean in the new world (P. starskii and P. elcapitanensis) and later, an additional species from the coastal drainages of the Atlantic Ocean, P. mindii, with a distribution ranging until recently from the Brazilian state of São Paulo, to Belize in Central America, including the Caribbean islands. In 1974 a new species, P. brasiliensis, was described based on specimens collected in the Tocantins River with lower meristic counts than the Central American specimens and the ones from the rest of the Brazilian territory. Besides that, the Brazilian specimens presented a decreasing clinal variation in a South-to-North direction in some meristic counts. In 1982 this species was synonymized with P. mindii due to the fact that specimens collected in other localities presented meristic counts similar to those collected in the Tocantins River, indicating that these lower counts were due to an intraspecific variation along the distribution of P. mindii. In order to investigate this intraspecific variation in P. mindii, a taxonomic review was proposed which became a taxonomic review of the genus Pseudophallus. In total 443 specimens, including type material, of all the species of Pseudophallus from along their entire distribution on the Atlantic and Pacific drainages had their meristic and morphometric characters studied. Five species are recognized: P. elcapitanensis and P. starksii from the Pacific drainages, P. mindii and P. brasiliensis from the Atlantic drainages, revalidating P. brasiliensis, and a new species endemic of the Lake Izabal, in Guatemala. Those species were redefined and redescribed herein, with some comments on their taxonomy and biogeography. On the second part of this study, an exploratory study on the osteology of P. brasiliensis was conducted, with the purpose of getting familiar with the osteology of the Syngnathidae and to address nomenclatural questions of their anatomy. The Syngnathidae are represented by different species of pipefishes, seahorses and seadragons, with a great array of characteristics that make this group easily recognizable such as the body armor, edentulous jaws, absence of pelvic fins and intermuscular bones, gill opening reduced to a pore on the opercular membrane and mainly by the fact that the males carry the eggs in a breeding pouch. Although this group is so peculiar and morphologically distinct, osteological studies are rare and focused mainly on the seahorses (genus Hippocampus) and there are no phylogenetic studies based on morphological characters. In this study, it was possible to gather information about the osteology of P. brasiliensis that allowed comparing and discussing morphological questions that are being debated along the years in different studies available on the literature, such as the existence of the metapterygoid, and branchial arch and pectoral girdle arrangement. The osteology of P. brasiliensis was conducted taking in consideration these questions in order to create a basis for future anatomical and phylogenetical studies in this group.
52

O desenvolvimento embrionário da Piapara - Leporinus elongatus (Pisces, Anostomidae) utilizando marcadores ósseos / Embryonic development of piapara - Leporinus elongatus (Pisces, Anostomidae) using bone markers

Sousa, Erika Zolcsak de 21 May 2014 (has links)
O conhecimento dos estágios iniciais do desenvolvimento embrionário de peixes é de extrema importância para o estudo de espécies nativas com potencial para a piscicultura, uma vez que permite o estabelecimento de diretrizes para a criação destes animais. Este projeto estudou o desenvolvimento embrionário da piapara (Leporinus elongatus), um peixe de grande importância na pesca esportiva e profissional na bacia dos rios Pardo e Jequitinhonha, visando compreender as fases desse animal em diversos estágios de desenvolvimento, utilizando marcadores ósseos que possibilitaram visualizar o desenvolvimento ósseo da espécie. As Proteínas Ósseas Morfogenéticas (BMP-2 e BMP-4) são consideradas moléculas essenciais reguladoras no desenvolvimento embrionário e na formação óssea, sendo ainda pouco estudadas em peixes; tais proteínas puderam ser observadas apenas no estádio larval até o período juvenil, não sendo evidenciadas nos estágios anteriores. Foram utilizadas também técnicas de Microscopia Eletrônica de Varredura e histológicas, onde foi possível visualizar as fases principais do desenvolvimento embrionário, entre elas, clivagens, diferenciação do embrião, formação dos órgãos principais, abertura de boca, pigmentação dos olhos, surgimento das nadadeiras e sistema branquial, dados estes que facilitam a compreensão sobre a ontogenia; além de criar dados embriológicos e anatômicos dessa espécie ainda pouco explorada, conhecimentos estes, imprescindíveis à biologia pesqueira e cultivo das mesmas, sendo também um auxiliar a novas pesquisas. / The knowledge of the early stages of embryonic development in fish is of great importance for the study of native species with potential for aquaculture, since it allows the establishment of guidelines for the breeding of these animals. This project studied the embryonic development of piapara (Leporinus elongatus), a fish of great importance in professional and amateur fishing from the basin of the Pardo and Jequitinhonha rivers, aiming to understand the various stages of development, using bone markers that allowed observation of the bone development in this species. The Bone Morphogenetic Proteins (BMP-2 and BMP-4) are known as key regulatory molecules in embryonic development and bone formation, and information on this subject is scarce in fish. Results shown these proteins could be observed only between the larval to the juvenile stage, not being seen at earlier stages. Scanning electron microscopy and histological techniques, where it was possible to observe the main stages of embryonic development , including , cleavage , embryo differentiation , development of major organs , mouth opening , eye pigmentation , appearance of fins and gills system. This data contributed for the understanding of ontogeny, and provided embryological and anatomical data that may help other studies like reproductive biology of this species that surely will improve reproductive techniques, important goal for raising the piapara.
53

I människans tjänst? : en studie om relationen mellan människa och djuroffer i gravar från yngre järnåldern / In the service of man? : a study of the relationship between humans and animal sacrifices in graves from late Iron Age

Karlsson, Jennie January 2009 (has links)
<p>By examine cremated remains from graves dated to late Iron Age I wanted to find out what sorts of animals were placed in the graves. But also to see if the animal sacrifices had any connection to the Old Norse religion. The osteological material that were analysed were from both cremated humans and animals and had been dated to Viking Age. The material is from burial ground 59 at Laxare, Boge parish on Gotland. In addition to the human remains, the material contains bones from horse, cattle, sheep/goat, pig, dog, cat, bear, birds and fish. The combination between the species seems to be common all over Scandinavia during the late Iron Age. Except from analysing the material from Laxare I also studied litterature written by other scientist on the subject of animals in Old Norse religion. This was made to understand as much as possible about the religion and how people looked upon animals before Christianity.</p><p>It seemed that animals were very important in religion during the Viking Age in this area on Gotland. Some of the species that were sacrifices in the graves had big importance in peoples daily life but also in myths. The world needed humans, animals and gods to survive and everything were depending on the harmony between them. The horse was clearly a religious animal, and it shows both in the archaeological material and in the written stories from this time. Even cattle, goat and pig are other animals that describe to be important for the religion. The dog seems to be important in the archaeological material but is not mentioned very much in the written myths.</p><p>It is rather clear that the animal sacrificed in graves from the late Iron Age in Sweden is not only for food in the afterlife but also has a very important meaning for the religion and peoples understanding about Cosmos.</p>
54

Är vi lika dem? : en kraniestudie av hominider ur ett evolutionistiskt perspektiv / Do we look like them? : a studie of craniums from hominids in an evolutionary perspective

Karlsson, Jennie January 2008 (has links)
<p>By examine plastic craniums from eight different hominids I wanted to find morfological characteristics that agreed with those of modern humans. The species that were selected had a plastic casting of its cranium in the laboratory at Gotland University. My focus was on species from the family <em>Australopithecius </em>and <em>Homo </em>and only working with their craniums. And this because the cranium and the theeth shows the most visible morfological characteristics between the different hominids. I also wanted,in a small part of the essay, to write about the differences in now living primates and humans skulls.</p><p>Except from analysing the plastic castings I also studied surveys written by other scientist on the same subject. And in that chapter write as much about the whole skeleton as possible, eventhough that was not my main field, but I wanted to give the readers an overview of the species before the analysis took place.</p><p>The most visible morfological characteristics is shown in the theeth because the diet changed during the million years that the evolution took place. It is possible to see the development in <em>Foramen magnum </em>too, the hole at the base of the skull were the vertebrate connects with the cranium. This hole gets more central over time showing that the species got more biped and started to walk upright on two legs just like humans do today. There are of course many more characteristics that are able to be seen that seperates us from the extinct hominids, but many of them are the same. If you look closely at the different craniums you can see how the fantastic evolution formed humans out of apes.</p><p>It has to be mentioned that the scientist have many different theoris about the evolution, the species and who are the real ancestors to humans and I think the disagreement will continue for many years to come.</p>
55

Djurhushållningen i Västergarn : en osteoarkeologisk fallstudie av animalt benmaterial från Snauvalds 1:2, Västergarn, Gotland / Animal husbandry in Västergarn parish : an osteoarchaeological case study of animal bone material from Snauvalds 1:2, Västergarn, Gotland

Hammarsten, Eleonor January 2013 (has links)
In this Bachelor thesis an animal bone material from Västergarn parish is analyzed and discussed. The purpose of this thesis is to gain more knowledge about the Viking Age/Early Medieval Västergarn. Västergarn has a few remains from former days which have been discussed throughout the years and are still a bit of a mystery for archaeologists. The main focus is to inquire into whether Västergarn was an urban, complex society or a rural settlement. This will be done by studying the animal husbandry from the property of Snauvalds 1:2. The animal bones have been typed, and sex and age estimations have been made on the most common domestic animals, ergo cattle, sheep/goat and pig. The result from the analysis shows that Västergarn has tendencies of both countryside settlement and a more urban society and the final conclusion is that it has most probably been a trading place or a market place considering its closeness to a Viking Age harbor.
56

Phylogenetics of Pinguipedidae from Taiwan

Kuo, Hsiao-Ching 24 July 2007 (has links)
Family Pinguipedidae belong to the class Actinopterygii, subclass Neopterygii, order Perciformes, suborder Trachinoidei. Currently the interrelationships of the genera within this family and among the families in the Trachinoidei remain unequivocal. Also, whether the Cheimarrichthys should be included in the family Pinguipedidae has also been a controversial issue. This study aimed to reconstruct phylogenetic hypotheses in order to resolve these questions. Species of the Parapercis and Kochichtys in the family Pinguipedidae occur Taiwan. This study used osteological characters, 16S rRNA and Cyt b sequences to conduct phylogenetic analysis such that hypotheses can be proposed. The results revealed the monophyly of Parapercis, a taxonomic view consistent to the prevailary classification. Summarizing all the results, the 17 Parapercis species analysed can be divided into 4 groups. They are (1) Parapercis aurantiaca¡BP. decemfasciata¡BP. mimaseana¡BP. multifasciata¡BP. muronis¡Btwo morphotypes of P. sexfasciata¡F(2) P. cephalopunctata¡BP. clathrata¡BP. hexophthalma¡BP. kamoharai¡BP. tetracantha¡BP. xanthozona¡F(3) P. cylindrica and P. snyderi¡F(4) P. maculata¡BP. ommatura and P. somaliensis. Two color morphotypes have been shown for Parapercis sexfasciata. Data of the present study revealed that the ¡§ autapomorphic¡¨ osteological character known only in Kochichtys also occurred in three Parapercis species. This result supports a close relationship between these species. However, it also challenges the validity of the generic status of Kochichtys. About the dabate of the phylogenetic position of Cheimarrichthys, it should be put into its own family, Cheimarichthyide, rather than placed in the Pinguipedidae. The hypothesis for the sister group of Pinguipedidae to the Cheimarichthyide is not supported by all the data in this study completely. Morphological and molecular evidences are incongruence for closest phylogenetic relationship. Similar results were also obtained when the molecular sequences were analysed using different methods. More data analyses are needed for complete and reliable results. The present study suggests that the Trachinoidei is not a monophyletic group.
57

Forensisk arkeologi : Har forensisk arkeologi en framtid i Sverige?

Delic, Admira January 2008 (has links)
ABSTRACT Delic, Admira. 2007. Forensisk arkeologi: Har forensisk arkeologi en framtid i Sverige? (Forensic archaeology: Is there a future for forensic archaeology in Sweden? C-uppsats i arkeologi. Högskolan i Kalmar ht 2007) This paper is about what forensic archaeology means, how the work is done, what methods are used in a forensic investigation. It is discussed whether there is any difference between how archaeologists and forensic scientists work. Interviews with archaeologists, an osteologists and a forensic scientist are made in order to get a wider perspective of the subject. Keywords: Sweden, Forensic archaeology, criminal science, ostoelogy, AFFA
58

A bioarchaeological approach to stress and health in medieval Denmark: dental enamel defects and adult health in two medieval Danish populations

Gamble, Julia A. 12 January 2015 (has links)
This research engages in a bioarchaeological analysis of two medieval Danish sites using combined microscopic and macroscopic methods in order to investigate three objectives. The first was to consider the relationship between childhood stress and adult health through the joint consideration of microscopic enamel defects and adult health indicators. Given the context of these populations over a period of history characterized by changing climate and socioeconomic conditions, punctuated by famine and plague, this research also sought to examine temporal patterns in health and stress. Given the increased urbanization over the medieval period, the final objective was to consider health patterns between rural and urban populations. The results showed that the number of stress events did have an impact on later life mortality, and that there was differential expression of this relationship between males and females and between surface and internal enamel defects. A statistically significant decrease in stature was apparent after 1350 A.D. as well as an insignificant increase in tuberculosis and treponema, but an insignificant increase in age at death over time. The inter-site comparison showed higher rates of infectious disease at the rural site of Sejet, with tuberculosis in particular being significantly higher in females at Sejet. Mean age at death was also significantly lower at Sejet for the study sample, but a consideration of the broader cemetery sample showed no significant site differences, suggesting that this might be a sampling phenomenon. These patterns likely reflect the complex nature of the rural and urban interaction during this period, but also emphasize the need for further sampling. This research points to the complex relationship between stress and health and outlines the importance of developing more comprehensive etiological models and operational definitions for identifying stress indicators in dental enamel.
59

I människans tjänst? : en studie om relationen mellan människa och djuroffer i gravar från yngre järnåldern / In the service of man? : a study of the relationship between humans and animal sacrifices in graves from late Iron Age

Karlsson, Jennie January 2009 (has links)
By examine cremated remains from graves dated to late Iron Age I wanted to find out what sorts of animals were placed in the graves. But also to see if the animal sacrifices had any connection to the Old Norse religion. The osteological material that were analysed were from both cremated humans and animals and had been dated to Viking Age. The material is from burial ground 59 at Laxare, Boge parish on Gotland. In addition to the human remains, the material contains bones from horse, cattle, sheep/goat, pig, dog, cat, bear, birds and fish. The combination between the species seems to be common all over Scandinavia during the late Iron Age. Except from analysing the material from Laxare I also studied litterature written by other scientist on the subject of animals in Old Norse religion. This was made to understand as much as possible about the religion and how people looked upon animals before Christianity. It seemed that animals were very important in religion during the Viking Age in this area on Gotland. Some of the species that were sacrifices in the graves had big importance in peoples daily life but also in myths. The world needed humans, animals and gods to survive and everything were depending on the harmony between them. The horse was clearly a religious animal, and it shows both in the archaeological material and in the written stories from this time. Even cattle, goat and pig are other animals that describe to be important for the religion. The dog seems to be important in the archaeological material but is not mentioned very much in the written myths. It is rather clear that the animal sacrificed in graves from the late Iron Age in Sweden is not only for food in the afterlife but also has a very important meaning for the religion and peoples understanding about Cosmos.
60

Är vi lika dem? : en kraniestudie av hominider ur ett evolutionistiskt perspektiv / Do we look like them? : a studie of craniums from hominids in an evolutionary perspective

Karlsson, Jennie January 2008 (has links)
By examine plastic craniums from eight different hominids I wanted to find morfological characteristics that agreed with those of modern humans. The species that were selected had a plastic casting of its cranium in the laboratory at Gotland University. My focus was on species from the family Australopithecius and Homo and only working with their craniums. And this because the cranium and the theeth shows the most visible morfological characteristics between the different hominids. I also wanted,in a small part of the essay, to write about the differences in now living primates and humans skulls. Except from analysing the plastic castings I also studied surveys written by other scientist on the same subject. And in that chapter write as much about the whole skeleton as possible, eventhough that was not my main field, but I wanted to give the readers an overview of the species before the analysis took place. The most visible morfological characteristics is shown in the theeth because the diet changed during the million years that the evolution took place. It is possible to see the development in Foramen magnum too, the hole at the base of the skull were the vertebrate connects with the cranium. This hole gets more central over time showing that the species got more biped and started to walk upright on two legs just like humans do today. There are of course many more characteristics that are able to be seen that seperates us from the extinct hominids, but many of them are the same. If you look closely at the different craniums you can see how the fantastic evolution formed humans out of apes. It has to be mentioned that the scientist have many different theoris about the evolution, the species and who are the real ancestors to humans and I think the disagreement will continue for many years to come.

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