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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

The earliest instrument : ritual power and fertility magic of the flute in Upper Paleolithic culture

Neal, Lana Carol 02 March 2015 (has links)
The present study examines the earliest known musical instruments, Upper Paleolithic flutes. Flutes dating to the Upper Paleolithic period are the oldest musical instruments that have survived in the archeological record. These have been discovered at archeological sites in Europe dating from approximately 40,000 to 15,000 years ago. Although humans were most likely creating music prior to this time, the people who entered Europe approximately 40,000 years ago began to create musical instruments that have survived to the present day. This study investigates the significance and function of these instruments in Upper Paleolithic culture. Analysis of the artifacts is followed by discussions of archeological contexts, Upper Paleolithic art, ethnographic comparison, and the flute in mythology. Such diverse sources provide multiple layers of evidence regarding the role of the flute in Upper Paleolithic culture. The phallic shape of the instrument and the fact that it is played with the breath, also a symbol of life, connect the flute with the fertility of humans, plants, and animals, the cycle of life and death, and rebirth after death. There is evidence that the flute was intrinsically linked to these themes even in the Upper Paleolithic period, in which the flute was of vital significance, as it was magically imbued with the power to bestow life. / text
32

Phosphorus and Sulfur Cosmochemistry: Implications for the Origins of Life

Pasek, Matthew Adam January 2006 (has links)
Phosphorus is a key element for life. This work reviews the role of phosphorus in life. Theories on the origin of life are confounded by a lack of reactive phosphorus, and attempts to overcome the dearth of reactive phosphorus must employ unrealistic phosphorus compounds, energetic organic compounds, or unusual physical conditions.Meteoritic schreibersite provided an abundant source of reactive phosphorus for the early Earth. Water corrodes schreibersite to form a mixed valence series of phosphorus compounds. Schreibersite corrosion was studied by a variety of techniques, including NMR, MS, XRD, and EPR. Reduced phosphorus in schreibersite corrodes through release of phosphite radicals which react with other radicals to form the phosphorus compounds observed. These radicals are also capable of phosphorylating simple organic compounds to form P-C and P-O-C linkages.The meteoritic mass flux was calculated using the mass frequency distribution of several meteorite collections. Much of the meteoritic mass that falls to the Earth is composed of metallic material which supplies abundant reactive phosphorus. Meteorites are a comparatively poorer source of carbon. Craters concentrate both reduced phosphorus and organic compounds through geomorphologic processes.Phosphorus and sulfur biochemistry are intricately linked in metabolism. The cosmochemistry of sulfur was studied in depth using changing C/O ratios, sulfide formation kinetics, and gas diffusion. The results have implications for meteorites, studies of Jupiter, and of protoplanetary disks.
33

The Ostrich Eggshell Beads of Mlambalasi rockshelter, southern Tanzania

Miller, Jennifer M Unknown Date
No description available.
34

Characterization of Supramolecular Polymer Systems Composed of Prebiotically Plausible Recognition Units

Khanam, Jaheda 08 August 2014 (has links)
Supramolecular polymers have a practical impact on the healthcare field as they can act as scaffolds to repair parts of organs such as the brain or heart. In addition, they can provide insight into theories relating to the origins of life. For instance, the hypothesis that RNA played a more important role in early biology, the RNA World hypothesis, would be strengthened if there were a way to show the spontaneous formation of RNA-like polymers from monomer units. However, the natural nucleobases do not assemble at the monomer level, nor do they form nucleosides readily with ribose, leading some to speculate that the first nucleobases may have been different from the ones used in biology today. This conundrum encouraged us to begin looking for alternative nucleobases that are able to self-assemble into polymers capable of storing information. Our lab has recently demonstrated that a modified 2,4,6-triaminopyrimidine (TAP) will assemble with cyanuric acid (CA) in water through interactions that are analogous to those between complementary nucleobases found in DNA and RNA. When TAP is modified at one of its three faces, it can pair through specific hydrogen bonding with CA on two of its faces, forming rosette structures. These rosettes self-assemble to form extremely long structures through the stacking of tens of thousands of rosettes. In this study we are investigating prebiotically relevant syntheses of TAP nucleosides. Using chromatography techniques and nuclear magnetic resonance we found that the unmodified TAP with D-ribose formed nucleosides in 60% yields with the major product (20%) being a C-nucleoside 5-β-ribofuranosyl-2,4,6-triaminoprymidine or TARC. TARC forms hydrogels with CA, both in the crude reaction and after purification, indicative of the formation of supramolecular polymers out of a complex mixture. The results of this study provide support for the possibility of pre-RNA molecules.
35

Hudba a emoce: psychologické aspekty ve vztahu k původu a vývoji hudby / Music and Emotions: Psychological Aspects with Regard to the Origin and Evolution of Music

Mlejnek, Roman January 2016 (has links)
Roman Mlejnek Music and Emotions: Psychological Aspects with Regard to the Origin and Evolution of Music Dissertation thesis Abstract Music and emotion is of deep interest in today's research in many different disciplines. This thesis summarizes contemporary knowledge of emotion and analyses music's related phenomena which could enlighten the importance of emotionality (sound, speech, play, movement). Interindividual differences are discussed mainly with regard to musicality. Selected problems (especially from music aesthetics and music theory) are commented from the point of view of contemporary psychology. In the first place, this thesis notices common psychological mechanisms working in music of different types, times and cultures. Special consideration is devoted to the question of the origins of music and it's evolutionary basis. The thesis includes two empirical studies based on questionnaire surveys. The first one explores Janáček's collection of speech melodies with regard to it's potential as research stimuli for research in music and speech. The second one deals with physically experienced reactions and is focussed on musicians and their differences to non- musicians. Key words: music, emotion, origins of music
36

Zooarchaeological and Taphonomic Analyses of Pleistocene Vertebrate Fauna from the Middle and Later Stone Age Occupations at Contrebandiers Cave, Atlantic Coast, Morocco

January 2018 (has links)
abstract: This dissertation research describes the hunting behavior of early modern humans through the analysis of vertebrate faunal remains from Contrebandiers Cave, Morocco. Contrebandiers Cave is located in the town of Témara and is roughly 250 meters from the current shoreline of the Atlantic Ocean. The cave was excavated in the 1950s and 1970s by l’Abbé Roche, and again starting in 2007 by Dibble and El Hajraoui with total station plotting of finds. Contrebandiers Cave contains Middle Stone Age (MSA) deposits dated to Marine Isotope Stages (MIS) 5e, 5d and 5c, ~120,000 to ~96,000 years ago. The Later Stone Age (LSA) deposits are dated to MIS 2, ~20,000 years ago. The entirety of the ~12,000 vertebrate faunal remains from Dibble and El Hajraoui’s excavation were analyzed for taxonomic and taphonomic identification. A total of 67 vertebrate taxa were identified and include ungulates, carnivores, lagomorphs, birds, tortoises, snakes and fish. The faunal remains from Contrebandiers Cave preserve surface modification that indicates both humans and carnivores acted as agents of prey accumulation. Skeletal element representation and surface modification of ungulate remains suggest that humans had primary access to small, medium and large-bodied prey. In the MSA levels, carnivore skeletal remains preserve surface modification that is interpreted as being indicative of behavior associated with skinning for fur removal. The vertebrate faunal remains from MIS 5e and 5d indicate that humans were hunting grazers and mixed feeders from open habitats and suids from mixed habitats. The faunal remains from MIS 5c indicate that humans focused less on suids and more on mixed feeders from open habitats. The vertebrate faunal remains from MIS 2 reveal humans hunting grazers from dry, open habitats. This research provides a description of human hunting behavior in North Africa, and contributes to our understanding of early modern human behavior prior to dispersal out of Africa. / Dissertation/Thesis / Doctoral Dissertation Anthropology 2018
37

Pathogen Origins and Evolution in the New World: A Molecular and Bioarchaeological Approach to Tuberculosis and Leishmaniasis

January 2014 (has links)
abstract: Studies of ancient pathogens are moving beyond simple confirmatory analysis of diseased bone; bioarchaeologists and ancient geneticists are posing nuanced questions and utilizing novel methods capable of confronting the debates surrounding pathogen origins and evolution, and the relationships between humans and disease in the past. This dissertation examines two ancient human diseases through molecular and bioarchaeological lines of evidence, relying on techniques in paleogenetics and phylogenetics to detect, isolate, sequence and analyze ancient and modern pathogen DNA within an evolutionary framework. Specifically this research addresses outstanding issues regarding a) the evolution, origin and phylogenetic placement of the pathogen causing skeletal tuberculosis in New World prior to European contact, and b) the phylogeny and origins of the parasite causing the human leishmaniasis disease complex. An additional chapter presents a review of the major technological and theoretical advances in ancient pathogen genomics to frame the contributions of this work within a rapidly developing field. This overview emphasizes that understanding the evolution of human disease is critical to contextualizing relationships between humans and pathogens, and the epidemiological shifts observed both in the past and in the present era of (re)emerging infectious diseases. These questions continue to be at the forefront of not only pathogen research, but also bioarchaeological and paleopathological scholarship. / Dissertation/Thesis / Doctoral Dissertation Anthropology 2014
38

Implication des protéines HMGA et HMGA2 dans les changements du programme de réplication au cours de la sénescence cellulaire / HMGA proteins modify the replication program during senescence

Kahli, Malik 20 September 2011 (has links)
La sénescence, considérée comme étant un arrêt irréversible du cycle cellulaire, se caractérise par des changements drastiques de l'expression génique et de l'organisation de la structure de la chromatine. En effet, il se forme des foyers denses d'hétérochromatine au sein du noyau (SAHF) et ces modifications s'accompagnent d'un déclin progressif de la capacité à dupliquer le génome. Au cours de ma thèse, j'ai voulu savoir si ces modifications de la chromatine induite par les SAHF pouvaient influer sur le programme de réplication et changer la distribution des origines de réplication sur le génome au cours du processus d'entrée en sénescence réplicative des cellules. Nous avons donc, dans un premier temps, comparé par peignage moléculaire de l'ADN réplicatif la distribution des origines de réplication de cellules primaires prolifératives et sénescentes. Nous avons également cartographié l'ensemble de leurs origines de réplication sur la totalité du génome en purifiant les brins naissants aux origines de réplication que nous avons couplé à une analyse de séquençage à haut débit.Les protéines HMGA1 et HMGA2 étant des éléments précurseurs essentiels à la mise en place des SAHF, nous avons créé des lignées cellulaires qui, en sur-exprimant de façon inductibles ces protéines, induit une sénescence prématurée. Nous avons réalisé le même type d'analyses sur ces cellules afin de mettre en évidence le rôle de ces protéines dans les modifications du programme de réplication que nous avons observé au cours de l'entrée en sénescence de ces différents types cellulaires. / Senescence, considered as an irreversible cell cycle arrest, is characterized by dramatic changes in genes expression and chromatin organisation forming dense heterochromatic foci (SAHF). These changes are concomitant to a progressive decline of the capactity to replicate the genome. My PhD topic was to investigate whether the chromatin changes induced by SAHF formation could influence the replication program and modify the origin distribution along the genome at replicative senescence. We first compared the origin distribution of proliferative and pre-senescent primary fibroblasts by DNA molecular combing. Then, we mapped the origins positions in whole human genome by using the nascent strand purification assay coupled to deep sequencing.As HMGA1 and HMGA2 proteins are essential to induce SAHF formation, we designed inducible cell lines wich overexpress these proteins, triggering premature senescence. We made the same type of experiments in these cell lines in order to investigate the implication of these proteins on the changes of the replication program we observed during senescence.
39

Single Molecule Approaches to Mapping DNA Replication Origins

Liu, Victor 26 December 2017 (has links)
DNA replication is a fundamental process that is primarily regulated at the initiation step. In higher eukaryotes, the location and properties of replication origins are not well understood. Existing genome-wide approaches to map origins—such as nascent strand abundance mapping, Okazaki fragment mapping, or chromatin immunoprecipitation-based assays—average the behavior of a population of cells. However, due to cell-to-cell variability in origin usage, single molecule techniques are necessary to investigate the actual behavior of a cell. Here, I investigate the feasibility of using three single molecule, genome-wide technologies to map origins of replication. The Pacific Biosciences Single Molecule Real-Time (SMRT) sequencing technology, the BioNano Genomics Irys optical mapping technology, and the Oxford Nanopore Technologies MinION nanopore sequencing technology are promising approaches that can advance our understanding of DNA replication in higher eukaryotes.
40

Incarnation : Hindu and Christian thought

Francis, Benjamin Anthony 01 January 1953 (has links)
In writing these following pages, I have carefully avoided criticism of any kind. In these pages, I have mentioned the main differences between the Hindu and Christian faiths. I have treated this subject of incarnation with due respect to both the religions. If the subject could be discussed on an evaluative basis, then there would be the possibility of coming to the conclusion that there is less truth and more truth in different religious faiths. The most important consideration will be the truth value. In the incarnation stories, man is restored by God’s creative act to his original state.

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