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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.
71

Strontium apatite nanoparticle bioactive bone cement from biomaterial development to pre-clinical evaluations /

Lam, Wing-moon, Raymond. January 2009 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2010. / Includes bibliographical references (leaves 201-220). Also available in print.
72

The isotopic composition of lead and strontium from the volcanic rocks of the islands of the South Pacific

Swainbank, Ian G. January 1968 (has links)
Thesis--Columbia University. / Bibliography: leaves 121-124.
73

Doped alkaline earth (nitride) hydrides /

Verbraeken, Maarten Christiaan. January 2009 (has links)
Thesis (Ph.D.) - University of St Andrews, June 2009.
74

Étude des phosphoapatites calco et strontioeuropiques qui contiennent des anions bivalents dans les tunnels : synthèse, caractérisation, fluorescence.

Taitai, Abderrahim, January 1900 (has links)
Th.--Sci. phys.--Toulouse--I.N.P., 1985. N°: 100.
75

Utilização sistêmica de estrôncio não radioativo como potencializador da osseointegração de implantes : avaliação biomeânica, microtomográfica e histomorfométrica em ratos /

Scardueli, Cássio Rocha. January 2014 (has links)
Orientador: Elcio Marcantonio Junior / Co-orientador: Rosemary Adriana C. Marcantonio / Banca: Luis Antonio Pugliessi Lima / Banca: Rubens Spin Neto / Resumo: Medicamentos a base de bisfosfonatos têm sido amplamente empregados para tratar enfermidades como osteoporose, mieloma múltiplo, doenças reumáticas e neoplasias com metástases ósseas. No entanto, não podem ser usados rotineiramente na clínica odontológica em favor da maior reparação óssea e osseointegração devido a seus mecanismos específicos e por estarem constantemente relacionados a problemas como alta permanência da droga no organismo e risco de necroses ósseas. Medicamentos a base de estrôncio surgem como novas formas de tratamento para pacientes osteoporóticos bem como uma possível indicação para o uso coadjuvante em procedimentos cirúrgicos, favorecendo a nova formação óssea. Diante das vantagens oferecidas pelos medicamentos a base de estrôncio, como ranelato de estrôncio e cloreto de estrôncio/carbonato de estrôncio, este trabalho teve como objetivo avaliar a osseointegração de implantes em tíbias de ratos. Foram utilizados 70 ratos Rattus Norvegicus, machos, divididos aleatoriamente em 5 grupos: S-Controle (soro); RE 50 (Ranelato de Estrôncio 50 mg); RE 625 (Ranelato de Estrôncio 625 mg); ClECaE 30 (Cloreto Estrôncio e Carbonato Estrôncio 30 mg); ClECaE 365 (Cloreto Estrôncio e Carbonato de Estrôncio 365 mg). Os medicamentos foram administrados diariamente, via gavagem, de acordo com cada grupo, iniciando 15 dias antes do procedimento cirúrgico (1 implante em cada tíbia), persistindo até o final do experimento 15 ou 60 dias. Testes biomecânicos foram realizados com os implantes do lado direito através do contra-troque de remoção, e os implantes no lado esquerdo foram realizadas microtomografias e análises histomorfométricas. Os resultados mostraram uma melhora na osseointegração, principalmente nos grupos ranelato estrôncio 62mg e cloreto estrôncio/carbonato estrôncio 365mg nos testes biomecânicos e microtomográficos. O medicamento a base de estrôncio teve uma influência positiva... / Abstract: Drugs containing bisphosphonates have been widely used to treat diseases such as osteoporosis, multiple myeloma, myeloproliferative disease and cancer with bone metastases. However, can not be used routinely in dental practice in favor of greater bone repair and osseointegration due to its specific mechanisms and are constantly related issues such as high permanence of the drug in the body and risk of bone necrosis. Drugs based on strontium emerge as new forms of treatment for osteoporotic patients as well as a possible indication for adjuvant use in surgical procedures, promoting new bone formation. Given the advantages offered by drugs containing strontium as strontium ranelate and strontium chloride/strontium carbonate , this study aimed to evaluate the osseointegration of implants in rat tibia. Were used 70 rats Rattus Norvegicus, males, randomly divided into 5 groups: S (control-serum physiologic); RE50 (Strontium Ranelate 50 mg); RE 625 (Strontium Ranelate 625 mg); ClE/CaE 30 (Strontium Carbonate and Strontium Chloride 30 mg); ClE/CaE 365 (Strontium Carbonate and Chloride Strontium 365 mg). The drugs were administered daily by gavage according to each group, starting 15 days before surgery (1 implant in each tibia) and persisted until the end of the experiment 15 or 60 days. Biomechanical tests were performed with the right implants through shift against removal, and implants in the left side microtomography and histomorphometric analysis were performed. The results showed an improvement in osseointegration, especially in groups strontium ranelate 625mg and strontium cloride/strontium carbonate 365mg in microtomography and biomechanical testing. The drug strontium base had a positive influence on osseointegration of implants, especially strontium chloride/strontium carbonate, can be incorporated into prevention, treatments of pathologies and surgical procedures as adjunct to implant placement. / Mestre
76

Foreigners in Fröjel?: a study of mobility on a Viking Age port of trade in Gotland, Sweden

Peschel, Emily Maria Hellzen 12 March 2016 (has links)
Ridanäs was an important port of trade on the island of Gotland, Sweden, in use during the 7-11th centuries, AD. Excavations have revealed the presence of two Viking Age (800-1070 AD) graveyards containing over 80 individuals. This study examined the remains of 60 of these individuals buried in the Viking graveyards. Strontium isotope analysis was used to determine whether they were local or non-local to the trading port. It was hypothesized that the Ridanäs population would consist of locals and non-locals who came to Gotland to take advantage of its successful trade economy. 13 archaeological fauna samples were analyzed in order to define the local bioavailable strontium isotope baseline range. Results showed that only 4 of the 60 individuals were non-local to Gotland, indicating that non-locals did not seek long-term residency at this port of trade.
77

Using strontium isotope analysis on modern populations to determine geolocation reliability in a forensic context

Lustig, Adeline January 2013 (has links)
Thesis (M.S.F.S.) / Positive identification of skeletonized human remains is a difficult task when dental records and/or DNA are unavailable. Through archaeological research, strontium (Sr) isotope analysis has successfully been used to trace an individual back to their place of birth using cortical bone and tooth enamel. This method has the potential, in forensic anthropological science, to help narrow down the search for missing persons to a specific geographical location. It has not been tested thoroughly on modern populations though, which is needed before applying in a forensic setting. This study used dental enamel from teeth of 78 individuals in the New England region of the United States (U.S.). The birthplaces represented by these individuals include New England and the greater Northeast of the U.S., Northwest region of the U.S., Central America, Caribbean Islands, West Africa, and Europe. Local faunal and water samples were also collected for local range comparisons. The samples were cleaned, approximately 10 mg of enamel removed from each tooth, acid washed, dried, and dissolved in nitric acid before analyzing the samples using a thermal ionization mass spectrometer (TIMS) for analysis of 87Sr/86Sr ratios. The human 87Sr/86Sr ratios were grouped by geographical region. An analysis of variance was used to test for regional variation and significant differences were found. The samples from the U.S. (excluding those from the Northwest) were significantly different from the samples in Central America, Caribbean Islands, West Africa, and Europe. Central American samples were also significantly different from the other groups. No significant differences were observed between the Caribbean Islands, West Africa and Europe. A significant difference was seen between the strontium ratios in the West Africa group based on bottled water vs. tap water that individuals reported drinking. The faunal samples from Pembroke, MA and water sample from Braintree, MA were not significantly different from the New England human samples, but the Brighton, MA water sample was significantly different. Based on the data, regional differences in 87Sr/86Sr ratios are detectable using strontium isotope analysis, yet a larger sample size for each of the regions is needed to strengthen the statistical results. The results suggest that the differences observed are due to a combination of geological effects and influences from the globalization of food. Further research is warranted by combining the analysis of hydrogen (δ2H) and oxygen (δ18O) isotopes to the strontium analysis. This will complement the strontium data by providing more insight to the local drinking water and potential effects of an increasingly homogenous diet within cultural regions.
78

Laser Cooling and Trapping of Neutral Strontium for Spectroscopic Measurements of Casimir-Polder Potentials

Cook, Eryn 10 April 2018 (has links)
Casimir and Casimir-Polder effects are forces between electrically neutral bodies and particles in vacuum, arising entirely from quantum fluctuations. The modification to the vacuum electromagnetic-field modes imposed by the presence of any particle or surface can result in these mechanical forces, which are often the dominant interaction at small separations. These effects play an increasingly critical role in the operation of micro- and nano-mechanical systems as well as miniaturized atomic traps for precision sensors and quantum-information devices. Despite their fundamental importance, calculations present theoretical and numeric challenges, and precise atom-surface potential measurements are lacking in many geometric and distance regimes. The spectroscopic measurement of Casimir-Polder-induced energy level shifts in optical-lattice trapped atoms offers a new experimental method to probe atom-surface interactions. Strontium, the current front-runner among optical frequency metrology systems, has demonstrated characteristics ideal for such precision measurements. An alkaline earth atom possessing ultra-narrow intercombination transitions, strontium can be loaded into an optical lattice at the “magic” wavelength where the probe transition is unperturbed by the trap light. Translation of the lattice will permit controlled transport of tightly-confined atomic samples to well-calibrated atom- surface separations, while optical transition shifts serve as a direct probe of the Casimir-Polder potential. We have constructed a strontium magneto-optical trap (MOT) for future Casimir-Polder experiments. This thesis will describe the strontium apparatus, initial trap performance, and some details of the proposed measurement procedure.
79

Utilização sistêmica de estrôncio não radioativo como potencializador da osseointegração de implantes: avaliação biomeânica, microtomográfica e histomorfométrica em ratos

Scardueli, Cássio Rocha [UNESP] 25 March 2014 (has links) (PDF)
Made available in DSpace on 2014-12-02T11:16:37Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-03-25Bitstream added on 2014-12-02T11:21:07Z : No. of bitstreams: 1 000800880.pdf: 720556 bytes, checksum: 98904c318206483604d36216d6313baf (MD5) / Medicamentos a base de bisfosfonatos têm sido amplamente empregados para tratar enfermidades como osteoporose, mieloma múltiplo, doenças reumáticas e neoplasias com metástases ósseas. No entanto, não podem ser usados rotineiramente na clínica odontológica em favor da maior reparação óssea e osseointegração devido a seus mecanismos específicos e por estarem constantemente relacionados a problemas como alta permanência da droga no organismo e risco de necroses ósseas. Medicamentos a base de estrôncio surgem como novas formas de tratamento para pacientes osteoporóticos bem como uma possível indicação para o uso coadjuvante em procedimentos cirúrgicos, favorecendo a nova formação óssea. Diante das vantagens oferecidas pelos medicamentos a base de estrôncio, como ranelato de estrôncio e cloreto de estrôncio/carbonato de estrôncio, este trabalho teve como objetivo avaliar a osseointegração de implantes em tíbias de ratos. Foram utilizados 70 ratos Rattus Norvegicus, machos, divididos aleatoriamente em 5 grupos: S-Controle (soro); RE 50 (Ranelato de Estrôncio 50 mg); RE 625 (Ranelato de Estrôncio 625 mg); ClECaE 30 (Cloreto Estrôncio e Carbonato Estrôncio 30 mg); ClECaE 365 (Cloreto Estrôncio e Carbonato de Estrôncio 365 mg). Os medicamentos foram administrados diariamente, via gavagem, de acordo com cada grupo, iniciando 15 dias antes do procedimento cirúrgico (1 implante em cada tíbia), persistindo até o final do experimento 15 ou 60 dias. Testes biomecânicos foram realizados com os implantes do lado direito através do contra-troque de remoção, e os implantes no lado esquerdo foram realizadas microtomografias e análises histomorfométricas. Os resultados mostraram uma melhora na osseointegração, principalmente nos grupos ranelato estrôncio 62mg e cloreto estrôncio/carbonato estrôncio 365mg nos testes biomecânicos e microtomográficos. O medicamento a base de estrôncio teve uma influência positiva... / Drugs containing bisphosphonates have been widely used to treat diseases such as osteoporosis, multiple myeloma, myeloproliferative disease and cancer with bone metastases. However, can not be used routinely in dental practice in favor of greater bone repair and osseointegration due to its specific mechanisms and are constantly related issues such as high permanence of the drug in the body and risk of bone necrosis. Drugs based on strontium emerge as new forms of treatment for osteoporotic patients as well as a possible indication for adjuvant use in surgical procedures, promoting new bone formation. Given the advantages offered by drugs containing strontium as strontium ranelate and strontium chloride/strontium carbonate , this study aimed to evaluate the osseointegration of implants in rat tibia. Were used 70 rats Rattus Norvegicus, males, randomly divided into 5 groups: S (control-serum physiologic); RE50 (Strontium Ranelate 50 mg); RE 625 (Strontium Ranelate 625 mg); ClE/CaE 30 (Strontium Carbonate and Strontium Chloride 30 mg); ClE/CaE 365 (Strontium Carbonate and Chloride Strontium 365 mg). The drugs were administered daily by gavage according to each group, starting 15 days before surgery (1 implant in each tibia) and persisted until the end of the experiment 15 or 60 days. Biomechanical tests were performed with the right implants through shift against removal, and implants in the left side microtomography and histomorphometric analysis were performed. The results showed an improvement in osseointegration, especially in groups strontium ranelate 625mg and strontium cloride/strontium carbonate 365mg in microtomography and biomechanical testing. The drug strontium base had a positive influence on osseointegration of implants, especially strontium chloride/strontium carbonate, can be incorporated into prevention, treatments of pathologies and surgical procedures as adjunct to implant placement.
80

Efeito da adicao de chumbo na formacao de fases supercondutoras em ceramicas de Bi-Sr-Ca-Cu-O

MARTINELLI, ANTONIO E. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:36:38Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:09Z (GMT). No. of bitstreams: 1 04226.pdf: 1346289 bytes, checksum: ae51647be934d5e52ce7e2787d3ee5b5 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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