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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

Individer från Bronsåldern och deras hälsa : En osteologisk analys av tre hällkistor från Nyplings i Lokrume socken, Gotland / Bronze Age individuals and their health : An osteological analysis of three stone cists from Nyplings, Lokrume parish, Gotland

Wallin, Emelie January 2023 (has links)
Bronsåldern är en period med många praktfulla fynd, långhus, storhögar och kremationsgravar. Nu under senare år har flera hällkistor med skelettgravar 14C daterats till bronsåldern, vilket öppnar upp för ny forskning inom tidsperioden när det gäller bland annat hälsoaspekter. Med hjälp av en kvalitativ humanosteologisk studie av två gravanläggningar i Nyplings 1:8, Lokrume socken på Gotland syftar uppsatsen till att påbörja forskningen inom bronsålderns folkhälsa samt motivera till fortsatta framtida forskning inom området. Totalt analyserades 2 598 benfragment med en totalvikt på 6 586 gram. Ett flertal osteologiska metoder användes för ålders- och könsbedömningar samt kvantifiering. Gravarna innehöll tolv individer där två beräknas vara barn och resterande i vuxen ålder. Endast tre individer har kunnat könsbedömmas varav en är av manligt kön och två av kvinnligt kön. Individerna har inte kunnat kroppslängds beräknas i brist på mätbara ben. Analysen av individerna i gravanläggningarna visade att flertalet skeletala förändringar drabbade individerna däribland ledförändringar, fraktur, skärskada och aktivitetsspår. En del av skeletten har uppvisat överlevnad av trauma, vilket är en indikation på en god grundhälsa. Men då majoriteten av individerna inte påvisar skeletala sjukdomar och dött vid en ung ålder har de enligt den osteologiska paradoxen överlag en dålig grundhälsa. De förändringar som har påträffats visar att individerna utsatts för en del smärta, obehag, stelhet och belastning under deras liv. Men trots allt har individerna levt ett relativt långt liv med bättre hälsa än andra individer både från Gotland och Skåne under Bronsåldern. / The Bronze Age is a period with many magnificent finds, naves, large mounds and cremation graves. Now in recent years, several stone cists with skeletal graves have been 14C dated to the Bronze Age, which opens up new research within the time period regarding, among other things, health aspects. With the help of a qualitative human osteological study of two burial sites in Nyplings 1:8, Lokrume parish on Gotland, the essay aims to begin research in Bronze Age public health and to motivate future research in the area. A total of 2 598 bone fragments with a total weight of 6 586 grams were analyzed. A number of osteological methods were used for age and gender assessments and quantification. The graves contained twelve individuals, two of whom are estimated to be children and the rest adults. Only three individuals have been able to be gender assessed, of which one is male and two are female. The individuals’ length was not possible to calculate due to lack of bones measurable bones. The analysis of the individuals in the burials showed that multiple skeletal changes affected the individuals such as joint changes, fracture, cut damage and traces of activity. Some of the skeletons have shown survival of trauma, which is an indication of good basic health. But since the majority of individuals do not show any skeletal diseases and died at a young age, according to the osteological paradox, they generally had poor basic health. The skeletal changes that have been found show that the individuals were exposed to some pain, discomfort, stiffness, and strain during their lives. But despite everything, the individuals lived a relatively long life with better health than other individuals both from Gotland and Skåne during the Bronze Age.
32

Radio-labelling as a tool to investigate the absorption and bio-distribution of selected antimalarial drugs / Abraham Johannes Swanepoel

Swanepoel, Abraham Johannes January 2014 (has links)
Previous studies have shown that the formulation of an active pharmaceutical ingredient (API) entrapped in the Pheroid® (Pheroid for simplification) delivery system enhances absorption of the API, suppresses its metabolism, and may contribute to an increase in the quantity of the API present at the site of action. Higher drug levels at the active site should particularly increase the effectiveness of a drug with a narrow therapeutic index and reduce the incidence of the resistance that may otherwise arise if the sub-therapeutic levels of the API are in contact with the site of interest. Two approaches were followed in this study. First, the radioactive tracer molecule 99mTechnetium methylene diphosphonate (99mTc MDP) was used. Intravenously injected 99mTc MDP is an extremely effective bone-seeking radiopharmaceutical used in the diagnosis of bone disorders such as bone metastases in patients. However, if entrapped inside a Pheroid vesicle, it will locate to that site, usually an organ, where the Pheroid vesicles may tend to accumulate. Experiments conducted with 99mTc MDP alone or with Pheroid will therefore establish how efficiently Pheroid vesicles localize and will also indicate the preferred site of localization inside a body. The process would involve the oral administration of 99mTc MDP either alone or with Pheroid, involving an animal model. It would also involve tracking localization to particular organs, blood or other sites. The second approach requires the use of chloroquine (CQ) labeled with carbon-14 (14C-CQ,) to compare absorption of the drug both with and without the Pheroid system. The intention was to compare oral absorption and bio-distribution of 14C-CQ administered either alone or entrapped in the Pheroid system. It was also possible to establish whether the Pheroid affects the biological half-lives of the CQ and residence times of CQ in the different organs of the body. Absorption of free 99mTc MDP (orally adminsistered) through the intestinal tract is negligible but it was anticipated that increased absorption will be observed when 99mTc MDP was entrapped in the Pheroid system. In the 99mTc MDP study, different routes of administration of 99mTc MDP, as well as 99mTc MDP entrapped and not entrapped in the Pheroid system, were investigated. The Sprague Dawley rat was used as animal model. Rats were divided into three groups of four rats each for the first part of the study. In the first group, only 99mTc MDP was injected intravenously in order to establish natural distribution of the 99mTc MDP. For the second group, 99mTc MDP was administered orally in order to establish whether there was any absorption through the intestinal tract. In the third group, the 99mTc MDP was entrapped in Pheroid vesicles and this formulation was administered orally in order to establish whether the Pheroid system enhanced oral absorption. The animals were sacrificed four hours after administration and organs were harvested and were counted for radioactivity to determine the percentage of injected/administrated dose in each organ. After oral administration, the Pheroid system was found to have facilitated absorption of 99mTc MDP through the intestinal tract into the blood. 99mTc MDP concentrations in the femur, although lower, were still comparable with that observed after intravenous administration of 99mTc MDP in the absence of Pheroid. Thus, overall, excellent absorption of the Pheroid entrapped 99mTc MDP through the intestinal tract was seen in contrast to little or zero absorption of the compound in the reference formulations. The half-life of the radio-labelled compound in the blood was prolonged after oral administration owing to the Pheroid. To investigate the bio-distribution of radioactive chloroquine (14C-CQ) Sprague Dawley rats were divided into two groups of four rats each. In the first group, 14C-CQ in deionised (DI) water was administered orally, and in the second group 14C-CQ entrapped in Pheroid vesicles was administered, also orally. The animals were sacrificed one, two and four hours after administration and subjected to comprehensive macroscopic inspection. All the organs were harvested and radioactivity was determined with liquid scintillation after applicable sample preparation. The Pheroid system produced much higher organ and blood concentrations of 14C-CQ and enhanced residence times within the organs and blood in comparison with that of 14C-CQ administered alone. Commercial applications of these results are possible, as a number of radiopharmaceutical products can presently be administered only intravenously. The added potential of these new Pheroid formulations could be of significance in the treatment of malaria, as chloroquine is inexpensive and widely available. Another point of interest is that the use of these formulations may enable micromolar drug concentrations to be achieved using drug dosage regimes that usually produce only nanomolar levels. However, safety aspects would have to be carefully monitored. / PhD (Pharmaceutics), North-West University, Potchefstroom Campus, 2015
33

Radio-labelling as a tool to investigate the absorption and bio-distribution of selected antimalarial drugs / Abraham Johannes Swanepoel

Swanepoel, Abraham Johannes January 2014 (has links)
Previous studies have shown that the formulation of an active pharmaceutical ingredient (API) entrapped in the Pheroid® (Pheroid for simplification) delivery system enhances absorption of the API, suppresses its metabolism, and may contribute to an increase in the quantity of the API present at the site of action. Higher drug levels at the active site should particularly increase the effectiveness of a drug with a narrow therapeutic index and reduce the incidence of the resistance that may otherwise arise if the sub-therapeutic levels of the API are in contact with the site of interest. Two approaches were followed in this study. First, the radioactive tracer molecule 99mTechnetium methylene diphosphonate (99mTc MDP) was used. Intravenously injected 99mTc MDP is an extremely effective bone-seeking radiopharmaceutical used in the diagnosis of bone disorders such as bone metastases in patients. However, if entrapped inside a Pheroid vesicle, it will locate to that site, usually an organ, where the Pheroid vesicles may tend to accumulate. Experiments conducted with 99mTc MDP alone or with Pheroid will therefore establish how efficiently Pheroid vesicles localize and will also indicate the preferred site of localization inside a body. The process would involve the oral administration of 99mTc MDP either alone or with Pheroid, involving an animal model. It would also involve tracking localization to particular organs, blood or other sites. The second approach requires the use of chloroquine (CQ) labeled with carbon-14 (14C-CQ,) to compare absorption of the drug both with and without the Pheroid system. The intention was to compare oral absorption and bio-distribution of 14C-CQ administered either alone or entrapped in the Pheroid system. It was also possible to establish whether the Pheroid affects the biological half-lives of the CQ and residence times of CQ in the different organs of the body. Absorption of free 99mTc MDP (orally adminsistered) through the intestinal tract is negligible but it was anticipated that increased absorption will be observed when 99mTc MDP was entrapped in the Pheroid system. In the 99mTc MDP study, different routes of administration of 99mTc MDP, as well as 99mTc MDP entrapped and not entrapped in the Pheroid system, were investigated. The Sprague Dawley rat was used as animal model. Rats were divided into three groups of four rats each for the first part of the study. In the first group, only 99mTc MDP was injected intravenously in order to establish natural distribution of the 99mTc MDP. For the second group, 99mTc MDP was administered orally in order to establish whether there was any absorption through the intestinal tract. In the third group, the 99mTc MDP was entrapped in Pheroid vesicles and this formulation was administered orally in order to establish whether the Pheroid system enhanced oral absorption. The animals were sacrificed four hours after administration and organs were harvested and were counted for radioactivity to determine the percentage of injected/administrated dose in each organ. After oral administration, the Pheroid system was found to have facilitated absorption of 99mTc MDP through the intestinal tract into the blood. 99mTc MDP concentrations in the femur, although lower, were still comparable with that observed after intravenous administration of 99mTc MDP in the absence of Pheroid. Thus, overall, excellent absorption of the Pheroid entrapped 99mTc MDP through the intestinal tract was seen in contrast to little or zero absorption of the compound in the reference formulations. The half-life of the radio-labelled compound in the blood was prolonged after oral administration owing to the Pheroid. To investigate the bio-distribution of radioactive chloroquine (14C-CQ) Sprague Dawley rats were divided into two groups of four rats each. In the first group, 14C-CQ in deionised (DI) water was administered orally, and in the second group 14C-CQ entrapped in Pheroid vesicles was administered, also orally. The animals were sacrificed one, two and four hours after administration and subjected to comprehensive macroscopic inspection. All the organs were harvested and radioactivity was determined with liquid scintillation after applicable sample preparation. The Pheroid system produced much higher organ and blood concentrations of 14C-CQ and enhanced residence times within the organs and blood in comparison with that of 14C-CQ administered alone. Commercial applications of these results are possible, as a number of radiopharmaceutical products can presently be administered only intravenously. The added potential of these new Pheroid formulations could be of significance in the treatment of malaria, as chloroquine is inexpensive and widely available. Another point of interest is that the use of these formulations may enable micromolar drug concentrations to be achieved using drug dosage regimes that usually produce only nanomolar levels. However, safety aspects would have to be carefully monitored. / PhD (Pharmaceutics), North-West University, Potchefstroom Campus, 2015
34

Caractérisation de la matière organique dissoute d'un site d'eau de surface (fleuve Saint-Laurent) et d'un site d'eau souterraine (aquifère de l'Astien, France) par l'utilisation des isotopes du carbone et des produits d'oxydation de la lignine

Moingt, Matthieu 01 March 2008 (has links) (PDF)
Le cycle de la matière organique à l'échelle continentale reste encore en partie méconnu. Ainsi, le COD a surtout été étudié sous un aspect chimique indifférencié. Des études isotopiques et l'utilisation de biomarqueurs ont permis d'élucider certains aspects de son cycle. La présente étude s'inscrit dans cette perspective. Deux types de milieux distincts, le fleuve Saint-Laurent et l'aquifère de l'Astien (France), ont été examinés. Dans le volet "Saint-Laurent", nous nous sommes intéressés au cycle du carbone organique terrigène (COT) à partir de mesures 13C et 14C du COD et d'une composante réfractaire du COD afin de comprendre l'origine et l'évolution du COT lors de son transit vers l'océan. Dans le second volet, les mêmes approches ont été retenues afin de déterminer la nature, les sources, l'état de dégradation et l'évolution temporelle du COD dans une nappe d'eau souterraine. Nous retenons une origine majoritairement terrigène pour le COD du Saint-Laurent, ainsi que son âge globalement très récent. Cependant, une fraction de ce COD est apparue beaucoup plus ancienne. La présente étude indique que le COD total du système hydrologique du fleuve Saint-Laurent est en majorité constitué de composés organiques facilement biominéralisables et donc potentiellement grands consommateurs d'oxygène dissous. Le COT pourrait donc jouer un rôle plus important qu'estimé aujourd'hui dans l'apparition de conditions hypoxiques dans les estuaires et zones côtières du globe. Dans le système de l'aquifère de l'Astien, les cinétiques relatives de dégradation des composés organiques issus de la macromolécule ligneuse pourraient donner lieu à des applications géochronométriques.
35

Exposure of Caco-2 cells to PFOS and PFOA

Neskovic, Anika January 2007 (has links)
<p>The toxicity of perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) was measured. When Caco-2 cells from human adenocarcinoma are cultivated on a filter a monolayer is formed with properties similar to human duodenum epithelium. The Caco-2 cells grown on filter were exposed to the environmental contaminants PFOS and PFOA. The effects on the Caco-2 epithelium were examined by four different methods: trans-epithelial resistance (TEER), leakage of the intracellular protein lactate dehydrogenase (LDH), 14C-mannitol passage through the epithelium and protein content of the epithelium. TEER and C-mannitol passage show the Caco-2 cellmonolayer integrity, LDH leakage gives information of cytotoxicity and protein content of the epithelium shows cell adhension to the filter.</p><p>In the first study TEER decreased at the highest concentrations of PFOS and PFOA (1Mm). The 14C-mannitol passage increased at the highest PFOS concentration. No cytotoxicity was shown and protein-loss was not observed. The second study with PFOS doses of 0, 1, 10, 100 and 500µM and 1 and 10mM showed that the effect of PFOS on TEER was dose-dependent. The 14C-mannitol passage was very high at the highest PFOS-concentration (10mM) and a dose-response was indicated. No cytotoxicity was demonstrated and protein-quantity was not affected. In the third study it was demonstrated that the toxicity of PFOS did not depend on the different concentrations of the oil-emulsion used to dissolve PFOS and PFOA.</p>
36

14C年代から暦年代への較正に関連する諸問題

YOSHIMITSU, Takahiro, NAGAYA, Kentaro, MIYAKE, Fusa, MASUDA, Kimiaki, NAKAMURA, Toshio, 吉光, 貴裕, 永治, 健太朗, 三宅, 芙沙, 増田, 公明, 中村, 俊夫 03 1900 (has links)
名古屋大学年代測定総合研究センターシンポジウム報告
37

ベルリン・アジア美術館所蔵のキジル将来壁画の放射性炭素年代

NAKAMURA, Toshio, SATO, Ichiro, TANIGUCHI, Yoko, NAKAGAWARA, Ikuko, 中村, 俊夫, 佐藤, 一郎, 谷口, 陽子, 中川原, 育子 03 1900 (has links)
名古屋大学年代測定総合研究センターシンポジウム報告
38

JAEA-AMS-MUTSUにおける14C測定の現状

Seki, T, Kinoshita, N, Kabuto, S, Tanaka, T, 関, 武雄, 木下, 尚喜, 甲, 昭二, 田中, 孝幸 03 1900 (has links)
第23回名古屋大学年代測定総合研究センターシンポジウム平成22(2010)年度報告
39

モンゴル・フブスグル湖湖沼堆積物のPost-IR IRSL年代測定

柏谷, 健二, Duller, Geoff, Kashiwaya, Kenji, Nakamura, Toshio, Arai, Shoji, Hasebe, Noriko, Ito, Kazumi, 中村, 俊夫, 荒井, 章司, 長谷部, 徳子, 伊藤, 一充 03 1900 (has links)
名古屋大学年代測定総合研究センターシンポジウム報告
40

Using lignin biomarkers and 14C, of both river DOC and POC, and permafrost soils, to characterize the impacts of climate warming and permafrost degradation on the organic carbon budget of the Hudson Bay, Canada

Godin, Pamela 08 January 2015 (has links)
This study looks at characterizing the terrigenous OC sources, like permafrost, of POC and DOC through 17 rivers and six soils of the Hudson Bay (HB) using lignin biomarkers, and Δ14C. Our findings show the dominance of the OC flux (89%) from the southwest Hudson Bay Rivers, especially from DOC (93%), shedding light on the sources and fate of OC in HB sediments. With warming, organic cryosols, with high OC content in the Cz horizon, have the potential to release as much as 1.5 gOC/m2 for every cm increase in active layer depth. The [Ad/Al] ratios, when combined with 14C ages of DOM, show that older SOC is being released in some rivers and is fresher than expected due to its preservation within permafrost. S/V and C/V ratios, are well correlated to latitude in DOM, reflecting the vegetation in their drainage basins and can be used to indicate OC sources.

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