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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.
381

REAL-TIME VISUALIZATION OF FIBER/MATRIX INTERFACIAL DEBONDING BEHAVIOR

Jou-Mei Chu (5929589) 03 January 2019 (has links)
<div>The rate effect of fiber-matrix interfacial debonding behavior of SC-15 epoxy and various fiber reinforcements was studied via in-situ visualization of the debonding event. Special focus has been placed on the dynamic transverse debonding of single fiber reinforced polymer composites. In this study, the debonding force history, debonding initiation, debonding crack velocity, and crack geometry were characterized using a quasi-static load frame and a modified tension Kolsky bar at loading velocities of 0.25 mm/s and 2.5 m/s. Cruciform-shaped specimens were used for interfacial transverse debonding between SC-15 epoxy matrix and various fiber reinforcements including S-2 glass, Kevlar® KM2, and tungsten fiber materials. The load history and high-speed images of the debonding event were simultaneously recorded. A major increase was observed for the average peak debonding force and a minor increase was observed for the average crack velocity with increasing loading velocity. The crack geometry of the cruciform specimens under both loading velocities was also tracked. Scanning electron microscopy of the recovered specimens revealed the debonding direction along the fiber-matrix interface through angled patterns on the failure surface.</div><div><br></div><div>The dynamic shear debonding of single fiber reinforced plastic composites were also studied via the real-time visualization with the fiber pull-out method. The interfacial shear debonding was studied between SC-15 epoxy and fiber reinforcements including S-2 glass, tungsten, steel, and carbon composite Z-pin fiber materials at 2.5 m/s and 5.0 m/s. Both S-2 glass fiber and Z-pin experienced catastrophic interfacial debonding whereas tungsten and steel wire experienced both catastrophic debonding and stick-slip behavior. Scanning electron microscope imaging of recovered epoxy beads revealed a snap-back behavior around the meniscus region of the bead for S-2 glass, tungsten, and steel fiber materials at 5.0 m/s whereas those at 2.5 m/s exhibited no snap-back behavior.</div>
382

Zebrafish as a model to study genes associated with neurodevelopmental disorders

Gostić, Monika January 2018 (has links)
Dyslexia is a neurodevelopmental disorder that affects between 5% and 12% of school-aged children. Individuals with dyslexia have difficulties in learning to read despite normal IQ levels and adequate socio-economical and educational opportunities. Dyslexia has a strong genetic component, but only a few candidate genes have been characterized to date. The KIAA0319 gene is a strong dyslexia candidate found to be associated with dyslexia in independent studies. The KIAA0319 genetic variants associated with dyslexia reside in a regulatory region. Studies in rat suggested that this gene is required for neuronal migration during early cortex formation. The KIAA0319-like (KIAA0319L) is a KIAA0319 homolog in structure and has recently been shown to play a role in dyslexia. I used zebrafish as a model organism both to study the effects of non-coding variants and to characterise kiaa0319 gene function. I used Gateway Tol2 technology to study the role of regulatory sequences. While these experiments led to inconclusive results, they highlighted some of the challenges but also the feasibility of using zebrafish as model organism to study genetic associations. In parallel, I studied the kiaa0319 function with knockout and knockdown experiments. Additionally, I conducted a detailed gene expression analysis with different in situ hybridisation protocols showing kiaa0319 ubiquitous expression in the whole embryo before 12 hours post fertilisation, with later specification to the eyes, brain, otic vesicle and notochord. Additionally, I have tested for the expression of kiaa0319l and showed similar expression pattern to the kiaa0319, but with significantly lower expression of kiaa0319l in zebrafish notochord. My data show, for the first time, that kiaa0319 has stage-specific expression in the brain and notochord during zebrafish early development, suggesting kiaa0319 specific role in the development of these structures. These results are in line with recent mouse studies. With this project I support the idea of kiaa0319 role being extended beyond the brain function and propose a role for kiaa03019 in the visual system and in the notochord.
383

Expressão das proteinas bcl-2, c-erbB-2 e p53 no tecido não-neoplasico, no carcinoma ductal in situ e no carcinoma invasivo da mesma mama

Menezes, Marcus Vinicius Martins de 09 November 2018 (has links)
Orientadores : Luiz Carlos Zeferino, Maria Salete Costa Gurgel / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-11-09T15:57:30Z (GMT). No. of bitstreams: 1 Menezes_MarcusViniciusMartinsde_M.pdf: 4462397 bytes, checksum: 19e649c8f79ccdfab39e8019f7d69049 (MD5) Previous issue date: 2002 / Resumo: Este estudo teve como objetivo avaliar a associação entre a expressão das proteínas bcl-2, c-erbB-2 e p53 com o tecido mamário não-neoplásico, o carcinoma ductal in situ e o carcinoma invasivo da mesma mama, através da imuno-histoquímica, e verificar se há um padrão de variação identificável da expressão destas proteínas com a gravidade das lesões. Foram incluídas 56 mulheres que apresentaram na mesma mama carcinoma invasivo associado com carcinoma in situ. Foram utilizados anticorpos monoclocais específicos para bcl-2 (MxH, clone 124, DAKO, código M0887-1, diluição 1:40), c-erbB-2 (RxH, DAKO, código A0485-1, diluição 1 :300) e p53 (MxH, D0-7, DAKO, código M7001-1, diluição 1:100). Foi considerado como expressão positiva quando pelo menos 1% das células corou. A prevalência da expressão da proteína bcl-2 foi de 98%, 75% e 64%, respectivamente, no tecido não-neoplásico, carcinoma in situ e carcinoma invasivo e estas diferenças foram estatisticamente significantes. O odds ratio mostrou que a magnitude destas diferenças foi maior entre o tecido não-neoplásico e o carcinoma in situ. Não houve expressão da proteína c-erbB-2 no tecido não-neoplásico e a prevalência da expressão foi de 68% e 61%, respectivamente, para o carcinoma in situ e carcinoma invasivo. A diferença observada entre o tecido não-neoplásico e carcinoma in situ foi estatisticamente significante. A prevalência da expressão da proteína p53 foi de 2%, 18% e 16%, respectivamente, no tecido não-neoplásico, carcinoma in situ carcinoma invasivo e estas diferenças foram estatisticamente significantes entre os dois primeiros componentes. A expressão da proteína bcl-2 foi mais freqüente no carcinoma in situ do subtipo não-comedo e grau nuclear 1 ou 2 e no carcinoma invasivo grau nuclear 1 ou 2. A expressão da proteína c-erbB-2 foi mais freqüente no carcinoma in situ grau nuclear 3 e a expressão da proteína p53 foi mais freqüente no carcinoma invasivo grau nuclear 3. Sessenta e quatro porcento das mulheres apresentaram expressão da proteína bcl-2 nos três componentes e 23% apresentaram apenas no componente não-neoplásico. Sessenta e um porcento das mulheres apresentaram expressão da proteína cerbB- 2 apenas nos componentes carcinoma in situ e carcinoma invasivo e 32% não apresentaram expressão em nenhum dos componentes. Setenta e oito porcento das mulheres não apresentaram expressão da proteína p53 em nenhum dos componentes e 14% apresentaram apenas nos componentes in situe invasivo. Os resultados deste estudo permitem inferir que os genes Bcl-2, C-erbB-2 e P53 estão envolvidos nas fases mais iniciais da carcinogênese mamária, ou seja, na transformação do dueto não-neoplásico em carcinoma in situ. Uma vez instalada a lesão intra-epitelial, a progressão para a forma invasiva dependeria de outros genes / Abstract: The present study aims to evaluate the association among the expression of the proteins bcl2, c-erbB-2 and p53 and the non-neoplasic mammary tissue, the ductal carcinoma in situ and the invasive carcinoma of the same breast using the immunohistochemical technique. Through this evaluation it aims to find out if there is an identifiable pattern of variation of the expression of these proteins with the gravity of the lesions. Fifty six women were included in this study and ali of them had, in the same breast, the association between invasive carcinoma and carcinoma in situ. lt has been used specific monoclonal antibodies for bcl-2 (MxH, clone 124, DAKO, code M0887-1, dilution 1:40), cerbB- 2 (RxH, DAKO, code A0485-1, dilution 1:300) and p53 (MxH, D0-7, DAKO, code M7001-1, dilution 1:100). Positive expression has been considered when, at least 1% of the cells dyed. The prevalence of the expression of the protein bcl-2 was 98%, 75% and 64%, respectively in the non-neoplasic tissue, carcinoma in situ and invasive carcinoma and these differences were statistically significant. The odds ratio confirmed that the magnitude of these differences was higher between the non-neoplasic tissue and the carcinoma in situ. There was no expression of the protein c-erbB-2 in the non-neoplasic tissue and the prevalence of expression of this protein was 68% and 61%, respectively in carcinoma in situ and invasive carcinoma. The difference found between the non-neoplasic tissue and the carcinoma in situ was statistically significant. The prevalence of expression of protein p-53 was 2%, 18% and 16%, respectively in the non-neoplasic tissue, carcinoma in situ and invasive carcinoma and these differences were statistically significant between the two formers only. The expression of the protein bcl-2 was more frequent in carcinoma in situ noncomedo type, nuclear degrees 1 or 2 and in invasive carcinoma nuclear degrees 1 or 2. The expression of protein c-erbB-2 was more frequent in carcinoma in situ nuclear degree 3 and the expression of protein p53 was more frequent in invasive carcinoma nuclear degree 3. Sixty four per cent of women studied showed expression of protein bcl-2 in ali three components and 23% of women showed it only in the non-neoplasic component. Sixty one per cent of women showed expression of protein c-erbB-2 only in carcinoma in situ and invasive carcinoma and 32% did not show expression at ali. Sixty eight per cent of women did not show expression of protein p53 in none of the components and 14% showed it only in the components 'in situ' and 'invasive'. The results of the present study allow us to conclude that the genes Bcl-2, C-erbB-2 and P53 are linked to the initial stages of mammary carcinogenesis, in other words, they are linked to the transformation of the non-neoplasic duct in carcinoma in situ. Once the intra-epithelial lesion has started, the progression to invasive form would depend on other genes / Mestrado / Tocoginecologia / Mestre em Tocoginecologia
384

Mecanismos de evolução cromossômica e diferenciação cariotípica em espécies das subfamílias Hylinae (tribos Cophomantini e Lophiohylini) e Phyllomedusinae (Hylidae, Anura, Amphibia)

Gruber, Simone Lilian [UNESP] 14 February 2013 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:55Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-02-14Bitstream added on 2014-06-13T19:40:29Z : No. of bitstreams: 1 gruber_sl_dr_rcla_parcial.pdf: 155184 bytes, checksum: df5017c0c5ab7c0586283ad815f95539 (MD5) Bitstreams deleted on 2015-07-02T12:36:06Z: gruber_sl_dr_rcla_parcial.pdf,. Added 1 bitstream(s) on 2015-07-02T12:37:30Z : No. of bitstreams: 1 000713629_20180214.pdf: 142653 bytes, checksum: 303de0bbf7c0cc98840a1feafcac3291 (MD5) Bitstreams deleted on 2018-02-16T12:28:24Z: 000713629_20180214.pdf,. Added 1 bitstream(s) on 2018-02-16T12:29:08Z : No. of bitstreams: 1 000713629.pdf: 1305461 bytes, checksum: fc93fa24bfaab78fbbbdb8eb677acfba (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A classe Amphibia, especialmente a família Hylidae, passou por extensas modificações na taxonomia e sistemática, realizadas com base, principalmente, em dados moleculares, mas quase nenhuma contribuição das informações citogenéticas. Os hilídeos são os anuros mais abundantes em número de espécies, porém, a maioria delas foi sequer cariotipada e grande parte das informações disponíveis na literatura está restrita apenas ao número e morfologia dos cromossomos. No presente trabalho, foram cariotipadas 28 espécies da subfamília Hylinae, sendo da tribo Cophomantini Aplastodiscus arildae, A. callipygius, A. eugenioi, A. leucopygius, A. perviridis, Hypsiboas aff. polytaenius, Hypsiboas sp. aff. albopunctatus, H. albomarginatus, H. albopunctatus, H. bakeri, H. caingua, H. caipora, H. crepitans, H. faber, H. latistriatus, H. lundii, H. pardalis, H. polytaenius, H. prasinus, H. raniceps e H. semilineatus; da tribo Lophiohylini, as espécies Aparasphenodon bokermanni, Itapotihyla langsdorffii, Phyllodytes edelmoi, P. luteolus, Trachycephalus sp., T. mesophaeus e T. typhonius; e da subfamília Phyllomedusinae, duas espécies, Phyllomedusa distincta e P. tetraploidea, bem como seus híbridos triploides. A maioria das espécies da subfamília Hylinae compartilha cariótipo 2n=24, FN=48, bandas C majoritariamente centroméricas e RON em cromossomos pequenos do par 11 em Cophomantini e do par 10 em Lophiohylini. As exceções são as do gênero Phyllodytes, da tribo Lophyohylini, cujas espécies têm 2n=22, FN=44 e RON no par 2, e as do gênero Aplastodiscus, da tribo Cophomantini, cujas espécies têm diferentes números cromossômicos de 2n=24, 2n=22, 2n=20 e 2n=18, mas compartilham o mesmo padrão de bandamento C e o mesmo par marcador de RON. As bandas de replicação por incorporação de BrdU... / The Amphibia class, especially the family Hylidae, went through extensive changes in taxonomy and systematics, based mainly on molecular data, but with almost no contribution of cytogenetic information. This family is the most speciose among the anurans, however, the great majority of the species was never karyotyped, and most of the cytogenetic information on hylids available in the literature is restricted to the number and morphology of the chromosomes. In the present work we karyotyped 28 representatives of the subfamily Hylinae, belonging to the tribe Cophomantini the species Aplastodiscus arildae, A. callipygius, A. eugenioi, A. leucopygius, A. perviridis, Hypsiboas aff. polytaenius, Hypsiboas sp. aff. albopunctatus, H. albomarginatus, H. albopunctatus, H. bakeri, H. caingua, H. caipora, H. crepitans, H. faber, H. latistriatus, H. lundii, H. pardalis, H. polytaenius, H. prasinus, H. raniceps e H. semilineatus; to the tribe Lophiohylini the species Aparasphenodon bokermanni, Itapotihyla langsdorffii, Phyllodytes edelmoi, P. luteolus, Trachycephalus sp., T. mesophaeus e T. typhonius; and two species of the subfamily Phyllomedusinae, Phyllomedusa distincta and P. tetraploidea, as well as their triploid hybrids. Most species of the subfamily Hylinae share the same karyotype with 2n=24, FN=48, C bands with predominantly centromeric distribution, and NOR located on small chromosomes belonging to the pair 11 in Cophomantini and to the pair 10 in Lophiohylini. The exceptions are the genus Phyllodytes, from the tribe Lophyohylini, whose species have 2n=22, FN=44 and NOR in the pair 2, and the genus Aplastodiscus, from the tribe Cophomantini, whose species have different chromosome numbers of 2n=24, 2n=22, 2n=20, Abstract and 2n=18, but sharing the same C-banding pattern and the same pair of NOR marker... (Complete abstract click electronic access below)
385

Efeitos da salinomicina no consumo, degradação no rúmen e in vitro, taxas de produção de gases e fermentação in vitro de dietas compostas por feno de capim coast cross (Cynodon dactylon) e sal proteinado / Effects of salinomycin on dry matter intake , in situ and in vitro degradability , rates of gas production and fermentation of cynodon (Cynodon dactylon) hay supplemented with proteic salt

Olga Lurdes Jossias Faftine 17 February 2006 (has links)
Este trabalho pretende avaliar o efeito da salinomicina no consumo de feno coast cross e sal proteinado, na digestibilidade total, ruminal in situ e in vitro, taxas de produção de gases e taxas de fermentação. Para a avaliação da digestibilidade e degradabilidade in situ foram utilizados 4 novilhos Holandeses com peso médio de 350 kg ± 43 kg. O delineamento experimental utilizado foi o quadrado latino com 4x4. No ensaio in vitro foram utilizados 4 substratos *8 inóculos *2 corridas com delineamento em blocos e arranjo fatorial. Os tratamentos estudados foram: 0; 0,1; 0,2; 0,3 mg de salinomicina /kg de peso vivo. Não foram encontradas diferenças significativas (p>0,05) no consumo de MS(1,92; 1,73; 1,60; 1,63 %PV), digestibilidade aparente da MS (81,79; 80,32; 80,32 e 80,49), na degradação in situ da MS (52; 51,25; 49,20 e 51,38) e na degradação in vitro da MS (45,31; 45,64; 45,77; 45,03) entre os vários tratamentos. Os únicos parâmetros onde foram identificadas alterações significativas entre os tratamentos foram no volume final de gases in vitro e nas curvas de taxas de fermentação. Os valores encontrados de para o volume final de gases foi de 231,8; 204; 168 e 157,78 ml /g de MS para a dose de 0; 0,1; 0,2 e 0,3 mg de salinomicina/ kg de PV, respectivamente. O tratamento 3 foi o que teve menores perdas de energia. / This experiment was conducted to evaluate the effect of graded levels of salinomycin on feed intake, apparent di estibility, gas production and fermentation rate, degradability in situ and in vitro of cynodon hay supplemented with proteic salt with 0, 0.1, 0.2 and 0,3mg of salynomicin per kg LW. Intake , digestibility and degradabilty studies were analysed as a latine square design 4x4 and in vitro trials followed the block randomized design with a two factors (inocula and substrate). No differences (p>)0,05) were found between the treatments for DM intake (1.92, 1.73, 1.60, 1.63 per % LW), DM digestibility (81.79, 80.32, 80.32 and 80.49), DM in situ degradability (52, 51.25, 49.20 and 51.38) and in vitro DM degradability (45.31, 45.64, 45.77 and 51.38). Differences between treatments were found only for potencial gas production in vitro (231.8, 204, 168 and 157.78 ml/g DM) for 0, 0.1, 0.2 and 0,3 mg of salinomycin/kg LW. Therefore, wasting energy was minimized at treatment 3.
386

In-situ production of electrically conductive polyaniline fibres from polymer blends

Cruz-Estrada, Ricardo Herbe January 2002 (has links)
Polymers and polymer-based composite materials with electro-conductive properties, respectively, are materials with several potential applications. New materials are being offered in every area and novel products are constantly being introduced. Among these new materials, composites made of electro-conductive monofilaments and insulating polymers are nowadays being used as antistatic materials in the carpets and textiles industries. One promising approach for the manufacture of this kind of material is to generate the electrically conductive fibres in-situ, that is, during the actual forming process of the component. The main objective of this project was to establish the feasibility of producing electrically conductive polyaniline (PANI) fibres within a suitable polymer matrix by means of the development of a suitable processing strategy, which allows the fabrication of an anisotropically conducting composite. It is remarkable, however, that layered structures of the conducting filler were also formed within the matrix material. The latter morphology, particularly observed in compression moulded specimens of a specific polymer system, was also in good agreement with that inferred by means of a mathematical model. Experimentation was carried out with three different PANI conductive complexes (PANIPOLTM). They were initially characterised, which assisted in the identification of the most suitable material to be deformed into fibres. Preliminary processing was carried out with the selected PANIPOLTM complex, which was blended with polystyrene-polybutadiene-polystyrene (SBS), low density polyethylene (LDPE) and polypropylene (PP), respectively. The resultant blends were formed by ram extrusion, using a capillary die, to induce the deformation of the conducting phase into fibres. The morphological analysis performed on the extrudates suggested that the most suitable polymer matrix was SBS. Further experimentation was carried out with the polymer system selected. The relationships between the content of conductive complex in the composites and their electrical conductivity and microstructure were established. The blends were compression moulded and they displayed a morphology of layered domains of the conducting phase within the SBS matrix. The behaviour of the conductivity with respect to the PANIPOLTM complex in the compression moulded blends was found to be characteristic of a percolating system with a threshold as low as 5 weight percent of the conducting filler in the blends. The morphological analysis performed on the extruded blends suggested that the conducting phase was deformed into elongated domains, aligned parallel to the extrusion direction, which in some cases displayed a considerable degree of continuity and uniformity. The level of electrical conductivity in the extrudates was considerably lower than that of their corresponding non-extruded blends. This was attributed to a lack of continuity in the conducting elongated domains produced in-situ within the SBS matrix. Percolation theory and a generalisation of effective media theories were used to model the behaviour of the conductivity with respect to the content of PANIPOLTM in the compression moulded blends. Both approaches yielded similar values for the critical parameters, which were also in good agreement with the percolation threshold experimentally observed. The results of the modelling suggested that, at the percolation threshold, the morphology of the composite may consists of aggregates of flattened polyaniline particles forming very long layered structures within the SBS matrix, which is in agreement with the results of the morphological analysis.
387

Plane of Energy Nutrition on Blood Metabolites, Milk Production and Lamb Growth in Friesian Sheep

Jensen, Rebekah Paige 01 June 2018 (has links)
Small ruminant species are utilized for their diverse products including meat, dairy products, and wool. Effective and humane management are essential to maintain high production rates and comfortable animals. To attain this objective, managers needs to have an extensive knowledge of husbandry techniques, understanding of physiological processes, and familiarity with nutritional requirements. We examined the effects of varying feed components on two different ruminal species. In Chapter 1, we conducted a study to evaluate"¯the effects"¯of a low metabolizable energy (LME) and high metabolizable energy (HME) diet on twenty-two Friesian/Lacuane"¯cross ewes and lamb nutritional status."¯Effects on milk production during early lactation stages"¯and the growth of the neonatal lambs were also investigated. We anticipate energy levels will have an effect on milk production and lamb growth. Our results indicate that ewes on the LME diet produced more milk with higher concentrations of fat though this group maintained lower body condition. We concluded that neither the HME nor the LME diet met the needs of the sheep due to the shift in nutrient partitioning towards milk production rather than allocating nutrients to maintaining both body condition and milk production. Limited energy requirements are further evidenced by the decline in back fat (BF) for both the HME and LME groups for the duration of the study. We determined the degradation parameters of grass hay supplemented with soybean meal (SBM) and the effects of SBM on compartment 1 (C1) ammonia and volatile fatty acid (VFA) concentrations in alpacas. Our findings show that the degradation rate was not different for dry matter (DM), but it was for crude protein (CP) (P<0.05). With this data it can be concluded that SBM can be a CP supplement when the diet is insufficient to improve microbial yield. It should be noted that care should be taken to avoid causing a protein-energy imbalance. The results of these two studies indicate shifts in nutrients availability and changes in feeding strategies can affect both the health of the animal and their subsequent offspring.
388

Charakterisierung der pathogenetisch-relevanten Rolle von SF1 beim Nebennierenrindenkarzinom / Characterisation of the pathogenetic-relevant role of SF1 in adrenocortical carcinoma

Schmull, Sebastian January 2011 (has links) (PDF)
Tumore der Nebennieren stellen häufige Tumore dar, welche bei mindestens 3 % der Population über 50-Jähriger vorkommen. Im Gegensatz dazu ist das Nebennierenrindenkarzinom mit einer Inzidenz von 1-2 Einwohner pro Million ein sehr seltener Tumor. Da seine Prognose allerdings ungünstig, und diese maßgeblich davon abhängt wie fortgeschritten der Tumor bei Diagnosestellung ist, ist es wichtig, dass die richtige Diagnose frühzeitig gestellt wird. Bis heute ist kein zuverlässiger immunhistochemischer Nebennierenrindenkarzinom-spezifischer Marker etabliert um das Nebennierenrindenkarzinom von anderen retroperitonealen Tumoren zu differenzieren. Sasano et al. schlug bereits 1995 erstmalig den Transkriptionsfaktor Steroidogenic Factor 1 (SF1) als Marker zur Differenzierung von Nebennierenrinden- und Nicht-Nebennierenrindentumoren vor. Allerdings wurde die diagnostische Wertigkeit bisher nur in sehr kleinen Fallserien mit insgesamt nur 17 Nebennierenrindenkarzinomen untersucht. In der vorliegenden Arbeit wurde die SF1 Protein-Expression bei 163 Nebennierenrindenkarzinomen, 52 Nebennierenrinden-Adenomen, 12 normalen steroidogenen Geweben (6 Nebennieren und 6 Ovare), sowie 73 Nicht-Steroidtumoren immunhistochemisch untersucht. Hierbei zeigte sich, das SF1 bei 158 von 161 evaluierbaren Nebennierenrindenkarzinomen und bei allen Proben von normalen und gutartigen Geweben (n=64) nachweisbar war. Im Gegensatz dazu war keine der 73 Nicht-Steroidgeweben SF1 positiv, so dass die diagnostische Genauigkeit extrem gut ist (Sensitivität: 98.6 %, Spezifität: 100 %, positive und negative predictive value jeweils 100 % und 97.3 %). In einem zweiten Schritt wurde untersucht ob die Protein-Expression von SF1 beim Nebennierenrindenkarzinom auch prognostische Bedeutung hat. Hierbei zeigte sich, dass Patienten mit Tumoren mit starker SF1 Färbung (30 %) ein deutlich schlechteres tumorstadium-adjustiertes Rezidiffreies- und Gesamt-Überleben haben als Patienten mit geringer SF1 Expression (hazard ratio: 2.45). Zusätzlich zu den immunhistochemischen Untersuchungen wurden FISH Analysen durchgeführt. Hierbei zeigte sich allerdings keine signifikante Korrelation zwischen SF1 Gendosis und der SF1 Protein-Expression, so dass zu vermuten ist, dass SF1 maßgeblich auf Transkriptions- und Translationsebene reguliert wird. In einem Versuch diese Frage zu beantworten wurden zwei mutmaßliche SF1 Interaktionspartner, FATE1 und DAX1, genauer immunhistochemisch untersucht. Hierbei wurde deutlich, dass FATE1 bei 62 von 141 evaluierbaren Nebenierenrindenkarzinomen und 12 von 62 normalen und gutartigen Geweben nachweisbar war. Im Gegensatz hierzu waren alle 9 Nicht-Steroidgewebe FATE1 negativ. Dies zeigt, das FATE1 nicht zur Diagnostik nutzbar ist (Sensitivität: 61 %, Spezifität: 100 %, positive und negative predictive value 100 % bzw. 14 %). Die DAX1 Analyse zeigte, dass alle 20 normalen und gutartigen Gewebe eine positive DAX1 Färbereaktion zeigten. Von 126 Nebennierenrindenkarzinomen waren 71 DAX1 positiv. Von den 8 untersuchten Nicht-Steroidgeweben waren 6 DAX1 positiv. Diese Ergebnisse belegen, dass auch DAX1 keine diagnostische Genauigkeit besitzt (Sensitivität: 56 %, Spezifität: 25 %, positive und negative predictive value 92 % bzw. 4 %). Die Untersuchung der prognostischen Fähigkeiten von FATE1 und DAX1 zeigte, dass Patienten mit Tumoren mit starker FATE1 Färbung (39 %) ein schlechteres tumorstadium-adjustiertes Gesamt- aber nicht Rezidiffreies-Überleben haben als Patienten mit niedriger FATE1 Protein-Expression (hazard ratio: 2.01). Weiterhin wurde deutlich, dass DAX1 keine deutlichen prognostischen Fähigkeiten besitzt. Zusammenfassend läßt sich aus der vorliegenden Arbeit folgern, das SF1 aktuell der beste diagnostische Marker zur Diagnose von Tumoren der Nebennierenrinde ist und damit Eingang in die histopathologische Routine-Diagnostik von Nebennierentumoren finden wird. Zusätzlich ist die SF1 Expression ein sehr guter prognostischer Marker beim Nebennierenrindenkarzinom, wobei sich die prognostische Aussage durch zusätzliche Färbung von FATE1 und DAX1 nur unwesentlich verbessern läßt. / Adrenal tumors are common tumors which are present in at least 3 % in the human population over their 5th decade. However, adrenocortical carcinoma (ACC) is a rare malignancy which shows an approximate anual incidence of 1-2 per million. Prognosis of ACC is generally poor and depends strongly on the tumor stage. Thus, early and correct diagnosis is important. Until now, no reliable immunohistochemical ACC-specific marker has been established for its differentiation from other retroperitoneal tumors. Already in 1995, Sasano et al. suggested the transcription factor Steroidogenic Factor 1 (SF1) as useful marker for differentiation of adrenocortical and non-adrenocortical tumors. Up to now, SF1's value as diagnostic marker for ACC was investigated only in small series of in a total of 17 samples. In our work, SF1 expression was investigated by immunohistochemistry in 163 ACC, 52 adrenocortical adenomas, 12 normal steroidogenic tissues (6 adrenal glands and 6 ovaries), as well as 73 non-steroidogenic tumors. SF1 protein expression was shown in 158 of a total of 161 evaluable ACC, as well as all normal and benign steroidogenic tissues. In contrast, no SF1 protein was detectable in the non-steroidogenic tumors. Thus, SF1 protein expression is a highly specific diagnostic tool (sensitivity: 98.6 %, specificity: 100 %, positive and negative predictive value: 100 % and 97.3 %, respectively). In a second step, SF1 protein expression was investigated as a prognostic tool in ACC. As shown by us, ACCs presenting strong SF1 immunoreactivity (30 %) showed a strong correlation with overall and recurrence-free patients survival than ACCs presenting low SF1 protein expression (hazard ratio: 2.45). Moreover, FISH analyses were performed which revealed no significant correlation of SF1 gene dosis and SF1 protein expression, suggesting a regulatory mechanism at transcriptional and translational level. To investigate the hypothesis, we investigated two putative interaction partners of SF1, namely FATE1 and DAX1 protein, by immunohistochemistry. FATE1 protein was expressed in 62 of a total of 141 evaluable ACC as well as 12 of a total of 62 normal and benign steroidogenic tissues. In contrast, all non-steroidogenic tissues were FATE1 negative (n=9). Thus, FATE1 is no valuable diagnostic tool (sensitivity: 61 %, specificity: 100 %, positive and negative predictive value: 100 % and 14 %, respectively). DAX1 immunohistochemistry showed that all normal and benign steroidogenic tissues (n=20) were DAX1 positive as well as 71 of a total of 126 ACC samples. Furthermore, 6 out of a total of 8 non-steroidogenic tissues stained DAX1 positive, showing that DAX1 protein is no diagnostic tool (sensitivity: 50 %, specificity: 25 %, positive and negative predictive value: 92 % and 4 %, respectively). Investigation of the prognostic value of FATE1 and DAX1 revealed that patients with tumors characterized by strong FATE1 immunoreactivity (39 %) had a worse outcome in overall but not recurrence-free survival than patients showing low FATE1 expression (hazard ratio: 2.01). DAX1 protein expression has no prognostic value in ACC. In summary, we showed that SF1 is currently the best available diagnostic marker for differentiation of adrenocortical tumors from other retroperitoneal tumors, and that it will be suitable for histopathological diagnostic routine. Furthermore, SF1 expression is a well-suited prognostical tool in adrenocortical carcinoma which is only marginally enhanced by subsequent staining of FATE1 and DAX1 protein.
389

SYNTHESIS, AND STRUCTURAL, ELECTROCHEMICAL, AND MAGNETIC PROPERTY CHARACTERIZATION OF PROMISING ELECTRODE MATERIALS FOR LITHIUM-ION BATTERIES AND SODIUM-ION BATTERIES

Han, Ruixin 01 January 2018 (has links)
Iron oxides, have been widely studied as promising anode materials in lithium-ion batteries (LIBs) for their high capacity (≈ 1000 mA h g-1 for Fe2O3 and Fe3O4,), non-toxicity, and low cost. In this work, β-FeOOH has been evaluated within a LIB half-cell showing an excellent capacity of ≈ 1500 mA h g-1 , superior to Fe2O3 or Fe3O4. Reaction mechanism has been proposed with the assistance of X-ray photoelectron spectroscopy (XPS). Various magnetic properties have been suggested for β-FeOOH such as superparamagnetism, antiferromagnetism and complex magnetism, for which, size of the material is believed to play a critical role. Here, we present a size-controlled synthesis of β-FeOOH nanorods. Co-existing superparamagnetism and antiferromagnetism have been revealed in β-FeOOH by using a Physical Property Measurement System (PPMS). Compared with the high price of lithium in LIBs, sodium-ion batteries (SIBs) have attracted increasing attentions for lower cost. Recent studies have reported Na0.44MnO2 to be a promising candidate for cathode material of SIBs. This thesis has approached a novel solid-state synthesis of Na0.44MnO2 whiskers and a nano-scaled open cell for in situ TEM study. Preliminary results show the first-stage fabrication of the cell on a biasing protochip.
390

Assessing diurnal and seasonal nitrate behavior in large rivers using Nitratax in-situ sensors

Bark, Candice Lynn 01 December 2010 (has links)
The long-term study for the environmental-hydrologic observatory in Pool 16 of the Mississippi RIver includes installing modern sensors to continuously record the nutrient loads at the entrance, the exit and in other pertinent locations of Pool 16. Multiple monitoring locations allows more accurate modeling of nutrients and the sensors can be strategically placed to record nutrient load patterns due to floods, seasonal patterns due to agricultural trends and/or weather, the function of nutrient processing within the pool, or other major occurrences (Carver, 2008). The fact that no other organization has the current ability to record continuous, real-time nutrient data within the Mississippi River provides reason that the Pool 16 observatory may have a significant part in redefining nutrient transport in the Upper Mississippi River Basin and the understanding of the Gulf hypoxia (Carver, 2008). Six high-tech sensors have been deployed in Pool 16 from 2008-2010 recording real-time data such as nitrate, dissolved oxygen, turbidity, temperature and pH. The sensors have collected real-time data at the following locations (Figure 1.3): * Lock and Dam 15 * mouth of the Rock River * along the river bank at the town of Buffalo, IA * in the backwaters of Andalusia Island * along the river bank at LACMRERS * Lock and Dam 16. The collected data now needs to be analyzed not only to understand the data patterns, but to determine whether the data is reliable and makes sense. The main data series that this study focuses on is nitrate concentrations. Nitrate data is analyzed based on the natural patterns observed, how nitrate concentrations are affected by occurrences, and how nitrate patterns are directly related to other measured data such as dissolved oxygen and temperature. The sensors also need to be researched to determine if they are the best piece of technology for our needs and whether the sensors are able to record reliable data. Therefore, the objectives of this study are as follows: * Deploy several sensors in a short amount of time in Pool 16 to determine the efficiency of longer term deployments. * Investigate diurnal phenomena in highly time resolved nitrate concentration data from Pool 16. * Investigate seasonal patterns in nitrate concentration data collected from sensors. * Compare diurnal phenomena and seasonal patterns in nitrate concentrations for the Raccoon River and the Mississippi River. * Evaluate sensor performance and data reliability.

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