Submitted by Évelyn Lira (costa_eve@yahoo.com.br) on 2018-11-03T15:34:17Z No. of bitstreams: 3 TESE_Évelyn Costa Lira.pdf: 5199119 bytes, checksum: 3542649866fd36a1d250872b70b7f22e (MD5) Carta de Encaminhamento.pdf: 120410 bytes, checksum: d948e19f5bae8bee2cb485c166efda6d (MD5) Diploma de Doutorado ou Ata de Defesa.pdf: 129558 bytes, checksum: 3cdafbe7ae427bf6a30e4dd767a402e5 (MD5) / Approved for entry into archive by PPGBIOTEC Biotecnologia (ppg_biotec.ufam@yahoo.com.br) on 2018-11-06T20:43:46Z (GMT) No. of bitstreams: 3 TESE_Évelyn Costa Lira.pdf: 5199119 bytes, checksum: 3542649866fd36a1d250872b70b7f22e (MD5) Carta de Encaminhamento.pdf: 120410 bytes, checksum: d948e19f5bae8bee2cb485c166efda6d (MD5) Diploma de Doutorado ou Ata de Defesa.pdf: 129558 bytes, checksum: 3cdafbe7ae427bf6a30e4dd767a402e5 (MD5) / Rejected by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br), reason: A carta anexada deve ser a "Carta de Encaminhamento para o Autodepósito" disponível em http://biblioteca.ufam.edu.br/servicos/teses-e-dissertacoes Dúvidas? ddbc@ufam.edu.br on 2018-11-07T12:20:35Z (GMT) / Submitted by Évelyn Lira (costa_eve@yahoo.com.br) on 2018-11-07T13:48:25Z No. of bitstreams: 3 TESE_Évelyn Costa Lira.pdf: 5199119 bytes, checksum: 3542649866fd36a1d250872b70b7f22e (MD5) Diploma de Doutorado ou Ata de Defesa.pdf: 129558 bytes, checksum: 3cdafbe7ae427bf6a30e4dd767a402e5 (MD5) Carta de Encaminhamento para Autodepósito.pdf: 146139 bytes, checksum: 0b1a55433f2ef8e007ce7d6045af2443 (MD5) / Approved for entry into archive by PPGBIOTEC Biotecnologia (ppg_biotec.ufam@yahoo.com.br) on 2018-11-07T14:13:03Z (GMT) No. of bitstreams: 3 TESE_Évelyn Costa Lira.pdf: 5199119 bytes, checksum: 3542649866fd36a1d250872b70b7f22e (MD5) Diploma de Doutorado ou Ata de Defesa.pdf: 129558 bytes, checksum: 3cdafbe7ae427bf6a30e4dd767a402e5 (MD5) Carta de Encaminhamento para Autodepósito.pdf: 146139 bytes, checksum: 0b1a55433f2ef8e007ce7d6045af2443 (MD5) / Rejected by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br), reason: O Documento anexado como "Carta de Autodepósito" não é o documento exigido. 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No. of bitstreams: 3 TESE_Évelyn Costa Lira.pdf: 5199119 bytes, checksum: 3542649866fd36a1d250872b70b7f22e (MD5) Diploma de Doutorado ou Ata de Defesa.pdf: 129558 bytes, checksum: 3cdafbe7ae427bf6a30e4dd767a402e5 (MD5) Carta de Encaminhamento para Autodepósito.pdf: 33896 bytes, checksum: cbb2fa1f7645982868cec33dd021fd5d (MD5) Previous issue date: 2017-11-30 / FAPEAM - Fundação de Amparo à Pesquisa do Estado do Amazonas / The role of the human microbiota in health and disease processes has received increased attention due to the ease of characterization of microbial communities using independent culture methods, which are based on the analysis of hypervariable regions of the gene 16S rRNA. The vaginal microbiota is inhabited by microbial communities that play a very important role in the maintenance of vaginal homeostasis and in the presence of colonization by pathogenic microorganisms, but the mechanisms by which they exert this influence are not yet so well defined. in this context, an understanding of their relative abundance and variations is necessary for the recognition of potential pathogenic microorganisms and the physiological processes of protection of this microbiota. This study evaluated the vaginal microbial diversity in four different conditions: I Microbiota Normal II Vaginal Candidosis Microbiota III Bacterial vaginosis microbiota IV microbiota presenting pre-malignant and malignant lesions of the cervix. Cervical samples from 187 women were collected, characterized and diagnosed at the molecular level for the presence of HPV, C. trachomatis, T. vaginalis e N. gonorrhoeae. HPV positive samples were genotyped at ABI 3500 and HPV co-infection were related to the presence of other pathogens and socio-economic and clinical factors obtained through the questionnaire filled out by the volunteers. Significance and association analyzes were performed using the Chi-square Test of Pearson, exact of Fischer’s Test and Kruskal-Wallis test using R 2.9.0. After the groups were composed, four libraries of amplicons of the regions V1-V2 of the gene 16S rRNA and, later sequenced on Ion PGM platform. The sequences generated were analyzed using the QIIME and classified by comparison in the Greengenes database. the prevalence found for HPV was 51.33%, and the most prevalent types were HPV 16, 58 and 33. The prevalence found for CT and TV were 6.42% and 12.83%, respectively, with co- HPV / CT infection in 5.20% and HPV / VT in 6.25% of the women. The DNA of N. gonorrhoeae were not found in samples. as to the estimation of microbial diversity, the number of samples sequenced was enough to guarantee coverage of the total diversity found. Overall abundancy revealed a predominance of the genus lactobacillus on the four study groups, followed by the genres Ureaplasma, Prevotella and Shuttleworthia, followed by the study groups. the greatest microbial diversity was found in the vaginosis group, with the most abundant genera Prevotella, Shuttleworthia and Megasphaera, followed by the lesion group, abundance of genders Ureaplasma, Prevotella e Shuttleworthia. The differences at the species level are extremely necessary for the understanding of the physiological role of the vaginal microbial in the maintenance of autochthonous balance and of pathogenic mechanisms in the development of diseases related to vaginal microbiota. In addition, an understanding of the functionality of the types of CST is necessary to complement what we already know about its structure. Studies are needed to investigate the changes and stability of this microbiota. / O papel da microbiota humana nos processos de saúde e doença tem recebido maior atenção devido à facilidade para a caracterização das comunidades microbianas utilizando os métodos independentes de cultivo, que se baseiam na análise das regiões hipervariáveis do gene 16S rRNA. A microbiota vaginal é habitada por comunidades microbianas que exercem papel importantíssimo para a manutenção da homeostase vaginal e prevenção da colonização por microrganismos patogênicos, mas os mecanismos pelos quais exercem essa influência ainda não são tão bem definidos. Neste contexto, uma compreensão quanto a sua abundância relativa e variações é necessária para o reconhecimento de microrganismos patogênicos potenciais e de processos fisiológicos de proteção dessa microbiota. Este estudo avaliou a diversidade microbiana vaginal em quatro condições distintas: I. microbiota autóctone; II. Microbiota apresentando candidose vaginal; III. microbiota apresentando vaginose bacteriana e; IV. microbiota apresentando lesões pré-malignas e malignas do colo do útero. Amostras cervicais de 187 mulheres foram coletadas, caracterizadas e diagnosticadas a nível molecular quanto à presença de HPV, C. trachomatis, T. vaginalis e N. gonorrhoeae. Amostras HPV+ foram genotipadas em ABI 3500 e a co-infecção do HPV foi relacionada à presença dos outros patógenos e fatores sócio-econômicos e clínicos obtidos através do questionário preenchido pelas voluntárias. Análises de significância e associação foram realizadas através dos Testes Qui-Quadrado de Pearson, Exato de Fischer e Kruskal-Wallis utilizando o R 2.9.0. Após a composição dos grupos, foram montadas quatro bibliotecas de amplicons das regiões V1-V2 do gene 16S rRNA e, posteriormente sequenciadas em plataforma Ion PGM. As sequências geradas foram analisadas utilizando o QIIME e classificadas por comparação no banco Greengenes. A prevalência encontrada para HPV foi de 51,33% sendo que os tipos mais prevalentes foram HPV 16, 58 e 33. As prevalências encontradas para CT e TV foram de 6,42% e 12,83%, respectivamente, sendo observadas co-infecção HPV/CT em 5,20% e HPV/TV em 6,25% das mulheres. O DNA de N. gonorrhoeae não foi encontrado nas amostras. Quanto à estimativa da diversidade microbiana, o número de amostras sequenciado foi suficiente para garantir a cobertura da diversidade total encontrada. A abundância geral revelou predominância do gênero Lactobacillus nos quatro grupos de estudo, seguido pelos gêneros Ureaplasma, Prevotella e Shuttleworthia entre os grupos estudados. A maior diversidade microbiana foi encontrada no grupo Vaginose, tendo como gêneros mais abundantes Prevotella, Shuttleworthia e Megasphaera, seguido pelo grupo Lesão, com abundância dos gêneros Ureaplasma, Prevotella e Shuttleworthia. As diferenças a nível de espécie são extremamente necessárias para o entendimento do papel fisiológico da microbiota vaginal na manutenção do equilíbrio autóctone e de mecanismos patogênicos no desenvolvimento de doenças relacionadas à microbiota vaginal. Além disso, uma compreensão da funcionalidade dos tipos de CST é necessária para complementar o que já sabemos sobre sua estrutura. Estudos são necessários para investigar as mudanças e a estabilidade desta microbiota.

In an earlier project completed in our laboratory a seasonal fluctuation in Phosphoglucomutase (PGM) phenotype frequencies was found, so that the winter bees were almost all heterozygotes and long lived than the summer bees among which homozygotes were significantly at high frequencies at Pgm locus. Same results were obtained in populations of three subspecies, A. m. meda, A. m. caucasica, and A. m. carnica from different climatic regions. In the current study environmental cues related with seasonal change in PGM phenotype frequency was examined along with the correlation between PGM heterozygosity and overwintering success. Cessation of food influx was found to be effective by itself as an environmental cue that causes a sudden and sharp increase in PGM heterozygosity. In addition to that, PGM heterozygosity of the colonies with greater overwintering success was found to be significantly higher than the ones with intermediate or low overwintering success. Benefiting from the previous studies and the results of current study, ethyl oleate was suggested as a chemical signal that functions in the regulation of PGM heterozygosity.

Phosphoglucomutase (PGM) is one of the central enzymes in energy metabolism at a branch point at the head of the metabolic pathway leading into glycogen metabolism, pentose shunt and the main glycolytic cycle, catalyzing the reversible interconversion of glucose-1-phosphate to glucose-6-phosphate. Whole year, month to month analysis of pattern of allozyme variation at Pgm and Hk loci in Apis mellifera L. from three provinces / Kirklareli, Artvin, and Hatay revealed that there is significant seasonal variation of allozyme frequencies at Pgm locus (P&lt / 0.001). The difference in genotype frequencies between summer and winter samples is apparent in Pgm, whereas at Hk locus, which is analyzed as a control there is seasonal variation in genotype frequencies. Biochemical measurements of the enzyme activities and glycogen content of different Pgm genotypes were performed to determine the effect of different Pgm genotypes on the physiological performance of the honeybees and it was observed that both enzyme activity and glycogen amount is higher in heterozygote individuals which are in high frequency during winter months (P&lt / 0.0001). Furthermore, PGM enzyme activity and glycogen content was found to be significantly correlated. These findings clearly demonstrate that biochemical differences between different Pgm genotypes have functional correlates that lead to significant variations in glycogen content of the honeybees and may have adaptive consequences.

No description available.

Includes abstract. / Includes bibliographical references (leaves 74-79). / Historically the platinum group metals (PGMs) have been, and are still being dissolved by means of rather aggressive methods, e.g. aqua regia. Limited research has been conducted into the dissolution of the PGMs using different oxidizing agents. The dissolution of gold on the other hand has been afforded extensive research, and numerous papers and review articles have been published on the subject. The last number of years has seen the biggest application by volume of the PGMs as part of autocatalysts towards the degradation of harmful motor vehicle exhaust gases. This has subsequently sparked research into the recovery of specifically platinum, palladium, and rhodium from spent autocatalysts. Currently pyrometallurgical recovery of PGMs is being employed predominantly. A hydrometallurgical process on the other hand is, based on current technology, still a rather aggressive process that makes for high maintenance costs and an unpleasant environment. Gold has traditionally been dissolved by making use of cyanide, which is still the major route for gold dissolution. Due to environmental concerns lixiviants such as thiosulphate (S2O3 2-), thiourea (H2NCSNH2), and thiocyanate (SCN-) are gaining acceptance due to them being more environmentally friendly and giving good recoveries. These ‘softer’ alternatives have however not been tested on the PGMs. It is therefore the aim of this study to obtain an improved understanding of the leaching of the PGMs using lixiviants less aggressive than aqua-regia. These lixiviants include (i) SCN-, (ii) S2O3 2-, (iii) H2NCSNH2, and (iv) AlCl3/HCl. A thermodynamic study highlighted the fact that thermodynamic data for platinum-, palladium- and rhodium complexes are basically non-existent. To therefore obtain a clearer thermodynamic understanding of the leaching of the platinum group metals by means of these alternative lixiviants, future detailed speciation and thermodynamic investigations need to be conducted. An exploratory electrochemical investigation focusing on open circuit potentials and potentiodynamic scans, showed AlCl3 / HCl / NaOCl to be a good candidate for the leaching of the platinum group metals followed by SCN- / Fe3+ and CS(NH2)2 / Fe3+. Actual leach results, employing virgin autocatalysts as sample material, again highlighted the potential of AlCl3 / HCl / NaOCl as being a good lixiviant system. The surprise package, however, has been SCN- / Fe3+ that rendered very good results for Pd and Pt.

The Diesel Oxidation Catalyst (DOC) is subjected to harsh conditions, causing its performance to diminish over time as the result of different aging mechanisms, which either decreases or lowers the accessibility to the catalyst’s active sites. Previous work using chemisorption to quantify aging progression has resulted in a reproducibility of 17%. In this study it has been attempted to lower this, while also performing performance evaluations to see if correlations exist between dispersion and Light-Off Temperature (LOT). Two catalysts have been investigated, LLC (Low Loading Catalyst) and HLC (High Loading Catalyst). These were hydrothermally aged at 600 C, 700 C and 800 C. In addition to these, two HLC engine cell samples were also investigated. To ensure sample homogeneity, different sample preparation methods were investigated. Catalyst samples were crushed, or had their washcoat layer removed, or were milled and then sieved. A total of 5 runs were done using fresh catalysts of LLC and HLC to calculate the standard deviation. Evaluation of performance was done on all samples using Synthetic Catalyst Activity Testing (SCAT). It was deemed that the only viable sample preparation method was to mill and sieve as other methods would be hard to reproduce. The results showed that the reproducibility for LLC was %STD = 4% and for HLC %STD = 2%. For LLC, a correlation between catalytic activity and dispersion was found. The activity dropped with respect to the dispersion in a close to linear fashion without a large effect on BET surface area. For HLC the dispersion decreased largely upon hydrothermal aging, however no correlation was found with the activity; only when aged at 800 C a significant change in LOT was noted. The BET surface area measurements were inconsistent. Lower dispersion sometimes resulted in higher surface area. Engine cell samples exhibited notable decrease in dispersion, but not in surface area, and did not correlate to the hydrothermally aged catalysts, which might be due to other effects inhibiting CO chemisorption during measurements. / Dieseloxidationskatalysatorn (DOC) utsätts för tuffa förhållanden, vilket medför att dess prestanda minskar med tiden på grund av olika åldringsmekanismer, vilka antingen minskar dess aktiva säten eller minskar tillgängligheten till dessa. Tidigare studier då kemisorption använts för att kvantifiera vilken utsträckning katalysatorn har blivit deaktiverad har resulterat i en reproducerbarhet på 17%. Denna studie har syftat till att minska detta, men även till att utföra prestandamätningar för att se om det existerar korrelationer mellan dispersion och tändtemperatur (LOT). Två katalysatorer undersöktes, LLC (lågladdad katalysator) och HLC (högladdad katalysator), både som färska, men även som hydrotermiskt åldrade i 600 C, 700 C and 800 C. Dessutom undersöktes två motorcellsprover av HLC. För att säkerställa provhomogenitet undersöktes olika provprepareringsmetoder. Katalysatorprover krossades, eller fick washcoat avlägsnat eller maldes samt siktades. Totalt fem körningar gjordes på färska katalysatorer (LLC och HLC). Prestandamätningar gjordes på samtliga prov i Synthetic Catalyst Activity Testing (SCAT). Det bedömdes att den enda gångbara provprepareringsmetoden var att mala samt sikta katalysatorn då de andra metoderna skulle bli svåra att upprepa på ett reproducerbart sätt. Resultaten visade att reproducerbarheten för LLC var %STD = 4% och för HLC %STD = 2%. LLC visade på korrelation mellan katalytisk aktivitet och dispersion. Aktiviteten minskade linjärt utan större förluster i BETytarea. För HLC minskade dispersionen i hög grad med ökad åldringstemperatur, däremot kunde ingen korrelation med katalytisk aktivitet påvisas; enbart då katalysatorn åldrades vid 800 C ändrades LOT signifikant. Förändringarna i BET-ytarean var inte beroende av åldringstemperatur då lägre dispersion ibland resulterade i högre ytarea. För motorcellsproverna uppmättes en märkbart låg dispersion, medan ytarean var relativt oförändrad. Dessa resultat kunde inte korreleras till de hydrotermiskt åldrade proverna, vilket kan bero på att andra effekter inhiberat CO kemisorptionen.

Since the studies of plant gravitropism by Charles Darwin, the identity of specific sensors of gravity in plants has been uncertain. To this date, statoliths - starch granules in the root tips - are considered to play a key role in gravity sensing. The role of statoliths as organelles that mediate the gravity sensing ability of plant roots is based on research that uses plants which have severely impaired ability to synthesize starch in general or have their cells that contain statoliths removed or damaged. This represents methodical imperfections that give rise to alternative explanations, like disturbed auxin flow due to heavy damage to the root tip or unknown involvement of starch from other parts of the plant in gravity perception. Thanks to advances in the field of CRISPR/Cas9 technology, we are now able to produce tissue-specific mutants that might help with clarification of whether starch granules in the root tip are involved in sensing gravity and if so, how significant is this involvement. This diploma thesis aimed to answer these questions by adapting the tissue-specific CRISPR/Cas9 system and using it for the creation of mutants that are starchless specifically in the columella cells. Using this approach, we generated one tissue non-specific mutant line and three tissue-specific mutant...

This study explored the relationships between knowledge, skills, ability, self-efficacy, and experiential learning and performance expectations and satisfaction. The purpose of this study was threefold. First, the study attempted to understand the motivators for student motivation to recommend the program. Second, the study looked at the contribution of both intrinsic and extrinsic motivators for retention and positive word-of-mouth. Further, the research evaluated the relationship of the curriculum in influencing the student’s performance and satisfaction. The study sample consisted of 676 undergraduate students attending one of six PGA Professional Golf management programs in the spring of 2011. The survey instrument was developed specifically for this study after an extensive literature review of higher education analysis, performance, satisfaction and word-of-mouth. The instrument was constructed in eight content areas: knowledge, skills and abilities (KSA); self-efficacy; experiential learning; performance; satisfaction, and word-of-mouth. The findings indicated that experiential learning and to a lesser degree ability made the strongest contribution to the student’s performance and satisfaction. Focus of degree was a predictor of performance while not a predictor of satisfaction. Satisfaction and to a lesser degree performance were strong contributors to the student’s word-of-mouth. Finally, self-efficacy was found to have little relationship to satisfaction or performance contrary to findings in previous research.

Ni-laterites have the potential to become unconventional ore deposits for platinum group elements (PGE). This study was conducted to determine enrichment trends of PGE as a result of the Ni-laterization process. 6 samples were selected by mine workers from the protolith, saprolite, and limonite horizons of the Ni-laterite profile from the Acoje ophiolite block, Luzon, Philippines, and sent to Luleå University of Technology (LTU). 2 samples representing the protolith are described as dunite having undergone serpentinization, 1 sample is a massive chromitite from the saprolite layer of the laterite profile, 1 sample is a massive chromitite from the limonite layer of the laterite profile, and 2 samples are limonitic soils. Total PGE contents of the investigated Acoje samples range from 161-1180 ppb with the highest contents of PGE occurring in the limonite hosted chromitite, and the lowest contents in the saprolite hosted chromitite. C1 chondrite-normalized patterns reveal distinct trends of the PGE in the different sample types: dunite samples have a positive trend from Ir-Pd, the chromitite samples have a negative trend from Ru-Pd with a negative Ir anomaly and the limonite samples have a strong positive trend from Ir-Pd. Rare earth elements (REE) chondrite-normalized patterns of the samples show a negative Ce anomaly in the limonite while the dunite and saprolite-hosted chromitite have negative Eu anomalies. Cr# (Cr/[Al+Cr]) and Mg# (Mg/[Fe2++Mg]) were analyzed using automated mineralogy and produced Cr# values ranging from 0.67 – 0.77 and Mg# values from 0.46 – 0.59.  17 platinum group minerals (PGM) were identified from the Acoje samples: 9 from the dunite, 1 from the saprolite-hosted chromitite, 6 from the limonite-hosted chromitite and 1 from the limonite. Laurite ((Ru,Os)S2) was identified in samples A-02 and A-07 and is the only primary mineral identified. Secondary PGM, thought to have formed due to alteration processes during serpentinization, were identified as alloys composed of: Cu-Pd, Cu-Pt, Pt-Ni-Cu, Pt-Fe, Ir-Ni-(Pt,Fe), and Cu-Pt-Au-(Pd-Ag). PGM are small, measuring consistently <10 µm in diameter. Laurite occurs as inclusions in unfractured chromite. PGM alloys in the dunite samples occur along the boundary of sulfide minerals or within serpentine. PGM identified in the limonite-hosted chromitite occur along interstitial fractures within chromitite or in a Fe-Al oxide matrix within pore spaces.

Platinum-Group Metal (PGM) nanostructures as advantageous alternatives to natural peroxidases have drawn great attention because of their superior catalytic activities, which can effectively enhance performance of enzyme-based in vitro diagnostics. The catalytic activity of metal nanoparticle peroxidase mimics can depend on their size, shape, elemental composition, and surface ligand of PGM nanostructures. Therefore, to develop optimal peroxidase mimics for a few bioanalytical and diagnostic applications, such as enzyme-linked immunosorbent assay (ELISA), it is important to investigate how structural aspects of PGM nanoparticles correlate with the ability of the nanoparticles to serve as functional mimics of protein peroxidase enzymes. In summary, this dissertation has studied: 1) iridium (Ir), platinum (Pt) and Ir/Pt bimetallic nanowire structures as peroxidase mimics, and the effect of different wires' length on their peroxidase-like activities and certain application of sandwich ELISA for the detection of carcinoembryonic antigen (CEA, a cancer biomarker); 2) ultra-small Ir nanoparticles, with an average size of 1.1 nm, supported by WO2.72 nanowire with high catalytic activity. Those Ir nanoparticles were applied to sandwich ELISA and competitive ELISA for sensitive detection of CEA and aflatoxin B1 (AFB1, a carcinogenic toxin), respectively; 3) the size effect of peroxidase mimics on their catalytic activities and performance in biosensing application, where Pd-Ir core-shell nanoparticles were used as a type of model peroxidase mimics. These studies may significantly stimulate further investigations of PGM nanostructures as peroxidase mimics and other potential applications in in vitro diagnostics.