Thesis (Ph. D.)--Earth and Atmospheric Sciences, Georgia Institute of Technology, 2007. / Wang Yuhang, Committee Chair ; Cunnold Derek, Committee Member ; Weber Rodney, Committee Member ; Nenes Athanasios, Committee Member ; Guillas Serge, Committee Member.

Thesis (Ph. D.)--Chemical and Biomolecular Engineering, Georgia Institute of Technology, 2008. / Teja, Amyn S., Committee Chair ; Frederick, James, Committee Member ; Wine, Paul H., Committee Member ; Eckert, Charles A., Committee Member ; Nenes, Athanasios, Committee Member.

Thesis (Ph.D.)--Montana State University--Bozeman, 2007. / Typescript. Chairperson, Graduate Committee: Walter B. Knighton. Includes bibliographical references (leaves 131-145).

Thesis (I.M.E.S.)--Baylor University, 2009. / Includes bibliographical references (p. 107-118).

The ability to quickly and efficiently locate concealed human remains is crucial in forensic investigations and when locating disaster victims. On occasions when human remains are recovered, correctly assigning a postmortem interval (PMI) may become necessary to corroborate statements or make an identification. While Human Remains Detection canines (HRD canines) provide rapid and sensitive searches, the mechanisms behind their sense of smell remain poorly understood. Over the past ten years, volatile organic compounds (VOCs) have been investigated in an effort to address questions concerning PMI, optimization of training aids, and portable 'sniffing' devices. The approaches taken for investigating VOCs emitted from decomposing tissues buried or otherwise have been diverse. They range from burying entire human bodies and sampling the above-ground volatiles using triple-sorbent traps (TSTs) to isolating small amounts of tissue into glass vials whereby the volatiles are sampled by Solid Phase Microextraction (SPME). The resulting studies have led to large quantities of data that are difficult to interpret and compare between studies. Furthermore, the restrictions surrounding access to human remains have caused many studies to use other animals, (pigs, chickens, cows, and deer) in particular the domestic pig, due to its similarities in hair coverage and tissue ratios. There have been several studies that attempt to address the effects that burial has on the resulting VOCs. However, the addition of a complex matrix to a process that already has many variables has caused difficulty in data interpretation. The purpose of this study was to identify how freezing and the presence of soil affect the VOC profiles of various tissue types (blood, bone, fat, small intestine, muscle, and skin) obtained over six weeks of decomposition. In order to accomplish this, the study was performed in three parts. The first part used fresh pig samples obtained only hours after euthanization, the second part utilized tissues from the same areas of the pig after the samples had been frozen for 6 weeks and the third part combined soil with three of the tissue types (blood, bone, muscle). SPME was employed at room temperature using a 65 µm PDMS/DVB coated fiber as the adsorbent material to extract the VOCs from the headspace. The use of SPME as the extraction method allowed for direct desorption and subsequent analysis into the injection port of the GC/MS. User-defined integration parameters were applied to each resulting chromatogram in an effort to identify what impact, if any, freezing and soil had on the resulting VOC profiles. The results obtained in this study suggest that the freezing and thawing of tissue samples have varying effects on the resulting chromatograms based on the complexity of the tissue-type. This implies that prolonged use and storage of some, commonly utilized, training aids may not be providing the most reliable scent profile for the HRD canines. Results obtained from the soil study were complex, but several overall trends were observed in the release and production of different compound classes. Comparisons to previous studies using similar extraction procedures demonstrate the need for a standardized protocol for future decomposition studies.

The mechanisms and timescales associated with the triggering of caldera-forming eruptions remain ambiguous and poorly constrained. Do such eruptions start vigorously, then escalate, or can there be episodicity? Are they triggered through internal processes (e.g. recharge, buoyancy), or can external modulations play an important role? Key to answering these questions is the ability to reconstruct the state of the magma body immediately prior to eruption. My dissertation research seeks to answer these questions through detailed investigation of four voluminous caldera-forming eruptions: (1) 650 km3, 0.767 Ma Bishop Tuff, Long Valley, (2) 530 km3, 25.4 ka Oruanui eruption, Taupo, (3) 2,500 km3, 2.08 Ma Huckleberry Ridge Tuff, Yellowstone and (4) 250 km3, 26.91 Ma Cebolla Creek Tuff, Colorado. The main techniques I applied integrated glass geochemistry (major, trace and volatile), diffusion modeling, and detailed field sampling. In chapters two, three, and four these methods are applied to the initial fall deposits of three supereruptions (Bishop, Oruanui and Huckleberry Ridge) that preserve field-evidence for different opening behaviors. These behaviors range from continuous deposition of fall deposits and ignimbrite (Bishop), to repetitive start/stop behavior, with time breaks between eruptive episodes on the order of weeks to months (Oruanui, Huckleberry Ridge). To reconstruct the timescales of opening activity and relate this to conduit processes, I used two methods that exploit diffusion of volatiles through minerals and melt, providing estimates for the rate at which magmas ascended to the surface. This knowledge is then integrated with the pre-eruptive configuration of the magma body, based on melt inclusion chemistry, to interpret what triggered these systems into unrest. Finally, in chapter five I take a different approach by integrating geochemical data for melt inclusions and phenocryst minerals to test whether the mechanism of heat and volatile recharge often called upon to trigger crystal-rich dacitic magmas (the so-called monotonous intermediates), is applicable to the Cebolla Creek Tuff. This dissertation includes both previously published and unpublished co-authored material, and three online supplementary excel files.

Nowadays, researchers are trying to shrink the memory cell in order to increase the capacity of the memory system and reduce the hardware costs. In recent years, there has been a revolution in electronics by using fundamentals of physics to build a new memory for computer application in order to increase the capacity and decrease the power consumption. Increasing the capacity of the memory causes a growth in the chip area. From 1971 to 2012 semiconductor manufacturing process improved from 6µm to 22 µm. In May 2008, S.Williams stated that "it is time to stop shrinking". In his paper, he declared that the process of shrinking memory element has recently become very slow and it is time to use another alternative in order to create memory elements [9]. In this project, we present a new design of a memory array using the new element named Memristor [3]. Memristor is a two-terminal passive electrical element that relates the charge and magnetic flux to each other. The device remained unknown since 1971 when it was discovered by Chua and introduced as the fourth fundamental passive element like capacitor, inductor and resistor [3]. Memristor has a dynamic resistance and it can retain its previous value even after disconnecting the power supply. Due to this interesting behavior of the Memristor, it can be a good replacement for all of the Non-Volatile Memories (NVMs) in the near future. Combination of this newly introduced element with the nanowire crossbar architecture would be a great structure which is called Crossbar Memristor. Some frameworks have recently been introduced in literature that utilized Memristor crossbar array, but there are many challenges to implement the Memristor crossbar array due to fabrication and device limitations. In this work, we proposed a simple design of Memristor crossbar array architecture which uses input feedback in order to preserve its data after each read operation

Made available in DSpace on 2014-06-11T19:27:56Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-02-25Bitstream added on 2014-06-13T19:56:56Z : No. of bitstreams: 1 mazoti_ma_me_botfm.pdf: 303335 bytes, checksum: 4f4fd9740f381b988fb0ea70236c2a7c (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Introdução. Cirurgia gera no paciente uma resposta inflamatória conhecida como stress. Não está esclarecido o papel dos anestésicos voláteis e venosos na modulação do perfil de citocinas inflamatórias em pacientes saudáveis submetidos a cirurgias eletivas pouco invasivas. Assim, o objetivo deste trabalho foi estudar o perfil das citocinas IL-1 , IL- 6, IL-8, IL-10, IL-12 e TNF- frente à anestesia inalatória com isoflurano e intravenosa com propofol, em pacientes saudáveis submetidos a cirurgias eletivas pouco invasivas. Métodos. Quarenta pacientes ASA I, submetidos à cirurgia de otorrinolaringologia, foram alocados ao acaso para receber anestesia com isoflurano 1 CAM (concentração alveolar mínima) (n = 20) ou com propofol 2 a 4 μg mL-1 (n = 20). Também foram administrados fentanil 5 mg kg-1 e brometo de rocurônio 0,6 mg kg-1 a todos os pacientes. Foram coletados 10 mL de sangue venoso de cada paciente em cada um dos seguintes momentos: antes do início da cirurgia e anestesia (M1), 2 h após o início da cirurgia (M2) e no dia posterior ao ato anestésico-cirúrgico (M3). As concentrações plasmáticas das interleucinas IL-1β, IL-6, IL-8, IL-10 e IL-12 e do fator de necrose tumoral TNF-α foram mensuradas em cada amostra pela técnica de citometria de fluxo, utilizando o método Cytometric Bead Array (CBA). Amostras de sangue venoso de quinze voluntários não submetidos a stress também foram coletadas como controle, dosando nessas amostras as mesmas citocinas. Resultados. A comparação das concentrações plasmáticas de citocinas entre os grupos de anestésicos (M1) e o grupo de voluntários mostrou aumento de IL-8 nos grupos propofol e isoflurano. Os pacientes dos grupos isoflurano e propofol apresentaram baixas concentrações plasmáticas das citocinas pró-inflamatórias IL-1 , IL-12 e TNF- e da anti-inflamatória... / Introduction. A surgery causes in the patient an inflammatory response known as stress. The role of volatile and venous anesthetics on the modulation of inflammatory cytokine profile in healthy patients subjected to minimally invasive elective surgeries is not elucidated. Thus, the aim of this paper was to study the profile of cytokines IL-1 , IL-6, IL-8, IL-10, IL-12 and TNF- under inhalation anesthesia with isoflurane and intravenous anesthesia with propofol in healthy patients subjected to minimally invasive elective surgeries. Methods. Forty ASA-I patients, subjected to otorhinolaryngology surgery, were randomly allocated to receive anesthesia with isoflurane 1 MAC (minimum alveolar concentration) (n = 20) or propofol 2 to 4 μg mL-1 (n = 20). Fentanyl 5 mg kg-1 and rocuronium bromide 0.6 mg kg-1 were also administered to all patients. Venous blood (10 mL) was collected from each patient at each of the following times: before the beginning of surgery and anesthesia (T1), 2 h after the beginning of surgery (T2), and on the day after the anesthetic-surgical procedure (T3). Plasma concentrations of interleukins IL-1β, IL-6, IL-8, IL-10 and IL-12 and tumor necrosis factor (TNF-α) were measured in each sample through flow cytometry technique by using the method Cytometric Bead Array (CBA). Venous blood samples from fifteen volunteers not subjected to stress were also collected as control, and the same cytokines were measured. Results. Plasma concentrations of IL-8 increased in Propofol and Isoflurane groups (T1), compared to the group of volunteers. Patients of Isoflurane and Propofol groups had low plasma concentrations of proinflammatory cytokines IL-1 , IL-12 and TNF- and anti-inflammatory cytokine IL-10 throughout the study period. On the other hand, plasma concentration of IL-6 significantly increased at T2 and T3 in the group of patients... (Complete abstract click electronic access below)

Orientador: Neura Bragagnolo / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-15T03:05:45Z (GMT). No. of bitstreams: 1 Iamanaka_BeatrizThie_D.pdf: 2489716 bytes, checksum: f28d257a6355ac8f3f2829d99d83a8be (MD5) Previous issue date: 2010 / Resumo: O café passa por vários processos até chegar a ser consumido como bebida e vários fatores contribuem para a sua qualidade final, dentre eles a população microbiana presente. A contaminação dos grãos pelos microrgranismos é diversificada, envolvendo a participação de bactérias, bolores e leveduras, com a predominância de um ou outro grupo, dependendo da etapa de processamento dos grãos. Existem evidências, ainda não conclusivas de que vários fungos presentes no café podem produzir uma série de compostos que podem vir a prejudicar a qualidade da bebida. Esta pesquisa teve como objetivos analisar a micobiota dos grãos obtidos em diferentes etapas da cadeia produtiva do café; investigar a produção dos compostos voláteis produzidos pelos isolados e o impacto dos mesmos na qualidade da bebida e; avaliar sensorialmente a bebida, correlacionando com os fungos presentes. A micobiota de 41 amostras de grãos de café cru, de duas regiões produtoras do Brasil, Cerrado Mineiro/MG e Piraju/SP foram analisadas. As amostras foram coletados do pé (cereja), do solo (varreção), do terreiro (maduro, seco e passas no pé e verde) e da tulha (estocagem) e comparados dois tipos de preparo dos grãos: secagem natural e cereja descascado. As amostras de Minas Gerais apresentaram baixa infecção fúngica, as principais espécies isoladas foram Eurotium spp. e Fusarium spp. Em relação aos cafés da região de Piraju, houve uma grande diversidade de espécies isoladas, dentre àquelas mais predominantes foram Penicillium brevicompactum, Aspergillus foetidus, Penicillium crustosum e Fusarium spp. Cafés varreção e bóia (seco e passas no pé) caracterizaram-se pela alta incidência de Aspergillus foetidus, apresentando infecção superior a 16% por esta espécie e avaliação sensorial negativa. A foetidus produziu compostos voláteis, como 2-butenal, dimetilbisulfeto no meio de cultura e 1-octen 3-ol quando inoculado no café cru. Estes metabólitos são caracterizados pelo aroma desagradável de terra, mofo, estragado e pungente e foram relacionados como alguns dos compostos responsáveis pelas características negativas na análise sensorial da bebida. Foi constatado também que a presença de algumas espécies fúngicas nos grãos, mesmo em alta percentagem de infecção, não implicou necessariamente na redução da qualidade sensorial da bebida. Amostras com alta freqüência de Penicillium brevicompactum apresentaram avaliação final positiva. Esta espécie destacou-se pela produção de vários compostos voláteis com características positivas como aldeídos (2-octenal, decanal e undecanal) com aroma cítrico e herbal, e cetonas (2-nonanona, 3-nonen-2 ona, 2-undecanona e 2 pentadecanona) de aroma frutal e floral. Portanto, metabólitos produzidos durante o desenvolvimento de espécies fúngicas podem estar relacionados à introdução de características sensoriais de sabor ao café, tanto desejáveis quanto indesejáveis / Abstract: Coffee goes through several processes until consumed as a beverage and many factors contribute to its final quality, including the presence of the microbial population. The coffee beans contamination by microorganisms is diversity envolving bacteria, moulds and yeast, with predominance of one or another and is dependent of the coffee beans processing stages. There is inconclusive evidence that many fungi present in coffee can produce several volatile metabolites that can damage beverage quality. This research had the objectives to analyze the mycobiota ot the coffee beans obtained on the different stages of coffee production chain; investigate the production of volatile compounds produced by the isolates and the impact of them on the beverage quality and carry out sensory evaluation of beverage in relation to the fungal species. The mycobiota of forty-one samples of raw coffee beans from two Brazilian production areas, Cerrado Mineiro/MG and Piraju/SP were analyzed. Samples were collected from the tree (cherry beans), from the soil (¿varreção¿), from the drying yard (ripe, dry, over-ripe and immature) and drying storage (¿tulha¿) and two kinds of bean separation were compared: natural and pulped. The Minas Gerais samples had low fungal infection with the main species being Eurotium spp and Fusarium spp. In relation to the Piraju samples there was a considerable diversity of isolated species and the following were among the most predominant: Penicillium brevicompactum, Aspergillus foetidus, Penicillium crustosum and Fusarium spp. Coffee beans collected from the soil along with the over-ripe ones were a highly incidence of Aspegillus foetidus with a percent infection above 16% and a negative sensorial evaluation. Aspergillus foetidus produced volatile compounds such as 2-butenal, dimethyl dissulfite in the culture medium and 1-octen-3-ol when inoculated on the raw coffee. These metabolites were characterized by as unpleasant aroma of soil, musty, rotten and pungency and they were related as one of the responsible compounds for the negative characteristcs of the sensorial analyses.In this work the presence of some fungal species were found in the beans wich even at high levels of infection, did not necessarily result in a decrease of the sensorial evaluation. Samples with a high percentage of Penicillium brevicompactum infection had a positive final evaluation. This specie stood out from the rest due to the production of many volatile compounds with positive characteristics such as aldehydes (2-octenal, decanal and undecanal) showing citric and herbal aromas and cetones (2-nonanone, 3-nonen-2-one, 2-undecanonc and 2-pentadecanone) showing frutal and floral aroma. Therefore, metabolites produced during fungal growth can be related to the insertion of sensorial properties of flavour on coffee, both positive or negative / Doutorado / Doutor em Ciência de Alimentos

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