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2015

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Enso Modulation Of The Qbo, And Qbo Influence On Tropical Convection, Wei Yuan Dec 2015

Enso Modulation Of The Qbo, And Qbo Influence On Tropical Convection, Wei Yuan

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

We look into the ENSO modulation of QBO amplitudes and periods using IGRA data, for the time from the 1950s to the 2010s (the whole period), and the separated time intervals before 1982 and after 1990. For the whole period and the time interval after 1990, the QBO has longer period and larger amplitude during La Niña than during El Niño. However, before 1982 there is no conclusive relationship between the QBO amplitude for the two ENSO phases, although the QBO period is still longer during La Niña. Since the period of the QBO is determined by the magnitude of …

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Net N2 Fluxes In Muddy Sediments Of Great Peconic Bay: Rates, Pathways & Controls, Stuart Waugh Dec 2015

Net N2 Fluxes In Muddy Sediments Of Great Peconic Bay: Rates, Pathways & Controls, Stuart Waugh

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

Abstract of the Dissertation NET N2 FLUXES IN MUDDY SEDIMENTS OF GREAT PECONIC BAY: RATES, PATHWAYS & CONTROLS by Stuart Waugh Doctor of Philosophy in Marine and Atmospheric Sciences Stony Brook University 2015 Depending on its form, nitrogen (N) can exert a dominant control on marine productivity and ecosystem structure. Multiple geochemical processes are involved in redox transformations of nitrogen (N) in marine sediments. In coastal benthic environments, a number of abiotic and biological environmental factors control the extent to which these processes are relevant and therefore the outcomes of sedimentary N transformations. This dissertation seeks to quantify rates of …

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Radium Isotopes As Tracers Of Pore Water Dynamics In Two Long Island Salt Marsh Systems, Camilo Salazar Dec 2015

Radium Isotopes As Tracers Of Pore Water Dynamics In Two Long Island Salt Marsh Systems, Camilo Salazar

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

A study of pore water residence time as traced by short-lived radium (Ra) isotopes (224Ra and 223Ra) was conducted on two marsh systems in the south shore of Long Island, New York. Pore water was collected in July (summer) and November-December (winter) of 2013 at depths of 20 cm and 120 cm over three-station transects from the inner marsh to the marsh edge adjacent to a tidal channel. One of the marsh systems is the Wertheim Nationals Wildlife Refuge (NWR), from which two marshes were sampled; Wertheim 1 (W1), a restored marsh, and Wertheim 2 (W2), non-restored. The second marsh …

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Marine Acoustics And Habitat Mapping In The Peconic Estuary, Ny, Michael Patrick White Dec 2015

Marine Acoustics And Habitat Mapping In The Peconic Estuary, Ny, Michael Patrick White

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

As coastal populations grow, there is an increasing need for better spatial management of the seafloor. Multibeam backscatter data can be a powerful tool for habitat mapping and segmenting large areas of the seabed, based on similar physical characteristics. In order to increase the effectiveness of backscatter data sets, MBES data from the Peconic Estuary, NY, is reprocessed using newly developed software. These mosaics are less noisy compared to prior results. The relationship between grain size and backscatter is found to have a good correlation in the Peconic Estuary and a simple regression is used to predict mean phi size …

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Chemical Aging And Cloud Condensation Nuclei Activity Of Biomass Burning Aerosol Proxies In The Presence Of Oh Radicals, Jonathan Hall Slade Dec 2015

Chemical Aging And Cloud Condensation Nuclei Activity Of Biomass Burning Aerosol Proxies In The Presence Of Oh Radicals, Jonathan Hall Slade

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

Biomass burning aerosol (BBA) can adversely impact regional and global air quality and represents a significant source of organic aerosol (OA) to the atmosphere that can affect climate. Aerosol particles can alter the transfer of radiation in earth's atmosphere directly by scattering and absorbing radiation or indirectly via cloud formation. Gas-to-particle, also termed heterogeneous, oxidation reactions can significantly alter the particle's physical and chemical properties. In turn, this can lead to the degradation of biomolecular markers for air quality-related aerosol source apportionment studies, the particles' lifetime, and modify the particles' abilities to serve as cloud condensation nuclei (CCN). However, the …

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Theoretical Investigation Of Sub-Lattice Imaging By 4-D In-Line Holography, Guanzhong Huang Dec 2015

Theoretical Investigation Of Sub-Lattice Imaging By 4-D In-Line Holography, Guanzhong Huang

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

In conventional annular dark-field scanning transmission electron microscopy, the beam rasters on a thin sample and the signal map by integrating the transmitted electrons with an annular shaped detector in the diffraction space. Because the scattering cross sections for high-angle scattered electrons is proportional to the atomic number square. The resulting image has a so called Z-contrast. Z-contrast images can give atomic resolution images of atomic columns however it has an inherent problem—light elements buried in the tails of the heavy elements containing columns. In this thesis, we propose to use a pixelated a 2-D imaging detector to record the …

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Self-Supported Pani /Wo3 Hybrid Photocatalyst For Dye Remediation, Xicheng Jia Dec 2015

Self-Supported Pani /Wo3 Hybrid Photocatalyst For Dye Remediation, Xicheng Jia

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

Polyaniline (PANI), one of the most important conducting polymers, has been studied intensely in recent years for its unique properties. Tungsten trioxide (WO3), on the other hand, is an important functional semiconductor. In this work, a hybrid mat based on PANI and WO3 was synthesized via spin coating and tested as a visible light photocatalyst. A PANI/TiO2 composite photocatalyst was made in the same way and its photocatalytic response was compared to that of PANI/WO3 and of pure WO3, respectively, under visible light for the remediation of methylene blue in water. Furthermore, the effect of salinity on the spontaneous photolysis …

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Development Of Carbon Sequestration Options By Studying Carbon Dioxide-Methane Exchange In Hydrates, Kristine Nicole Horvat Dec 2015

Development Of Carbon Sequestration Options By Studying Carbon Dioxide-Methane Exchange In Hydrates, Kristine Nicole Horvat

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

Gas hydrates form naturally at high pressures (>4 MPa) and low temperatures (<4 oC) when a set number of water molecules form a cage in which small gas molecules can be entrapped as guests. It is estimated that about 700,000 trillion cubic feet (tcf) of methane (CH4) exist naturally as hydrates in marine and permafrost environments, which is more than any other natural sources combined as CH4 hydrates contain about 14 wt% CH4. However, a vast amount of gas hydrates exist in marine environments, which makes gas extraction an environmental challenge, both for potential gas losses during extraction and the potential impact of CH4 extraction on seafloor stability. From the climate change point of view, a 100 ppm increase in atmospheric carbon dioxide (CO2) levels over the past century is of urgent concern. A potential solution to both of these issues is to simultaneously exchange CH4 with CO2 in natural hydrate reserves by forming more stable CO2 hydrates. This approach would minimize disturbances to the host sediment matrix of the seafloor while sequestering CO2. Understanding hydrate growth over time is imperative to prepare for large scale CH4 extraction coupled with CO2 sequestration. In this study, we performed macroscale experiments in a 200 mL high-pressure Jerguson cell that mimicked the pressure-temperature conditions of the seafloor. A total of 13 runs were performed under varying conditions. These included the formation of CH4 hydrates, followed by a CO2 gas injection and CO2 hydrate formation followed by a CH4 gas injection. Results demonstrated that once gas hydrates formed, they show “memory effect†in subsequent charges, irrespective of the two gases injected. This was borne out by the induction time data for hydrate formation that reduced from 96 hours for CH4 and 24 hours for CO2 to instant hydrate formation in both cases upon injection of a secondary gas. During the study of CH4-CO2 exchange where CH4 hydrates were first formed and CO2 gas was injected into the system, gas chromatographic (GC) analysis of the cell indicated a pure CH4 gas phase, i.e. | all injected CO2 gas entered the hydrate phase and remained trapped in hydrate cages for several hours, though over time some CO2 did enter the gas phase. Alternatively, during the CH4-CO2 exchange study where CO2 hydrates were first formed, the injected CH4 initially entered the hydrate phase, but quickly gaseous CO2 exchanged with CH4 in hydrates to form more stable CO2 hydrates. These results are consistent with the better thermodynamic stability of CO2 hydrates, and this appears to be a promising method to sequester CO2 in natural CH4 hydrate matrices. The macroscale study described above was complemented by a microscale study to visualize hydrate growth. This first-of-its-kind in-situ study utilized the x-ray computed microtomography (CMT) technique to visualize microscale CO2, CH4, and mixed CH4-CO2 hydrate growth phenomenon in salt solutions in the presence or absence of porous media. The data showed that under the experimental conditions used, pure CH4 formed CH4 hydrates as mostly spheres, while pure CO2 hydrates were more dendritic branches. Additionally, varying ratios of mixed CH4-CO2 hydrates were also formed that had needle-like growth. In porous media, CO2 hydrates grew, consistent with known growth models in which the solution was the sediment wetting phase. When glass beads and Ottawa sand were used as a host, the system exhibited pore-filling hydrate growth, while the presence of liquid CO2 and possible CO2 hydrates in Ottawa sand initially were pore-filling that over time transformed into a grain-displacing morphology. The data appears promising to develop a method that would supplant our energy supply by extracting CH4 from naturally occurring hydrates while CO2 is sequestered in the same formations. | 303 pages

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Radiation Damage Study Of A Dpp Polymer Using Transmission Electron Microscope, Sai Bharadwaj Vishnubhotla Dec 2015

Radiation Damage Study Of A Dpp Polymer Using Transmission Electron Microscope, Sai Bharadwaj Vishnubhotla

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

In general polymeric materials are sensitive to the electron beam in the transmission electron microscopes (TEM). Radiolysis or ionization is the primary mechanism by which these materials are damaged under electron irradiation. Moreover, the image resolution of these materials in a TEM is determined by radiation damage. In the following work we determine the radiation sensitivity and damage mechanism for a single crystal organic material 3,6-bis (5-(4-n-butylphenyl) thiophene-2-yl)-2,5-bis (2-ethylhexyl) pyrrolo[3,4-c]pyrrole-1,4-dione (DPP-PR) majorly used for organic photovoltaic (OPV) applications as a donor material. We provide a complete experimental and analysis procedure for radiation damage study by utilizing electron diffraction patterns. First …

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Effect Of Toxicity Of Rdp In Polymer Scaffolds On Fibroblast Cell, Jae Wha Yang Dec 2015

Effect Of Toxicity Of Rdp In Polymer Scaffolds On Fibroblast Cell, Jae Wha Yang

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

The purpose of this thesis is to design substrates with flame retardant and clay to enhance the property of polymer and to study the effect of toxicity of a flame retardant mixed polymer, which had not been conducted in vivo. Therefore the human dermal fibroblast cells, engineered to have green fluorescent membrane (GFFB), were cultured on PS scaffolds with three different conditions: pure PS, PS-Na+-Clay and RDP-Clay. In first part of the study, the polymer samples (PS, PS-Clay and RDP-clay) that would be used as scaffolds were prepared and sterilized to use for cell culture, while testing that sterilization using …

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Learning Mixed Sparse Factor Networks Structure: A Latent Variable Approach, Ruofeng Wen Dec 2015

Learning Mixed Sparse Factor Networks Structure: A Latent Variable Approach, Ruofeng Wen

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

Learning and visualizing complex causal or dependence structure among various variables is of great interest in applied science. Probabilistic Graphical Models, including Bayesian Networks and Markov Random Field, are well-developed tools for such problems, particularly when variables are either all categorical or continuous. In the first and major part of this text, we proposed a novel graphical structure learning approach, the MIxed Sparse FActor Network (MISFAN), to accommodate categorical and continuous variables seamlessly in one sparse Probit latent factor model. Such a network bridges the gap among latent variable models, traditional multivariate analysis and graphical models, can visualize the underlying …

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The Dna Damage Response: P53 Regulation Of The Chk1-Suppressed Pathway And Sphingolipid Metabolism, Brittany Carroll Dec 2015

The Dna Damage Response: P53 Regulation Of The Chk1-Suppressed Pathway And Sphingolipid Metabolism, Brittany Carroll

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

The DNA damage response (DDR) is a complex and interconnected signaling network that dictates whether a cell repairs itself and survives or is damaged beyond repair and eliminated; therefore the proteins in this network must be tightly regulated in order to ensure genomic integrity. Conversely, mutational or epigenetic inactivation of DDR components leads to genomic instability, a hallmark of cancer. Indeed there is a high frequency of DDR defects in human cancers of which mutations in the DDR effector and tumor suppressor protein p53 are the best characterized and occur in greater than 50% of all human cancers. Interestingly, a …

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Functional Study Of Classical Protein Tyrosine Phosphatases In Mammary Epithelial Cells, Mathangi Ramesh Dec 2015

Functional Study Of Classical Protein Tyrosine Phosphatases In Mammary Epithelial Cells, Mathangi Ramesh

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

Reversible protein tyrosine phosphorylation is critical for the dynamic regulation of protein function and is maintained by the synchronized and complementary activity of Protein Tyrosine Kinases (PTKs) and Protein Tyrosine Phosphatases (PTPs). Although considerable progress has been made in understanding the function of PTKs, the study of PTPs has lagged behind. Some PTPs have been implicated as products of oncogenes or tumor suppressors. Particularly in breast cancers driven by the oncogenic receptor tyrosine kinase ERBB2, there is evidence for PTPs playing diverse regulatory roles, suggesting that systematic analysis of PTP function could yield important insights into this field which could, …

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Mechanism Of Type Iii Secretion System-Triggered Killing Of Yersinia In Macrophages, Xiaoying Wang Dec 2015

Mechanism Of Type Iii Secretion System-Triggered Killing Of Yersinia In Macrophages, Xiaoying Wang

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

The mammalian immune system has the ability to discriminate between pathogens and innocuous microbes by detecting conserved molecular patterns. In addition to conserved microbial patterns, the mammalian immune system may recognize distinct pathogen-induced processes, the mechanism of which is poorly understood. Pathogenic Yersinia species utilize a type III secretion system (T3SS) to translocate various bacterial effectors into target cells, which aim to modify multiple host signaling pathways. Interestingly, previous studies have shown that the T3SS in Yersinia pseudotuberculosis leads to decreased survival of this bacterium in primary murine macrophages, the mechanism of which is unknown. Here, we use colony forming …

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Identification Of Differential Gene Pathways In Microarray Data, Qiao Zhang Dec 2015

Identification Of Differential Gene Pathways In Microarray Data, Qiao Zhang

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

A gene pathway typically refers to a group of genes and small molecules that work together to control one or more cell functions. In systems biology, pathway analysis is of paramount biological importance, and recent studies revealed that malfunction of gene pathways could induce disease manifestations, such as cancer. Usually, a gene pathway consists of two components: the upstream factors, which are signaling molecules transmitting stimulus from cell surface to nucleus, and the downstream factors, which respond to cell signaling through changes of their expression levels. Although several methods have been reported for analysis of gene pathways, almost all of …

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Exploring The Role Of Interferons In Adenovirus Replication And Establishment Of Persistent Infection In Normal Human Cells, Yueting Zheng Dec 2015

Exploring The Role Of Interferons In Adenovirus Replication And Establishment Of Persistent Infection In Normal Human Cells, Yueting Zheng

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

Adenoviruses (Ad) are ubiquitous pathogens that infect a wide range of vertebrates and have been recognized in recent years as significant pathogens in immunocompromised patients. Interferons (IFNs) are cytokines that have pleiotropic effects and play important roles in innate and adaptive immunity. IFNs have broad antiviral properties and function by different mechanisms. IFNs fail to inhibit wild-type Ad replication in established cancer cell lines. In this study, I analyzed the effects of IFNs on Ad replication in normal human cells. The results demonstrated that both IFNα and IFNγ blocked wild-type Ad5 replication in primary human bronchial epithelial cells (NHBEC) and …

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¿Fronteras Móviles? El Desierto En Lucio Victorio. Mansilla, César Aira Y Dino Buzzati, Michele Giua Dec 2015

¿Fronteras Móviles? El Desierto En Lucio Victorio. Mansilla, César Aira Y Dino Buzzati, Michele Giua

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

El propósito de este trabajo es analizar los cambiantes significados que adoptan las ideas de frontera y desierto (y también las relaciones entre ambas ideas), en tres textos: Una excursión a los indios ranqueles, (1870) de Lucio V. Mansilla, Ema, la cautiva, (1981) de César Aira, y finalmente Il deserto dei tartari, (1940) de Dino Buzzati. El análisis se concentrará en estos puntos principales: 1. La frontera como espacio y lugar 2. La frontera como un espacio a defender. 3. La frontera como expresión de poder. 4. La frontera como un espacio a conquistar. La manera de proceder no sigue …

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Juan Josã© Saer Desde Juan Josã© Saer: Un Escritor Sin Orillas | Juan José Saer Desde Juan José Saer: Un Escritor Sin Orillas, Luis Alberto Garcia Dec 2015

Juan Josã© Saer Desde Juan Josã© Saer: Un Escritor Sin Orillas | Juan José Saer Desde Juan José Saer: Un Escritor Sin Orillas, Luis Alberto Garcia

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

This dissertation analyzes the work of the writer Juan José Saer (Serodino, Argentina 1937-Paris, France 2005) by identifying the correlation between his essayistic and narrative work, and thus focusing on the convergence zone between these two fields. Saer's writings demonstrate a constant tension between the massive circulation and consumption of cultural products, including the genre of novel, and certain marginalized literature. Specifically, the thesis analyzes aspects that involve his conception of the theory of novel, the fiction as an anthropological speculation, the cultural industry, the role of mass media in literature, and the binomial concept of the reader and public, …

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The Origin Of Contemporary Drug Contraband: A Global Interpretation From Sinaloa, Froylan Vladimir Enciso Higuera Dec 2015

The Origin Of Contemporary Drug Contraband: A Global Interpretation From Sinaloa, Froylan Vladimir Enciso Higuera

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

This dissertation charts the longer history of contemporary drug contraband by focusing on the Pacific state of Sinaloa, the cradle of the Mexican drug trade. Historians working on drug trades in Latin America have now produced many accounts of the development of global drug commodity chains, and of the origins of drug prohibition regimes as well as smuggling and illicit flows. This dissertation is different in its attempt to trace the emergence of drug trafficking as a historically specific set of relationships emerging between states—above all, the United States and Mexico--and global markets, all mediated by shifting cultures of medical …

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Food Waste And Sustainability: Quantifying Food Waste Disposal And Evaluating The Environmental Impacts Of Technologies And Policies, Krista Lee Thyberg Dec 2015

Food Waste And Sustainability: Quantifying Food Waste Disposal And Evaluating The Environmental Impacts Of Technologies And Policies, Krista Lee Thyberg

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

There has been growing interest in establishing food waste prevention and recovery programs throughout the United States. An interdisciplinary systems approach to sustainable food waste management was taken to explore three integrated food waste issues: 1. the quantity of residential, commercial and institutional food waste disposed in the U.S.; 2. the environmental impact of food waste treatment technologies; and, 3. approaches for sustainable waste system planning and the development of food waste management policies. The dissertation begins with a review of the history, contributing factors, impacts, and current practices regarding food waste in the U.S. and globally. The amount of …

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On Using Risk-Benefit Analysis To Assess And Manage Controversial Research, Daniel Rozell Dec 2015

On Using Risk-Benefit Analysis To Assess And Manage Controversial Research, Daniel Rozell

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

Science research in the twenty-first century increasingly results in powerful and rapidly disseminated technologies that raise concerns over technological risk and public safety. A common recommendation for assessing and managing controversial research is to perform a quantitative risk-benefit analysis (RBA) in order to help determine an appropriate course of action. However, these recommendations lack guidelines on how to perform such an assessment. This dissertation lays out a detailed argument why a quantitative RBA should not be used as a basis for making complex policy decisions. Rather, RBA should be regarded as a tool for exploring the impacts of technology on …

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Phylogenetic Systematics And Biogeography Of Lemurs From Madagascar, James Paul Herrera Dec 2015

Phylogenetic Systematics And Biogeography Of Lemurs From Madagascar, James Paul Herrera

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

The evolutionary mechanisms influencing biodiversity include abiotic and biotic factors, such as climate change, vicariance, ecological adaptation, and competition. I investigated evolutionary mechanisms that may have influenced the diversity of lemurs from Madagascar by testing geographic and ecological hypotheses in a phylogenetic framework. I used total-evidence methods to infer the lemur phylogeny and divergence times of extant and extinct species. I then tested macroevolutionary hypotheses about lemur biogeography based on the phylogeny to shed new light on the causes of lemur diversification. I examined macroevolution and biogeography at four geographic scales: island-wide, regions, localities, and multiple transects within localities. I …

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Developing Tools For Cavin-1 Purification And Binding Studies With Caveolin-1, Safa Farjand Siddiqui Dec 2015

Developing Tools For Cavin-1 Purification And Binding Studies With Caveolin-1, Safa Farjand Siddiqui

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

Caveolae are nanoscale invaginations found in the plasma membrane of mammalian cells, and are implicated in numerous essential cellular communication and transport processes. They are characterized by a coat composed of caveolin and cavin proteins. Recent studies of the caveolar coat complex suggest that cavin-1 associates with caveolin-1 during caveolae biogenesis. However, it is not known how this binding occurs. Studies of the spatial and physical interactions between cavin-1 and caveolin-1 can provide valuable insights into the mechanism of caveolae generation. The goal of this study was to test two different fusion tags to purify a sufficient quantity of cavin-1, …

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The Roles Of Sox2 And Canonical Wnt Signaling Pathway In Fate Specification Of Tailbud Bipotential Stem Cells, Yu-Jung Tseng Dec 2015

The Roles Of Sox2 And Canonical Wnt Signaling Pathway In Fate Specification Of Tailbud Bipotential Stem Cells, Yu-Jung Tseng

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

During vertebrate development, formation of the head -to-tail body axis is shaped by a group of unspecified cells at the caudal region of the embryo. The undifferentiated tail bud stem cells are capable of adopting mesodermal or neural cell fates as the embryo develops, but the mechanism of this patterning process remains largely unknown. Our previous studies confirm that Wnt signaling is required in tail bud stem cells to repress the neural transcription factor sox2 and induce mesodermal fate. However, it is unclear if sox2 repression at the cell-autonomous level is the critical factor required for Wnt mediated mesoderm induction. …

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Comparative Morphology Of Primate Distal Phalanges: Implications For Early Primate Evolution And The Origins Of The Primate Nail, Stephanie A. Maiolino Dec 2015

Comparative Morphology Of Primate Distal Phalanges: Implications For Early Primate Evolution And The Origins Of The Primate Nail, Stephanie A. Maiolino

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

Human manual dexterity is strongly enhanced by the presence of flattened nails associated with well-developed apical pads. However, the presence of nails is not unique to humans; it is one of the few traits that unite all living primates. Further, the form of the keratinous structure (nail, claw, etc.) on the ends of primate digits is often considered to be a diagnostic trait of major primate clades; strepsirrhines (lemurs, lorises, and galagos) possess a grooming claw (a specialized nail or claw used to scratch and clean the fur around the head and neck) on each second pedal digit; tarsiers possess …

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Bmp-2 Gene Delivery Using Electrospun Collagen/Plla Scaffold With Surface Adsorbed Transfection Complexes For Bone Formation, Xia Zhao Dec 2015

Bmp-2 Gene Delivery Using Electrospun Collagen/Plla Scaffold With Surface Adsorbed Transfection Complexes For Bone Formation, Xia Zhao

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

Bone tissue engineering provides an alternative to bone grafting. Our laboratory previously developed two different types of electrospun scaffolds for bone tissue engineering, including a DNA containing PLGA/PELA scaffold for delivering genes and a collagen/PLLA scaffold for delivering cells. For this dissertation research, we firstly fabricated a DNA containing PLGA/PELA electrospun scaffold using the same method as previously developed, with the intent of delivering osteogenic growth factor genes for bone regeneration. However, the scaffold shrunk severely after being submerged into aqueous environment and failed to achieve high transfection efficiency in vitro. Subsequently, we used the collagen/PLLA scaffold (originally developed for …

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Effect Of Support On Iron Promoted Rhodium Nanocatalysts For Ethanol Synthesis From Co Hydrogenation, Pamela Carolina Carrillo Sanchez Dec 2015

Effect Of Support On Iron Promoted Rhodium Nanocatalysts For Ethanol Synthesis From Co Hydrogenation, Pamela Carolina Carrillo Sanchez

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

Depleting fossil fuel sources coupled with the deleterious effects of petroleum-based fuel combustion have led to the development of sustainable ways for energy production. One alternative is the production of biofuels like ethanol. Ethanol’s biggest advantages are its high energy density, biodegradability and carbon neutrality. A potential scalable process is the conversion of synthetic gas (syngas: CO, CO2, H2) produced from gasification of biomass with the use of Rh-based catalysts. The work presented in this thesis aimed to study the effect of the introduction of 1, 5, and 10 wt % CeO2 into a TiO2 support on Fe promoted-Rh catalysts …

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Investigations Into The Preparation Of Donor/Acceptor-Substituted Polyacetylenes By Alkyne Polymerization, Feng-Yang Shih Dec 2015

Investigations Into The Preparation Of Donor/Acceptor-Substituted Polyacetylenes By Alkyne Polymerization, Feng-Yang Shih

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

The polymerization of 2-ethynyl-5-hexylthiophene (2E5HT), 2-hexyl-5-((perfluorophenyl)ethynyl)thiophene (HT≡FPh), 2-hexyl-5-(3,3,3-trifluoroprop-1-yn-1-yl)thiophene (HT≡CF3), 1-ethynyl-2,3,5,6-tetrafluoro-4-methoxybenzene (1ETFMB), 1-ethynyl-2,3,5,6-tetrafluoro-4-(trifluoromethyl)benzene (PFPA), and ethynylbenzene with transition metal catalysts (tantalum (V) chloride, molybdenum (VI) tetrachloride oxide, and 2nd Generation Grubbs Catalyst) was investigated. The targeted polymers and copolymers were designed to have both electron-donating and electron-withdrawing groups conjugated to the polyacetylene backbone to tune the electronic and optical properties for potential application in organic photovoltaic solar cells. The optical properties of the resulting oligomers and polymers were analyzed by UV-Vis absorption spectroscopy. | The polymerization of 2-ethynyl-5-hexylthiophene (2E5HT), 2-hexyl-5-((perfluorophenyl)ethynyl)thiophene (HT≡FPh), 2-hexyl-5-(3,3,3-trifluoroprop-1-yn-1-yl)thiophene (HT≡CF3), 1-ethynyl-2,3,5,6-tetrafluoro-4-methoxybenzene (1ETFMB), 1-ethynyl-2,3,5,6-tetrafluoro-4-(trifluoromethyl)benzene (PFPA), and ethynylbenzene with transition …

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Characterization Of Bacterial Multi-Component Regulatory Systems: Nitric Oxide, Quorum Sensing And, Takahiro B. Ueno Dec 2015

Characterization Of Bacterial Multi-Component Regulatory Systems: Nitric Oxide, Quorum Sensing And, Takahiro B. Ueno

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

Bacterial quorum sensing (QS) is an essential cell-to-cell communication system used by bacteria. Bacteria produce and detect small signaling molecules called autoinducers (AIs) to assess their surrounding bacterial population. Once the AI concentration reaches a threshold, the entire bacterial population undertakes a coordinated change in gene expression patterns. Thus, QS enables bacteria to orchestrate population-wide changes in behavior appropriate for different growth phases or environmental conditions. QS is widely spread among bacteria and regulates a wide array of biological functions that are critical for their survival. Controlled manipulation of QS may provide the means for the design of more selective …

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Design, Synthesis, And Biological Evaluation Of Novel Taxoid-Based Small-Molecule Theranostic Pet/Spect Imaging Agents And Nano-Scale Asymmetric Bow-Tie Dendrimer Drug Conjugates Towards Tumor-Targeted Chemotherapy, Tao Wang Dec 2015

Design, Synthesis, And Biological Evaluation Of Novel Taxoid-Based Small-Molecule Theranostic Pet/Spect Imaging Agents And Nano-Scale Asymmetric Bow-Tie Dendrimer Drug Conjugates Towards Tumor-Targeted Chemotherapy, Tao Wang

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

Cancer remains the second leading cause of death in the United States. Traditional chemotherapy relies on highly potent cytotoxic agents, such as paclitaxel and docetaxel, to kill rapidly dividing cancer cells. But these drugs usually cause undesired side-effects due to lack of tumor-selectivity, and decreased efficacy against MDR cancer cell lines. Accordingly, newer generation taxoids were designed and evaluated showing several orders of magnitude greater potency than paclitaxel and docetaxel. Over the past decade, significant advancement has been made on the development of newer generation taxoids based on SAR study. As a selected example of second generation taxoid, SB-T-1214 was …

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