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Design And Development Of Fluorescent Probes For Sensing And Bioimaging Of Nad(P)H, Intracellular Viscosity, And So2, Dilka Liyana Arachchige

Dissertations, Master's Theses and Master's Reports

Understanding the dynamic biochemical and biophysical changes within living systems is vital for advancing disease diagnosis and therapeutic development. This work presents the design and development of innovative fluorescent probes, based on cyanine and coumarin scaffolds, for the highly sensitive and selective detection of key metabolic and biophysical markers, NAD(P)H, mitochondrial viscosity, and sulfur dioxide (SO₂) in live cells and fruit fly larvae. A series of cyanine-based probes were engineered to undergo strong fluorescence enhancement upon reduction by NAD(P)H, enabling real-time visualization of metabolic fluctuations in cancer cells and Drosophila larvae. These probes exhibit excellent sensitivity, mitochondrial targeting capability, and …

Multiscale Computational Chemistry Studies Of The Catalytic Mechanisms Of Non-Heme Fe(Ii)/2-Oxoglutarate-Dependent Oxygenases, Simahudeen Bathir Jaber Sathik Rifayee

Dissertations, Master's Theses and Master's Reports

Enzymes catalyze complex biological transformations. Non-heme Fe(II)/2-oxoglutarate (2OG)–dependent enzymes are highly versatile catalysts capable of selective C–H oxidation, enabling transformations such as hydroxylation, halogenation, desaturation, demethylation, ring rearrangements, epoxidation, and electrophilic aromatic substitution. These enzymes are involved in various biological processes, including fatty acid metabolism, hypoxic signaling, collagen maturation, and transcriptional regulation. Computational Modeling provides detailed knowledge of the enzymes including atomistic details of the important catalytic species, conformational and electronic effects, which are crucial to enzyme engineering and drug design efforts. This dissertation implements advanced multi-scale molecular modelling techniques including Molecular dynamics and Quantum Mechanic / Molecular Mechanics calculations …

Physicochemical Properties Of Atmospheric Aerosols And Their Effect On Ice Cloud Formation, Nurun Nahar Lata

Dissertations, Master's Theses and Master's Reports

Atmospheric aerosols play a vital role in the Earth's energy budget-directly by scattering and absorbing solar radiation and indirectly by acting as cloud condensation nuclei and ice-nucleating particles [1, 2]. The cloud formation potential of aerosol is driven by multiple factors, including surface properties, size distribution, composition, mixing state, phase state, and morphology [3]. The interaction of aerosols with clouds alters the aerosol's physicochemical properties. Those properties can also evolve during transport due to atmospheric processing, in turn, affect the aerosol's ice nucleation and cloud formation activities. This thesis presents experimental studies to understand the role of physicochemical properties of …

High Injection Pressure Dme Ignition And Combustion Processes: Experiment And Simulation, Xiucheng Zhu

Dissertations, Master's Theses and Master's Reports

With nearly smokeless combustion, Dimethyl Ether (DME) can be pressurized and used as a liquid fuel for compression-ignition (CI) combustion. However, due to its lower heating value and liquid density compared with diesel fuel, DME has a smaller energy content per unit volume. To obtain an equivalent energy content of diesel, approximately 1.86 times more quantity of DME is required. This can be addressed by a larger nozzle size or higher injection pressure. However, the effect of high injection pressure on DME spray combustion characteristics have not yet been well understood. In order to fill this gap, spray and combustion …

Direct Measurement Of Rupture Force Of Single Triazole Molecule By Atomic Force Microscope And Solid Phase Synthesis Of Monodisperse Polyethylene Glycols, Ashok Khanal

Dissertations, Master's Theses and Master's Reports

This dissertation includes two topics, which are related to each other: (1) Rupture force measurement of single triazole molecule by atomic force microscope (AFM) and (2) Solid phase stepwise synthesis of polyethylene glycols (PEGs).

The reaction of an alkyne and an azide to form a 1,2,3- triazole has found wide applications. However, the stability of triazole under mechanical stress is unclear. We investigated the cycloreversion at the single molecular level using atomic force microscopy. A mica surface functionalized with a molecule containing a 1,2,3-triazole moiety in the middle and an activated ester at the end was prepared. An AFM tip …