PART I. A modified Hadamard transform has been developed and applied to the analysis of biologically active species using capillary electrophoresis. Hadamard transformations, a matrix based multiplexing technique, when coupled with a capillary electrophoresis instrument capable of rapid sample injection, provides a means to semi-continuously inject samples. The multiple injections separate, interpenetrate, and are detected as the summation of the multiple injections. Deconvolution of the multiplexed signal by multiplication with the inverse of the injection matrix yields a single injection electropherogram that exhibits improved S/N. In modified Hadamard transform capillary electrophoresis (mHTCE), an injection sequence of half the length as conventional HTCE (cHTCE) is utilized. Modifying the manner in which the raw data is manipulated before deconvolution facilitates the reduced injection sequence. When coupled with software, mHTCE can reduce the collection time for a Hadamard sequence by up to 48%. The substantial time reduction afforded by mHTCE is utilized to demonstrate the first time-resolved application of Hadamard transformations for the analysis of neurotransmitters. Additionally, mHTCE has been demonstrated as a means to improve the sensitivity for analysis of amino acids and proteins including gamma-aminobutyric acid, dopamine, and enhanced green fluorescent protein (EGFP) with picomolar detection limits.Part II. Two-photon excitation provides a means to activate chemical and physical processes with high spatial resolution and improved depth penetration compared to one-photon excitation. When combined with three-dimensional lithographic microfabrication (3DLM), these advantages provide a means to fabricate complex structures through radical and cationic two-photon induced polymerization (TPIP). A strategy for realizing high-fidelity microstructures is reported that considers the inherent structural limitations of acrylate monomers. Utilizing this strategy, a series of high-fidelity microstructures is reported for application in microfluidic devices, microelectromechanical systems (MEMS), and microoptical devices such as photonic bandgap (PBG) crystals. Improved periodicity is reported here for f.c.c. PBG crystals compared to earlier examples through addition of micromechanical supports that provide increased strength to the high-aspect ratio crystals. To extend TPIP to cationic polymerization, a series of two-photon activatable photoacid generators has been developed. The new PAGs exhibit one to two orders of magnitude lower polymerization threshold intensities than conventional ultraviolet-sensitive initiators.

International Telemetering Conference Proceedings / October 13-16, 1986 / Riviera Hotel, Las Vegas, Nevada / In most transmission channels, bandwidth is at a premium and an important attribute of any good digital signalling scheme is to optimally utilise the bandwidth for transmitting the information. The Data Compression System in this way plays a significant role in the transmission of picture data from any Remote Sensing Satellite by exploiting the statistical properties of the imagery. The data rate required for transmission to ground can be reduced by using suitable compression technique. A data compression algorithm has been developed for processing the images of Indian Remote Sensing Satellite. Sample LANDSAT imagery and also a reference photo are used for evaluating the performance of the system. The reconstructed images are obtained after compression for 1.5 bits per pixel and 2 bits per pixel as against the original of 7 bits per pixel. The technique used is uni-dimensional Hadamard Transform Technique. The Histograms are computed for various pictures which are used as samples. This paper describes the development of such a hardware and software system and also indicates how hardware can be adopted for a two dimensional Hadamard Transform Technique.

No description available.

Neurological and neuroendocrine disorders result from signaling dysregulation at the molecular, cellular, and multi-cellular levels. This dissertation presents the development of separation methods, using capillary zone electrophoresis (CZE) and capillary liquid chromatography (CLC), for detecting and quantifying small molecules, peptides, and proteins involved in cellular signaling. CZE is a rapid separation technique, making it ideal for monitoring cellular dynamics with high temporal resolution. An ultraviolet - light emitting diode was used for photolytic optical gating of caged fluorophore-labeled biogenic amines, common functional groups in neurotransmitters. Additionally, a novel caged fluorophore with faster reaction kinetics than commercially available dyes was used to label reduced thiols and primary amines in the presence of o-phthalaldehyde. Together this light source and novel caged dye illustrate the utility of these methods for monitoring chemical dynamics during continuous sampling. Many cellular second messengers, including inositol phosphates, are known to exist within the cell, but their dynamics and intermolecular interactions are poorly understood since they lack chromophores or electroactive functional groups making direct detection difficult. Utilizing CZE with capacitive coupled contactless conductivity detection (C4D), biological phosphates were separated and detected based on their high anionic charge, suggesting the utility of C4D in label-free detection of biological molecules. The techniques described above require higher sensitivity to monitor physiologically relevant analyte concentrations; therefore, Hadamard transform capillary electrophoresis (HTCE) was used as a multiplexing method in which multiple separations were performed simultaneously. HTCE resulted in increased sensitivity by decreasing the random background noise. Peptides and proteins propagate signals within or between cells; yet, they are difficult to separate and detect by CZE since their highly charged surfaces result in non-specific adsorption to the capillary wall. To minimize these interactions, stable hybrid phospholipid bilayers were prepared as capillary coatings for CZE separations of cationic proteins. Additionally, stabilized phospholipid bilayer coatings were formed on silica particles through redox polymerization of synthetic, polymerizable lipids. These bilayers were stable after exposure to surfactant, organic solvents, and after storage for one month, suggesting their value as lipid chromatography stationary phases for future incorporation of transmembrane proteins to analyze binding interactions with small molecules.

The problem of determining an objective means for assessing local characteristics of television subpictures in a Hadamard transform multicoder scheme is stated and discussed. Detailed investigations of transform domain coefficient statistical characteristics for different test images have been conducted. Both monochrome and colour signals were used, as well as different transform sizes and shapes. " Directing Indexes " are proposed which, depending on the inter-relationships among transform coefficients and groups of coefficients, direct each subpicture to the appropriate coder. Three indexes in the case of monochrome signals are proposed, each with its own computational procedures and application requirements. Necessary modifications and changes for application of some indexes on colour signals are also discussed. The proposed technique of indexing eliminates the necessity of equal distribution of subpictures among 'activity classes', a major disadvantage encountered in present activity index. Coders to be used with each directing index are devised and tested, subject to an arbitrary bit rate of 2 bits per pixel, with satisfactory performance compared with some published results for other techniques.

No description available.

In this thesis, one finalist cipher of the Advanced Encryption Standard (AES) block cipher contest, Twofish proposed by Schneier et al, is studied in order to observe the validity of the statement made by Arikan about the randomness of the cipher, which contradicts National Institute of Standards and Technology (NIST)&rsquo / s results. The strength of the cipher to cryptanalytic attacks is investigated by measuring its randomness according to the avalanche criterion. The avalanche criterion results are compared with those of the Statistical Test Suite of the NIST and discrepancies in the second and third rounds are explained theoretically.

No description available.

The problem of determining an objective means for assessing local characteristics of television subpictures in a Hadamard transform multicoder scheme is stated and discussed. Detailed investigations of transform domain coefficient statistical characteristics for different test images have been conducted. Both monochrome and colour signals were used, as well as different transform sizes and shapes. " Directing Indexes " are proposed which, depending on the inter-relationships among transform coefficients and groups of coefficients, direct each subpicture to the appropriate coder. Three indexes in the case of monochrome signals are proposed, each with its own computational procedures and application requirements. Necessary modifications and changes for application of some indexes on colour signals are also discussed. The proposed technique of indexing eliminates the necessity of equal distribution of subpictures among 'activity classes', a major disadvantage encountered in present activity index. Coders to be used with each directing index are devised and tested, subject to an arbitrary bit rate of 2 bits per pixel, with satisfactory performance compared with some published results for other techniques.

No description available.