Sensitivity of Semantic Signatures in Text Mining

The rapid development of the Internet and the ability to store data relatively inexpensively has contributed to an information explosion that did not exist a few years ago. Just a few keystrokes on search engines on any given subject will provide more web pages than any time before. As the amount of data available to us is so overwhelming, the ability to extract relevant information from it remains a challenge.;Since 80% of the available data stored world wide is text, we need advanced techniques to process this textual data and extract useful in formation. Text mining is one such process to address the information explosion problem that employs techniques such as natural language processing, information retrieval, machine learning algorithms and knowledge management. In text mining, the subjected text undergoes a transformation where essential attributes of the text are derived. The attributes that form interesting patterns are chosen and machine learning algorithms are used to find similar patterns in desired corpora. At the end, the resulting texts are evaluated and interpreted.;In this thesis we develop a new framework for the text mining process. An investigator chooses target content from training files, which is captured in semantic signatures. Semantic signatures characterize the target content derived from training files that we are looking for in testing files (whose content is unknown). The semantic signatures work as attributes to fetch and/or categorize the target content from a test corpus. A proof of concept software package, consisting of tools that aid an investigator in mining text data, is developed using Visual studio, C# and .NET framework.;Choosing keywords plays a major role in designing semantic signatures; careful selection of keywords leads to a more accurate analysis, especially in English, which is sensitive to semantics. It is interesting to note that when words appear in different contexts they carry a different meaning. We have incorporated stemming within the framework and its effectiveness is demonstrated using a large corpus. We have conducted experiments to demonstrate the sensitivity of semantic signatures to subtle content differences between closely related documents. These experiments show that the newly developed framework can identify subtle semantic differences substantially

Master of Science

thesisPower consumption is a major concern in the present chip design industry. Complementary Metal Oxide Semiconductor (CMOS) technology scaling has led to an exponential increase in the leakage power. The excessive power dissipation can result in more heat generation, which in turn increases the temperature. According to Intel's source, power density increased to a value of 1000 W/cm2 and is approaching the value which is equal to the radiation from the sun's surface (10000 W/cm2). This leads to reliability issues in nanometer-scale CMOS as Silicon starts melting at 1687K. To resolve this issue, we introduce a novel architecture to design nanoelectromechanical switches and implementation results with virtually zero leakage current, ~1 V operation voltage, ~1 GHz resonant frequency and nanometer-scale footprint. Microelectromechanical Switches (MEMS) have very low "on" and very high "off" resistances. Their switching voltages are usually high (5-50 V), switching speeds are usually low (1 MHz) and their footprints tend to be very large (many um2). We have designed and fabricated devices with very low actuation voltages and very high speed using tuning fork geometry compatible with conventional CMOS fabrication technologies. This unique switch geometry decreases the actuation voltage by a factor of 1.4 and doubles the switching speed. It consists of a cantilever beam that acts as a ground plane. Upon actuation, both the ground plane and the switch's main beam move towards each other that makes the center of mass stationary during switching and thus, the switching speed doubles

Using NMR Spectroscopy to Investigate the Binding of DNA to the Globular Domain of Histone H1.0

Linker histones (H1) are a family of lysine-rich proteins that bind to or near the point at which DNA enters and exits the nucleosomal core. A number of studies have shown that H1 expression levels are altered in cancer and that variant-specific changes can be observed in different tumor cells. Although several crystal structures are published for core-histone/DNA complex (nucleosome), the location of linker histone and its interactions are poorly understood. This study attempts to answer several questions regarding the interactions of histone H1 with double stranded partner DNA. Preliminary NMR assignments of this protein have been determined. We also investigated the structural changes in histone H1.0 globular domain induced by DNA binding. During the course of this project it was observed that subtle changes in pH could affect NMR spectral quality. We investigated the pH dependence of the protein stability by performing Circular Dichroism (CD) experiments

Collaborative Concealment of Spatio-Temporal Mobile Sequential Patterns

Recent advances in communication and information technology such as the increasing accuracy of GPS technology and the portability of wireless communication devices coat the way for Location Based Services LBS Based on the data collected from the location aware mobile devices data mining techniques are used to meet the quality requirements of expected services The efficient management of moving object databases has gained much interest in recent years due to the development of mobile communication and positioning technologies A typical way of representing moving objects is to use the trajectories Much work has focused on the topics of indexing query processing and data mining of moving object trajectories but little attention has been paid to the preservation of privacy in this setting The major contribution of this paper is to provide privacy to the users of Location Based Services along with capturing interesting user s behavior pattern by broaden the ideas presented in the datamining-literatur

Design and performance characteristics of cement grouted bituminous mixtures - a review

Cement grouted bituminous mix (CGBM) is a composite type of pavement surfacing prepared by injecting cementitious grouting material in porous asphalt mixtures under the effect of gravity. Over the past few decades, CGBM is gaining attention due to its numerous advantages over flexible and rigid pavement. Several researchers conducted various laboratory and field studies on CGB mixes using different grouting materials. A comprehensive review of the aggregate gradation, binder type, composition of grouting materials, their effect on the mechanical properties and performance characteristics of CGB mixes, micro-mechanical analysis of CGBM, effect of reclaimed asphalt pavement (RAP) on CGBM are summarized

Investigation of the Zinc binding region of Prothymosin-alpha : A spectroscopic and thermodynamic approach to study metal binding in Intrinsically disordered proteins

The goal of this study is to provide a deeper insight into how metals bind intrinsically disordered proteins (IDPs) by taking zinc binding to prothymosin-alpha as a case study. The involvement of metals in several diseases caused by (IDPs) has been noted long ago (Cu binding of [alpha]-synuclein in Parkinsons disease, prion aggregation due to Cu in madcow disease. etc.). However, there is still a lack of understanding of how metal binds IDPs. A deeper insight into metal binding by IDPs is essential for a full understanding of a proteome and to pave a way for drug development. Prothymosin-alpha (Prot[alpha]) is an acidic, natively unfolded, and highly conserved protein located mostly in the nucleus of eukaryotic cells. It consists of 110 amino acids out of which 53 residues are aspartic (D) and glutamic (E) acids thus it is highly acidic. The exact biological role of the protein is unknown. However, it has been shown to be involved in cell proliferation, chromatin remodeling, antiapoptotic activity etc. One of the most interesting characteristics of Prot[alpha] is its ability to bind metal cations like Ca²�, Mg²�, Mn²�, Zn²�, Al²�. In the background of all these cations, Prot[alpha] selectively interacts with Zn²� and undergoes a structural change plus the interactions of the protein with its binding partners are enhanced in the presence of Zn²�. These features underline the importance of Zn²� binding in Prot[alpha]. Very little information is available about Zn²� binding to Prot[alpha]. A recent NMR study has shown that the 48-110 segment of Prot[alpha] is the Zn²� binding region of the protein. Although the 48-110 region is shown to be the Zn²� binding region, the central 50-89 segment, where most of the Zn²� binding residues are located in the protein, was used for all the studies here. To aid in the synthesis, purification, and characterization of highly negatively charged sequences like Prot[alpha](50-89)N50W new amino acid derivatives, 4-pyridylmethyl protected glutamic and aspartic acids were developed and their application was tested. Subsequently a circular dichroism (CD) spectroscopic study on Prot[alpha](50-89)N50W revealed that the peptide, like the full length protein, undergoes a structural change in the presence of Zn²� and both the full protein and the peptide were saturated at 75 eq of Zn²� indicating that the majority of Zn added binds in this region. The above study had also shown that selective binding of Zn²� by Prot[alpha](50-89)N50W is due to sequence specificity and not solely because of electrostatic interactions between Prot[alpha](50-89)N50W and Zn²�. Further the CD and differential scanning calorimetry (DSC) studies have shown that Prot[alpha](50-89)N50W undergoes a structural change similar to an alpha helix when heated from 20-80°C. To set the stage for determining the specific glutamic and aspartic residues in Prot[alpha] that act as ligands for Zn²�, a proof of principle for spin inversion recovery experiments has been provided using Zn²� binding to EDTA as a model. This idea can further be extended to Prot[alpha](50-89)N50W to understand if Zn²� binds to a specific set of residues or if several degenerate binding sites exist.Ph.D

Attack resilient GPS based timing for phasor measurement units using multi-receiver direct time estimation

Modern power distribution systems are incorporating Phasor Measurement Units (PMUs) to measure the instantaneous voltage and current phasors at different nodes in the power grid. These PMUs depend on Global Positioning Systems (GPS) for precise time and synchronization. However, GPS civil signals are vulnerable to external attacks because of its low power and unencrypted signal structure. Therefore, there is a need for the development of attack resilient GPS time transfer techniques to ensure power grid stability. To counteract these adverse effects, we propose an innovative Multi-Receiver Direct Time Estimation (MR-DTE) algorithm by utilizing the measurements from multiple GPS receivers driven by a common clock. The raw GPS signals from each receiver are processed using a robust signal processing technique known as Direct Time Estimation (DTE). DTE directly correlates the received GPS signal with the corresponding signal replica for each of the pre-generated set of clock states. The optimal set of clock candidates is then determined by maximum likelihood estimation. We further leverage the known geographical diversity of multiple receivers and apply Kalman Filter to obtain robust GPS timing. We evaluate the improved robustness of our MR-DTE algorithm against external timing attacks based on GPS field experiments. In addition, we design a verification and validation power grid testbed using Real-Time Digital Simulator (RTDS) to demonstrate the impact of jamming, meaconing (i.e., record-andreplay attack) and satellite data-level anomalies on PMUs. Later, we utilize our power grid testbed to validate the attack-resilience of our proposed MR-DTE algorithm in comparison to the existing techniques such as traditional scalar tracking and Position-Information-Aided Vector Tracking

DESIGN AND EVALUATION OF LIQUISOLID COMPACTS OF NEBIVOLOL HYDROCHLORIDE

Objective: The aim of this study was to investigate the potential of a liquisolid system to improve the dissolution rate and the bioavailability of nebivolol hydrochloride. Methods: Solubility of nebivolol was determined in different nonvolatile solvents to finalize the best nonvolatile vehicle having maximum solubility. The liquisolid compacts were prepared using Fujicalin as a carrier material, Aerosil 200 as a coating material, Polyethylene glycol 400 as a liquid vehicle, and Croscarmellose sodium as a super disintegrating agent. 23 full factorial design was used to optimize the formulation in which the drug concentration, PVP K 30, Excipient ratio (R), and nebivolol containing nonvolatile solvent liquid level were selected as independent variables by using design expert software. The eight liquisolid compact formulations were prepared. Nebivolol liquisolid compacts were evaluated for drug content, tablet hardness, Friability, disintegration, and dissolution. An in vivo study was carried out in male Wistar rats. Results: The solubility of nebivolol hydrochloride in polyethylene glycol 400 was found to be greater than the other nonvolatile solvents. The liquisolid system of nebivolol was formulated successfully using Fujicalin, Aerosil 200, and polyethylene glycol 400. In vitro evaluation parameters for the liquisolid compact were within the prescribed limits. It was found that optimized liquisolid tablet formulation showed higher dissolution than the marketed tablet, with 88.33±0.94 % drug release within 120 min and the drug release was more than 75 % in 30 min for nebivolol LS-3N, which is optimized. LS-3N liquisolid compacts follow the Peppas model and exhibited first-order release. Conclusion: The liquisolid compacts can be a promising alternative for the formulation of water-insoluble drug nebivolol hydrochloride with improved dissolution and bioavailability

BIOANALYTICAL RP-HPLC METHOD DEVELOPMENT AND VALIDATION OF CLOPIDOGREL BISULFATE IN WISTAR RAT PLASMA AND ITS APPLICATION TO PHARMACOKINETIC STUDY

Objective: A novel, simple, precise, accurate, sensitive, and reproducible HPLC method for determining clopidogrel bisulfate in Wistar rat plasma was developed and validated. Methods: The chromatographic separation was performed using Xterra C18 (250 x 4.6 mm, 5μ) column. Mobile phase composed of Acetonitrile ACN: 0.05M potassium dihydrogen orthophosphate buffer pH 4.2 and in the ratio of 75:25% v/v at a flow rate of 1.2 ml/min. Detection was carried out using a PDA detector at 220 nm. The bioanalytical clopidogrel method was validated as per ICH guidelines. Results: The selected chromatographic condition was found to efficiently separate clopidogrel bisulfate (RT-2.838 min). The calibration curve was linear over the concentration range 40-200 ng/ml in Wistar rat plasma with a correlation coefficient of 0.999, respectively. The precision study revealed that the cumulative percentage variation was within the acceptable limit, and accuracy research showed the value of mean percent recovery between 99.72-99.83 %. Conclusion: A simple, rapid, specific, accurate, and precise analytical method was developed and validated using Wistar rat plasma. The technique was strictly validated according to the ICH guidelines. Acquired results demonstrate that the proposed strategy can be effortlessly and advantageously applied for routine analysis of clopidogrel in the Wistar rat plasma