ANTIOXIDANT PROPERTIES OF SINAPIC ACID: IN VITRO AND IN VIVO APPROACH

Objective: This study was aimed to evaluate the antioxidant potential of sinapic acid in both in vitro and in vivo. Recently, we have reported that oral administration of sinapic acid (3,5-dimethoxy 4-hydroxycinnamic acid) an active phyto ingredient widely distributed in rye, mustard, berries, and vegetables has been shown to ameliorate hyperglycemia.Methods: Experimental Type 2 diabetes was induced in male Wistar rats by feeding high-fat diet to induce insulin resistance followed by intraperitoneal administration of a single low dose streptozotocin (35 mg/kg body weight [bw]). Sinapic acid was administered orally at a concentration of 25 mg/kg bw/rat/day for 30 days, and its efficacy was compared with metformin. In vitro, antioxidant scavenging properties of sinapic acid were determined using 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), superoxide, and nitric oxide (NO) assay.Results: Sinapic acid treatment showed a significant decline in the levels of lipid peroxides, hydroperoxides and protein carbonyls in the plasma and vital tissues of diabetic rats. The treatment also improved the antioxidant status in diabetic rats indicating the antioxidant potential of sinapic acid. In addition, the results of DPPH, ABTS, superoxide, and NO radical scavenging assays substantiate the free radical scavenging efficacy of sinapic acid.Conclusion: The results of this study evidenced that sinapic acid possess significant antioxidant properties which in turn may be responsible for its antidiabetic properties

PALATAL RUGOSCOPY AS A METHOD OF SEX DETERMINATION IN FORENSIC SCIENCE

 Objective: The role of forensic science in establishing the personal identity is based on DNA analysis, finger print and dental analysis. When theforensic remains are decomposed making all these sources, unavailable palatal rugae served as an important aid as it is resistant to heat and placeddeep inside the oral cavity in a secure environment. Thus, palatal rugae can be used as an adjunct in the gender determination. This study wasperformed to determine the length, number and the patterns of palatal rugae in males and females on right and left side and thereby determine thegender difference.Methods: A total of 50 subjects were included in the study comprising of 25 males and 25 females. An impression of the maxillary arch was madeusing the hydrocolloid impression material (alginate). The palatal rugae were highlighted using a graphite pencil and the length, number and patternof the rugae were determined using Thomas and Kotze classification. Statistical analysis was performed to determine the two-tailed significance testto determine the significance between the two genders.Results: The wavy pattern was found to highest, followed by curved, straight, circular and unification pattern. The females showed a statisticallysignificant rise in the unification pattern, whereas males demonstrated higher amount of wavy and straight pattern based on descriptive statistics.There was no statistical difference in the length and number of the rugae in males and females.Conclusion: No two palatal rugae are alike and this forms the basis of rugoscopy. The uniqueness, overall stability and feasibility make palatal rugaean ideal forensic identification marker.Keywords: Rugoscopy, Personal identification, Gender, Marker

Molecular insights and oligonucleotide based targeted gene therapy against cancer

The thesis helps to unravel the function of T lymphoma invasion and metastasis protein (TIAM1) and nucleolin, a nucleolar protein in retinoblastoma tumorigenesis. Aptamer based targeted imaging; drug and gene delivery to retinoblastoma and epithelial cancer cells was attained. The work work finally opened up avenues for cancer stem cell targeting using aptamers, imaging of cancer cells using novel bio-orthogonal agent and use of aptamer for blocking the miRNA-17-92 cluster maturation

Fault diagnosis in aircraft fuel system components with machine learning algorithms

There is a high demand and interest in considering the social and environmental effects of the component’s lifespan. Aircraft are one of the most high-priced businesses that require the highest reliability and safety constraints. The complexity of aircraft systems designs also has advanced rapidly in the last decade. Consequently, fault detection, diagnosis and modification/ repair procedures are becoming more challenging. The presence of a fault within an aircraft system can result in changes to system performances and cause operational downtime or accidents in a worst-case scenario. The CBM method that predicts the state of the equipment based on data collected is widely used in aircraft MROs. CBM uses diagnostics and prognostics models to make decisions on appropriate maintenance actions based on the Remaining Useful Life (RUL) of the components. The aircraft fuel system is a crucial system of aircraft, even a minor failure in the fuel system can affect the aircraft's safety greatly. A failure in the fuel system that impacts the ability to deliver fuel to the engine will have an immediate effect on system performance and safety. There are very few diagnostic systems that monitor the health of the fuel system and even fewer that can contain detected faults. The fuel system is crucial for the operation of the aircraft, in case of failure, the fuel in the aircraft will become unusable/unavailable to reach the destination. It is necessary to develop fault detection of the aircraft fuel system. The future aircraft fuel system must have the function of fault detection. Through the information of sensors and Machine Learning Techniques, the aircraft fuel system’s fault type can be detected in a timely manner. This thesis discusses the application of a Data-driven technique to analyse the healthy and faulty data collected using the aircraft fuel system model, which is similar to Boeing-777. The data is collected is processed through Machine learning Techniques and the results are comparedPhD in Manufacturin

Development of tail rotor power analysis model with feasibility study of electrical tail rotor.

In recent years, there has been significant work undertaken by the aviation industry to increase the overall rotorcraft performance, and eventually, eliminate leak prone hydraulic fluids and to reduce CO₂ emissions. Even though a mechanical-gearbox-driven tail rotor has been extensively used in several applications, it comes at the expense of high life cost of the gearbox and shaft gear mechanism. This thesis concentrates on the developing a model to analyse the power requirement for the tail rotor drive and feasibility investigation of an electrical tail rotor to substitute the shaft geared system and the conventional tail rotor power transmission gearbox. A case study is conducted on the Sikosky UH-60A rotorcraft to assess the conventional tail rotor power requirement and Electrical systems. A mathematical model based on Rankine Froude’s momentum theory is created to analyse the power required to drive the anti-torque system, which could be adapted to any conventional drive train (with the main rotor and a tail rotor) rotorcraft. A mission profile and trajectory are created and implemented into Excel based mathematical model. The challenges in implementing electrical drivetrain (electrical generation, energy conversion and electric transmission) are briefly discussed in this thesis. Electrical load analysis database is generated to find the electrical load of the generator for the entire flight phases and utilised to up-scaled the generator to compensate the new load from Electrical tail rotor. The electrical powertrain system is designed with a Brushless DC motor attached to the tail rotor and the generator and the battery for redundancy purposes. The research thesis develops an understanding of current electric motor and battery technology to create a novel design of electric tail drive that increases the reliability of the helicopter system.MSc by Research in Aerospac

Genetics of mineral accumulation in potato tubers

As a major food source potato delivers significant levels of minerals to the human diet. The aim of this study was to understand the control over the mineral concentrations found in tubers. The three-dimensional patterns of mineral distribution in tubers give clues to the processes leading to storage in the tuber. Within the tuber flesh, calcium and phosphorus content decreased towards the centre of the tuber (on FW basis). The elements iron, magnesium, zinc, manganese, sulphur and chlorine were higher at the stem end, while potassium was higher at the bud end. Remobilisation of minerals within the tuber was evident after six months of cold storage. Mineral variation was explored in potato germplasm. Three diverse germplasm collections, the Commonwealth Potato Collection, the Phureja and Tuberosum Core Collection and the Neotuberosum Population demonstrated wide variation for tuber mineral concentrations, an interaction with tuber yield and, on multivariate analysis, consistent parallels between some minerals suggesting unsuspected shared processes affecting their concentrations. The 12601ab1 x Stirling tetraploid mapping population was used to identify QTls for tuber mineral concentration using REML analysis to account for local field variation. Transgressive segregation for tuber mineral concentrations was detected. The genetic map for this population was extended using DArT markers and QTLs were identified on all 12 linkage groups for all minerals studied. Two bulk segregant analyses were performed to add precision to the QTL analysis. One approach identified candidate genes on the potato genome sequence and used nearby SSRs to seek association in the tetraploid mapping population. A second approach used the variation present in the highly diverse Neotuberosum Population to identify DArT markers which were associated with the tails of the distribution of minerals. Using the latter approach, single superscaffolds containing candidate loci and trait-associated DArT markers could be aligned with a small part of mapping population QTLs, providing additional resolution

RNAi mediated Tiam1 gene knockdown inhibits invasion of retinoblastoma

T lymphoma invasion and metastasis protein (Tiam1) is up-regulated in variety of cancers and its expression level is related to metastatic potential of the type of cancer. Earlier, Tiam1 was shown to be overexpressed in retinoblastoma (RB) and we hypothesized that it was involved in invasiveness of RB. This was tested by silencing Tiam1 in RB cell lines (Y79 and Weri-Rb1) using siRNA pool, targeting different regions of Tiam1 mRNA. The cDNA microarray of Tiam1 silenced cells showed gene regulations altered by Tiam1 were predominantly on the actin cytoskeleton interacting proteins, apoptotic initiators and tumorogenic potential targets. The silenced phenotype resulted in decreased growth and increased apoptosis with non-invasive characteristics. Transfection of full length and N-terminal truncated construct (C1199) clearly revealed membrane localization of Tiam1 and not in the case of C580 construct. F-actin staining showed the interaction of Tiam1 with actin in the membrane edges that leads to ruffling, and also imparts varying invasive potential to the cell. The results obtained from our study show for the first time that Tiam1 modulates the cell invasion, mediated by actin cytoskeleton remodeling in RB

Spectral Imaging of Skin: Experimental Observations and Analyses

The emergence of compact optical spectral imaging technologies has motivated the study of their use in a variety of applications, including medical diagnosis and monitoring. In particular, large format CCD focal planes in conjunction with spectrally tunable devices offer enhanced spatial information together with visible and near infrared (NIR) spectroscopic data for the passive, noninvasive, measurement of human skin and near surface tissue characteristics. One such spectral imaging system was recently developed by mating a Liquid Crystal Tunable Filter (LCTF) together with a 2048x2048 silicon CCD focal plane. This system is capable of collecting more than 30 co-registered spectral images spaced every 10 nanometers and spanning 400 to 720 nanometers. This system combines the potential of near infrared diffuse reflectance spectroscopy with the high spatial resolution of traditional optical imaging techniques. Spectral images were acquired of portions of the hands and arms of several test subjects with a variety of features observable. The observations were collected in a light box under controlled illumination conditions. Images of a diffuse reflectance standard and instrument dark frames were collected to allow conversion of the raw images to spectral reflectance images. This paper presents examples of the spectral images collected, instrument characteristics and performance, and results of analysis algorithms applied to the data. Results also are shown for a new algorithm extracting the saturated oxygen hemoglobin fraction from these data

Spectral Imaging of Near-Surface Oxygen Saturation

A number of non invasive methods have been developed to characterize parameters in near-surface skin tissue; however, the work has usually been concerned with using either spectral or spatial information. This motivated our study in which both spatial and spectral data are used to extract features for characterizing the spatial distribution of near-surface oxygen saturation. This paper addresses combined physical and statistical models to retrieve the ratio of oxy- and deoxy-hemoglobin in tissues from data collected by an imaging spectrometer. To retrieve the oxygen saturation fraction from the data, algorithms from the literature using two or three wavelengths were compared to our new algorithm using the many more wavelengths (25 to 60) available in imaging spectrometer data, and noise reduction achieved through principal component transformations. In addition to the analysis of experimental spectral imagery, an oxygen saturation phantom of size 128x128 pixels was simulated. In the forward process, a reflectance image was constructed from an assumed oxygen saturation map and the absorption coefficients of oxy-hemoglobin, deoxy-hemoglobin, melanin and other chromophores. The reflectance data have 60 bands spanning 400 nm to 990 nm with 10 nm intervals in the spectral dimension. Varying amounts of white Gaussian noise was added to the reflectance data to simulate measurement errors in an actual experiment. In the backward process, an oxygen saturation image was reconstructed by applying the algorithm to study the effect of measurement error on the retrieved saturation fraction. The resultant images were evaluated by their mean squared error

Sequence-specific cleavage of hepatitis C virus RNA by DNAzymes: inhibition of viral RNA translation and replication

DNAzyme (Dz) molecules have been shown to be highly efficient inhibitors of virus replication. Hepatitis C virus RNA translation is mediated by an internal ribosome entry site (IRES) element located mostly in the 5' untranslated region (UTR), the mechanism of which is fundamentally different from cap-dependent translation of cellular mRNAs, and thus an attractive target for designing antiviral drugs. Inhibition of HCV IRES-mediated translation has drastic consequences for the replication of viral RNA as well. We have designed several Dzs, targeting different regions of HCV IRES specific for 1b and also sequences conserved across genotypes. The RNA cleavage and translation inhibitory activities of these molecules were tested in a cell-free system and in cell culture using transient transfections. The majority of Dzs efficiently inhibited HCV IRES-mediated translation. However, these Dz molecules did not show significant inhibition of coxsackievirus B3 IRES-mediated translation or cap-dependent translation of reporter gene, showing high level of specificity towards target RNA. Also, Northern blot hybridization analysis showed significant cleavage of HCV IRES by the Dz molecules in Huh7 cells transiently transfected with the HCV-FLuc monocistronic construct. Interestingly, one of the Dzs was more effective against genotype1b, whereas the other showed significant inhibition of viral RNA replication in Huh7 cells harbouring a HCV 2a monocistronic replicon. As expected, mutant-Dz failed to cleave RNA and inhibit HCV RNA translation, showing the specificity of inhibition. Taken together, these findings suggest that the Dz molecule can be used as selective and effective inhibitor of HCV RNA replication, which can be explored further for development of a potent therapeutic agent against HCV infection