Thesis Publications

The transportation of specific molecules across lipid membranes is an essential function of all living organisms and a large number of specific transporters and channels have evolved to carry out this function. One of the largest transporter gene families is the ATP-binding cassette (ABC). CFTR, Cystic fibrosis trans-membrane conductance regulator, is a member of this family and its mutation cause cystic fibrosis. In order to create more effective drugs to treat cystic fibrosis, understanding the mechanism of this disease and structure of CFTR will be needed. Therefore, obtaining the 3D structure will lead to a greater understanding of CFTR. Studying the structure of the C-terminal part of CFTR is the aim of this project. This study also allowed a comparison between killifish and human orthologs. By conducting the same conditions on human orthologs of the CFTR C-terminus, Killifish C-terminal was cloned into pET-28 a (cloning and expression vector), expressed in E.coli and purified using Talon immobilized metal affinity chromatography. The purified protein then characterized using MALDI-TOF analysis, and Circular Dichroism. Killifish gave a higher yield compared to human ortholog, which made it more suitable for further structural and functional studies.

Bioavailability (with high permeability and solubility) is important for effective therapeutic drugs. Nevertheless, in drug research, many drug molecules are of low permeability and solubility. Accordingly, in order to prolong the release and boost the bioavailability of these drug substances, new methods are required. A nanoparticle is a new solution to frame drug agents into nanoparticles. Two drugs fragments like furosemide (diuretic) suit to the BCS class IV and Amlodipine Besylate (calcium channel blocker) suit to the BCS class II in this study were co-encapsulated into PLGA nanoparticles by PVA as a surfactant. Normal particle dimension of these nanoparticles was found to be 275 nm with -12 mV zeta potential value. In house HPLC technique was developed for simultaneous estimation of these two molecules using CAN 5 C18-AR HPLC column with Phosphate buffer: CAN (62:38) as a mobile phase (1.0ml/min flow rate, 220nm detection) for entrapment efficacy study. Normal entrapment efficiency of Amlodipine and Furosemide were found to be 40% and 58%. Additionally, in vitro dissolution study was conducted in the phosphate buffer pH 7.4, and it was witnessed that 6% and 10% amlodipine and furosemide were released after 24 hours at room temperature condition at 100 rmp. From these results, it was concluded that these two molecules could be co-encapsulated in PLGA nanoparticles and below 15% relief of these two molecules after co-encapsulation in the PLGA nanoparticles showed the controlled release arrangement.

Austenitic stainless steels (ASS) represent the largest group of stainless steels and have maximum usage in industry. AISI 316L austenitic stainless steel is widely used as a structural material in chemical, petrochemical, power engineering and aviation industries owing to its good combination of mechanical properties, corrosion resistance and weldability. In view of industrial importance of this stainless steel, the proposed work would comprise of fabricating welded joints on 10mm thick AISI 316L using two different groove designs viz. Single-V groove and Narrow gap and submerged arc welding process. In view of the service applications that this alloy is subjected to, the joints will be subjected to thermal aging to high temperature of 750°C for 24 hours duration. The joints were thermally aged to study effects of precipitation at high temperature (750°C/24 hrs.) aging condition on different welds. For analyzing different aspects of these welds different specimens were extracted from the welded plates and were further subjected to metallurgical, corrosion and fatigue testing.The metallurgical testing were carried out via optical microscopy, ferrite content evaluation and microhardness measurements. Further, corrosion performance was evaluated using potentiodynamic scan for determining the pitting corrosion resistance of AISI 316L welds with different joint designs. The fatigue crack propagation behavior of different welds was determined through fatigue testing of above-mentioned welds. The results of corrosion and fatigue crack growth performance of AISI 316L welds with different joint designs and thermal aging were correlated with metallurgical observations. Mixed morphology of lacy and skeletal ferrite along with lower ferrite content and higher microhardness were observed for narrow gap butt weld as compared to single V-weld. Further, pitting corrosion resistance was also improved for joints prepared with narrow gap butt weld. The FCGR performance of narrow gap butt weld was also improved as compared to single V butt weld. Aging at high temperature reduced the pitting corrosion performance but increased the fatigue performance owing to accelerated precipitation in AISI 316L welds with different joint designs.

The port of Mombasa is one of the busiest ports along the East African coast because it serves the landlocked countries in the neighbourhood. With the increase in growth of trade in East and Central African countries, the volume of goods, with varying complexities of hazards and awkward weights requiring specialized handling equipment, passing through the port of Mombasa will increase. This presents high probability of occurrence of major accidents. Major accident may include explosion, fire, toxic chemical spill or even lifting equipment failure. This study focused on four key determinants of effective control to occurrence of major accidents namely: Safe systems of work, cargo handling equipment maintenance, training and risk assessment. The study was done adopting a stratified random sampling technique with a target population of 650 and a sample population of 248 determined using Slovin’s formula. The target population consisted of dockworkers majority of whom are ship clerks, tally clerks, lifters, signalers, crane operators, maintenance technicians and truck drivers. There was also middle level management like engineers, technologists, safety and environment officers. The questionnaires, interviews and observation checklist were used to collect data. Results showed 58.2% of the respondents had worked for the organization for more than ten years. The port was found to be a multi-stakeholder operations site with 20% of employees being contractors. A high percentage of 94.2% of respondents held the view that safe operations procedures would not help in control of major accidents in the port when jobs needed to be completed faster, showing the underlying poor safety culture levels in the organization.This could also mean that sometimes the procedures would be disregarded to get the job done. Cargo handling equipment seen in use at the port included: Cranes, container handlers, forklifts, bulk handling equipment. 89.8% of the respondents held the view that cargo handling equipment had potential to lead to occurrence of major accidents.Interview with respondents confirmed that there had been recent and past fatality and dangerous occurrences and incidents related to use of equipment. For the review period of Oct to Dec 2017, over 63% of (88 of 139) the accidents had occurred at the container terminal as compared to the conventional terminal probably because of less equipment used and less traffic compared to the container terminal. Most of the accidents were related to equipment failure and private trucks operated by contractors. Training gaps existed and in various contexts where 53.1% of respondents said they had not undergone any training or awareness on prevention of accidents or hazards despite operating in a potentially risky environment. There were no inclusion of major accidents prevention and awareness topics in the training curriculum reviewed and 82.5% of respondents felt that the training they had received had not given them the confidence required in terms of responding to or handling major accidents if they did occur in their workplaces. The extent of implementing actions and recommendations arising from risk assessment would take long due to delays or bureaucratic approval process, hence increasing risk exposure. It is recommended that a major accident control policy is developed and implemented and that topics in prevention of occurrence of major accident are included in the training curriculum.

The study examined the mentors? perception on the challenges and the opportunities encountered by the mentors while mentoring the undergraduate research project in colleges under Royal University of Bhutan (RUB) with special reference to Gedu College of Business Studies. The study has been motivated by the realization that some of the mentors are reluctant to take the undergraduate research groups. Therefore, it is important to find out what are some of the challenges and opportunities faced by the respective mentors in the process of mentoring the research projects. To make the study more authentic and realistic, purposive sampling had been used and personal interviews were conducted to collect data for the study. The data collected through personal interviews were analyzed thematically. The study intends to highlight the most challenging factors and try to provide suitable recommendations. The findings of the study entails that the most challenging part of mentoring is time management and lack of students? knowledge on research. Most of the respondents find it difficult to adjust their time for research due to their teaching workload. Nevertheless, the study also found out that they also get various benefits and opportunities in the process of mentoring.

Head teacher is a vital part of any school. A school works as an organization in which Head teacher, teachers and students play their role for its effective performance. Head teacher is responsible for designing the whole framework of school and implementing the educational plan to achieve the set goals. Head teacher and teacher relationship is an effective part of school administration. It does affect the effectiveness of school management and its performance. In this way, it also affects the results of the institutions. The good performance of school shows how much effective Head teacher and teacher relationship exists in school. In order to achieve the objectives of the study, a five-point scale was developed. It consisted of twenty-five statements for Head teachers as well as teachers of secondary schools. For each statement in the questionnaire, five options were given which were strongly disagree, disagree, neutral, agree and strongly agree. The respondents were asked to tick the one option among the given five according to their free will. The questionnaire was validated and pilot tested. The questionnaire was administered to the sample and responses were collected. The data collected through questionnaire was tabulated, analyzed and interpreted. The results of the study show that different school’s head teachers adopt different type of strategies in the same situation but their main aim is to run the system of school smoothly. They effectively play their role in motivating and facilitating the teachers for effective functioning of school.

Chronic obstructive pulmonary disease (COPD) has only recently been seen as a multi-systemic rather than a respiratory system disease. It is acknowledged that the inflammation which occurs and installs in COPD leads to remodeling of the airway, with consequent impaired pulmonary mechanism and obstructed air flow.