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The increasing use of permanent magnet motors in demanding high temperature environments has led to a renewed research interest into Sm₂CO₁₇ type magnets in recent years. This work has investigated key points in the commercial production route of a sintered magnet with composition Sm(Co\(_{0.7}\)Fe\(_{0.21}\)Cu\(_{0.07}\)Zr\(_{0.02}\))\(_{7.61}\), with an aim to establish if the current heat treatment route can be optimised. Through small alterations to Sm content, it was found that a high knee field (H\(_k \)) of ~1700 kAm\(^{-1} \) and high remanence (B\(_r\)) of 1.13 T could be achieved in a Sm(Co\(_{0.7}\)Fe\(_{0.21}\)Cu\(_{0.07}\)Zr\(_{0.02}\))\(_{7.77}\) sintered alloy, a particularly Fe rich composition, after quenching directly from the aging temperature. This suggests high remanence magnets, with good coercivity, could be produced without the requirement for the controlled 'slow cool', shortening production time per batch by ~7-10 hours. Strip casting was investigated as an alternative to ingot casting in the production of the starting alloy for sintered magnets. If a structure of large grains of the 1:7 phase could be produced, the homogenisation step would be unnecessary. A wheel speed of 1.6 ms\(^{-1}\) with an F8-grit textured wheel, did not produce a single 1:7 phase, and the grain structure was too fine. Grain coarsening heat treatments had limited success.

Road pavement design in Kurdistan is based on ASSHTO 1993. However, it seems not to be entirely satisfactory since it is unable to take full account of properties of local soils or those which have been stabilised. To address this, a design procedure applicable to different material and environmental conditions was developed. The associated research consisted of a suite of laboratory experiment allied to the development of a finite element model. The laboratory work was undertaken on three types of subgrade soils found in Kurdistan to determine their permanent deformation behaviour, UCS and resilient modulus for a range of moisture contents. The experimental investigation considered soils stabilised with 2%, 4% cement content and a combination of cement and lime with 2% cement plus 1.5% lime and 4% cement and 1.5% lime. The results were used to develop empirical equations to: (i) predict resilient modulus values of deteriorated modified soils as a function of different stabiliser contents and types; (ii) correlate resilient modulus values of soils with their UCS and stress state; (iii) determine the accumulation of permanent deformation in modified subgrade soils subject to weathering. These relationships, together with the developed finite element model were used to establish the design procedure.

The variation between surface and air temperature within a city and its surrounding area is a result of variations in surface cover, thermal capacity and 3-dimensional geometry. This study examines the spatiotemporal formation of the daytime Surface Urban Cool Island (SUCI) and night-time Surface Urban Heat Island (SUHI) effect in Erbil, Iraq, as a case study for cities in semi-arid climates more generally. It furthermore quantifies the influence of rapid urban expansion on the urban heat/cool island effect over a 20 year period. Satellite images acquired by Landsat 4, 5, 7 and 8 between 1992 and 2013 are used to retrieve Land Surface Temperature (LST). Normalised Ratio Scale (NRS) is applied to the multi-mission Landsat data, which is used to adjust the temperature range for different acquisition times of images within the same temporal range. In addition, LST data from the Moderate Resolution Imaging Spectroradiometer (MODIS) on board Aqua and Terra from January 2003 to December 2014 are analysed. In order to establish the drivers of the observed patterns of LST and SUCI/SUHI, the relationships of LST with wetness, greenness, NDVI, soil moisture and other variables are assessed. The results indicate that during the daytime in summer, autumn and winter, densely built-up areas had lower LST acting as cool islands (SUCI) compared to the non-urbanised area around the city. In contrast, at night-time, Erbil experienced higher LST and demonstrated a significant SUHI effect. The mean LST of the newly urbanised and vegetated areas between 1992 and 2013 decreased by 2.28°C and 7.29°C respectively. Soil moisture (wetness) is the main marker of the SUCI/SUHI effect, whilst urban expansion may cause a decrease of daytime LST in dry climate zones. The NRS method is appropriate for detecting temperature trends greater than 2°C in Landsat data.

This thesis is principally concerned with effcient energy consumption in wireless sensor networks from two distinct aspects from a theoretical point of view. The thesis addresses the issue of reducing idle listening states in a restricted tree topology to minimise energy consumption by proposing an optimisation technique: the extra-bit technique. This thesis also focuses on showing lower bounds on the optimal schedule length, which are derived for some special cases of the tree, such as a single chain, balanced chains, imbalanced chains, three and four level k-ary trees and Rhizome trees. Then, we propose an algorithm which can exactly match the lower bound for a single chain, balanced chains and Rhizome trees individually and which is a few steps away from the optimal solution for imbalanced chains. Finally, we propose the use of two frequencies to further save energy and minimize latency. Recent research has shown that significant energy improvements can be achieved in WSNs by exploiting a mobile sink for data collection via single hop communications. A mobile sink approaches the transmission range of sensors to receive their data and deposit the data at the base station. The thesis, as a second problem, focuses on the design issues of an energy efficient restricted tour construction for sink mobility. We propose two different techniques. The first one is heuristic and uses a criterion based on maximum coverage and minimum energy consumption called the "max-ratio". Although its time complexity is polynomial, this heuristic algorithm cannot always produce a good solution. As a result, we propose the sec- ond algorithm. Despite the time complexity of the second algorithm being pseudo polynomial, the optimal solution can be found if one exists. For each algorithm men- tioned, two scenarios are taken into account with regard to the transmission. In the first scenario, one assumes that there is no upper bound on the transmission range while in the second setting the nodes can adjust their transmission range between 0 and the maximum range. The algorithms have been implemented and simulated in Matlab.

The present research explores translation procedures and strategies employed in current English-Kurdish translation of written media discourse. It is located within Toury’s (1995/2012) framework of Descriptive Translation Studies (DTS). The research sets out to contribute to Translation Studies, specifically the study of journalism translation. Despite the fact that translation has been an inseparable part of media and journalism activities for decades, if not centuries, the systematic study of media translation is as recent as the turn of the new millennium. This study focuses on English-Kurdish translation of written media discourse, which has remained largely under-researched. The study precisely sets out to identify the patterns of translation procedures and the overall translation strategies prevalent in Kurdish translations of English journalistic texts. To do so, a composite model is formulated based on an integration of three influential taxonomies of translation procedures proposed by Vinay and Darbelnet (1958/1995), Newmark (1988) and Dickins, Hervey and Higgins (2002). The model is applied to a set of 45 journalistic texts translated from English into Kurdish, which altogether make a corpus of approximately 75,000 words. A comparative analysis of ST-TT coupled pairs is carried out to identify patterns of translation procedures at the linguistic as well as cultural level. To look at the findings from a different perspective, a research questionnaire is also conducted with English-Kurdish translators working in the Kurdish media. Based on the patterns of translation procedures, the overall transition strategies are then determined. Analysis in Chapters 6, 7 and 8 leads to the conclusion that literal translation, borrowing and omission are the most frequent translation procedures at the linguistic level, and cultural borrowing, cultural redomestication and calque are the most frequent at the cultural level, keeping in mind that the notion of cultural redomestication constitutes the present study’s major contribution to Translation Studies. As for the overall strategies, semantic translation is the predominant orientation of the linguistic aspect of the translation, while foreignization is the predominate orientation of the cultural aspect of the translation.

Intercultural learning in UK tertiary education is largely operationalised as a universal or implied term. The focus generally is on the internationalisation of the curriculum, which has mainly developed in response to the recruitment drive of international students to local campuses over the last two decades. Within this market-centric context, a stronger educational rationale has been advocated, which in recent years has promoted a ‘pedagogy of recognition’ (Caruana and Spurling, 2007, p. 66), rejecting international students’ automatic assimilation to the prevalent socio-academic culture. Although international students are regarded as ‘a resource for learning’ in this context (Ryan, 2011, p. 633), a praxis grounding of how to facilitate this ostensibly more progressive approach is not readily apparent. In this research project with international students and staff at my former workplace, a private tertiary education college in London, I investigated in what ways cultural diversity is understood and interpreted pedagogically. The research aim was to explore what constitutes lived experiences of intercultural learning, in order to inform my praxis choices with regard to a pedagogy of recognition. A bricolage approach, comprising critical pedagogic theory and hermeneutic phenomenological methodology, was adopted to facilitate the project embedded within this distinct socio-economic educational context, further involving 52 online questionnaires and 38 semi-structured interviews with international students and staff of the college during summer 2013. The research contributes to current internationalisation discourse by proffering a theory/practice understanding of a pedagogy of recognition with regard to fostering intercultural learning. It identifies the importance of including an embodied dimension in pedagogic praxis, whereby intercultural learning among participants is approached with reference to a safety/risk axis. Specifically, it suggests alerting students to learning opportunities that might be realised from intercultural interactions without predetermining these, considering that intercultural learning is always more complex than teachers’ rationales and deeply ingrained in students’ own life projects and the wider political arena. Consequently, I argue that possibilities for human creativity among learners, rather than mere celebration of cultural diversity or assumed shared outcomes, become available.

The structure, kinetics, and interactions of the conserved 16mer and 15mer RNA motifs of the internal ribosome entry site (IRES) of the Foot-and-Mouth Disease virus (FMDV), have been investigated by homonuclear and heteronuclear NMR techniques. The 16mer RNA is endowed with a classic GNRA tetraloop motif, which is essential for IRES activity and the 15mer RNA motif is a potential tetraloop receptor. We have determined three high resolution NMR solution structures of the 16mer apo-RNA, the 16mer Mg2+ RNA complex and the 15mer apo-RNA with RMSDs of 0.17Å, 0.16Å and 0.35Å, respectively. The high precision of these NMR structures was achieved by including a large number of NMR experimental restraints, derived from NOEs and coupling constants, and validating them using the MolProbity program. The 16mer RNA structure comprised of six base pairs with a GUAA tetraloop and the 15mer RNA structure comprised of four base pairs and a large heptaloop; this is the first heptaloop to be studied by NMR.Addition of Mg2+ to the 16mer apo-RNA caused selective chemical shift changes to the stem G177 and loop G178 imino proton resonances, suggesting Mg2+-induced conformational change to the GUAA tetraloop. This was supported by a significant chemical shift change to the selectively 19F-labelled loop U179 in the 5-FU 16mer RNA. Furthermore, variable temperature experiments revealed retarded imino proton exchange for the stem and loop imino protons, demonstrating the enhanced thermodynamic stability conferred by Mg2+. This enhancement in stability was confirmed by measuring the imino proton exchange rates for the 16mer apo-RNA and the 16mer Mg2+ RNA complex. Analysis of the 16mer apo-RNA and its Mg2+ RNA complex NMR solution structures revealed that Mg2+-induced structural changes to the GUAA tetraloop act to stabilise the loop via stronger base stacking and intramolecular interactions. Fascinatingly, we discovered that Mg2+ ions provide increased stability required for the formation of a G.A sheared base pair in the GUAA tetraloop. RNA-RNA interactions between the 16mer and 15mer RNAs and their fluorinated analogues were studied by NMR spectroscopy. Small changes to chemical shift and linewidth of proton peaks in the non-fluorinated RNA-RNA complex provided evidence for a weak interaction between the loop of the 16mer RNA and the stem of the 15mer RNA. 19F-NMR experiments revealed additional peaks for the 19F-labelled U179 of the fluorinated 16mer/15mer RNA complex providing further good evidence of RNA-RNA interaction. The NMR structures of the conserved RNA motifs and their interactions have yielded important information in understanding the properties and behaviour of RNA. This will provide the first stepping stone in understanding the IRES mechanism and its use in antiviral therapy and biotechnology.

γ‐secretase is a membrane‐bound proteolytic complex, formed by nicastrin, APH1, presenilin and pen‐2, which cleaves over sixty known substrates, including Notch and Ecadherin, thus regulating cellular processes such as proliferation and adhesion. High levels of nicastrin have been demonstrated in 47.3 % (n=1050) high tumour grade breast tissues, whereas it is absent in 100% normal human breast (n=40). Although the mechanism for nicastrin up‐regulation in breast cancer is unknown, preliminary data suggests posttranscriptional regulation. Therefore, γ‐secretase is an important therapeutic target in breast cancer. GSI1, a commercial γ‐secretase inhibitor is cytotoxic exclusively for breast cancer cell lines, whereas non‐tumourigenic breast cells are not affected. GSI1 triggers G2/M arrest, culminating in apoptosis through down‐regulation of XIAP, Bcl‐2, Bax and Bcl‐XL in breast cancer cells. In addition, similar cytotoxicity has been found in a panel of cell lines derived from several types of cancer. We discuss whether the cytotoxic effect of GSI1 in breast cancer cell lines is mediated through inhibition of γ‐secretase or the proteasome. RNA interference of individual γ‐secretase components indicates that NCSTN knock‐down elicits 55% cell growth reduction, whereas knock‐down of the other complex components does not inhibit cell growth to the same extent. In addition, NCSTN siRNA reduces invasion in breast cancer cells. Disseminated and circulating tumour cells (CTCs) are clinically used as indicators of metastasis. Nicastrin has been found to be expressed by a rare population of cells in bone marrow aspirates and in CTCs from breast cancer patients with high risk of relapse. Thus, from the pharmacological point of view, nicastrin represents a novel therapeutic target. In addition, it is a novel biomarker for breast cancer with potential diagnostic applications.

I develop and test models of household behavior where household members behave non-cooperatively. I view marriage as a contract between husband and wife. This approach stresses the importance of household members to make enforceable contracts or agreements with each other. The reason why actions taken by individuals within the household are non-contractible is because they are non-verifiable to third parties outside of the household. This approach has two major appeals. First, whenever non-contractible choices are subject to renegotiation, dynamic inefficiencies arise. This helps provide a theoretical underpinning to a growing body of empirical evidence that suggests households do not always make efficient decisions. Second, thinking of marriage as a contract leaves scope for individual household members to have different preferences and face different constraints. As households renegotiate over the division of the surplus from marriage, individual threat points and outside options still play a role in determining the allocation of resources within the household. I apply this framework to three settings - investing into fertility, investing into child quality, and decisions to marry and divorce.

The main aim of this research was to examine predictors of both objective (salary). and subjective (perceived) career success. Three sets of predictors were examined: (1) individual attributes, (2) organisational opportunity structures and (3) career strategies. It was expected that a different pattern of variables would predict objective and subjective career success. In addition, the mediating role of career strategies was examined. It was expected that individual attributes and opportunity structures would be positively related to the use of career strategies, and that these strategies would be positively related to career success. Cross-sectional survey methodology was employed to collect data from a sample of 723 full-time employees in administrative/ technical, academic and managerial posts at several British universities. According to expectations, a different pattern of variables was related to objective and subjective career success. The strongest predictors of objective career success were education, organisational size and extended work involvement. In contrast, the strongest predictors of subjective career success were internal labour market perceptions of structured career progression and employment security. Separate analyses by gender and occupational group revealed a similar difference in the profile of predictors of objective and subjective career success. Overall, the results suggested that the variables that related to objective career success were often not the same as those related to subjective career success. This was taken as support for the main theme of this research that objective and subjective career success, although related, are substantially distinct concepts. Contrary to expectation, however, the results provided limited support for the mediating role of career strategies in the relationship between individual attributes, organisational opportunity structures and career success (objective and subjective). Only individual attributes (education and work centrality) were positively related to the use of career strategies (extended work involvement, selfpromotion and networking), and these strategies in turn were positively related to objective or subjective career success. However, the mediating role of career strategies was weak, albeit statistically significant. A number of limitations, mainly regarding the cross-sectional nature of the study, are discussed. Educational and organisational implications of the findings are suggested. Finally, a two-dimensional model of career success is proposed, incorporating the findings of the present research with reference to the predictors of objective and subjective career success, together with suggestions for further research.

This thesis is concerned with Bayesian forecasting and sequential estimation. The concept of multiple discounting is introduced in order to achieve parametric and conceptual parsimony. In addition, this overcomes many of the drawbacks of the Normal Dynamic Linear Model (DLM) specification which uses a system variance matrix. These drawbacks involve ambiguity and invariance to the scale of independent variables. A class of Normal Discount Bayesian Models (NDBM) is introduced to overcome these difficulties. Facilities for parameter learning and multiprocess modelling are provided. Unlike the DLM's, many limiting results are easily obtained for NDBMM's. A general class of Normal Weighted Bayesian Models (NWBM) is introduced. This includes the class of DLM's as a special case. Other important subclasses of Extended and Modified NWBM's are also introduced. These are particularly useful in modelling discontinuities and for systems which operates according to the principle of Management by Exception. A number of illustrative applications are given.

In this dissertation, we consider estimation procedures for the linear model when the observations are replicated but the error variances are unequal. The aim of this research was to consider several standard methods for parameter estimation, namely Ordinary Least Squares, Weighted Least Squares, and Maximum Likelihood and to compare these with newly developed procedures. These new techniques included the use of a prior likelihood function to induce "shrinkage" towards a common value among the estimators for the error variances and procedures based on preliminary tests of the hypothesis of variance equality. Both an overall test of equality and a multiple comparison method were considered. In addition, variance estimates based on MINQUE (Minimum Norm Quadratic Unbiased Estimator) were investigated. The MINQU estimators tend to "stretch out" the variances and were found to be unsatisfactory. The performance of the above-mentioned approaches was investigated both through asymptotic theoretical results and small samples simulation studies. The results from these two approaches were found to be in broad agreement. Overall, the multiple comparison and prior likelihood procedures appear to perform best, but the prior likelihood depends upon the availability of satisfactory prior information. So the multiple comparison procedure appears to be the most effective technique in general. A further study was also conducted to examine the effects of "errors-in-variables." In general it is found that maximum likelihood is superior to ordinary least squares and weighted least squares only if a large number of replicates is used.

The overall aim of the present investigation is to adopt a fundamental approach towards the identification, measurement and modelling of the effect of pre- and post-processing upon shot-peening residual stresses. At present this is carried out in an ad hoc fashion with little understanding of the fundamental properties which are being affected by these treatments and of how these basic properties influence product performance and determine (the peening) process parameters. Indeed, current concern of reliability and efficiency of machinery alone justifies the widespread interest in the present investigation. The specific objectives arising from the above overall aim can be summarised as follows: (i) to identify, measure and model the effect of pre-processing upon the locked-in residual stress field and surface morphology of a prospective peening component, (ii) to identify, measure and synthesize the effect of shot-peening treatment upon the resulting stress field and surface profile of the treated component, (iii) to identify, measure and model the effect of post-processing upon the aforementioned parameters, and (iv) to examine the effect of residual stresses and incomplete-coverage upon ultimate product performance. Consideration of the surface profile will be accounted for in the analysis. The outcome of these investigations should provide the foundation necessary for process control and optimisation of working surfaces of components currently employed in aerospace, automotive and power generation industries. Accordingly a number of investigations will be carried out, in parallel, to highlight these effects. In view of the large number of variables involved in these processes, we focus our attention to the following: for pre-processing, controlled turning was selected and for post-processing, controlled grinding was selected. Residual stress measurements were performed by the centre hole air-abrasive off-centre rotating nozzle method, and whenever possible, the results were verified by other methods such as X-ray diffraction and etching. An experimental rig was designed, built and commissioned to allow for locating different sizes and shapes of cylindrical and flat components accurately near the 'drilling head'. The surface topography was measured, using a motorised stage and a profilometer of the stylus type. This arrangement enabled the three dimensional determination of treated surfaces. The materials investigated were typical of aircraft alloys: steel 817M40 and aluminium 7075, which were provided by a major landing-gear manufacturer (Dowty Rotol) . In order to examine the effect of residual stresses and surface profile upon ultimate product performance, fatigue tests using electro-hydraulic servo-controlled test equipment were used to evaluate the effect of the treatment upon the fatigue life and relaxation of residual stresses. Both complete and incomplete coverage were considered in the analysis. The results of the work show that pre-processing can induce unfavourable tensile residual stresses, which are detrimental to the fatigue life of the component. They also show that peening residual stresses play an important role ~n negating these tensile residual stresses. Effects of surface profile due to the pre-treatment also indicated a major influence on the success of the treatment, and upon the selection of the appropriate peening parameters. As for post-processing, it was shown that the residual stresses varied linearily with depth removed and remained significant even after 50 percent of the arc height had been removed from the component.

In completely specified models, where explicit formulae are derivable for the probabilities of observed events, the method of maximum likelihood has come to be the most widely employed method of estimation due to its optimal asymptotic properties. We discuss this method along with a review of the theory in Chapter 1. There is also some introductory material on asymptotic theory included in the first part of this chapter. There is currently growing interest in the use of estimating equations, other than those based on a full likelihood specification, for estimating parameters. In many cases this approach is particularly useful because the true likelihood is unknown or intractable. For example, maximum quasi-likelihood estimation is widely applied via the GLIM computer package. It is therefore of interest to examine the efficiency of such alternative methods relative to maximum likelihood. This is the subject of the present study in which a certain class of estimating functions is applied to some common data analysis situations. In Chapter 2, we discuss the previous development of these methods and their asymptotic properties, in particular the asymptotic variances of the resulting estimators. We consider models from widely used families, of both exponential and non-exponential types, to compare the asymptotic efficiencies of the methods discussed in Chapter 2. In Chapter 3, we compare the efficiencies, relative to MLE, in the case of independently identically distributed (iid) observations. In the first part we consider the exponential family models, and in the second part the non-exponential family models. Chapters 4 and 5 are concerned with similar comparisons for the non-iid case. Chapter 4 presents results when the models are taken from the exponential family, and in Chapter 5 the results are compared for non-exponential family models. Two types of situations, (i) when some parameters are assumed known, and (ii) when all parameters are unknown, will be considered. In the first case all the methods perform well, but in the second case a singularity problem removes two of the methods from comparison. In Chapter 6 we suggest further investigations for the estimating equations and connections between the methods are developed in some cases. The concluding results of previous chapters are also examined in detail.

Optical methods are employed in various fields from communications to space research to improve the system performance. Each application uses different properties of light and light-matter interaction. For example, ultra-high frequency nature of light is desirable in applications like ranging and velocimetry to increase the resolution. On the other hand, in the telecommunication industry, ultra-wide bandwidth of the fibers is utilized with time and wavelength multiplexing techniques that make Gigabit internet possible today. Such multiplexing techniques are also useful in photonic assisted analog to digital converters (ADC) that multiply the sampling rates of electronic ADCs. Additionally, ultra-low (

Dispersive Fourier Transform (DFT) is a measurement technique that facilitates wavelength to time mapping through optical dispersive elements with large and linear group velocity dispersion (GVD) such as dispersive fibers or chirped fiber bragg gratings (CFBG). This technique has been applied to several scientific and industrial applications such as analog to digital converters to increase effective sampling rates, spectroscopy to enable single-shot real-time spectral measurements, optical arbitrary waveform generation, and real time imaging to capture fast dynamic processes.In this work, Dispersive Fourier Transformation and its application on real time imaging are investigated. We demonstrated a fast dispersive laser scanning system that can achieve horizontal scanning through Raman amplified DFT and diffraction grating system and vertical scanning by employing MEMS based digital micro mirror arrays technology. The proposed technique employs real time dispersive imaging system, which captures spectrally encoded images with a single photodetector at pulse repetition rate via space-to-time mapping technology. Wide area scanning capability is introduced by using individually addressable micro mirror arrays as a beam steering device.Experimentally, we scanned ∼20mm2 at scan rate of 5kHz with ∼150μm lateral and ∼160μm vertical resolution that can be controlled by using 1024x768 mirror arrays. With the current state of the art MEMS technology, fast scanning up to 32.5kHz scan rate and resolution down to single mirror pitch size of 10.8μm is also achievable. Moreover, we investigated and demonstrated the ideas to improve the system to achieve larger area scan with faster scan rates and higher resolution while optimizing power.

Integrated temperature sensors play an important role in enhancing the performance of on-chip power and thermal management systems in today's highly-integrated system-on-chip (SoC) platforms, such as microprocessors. Accurate on-chip temperature measurement is essential to maximize the performance and reliability of these SoCs. However, due to non-uniform power consumption by different functional blocks, microprocessors have fairly large thermal gradient (and variation) across their chips. In the case of multi-core microprocessors for example, there are task-specific thermal gradients across different cores on the same die. As a result, multiple temperature sensors are needed to measure the temperature profile at all relevant coordinates of the chip. Subsequently, the results of the temperature measurements are used to take corrective measures to enhance the performance, or save the SoC from catastrophic over-heating situations which can cause permanent damage. Furthermore, in a large multi-core microprocessor, it is also imperative to continuously monitor potential hot-spots that are prone to thermal runaway. The locations of such hot spots depend on the operations and instruction the processor carries out at a given time. Due to practical limitations, it is an overkill to place a big size temperature sensor nearest to all possible hot spots. Thus, an ideal on-chip temperature sensor should have minimal area so that it can be placed non-invasively across the chip without drastically changing the chip floor plan. In addition, the power consumption of the sensors should be very low to reduce the power budget overhead of thermal monitoring system, and to minimize measurement inaccuracies due to self-heating. The objective of this research is to design an ultra-small size and ultra-low power temperature sensor such that it can be placed in the intimate proximity of all possible hot spots across the chip. The general idea is to use the leakage current of a reverse-bias p-n junction diode as an operand for temperature sensing. The tasks within this project are to examine the theoretical aspect of such sensors in both Silicon-On-Insulator (SOI), and bulk Complementary Metal-Oxide Semiconductor (CMOS) technologies, implement them in deep sub-micron technologies, and ultimately evaluate their performances, and compare them to existing solutions.

Pre-harvest sprouting (PHS) in cereal crops is generally associated with high levels of late-maturity aplha-amylase activity (LMAA). Alpha-amylase is one of the enzymes that occurs naturally in all wheat (Triticum aestivum L.) and is activated during the germination or sprouting process. Its activity can quickly break down starch and convert into free sugar molecules, resulting in reduced end-products quality. A semi-micro assay procedure was developed to quantify LMAA in spring wheat. The assay enables a single individual realistically to screen at least 120 samples each day and it is therefore suitable for use in a high-throughput breeding program. This proposed alternative to prior assays of LMAA uses at least two-third fewer reagents, as a result, it costs approximately $1 USD/data point. An international collection (IC) of eighteen spring wheat genotypes and a separate set of fifteen spring wheat cultivars adapted to South Dakota (SD) were evaluated for LMAA over five and thirteen site-year environments, respectively. A GGE model and a mixed linear model approach MINQUE were used to analyse the datasets. Broad-sense heritability for LMAA was higher among cultivars adapted to SD (53%) when compared to the IC genotypes (49%). Significant genetic effects predicted genotypes, such as, ‘Lancer’, ‘Chester’ and ‘LoSprout’ from IC, as well as ‘Alsen’ and ‘Forefront’ from SD could best be used as parents to develop PHS resistant genotypes with low levels of LMAA. Stability analysis using an AMMI bi-plot exhibited that Chester, Lancer and ‘Advance’ were the most stable across environments. A crossing population was developed by hybridizing parents with high- and with low levels of LMAA. The parents and their progeny in the F2 and in F3 generations were evaluated for LMAA. Datasets were analysed using the R software package ‘qgtools_1.0’ integrated with an additive-dominance genetic model and a MINQUE approach. The narrow-sense heritability for LMAA was found to be 12%. Significant negative additive effects for parents revealed that ‘Lancer’ and ‘Chester’ are good general combiners, and significant negative dominance effects and best-parent heterosis for hybrids showed specific hybrid combinations, such as, ‘Chester’/‘Kinsman’, ‘Lerma52’/‘Lancer’, ‘Lerma52’/‘LoSprout’ and ‘Janz’/‘Seri-82’ would produce progeny with low expression of LMAA.

Although the widespread use of biomaterials has resulted in significantly improved quality of life and patient survival, biomaterial-associated infections (BAI) remain a vital concern and treatment options are limited. In this study the ability of a novel antimicrobial peptide (AMP) melimine to prevent bacterial colonisation of contact lenses when covalently attached to the material surface was examined against a range of ocular clinical isolates. Various sequences derived from melimine were also analysed to determine if activity comparable to the parent peptide could be achieved with a shorter sequence. The solution mechanism of melimine was studied using circular dichroism and fluorescence spectra in membrane mimetic solvents and the interactions of melimine with bacterial membranes was examined using scanning electron, fluorescence and Atomic force microscopy. Perturbation of membrane integrity was tested by measurement of melimine mediated dye release from bacteria. Additionally, mechanism of action of surface bound melimine and a shorter derivative (melimine 4) was explored. Melimine and melimine 4 covalently-bound to contact lenses effectively reduced adhesion of clinically relevant bacterial species. In solution, melimine assumes a predominantly random coil conformation but when it is solubilised in SDS micelles, which are bacterial membrane mimetic, the -helical content increases to approximately 40%. A major effect of melimine was on the integrity of the cytoplasmic membrane for both P. aeruginosa and S. aureus. However, for P. aeruginosa the rapid loss of cytoplasmic membrane integrity correlated directly with loss of cell viability, while for S. aureus maximal dye release was obtained at concentrations where there was no significant loss of viability. There have been few studies to date investigating differences in the action of cationic peptides towards Gram-positive and Gram-negative bacteria. For covalently-bound peptides displacement of cations on bacterial surfaces and damage to cytoplasmic membrane resulted in loss of cell viability. These results indicate that the melimine and its shorter derivative melimine 4 are excellent candidates for further development as coatings to prevent bacterial colonisation of contact lenses and biomaterials. Further, mechanistic differences between Gram-negative and Gram-positive bacteria may further inform design of novel peptides with improved broad-spectrum activity.

The purpose is to isolate a natural compound, which shows a high activity against Candida albicans, from plant, Vincetoxicum stocksii. Bio-Assay, Thin layer Chromatography, Column Chromatography, TLC bio Assay, and other extraction techniques are used in order to isolate the active compound. First, bio assay technique is carried out on the crude gum. Next, several flash chromatography columns are carried out in order to isolate the target compound, which has a Rf value of ~0.53 in 10:1 DCM/methanol solvent mixture. The TLC bioassay technique is also carried out in order to confirm the hypothesis that the target compound is indeed active.

This thesis comprises four papers on the economics of networks. The first provides a survey of methods for econometric work with networks, summarising what is known in the economics literature, and incorporating methods from other fields including mathematics, computer science, and sociology. The second explains why informal insurance networks are able to provide consumption smoothing, but not credit for investment. It develops a dynamic contracting model to explain the difference in these motivations, generates from this a number of testable predictions, and then provides evidence in support of the model using data from Bangladesh. The third examines the trade-off between economic and cultural incentives for migrants. It develops a model of network formation combined with a game-on-a-network, to capture this trade-off. The model's predictions are then tested using data from US censuses in the early 1900s. The fourth studies the impact of tax audits by HMRC, the UK tax authority, on the future tax reporting behaviour of self-assessment taxpayers. It shows that income sources which are not also reported by a third party are more likely to be initially underreported, and that being audited increases future reports for a number of years. Future work in this area will study the spillover effects of the audits onto taxpayers connected to those who are audited, where networks of connections can be measured by sharing a place of residence, place of work, being partners in a common business, and sharing a common accountant.

This thesis presents an analysis of the determinants of public sector productivity in the Federal Government of Nigeria. The first chapter introduces the thesis, with an emphasis on the creation of measurement tools and methods for, and the collection of, the data that acts as the foundation of the contribution of my thesis work. The second chapter studies how management practices that bureaucrats in the Nigerian Civil Service operate under, correlate to the quantity and quality of public services delivered. For each of 4700 projects, I have hand coded independent engineering assessments of each project's completion rate and delivered quality. I supplement this information with a survey to elicit management practices for bureaucrats in the 63 civil service organizations responsible for these projects, following the approach of Bloom and Van Reenen [2007]. I find that management practices matter: a one standard deviation increase in autonomy for bureaucrats corresponds to significantly higher project completion rates of 18%; a one standard deviation increase in practices related to incentives and monitoring corresponds to significantly lower project completion rates of 14%. I provide evidence that the negative impacts of practices related to incentive provision/monitoring arise because bureaucrats multi-task and incentives are poorly targeted, and because these management practices capture elements of subjective performance evaluation that further leave scope for dysfunctional responses from bureaucrats. The backdrop to these results, where 38% of projects are never started, implies there are potentially large gains to marginally changing management practices for bureaucrats. The third chapter studies the causes and consequences of interactions between politicians and bureaucrats in the Nigerian Civil Service along two key margins: which bureaucrats a politician delegates the delivery of public projects to, and the incentives that politicians provide to those bureaucrats. To investigate these issues, I combine data on the political careers of politicians and measures of their interactions with bureaucrats with the data presented in my first chapter. I find that politicians facing high levels of political competition are more likely to (1) delegate the implementation of public projects in their constituency to more autonomous organizations; and (2) provide informal incentives to bureaucrats in those organizations. Guided by a moral hazard model, I assess the separate impacts of the delegation and incentive margins using an instrumental variables strategy. I find that delegation to more productive bureaucrats is the key channel through which politicians improve the bureaucracy's output when faced with high levels of political competition. The results have implications for the design of organizations that regulate politicians' interactions with the bureaucracy. The final chapter presents some concluding comments.