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This thesis contains three chapters on social and economic determinants of health. The first chapter investigates the causal effects of education on mental health. To address the endogeneity issues of education, the study uses Instrumental Variable strategy where actual years of education are instrumented by cohort-specific compulsory schooling years and its interaction with various childhood condition dummies. The estimates on the causal effects are sensitive to the choice of additional instruments. While majority of estimates suggest that there are no or only limited causal protective effects of education on mental health, the possibility of negative effects remains. The strong positive association between education and mental health could be explained by unobservable individual characteristics that affect education and mental health in the same direction. The second chapter studies whether more generous maternity leave protection in duration and payment can help decrease the incidence rates of pregnancy loss or termination (induced abortion, miscarriage and stillbirth) in low- and middle-income countries. Using a quasi-Difference-in-Differences approach, the study provides some evidence that increasing the generosity of maternity leave has the potential to reduce, in particular, the probability of induced abortion or miscarriage. The effects are stronger for Asian mothers who are working, mothers who have higher educational attainment and prestigious occupations, and mothers who were aged below 21 or above 30 at the realization of pregnancy outcomes. The last chapter explores how early life exposure to adverse shocks negatively affects the anthropometric outcomes of the second generation in Sub-Saharan African countries. The study reveals compelling evidence that mother's experience of negative rainfall shocks, particularly excessive drought, from in-utero to early adolescence significantly increases the probability that their offsprings suffer from impaired growth during early childhood. The effects are mainly driven by households residing in the rural areas and children who are located at the lower end of anthropometric distribution. There is also evidence that mothers' early life experience of negative rainfall shocks led to disadvantages in a variety of welfare outcomes persisting into marital households, which potentially contribute to next generation's underperformance in early life growth measures.

Nanoscale materials usually present strikingly different properties in comparison with their bulk counterparts, such as quantum size effects, surface plasmon resonance (SPR). To explore new properties as well as for novel applications, nanomaterials are being extensively investigated. This project investigates the interactions of electromagnetic fields with nanoscale materials, particularly gold nanoparticles (GNPs), over a wide range of frequency bands, including static field, 261 kHz, 13.56 MHz, 2.45 GHz, millimetre wave, THz, and the visible light. Especially, the efforts have been devoted to the study of heating effect of GNPs in association with potential biomedical applications. To explain the electromagnetic heating of GNPs, dielectric properties of GNP dispersions has been studied from 100 MHz to 20 GHz, as well as in the millimetre wave and THz ranges. The static field induced effects on the size distribution of GNPs has also been examined using ultra-violet spectroscopy and correlated to SPR. It has been revealed that purified GNPs cannot increase the specific absorption rate substantially at whichever frequency points of 261 kHz, 13.56 MHz, or 2.45 GHz. However, a greater temperature rise has been observed in the impurified GNP dispersions compared to deionisedwater, after 10 min RF treatment at 13.56 MHz. The measurements on dielectric properties show that impurified samples have much higher effective conductivity than that of deionised-water, while the conductivity change of purified ones is very small and not detectable within the measurement accuracy. This observation supports that the heating effect of GNP dispersions is mostly contributed by the impurities and disproves that GNPs can increase the specific absorption rate significantly. The magnetic field heating at 261 kHz suggests that GNPs have very weak magnetic properties. It has been found that a static field can change the size distribution of GNPs. Up to 2 THz, it is measured that the dielectric properties of GNP dispersions have no convincing change compared to deionised-water, implying that the electromagnetic heating of GNP below 2 THz may be insignificant. In addition, it is confirmed that GNPs have strong absorption in the visible light range due to SPR.

A series of binary ligand complexes [ReCl_6-n(py)_n]^z (where n=0 to 6, z is the charge on the complex and py=pyridine) have been chemically and electrochemically synthesised via reduction-induced substitution reactions from [ReCl₆]^2-. These complexes have been characterised using electrochemical and spectroelectrochemical techniques. Seven members of the series, namely, [ReCl₅py]^1-, trans-, cis- [ReCl₄(py)₂]^0,-1, mer-[ReCl₃(py)₃], trans[ReCl₂(py)₄]¹⁺, [ReCl(py)₅]²⁺ and [Re(py)₆]²⁺, have been structurally characterised by single crystal X-ray diffraction studies. Extended Hückel Molecular Orbital calculations have been performed on the complexes to elucidate which orientation of the pyridine ring(s) gives rise to the most stable structure. The theoretically and experimentally determined structures agree well. The complexes exhibit a wide range of redox processes spanning from Re^II/I to Re^V/IV based couples. The electrochemical data obtained from these complexes have been used to fit two ligand additivity models, those of Bursten and Lever. Practically, Lever's model is more convenient to use than Bursten's model while the latter is more successful in correcting for isomer effects. The linear relationship between the half-wave potentials for the redox couples of the series and either stoichiommetry, n, or the sum of Lever's ligand parameters ΣE_L indicates that the six ligands around the metal centre individually influence the electronic character of the metal centre. Comparison of the UV/Vis/NIR spectra of [ReCl_6-n(py)_n]^z complexes, varying n and z, has resulted in detailed assignments of the charge transfer bands to electronic transitions, including the elucidation of d–d transitions within the non-degenerate t_2g orbitals. To explore how a ligand alters the stability and reactivity of a complex and hence probe the influence of ligand substitution on the electronic structure of the metal centre in the complex, three monosubstituted chlororhenium complexes, [ReCl₅L]^1- (L=benzonitrile, acetonitrile and pyridine), have been electrochemically and spectroelectrochemically studied. The structure of the complex [ReCl₅(NCPh)]^1- has been determined by single crystal X-ray diffraction studies. The three complexes undergo reduction induced substitution reactions which have been fully investigated using several electrochemical techniques.

Sensors play an important role in industry and in academic research for measurement of various chemical and physical parameters in a variety of environments. Optical materials, whose properties (e.g. absorption, colour) change on interaction with a target analyte, are very useful for sensor applications. Among organic optical materials, there is a class showing electrochromic or solvatochromic properties, which have potential to be used as sensor materials. Normally, organic compounds, with electrochromic or solvatochromic properties, have a conjugated system linking donor and acceptor groups in the molecule. During excitation by a field (electric or light), an intramolecular charge transfer takes place resulting in an excited state with different dipole moment to the ground state. A number of such dye compounds have been synthesised in this work, some of them show considerable electrochromism or solvatochromism, such as 3-ethyl-5-{[1-dodecyl-2(lH)-pyridylidene]-ethylidene}-rhodanine. Its absorption maxima are 524 nm in acetonitrile and 584 nm in ether, having a 60 nm shift. It was found that solvatochromism of such compounds was increased with the increase of the chain length of their conjugated system. The conjugated compounds synthesised were deposited onto a transparent substrate either by solution evaporation or by Langmuir-Blodgett film technology. The films formed did respond to some toxic gases such as NO[2], resulting in an absorption wavelength shift in their uv-vis spectra. Pyridinium N-phenoxide betaine dyes are known as good probes for solvent polarity. The best example is ET(30). ET(30) values have been widely used for polarity measurement of solvents. In order to covalently link these betaine dyes to a solid support for convenience of use, a number of dyes with a functional amino group have been synthesised. This amino group forms the basis for linkage. Additionally, modifications were made to the phenoxide end of the molecule to reduce the phenolate pKa. Dichloro and difluoro variations from the parent diphenyl structure were made. Several methods have been used to try to covalently immobilise the betaine dyes synthesised onto a solid support. Some of them have been successfully immobilised onto a silica sorbent by a thiourea linkage or an amide linkage. Immobilised dyes showed reduced but still good solvatochromism. Their ET values demonstrated linear correlation with standard ET(30) values.

A "THEATRE" OF THE COLLECTIVE MEMORY. A "HOUSE" OF THE DEAD. A "MUSEUM" OF THE HISTORY. A "GALLERY" OF FUNERARY ART. AN "OPERA" OF THE FAMILY STORY. A "CARNIVAL" OF THE FUNERAL--THE GRAND FINALE.

Gulf Stream meanders and eddies off the Carolina coast are studied using an ocean numerical model. Numerical simulation results show that the isobathic curvature in the vicinity of the Charleston Bump has great effect on the development and evolution of Gulf Stream meanders and eddies, and the formation of the Charleston Trough, a Gulf Stream meander that appears as a low pressure or depressed water surface region downstream of the bump, is the result of the combined effect of the Charleston Bump and the isobathic curvature in the region. The isobathic curvature plays a major role in enhancing the baroclinic and barotropic energy transfer rates, whereas the bump provided a localized mechanism to maximize the energy transfer rate downstream of the Charleston Bump. The effects of the Gulf Stream meanders and eddies on the cross-shelf transport near the Carolina coast are also studied in the ocean numerical model. There are two factors that affect the ocean circulations on the continental shelf off the North and South Carolina coast: wind and the Gulf Stream meanders and eddies. It is concluded that the combination of the wind effect and the effect of the Gulf Stream meanders and eddies caused the red tide bloom event in the North Carolina near shore waters in October 1987. Neither wind alone nor the Gulf Stream meander/eddy alone is sufficient to transport the passive tracer to the near-shore area.