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With the threats facing the world today, there is an ever-increasing need for training the the fields of radiochemistry and nuclear forensics. Training and research in these fields requires reference materials that accurately represent materials that could potentially be encountered. Unfortunately, many of the historical samples of debris from nuclear weapons tests remains classified. Because of this, there is a need for realistic surrogates. This research focuses on the development of surrogates for the bulk and particulate nuclear melt glass that is expected to be found in an urban setting after a nuclear event. A mathematical model for the creation of surrogate melt glass precursor matrices was developed. The model was used to determine the elemental composition of melt glass precursor for the Trinity site, New York City, and Houston, Texas. The precursor matrices were used to generated surrogate bulk nuclear melt glass. While this has been previously done for the Trinity site, this study marks the first time that surrogate bulk nuclear melt glass has been produced for urban scenarios. A thermal spray coater was used to demonstrate that the precursor matrices can be used to generate surrogate particulate melt glass. Both the bulk and particulate surrogate melt glasses were analyzed using scanning electron microscopy (SEM). Chemical differences on the surface of the samples was determined using backscatter electron analysis (BSE). Energy dispersive spectroscopy (EDS) was used to determine the elemental composition of features observed via SEM. A more complete elemental analysis of the surrogates was conducted using inductively coupled plasma time-of-flight mass spectrometry (ICP-TOF-MS). Crystalline structure was determined using powder X-ray diffraction (P-XRD). Expected fission and activation products cause for each of the matrices were modeled. Notional uranium-fueled and plutonium-fueled improvised nuclear devices (IND) were examined in the radiological models. Using the developed mathematical models were in conjunction with the synthesis techniques outline, it is apparent that these methods will be able to provide for and meet the current academic, training, and research needs. However, further optimization of the synthesis and analysis processes is needed before large scale production can occur.

The ability of the central nervous system (CNS) to execute sophisticated functions with remarkable efficiency relies on extensive cross-talk between a number of specialized cell types. Myelination is a quintessential example of such cellular communication in which highly specialized oligodendroglia extend compacted spirals of cell membrane around individual axons of multiple neurons. Functionally similar to the insulation that encases household electrical wiring, myelin accelerates the conduction of electrical signals that underlies complex behavioral outputs such as movement and sensation. A recent approach to better understand the dynamic relationship between axons and oligodendrocytes has been the development of models in which oligodendrocytes can be experimentally eliminated from living tissues. However, confounding factors inherent in each of the existing models complicate data interpretation. Limitations include dubious cell specificity, a mechanism of cell death that is not physiological, and/or the requirement of a stimulated peripheral immune system, a condition often associated with pathology. The current work proposes a novel experimental model that circumvents these issues. The basic premise of the model is that activation of a genetically encoded cell death program that is inherent in most cells can be experimentally controlled and targeted specifically to myelinating oligodendrocytes. In this way, oligodendrocytes can be eliminated from living tissue by a physiological mechanism that by definition does not stimulate an immune response. By analyzing changes in natural phenomena in the absence of oligodendrocytes, if all else is equal, it is possible to begin to understand their roles in complex cellular processes such as developmental myelination and adult myelin regeneration, both of which are critical for nervous system function. In the current studies, oligodendrocytes were depleted in both the adult and developing central nervous systems. At both ages, myelin was degraded by twenty-four hours after oligodendrocyte apoptosis resulting in the recruitment, activation, and partial phagocytosis by resident microglia. Peripheral T-lymphocytes were notably absent until seven days after induced apoptosis. The ensuing proliferation of oligodendrocyte progenitor cells was selective and local, implying an efficient and space-delineated mechanism for cell replacement even in the adult CNS. Depletion of oligodendrocytes during neonatal development resulted in severe myelin deficiency that recovered almost entirely within two weeks. Pilot studies indicate that heavy demands on the plasticity of a developing CNS render it susceptible to myelin challenges later in life. The iCP9 model of inducible oligodendrocyte apoptosis provides information useful to both basic scientists and clinicians. On a basic level, the iCP9 technology provides a tool for studying brain function with only a fraction of the oligodendrocytes and without involving or perturbing the immune system. Given that myelin destruction is hallmark pathology of multiple sclerosis, the current studies also propose novel ideas and new models to explore the underlying biological basis of an enigmatic disease.

There has long been a conflict at the heart of theories of distributive justice between a concern to allow individuals autonomy and avoid paternalism, on the one hand, and a concern to promote individual well-being, on the other. The capability approach attempts to tread this line, by providing individuals with certain central capabilities or opportunities: these preserve a space for individual freedom and choice, yet ensure that all individuals have access to those things that are considered central for a flourishing life. Further, ‘all individuals’ is meant expansively, aiming to accommodate the experiences and needs of many groups that are often ignored. However, the perfectionist roots of the capability approach have led to concerns being raised that it cannot successfully protect autonomy and promote inclusivity, and that it will, instead, justify paternalism. I contend that, in particular, Martha Nussbaum's influential account of capabilities falls prey to just this objection. In my thesis I defend a version of the capability approach that is strictly anti-paternalist, and accommodates a variety of non-standard human experiences. I argue that this focus on autonomy need not be bought at the expense of individual well-being, and that encompassing atypical experiences need not be bought at the expense of accommodating more standard conceptions of the good. I advocate an understanding of capabilities as opportunities to exercise control in certain domains of our life, in contrast to Nussbaum’s construal of capabilities as opportunities to perform (or not) particular valuable functionings. I test my theory against a number of cases that have traditionally provide challenging for anti-paternalists, and theorists of justice more generally – including physical disability, conditions such as asexuality and Asperger’s Syndrome, and voluntary slavery and amputation – to demonstrate that my theory is better able to accommodate such unusual preferences and needs, without paternalism.