Bid-Ask Spread Modelling in the South African Bond Market

Pitsillis and Taylor (2014) calculate bid-ask spread estimates of South African government bonds over a single year, using the models of De Jong and Rindi (2009) and Huang and Stoll (1997). This dissertation tests the effectiveness of both models by comparing the modelled equity spread estimates against the actual equity spread estimates. Furthermore, this dissertation investigates the stability of the De Jong and Rindi (2009) and Huang and Stoll (1997) models in the bond market by extending the spread estimate dataset to run annually over 5 years. The final section of this dissertation proposes a new method of estimating the bond spread through the use of a Kalman filter, as it can be used to leverage information from an onscreen market (albeit a different market) to imply bid-ask spread estimates in an off-screen market. The results indicate that the Huang and Stoll (1997) model consistently outperforms the De Jong and Rindi (2009) model. Furthermore, the yield estimate results of Pitsillis and Taylor (2014) align with the results obtained in this dissertation. The spread estimate results are stable over the 5-year period, indicating a strong provision of liquidity by the Primary Dealers

Contextualizing Gay‐Straight Alliances: Student, Advisor and Structural Factors Related to Positive Youth Development among Members

Gay-straight alliances (GSAs) may promote resilience. Yet, what GSA components predict well-being? Among 146 youth and advisors in 13 GSAs (58% lesbian, gay, bisexual, or questioning; 64% White; 38% received free/reduced-cost lunch), student (demographics, victimization, attendance frequency, leadership, support, control), advisor (years served, training, control), and contextual factors (overall support or advocacy, outside support for the GSA) that predicted purpose, mastery, and self-esteem were tested. In multilevel models, GSA support predicted all outcomes. Racial/ethnic minority youth reported greater well-being, yet lower support. Youth in GSAs whose advisors served longer and perceived more control and were in more supportive school contexts reported healthier outcomes. GSA advocacy also predicted purpose. Ethnographic notes elucidated complex associations and variability as to how GSAs operated

Identifying the Plessy Remainder: State Exploitation of Private Discriminatory-Impact Actions

Public education in the U.S. is arguably more racially segregated now than it was in 1954, when the U.S. Supreme Court declared in Brown v. Board of Education that in the field of public education the doctrine of separate but equal\u27 has no place. Although scholars may differ in the extent they believe that racial integration might be necessary for educational equality, most agree that educational segregation, whether imposed by law, socioeconomics, or happenstance, is not likely to reverse in any meaningful way in the near future. In the absence of a recognized federal right to education, federal-court- supervised school desegregation has been, perhaps, the most viable vehicle for students of color to access educational opportunities enjoyed by white students. This phenomenon remains salient, almost to the point of truism, but not because of any inherent or behavioral differences among students by race or because of any benefits proximity to whiteness affords students of color. Rather, the desegregation remedy is primarily a function of intractable political and socioeconomic realities that enable educational opportunity hoarding by wealthier and whiter stakeholders at the expense of poorer Black stakeholders and stakeholders of color

The Public Right to Education

Public education is the most important function of state and local government and yet not a fundamental right or liberty. This Article engages one of constitutional law\u27s most intractable problems by introducing the public right to education as a doctrinal pathway to a constitutional right to education process in three steps. First, it identifies that the otherwise right-to-education foreclosing case, San Antonio Independent School District v. Rodriguez, only contemplated education as a fundamental right or liberty interest. Second, by identifying public education as a due process protected property interest, this Article presents a viable pathway for circumventing Rodriguez. Third, mindful of myriad judicial competency concerns and consistent with the Court\u27s recent call to reimagine a twenty-first century due process, it reintroduces the public right to understand how school children might appeal to substantive due process to protect their rights to state-created interests. This ambitious yet modest approach covers securing schoolchildren\u27s rights to both discrete education tangibles and the integral educational opportunity that the states have assumed the affirmative duty to provide. This approach also has promise for improving individual rights to quality public schooling

Creating the Urban Educational Desert through School Closures and Dignity Taking

Closures of urban open-enrollment neighborhood schools that primarily serve students of color are intensely controversial. Districts seeking to economize often justify closures by pointing to population shifts in historically densely populated urban areas. They argue that net reductions in a neighborhood’s school-aged population result in underutilized schools, which do a disservice to students at higher cost to districts. Students and their families and communities counter, pointing to histories of district neglect of their schools and recent school expansions in more affluent neighborhoods of similar population density as belying district claims of utility-based downsizing. In this article, I use a critical discourse analysis (CDA) of Chicago Public Schools’ (CPS) school closure hearings process for William H. King Elementary School to show how affected communities experience formal process-driven school closure as an “abnormal justice” moment, characterized by “misrecognizing” community-based notions of property, “misrepresenting” these interests in how they characterize the school’s value, and “maldistributing” the physical school property through closure. I argue that closing schools in this manner compounds the physical property loss with a “dignity taking” that leaves an “educational desert” in its aftermath, with implications for laws on educational property interests

The Perils of Asian-American Erasure

Affirmative action, particularly its most well-known variant, race-conscious college admissions practices, has long occupied a precarious position in constitutional jurisprudence of equal protection and statutory antidiscrimination law. As a policy matter, affirmative action practices are necessary to reduce the impact of durable structural barriers to opportunity that have been imposed on members of identifiable racial groups because of their race. Legally, they’re on far less secure footing. As a constitutional matter, these measures have been summarily divorced from any reparative purpose since the “diversity rationale” emerged from Regents of the University of California v. Bakke as the only compelling interest a public college or university may have in race-consciousness enrollment management. Without “a [predicate] judicial determination of constitutional violation,” a public college or university simply cannot appeal to remedy to justify its use of race classifications. The question currently before the Court in Students for Fair Admissions, Inc. v. University of North Carolina is whether the diversity rationale alone is constitutionally sufficient. In the companion case, Students for Fair Admissions, Inc. v. President & Fellows of Harvard College, the question is whether a federal-funds-receiving educational institution’s consideration of race can be compatible with the Title VI statutory requirement that such institutions not discriminate on racial grounds. Unlike in the University of North Carolina case, the certified question in the President & Fellows of Harvard College case specifically asks if institutional consideration of race “penalize[es] Asian-American applicants.” This is the first time that the Court has explicitly asked for consideration of the effects race-conscious admissions policies might have on Asian Americans. Though this motivating premise is left unstated, in Professor Vinay Harpalani’s article, Asian Americans, Racial Stereotypes, and Elite Admissions, it’s long overdue

THE FABRICATION AND STUDY OF METAL CHELATING STATIONARY PHASES FOR THE HIGH PERFORMANCE SEPARATION OF METAL IONS

The preparation and characterisation of chelating sorbents suitable for the high efficiency separation of trace metals in complex samples, using a single column and isocratic elution, is described. Hydrophobic, neutral polystyrene divinylbenzene resins were either impregnated with chelating dyes or dynamically modified with heterocyclic organic acids, using physical adsorption and chemisorption processes respectively. A hydrophilic silica substrate was covalently bonded with a chelating aminomethylphosphonic acid group, to assess the chelating potential of this molecule. These substrates were characterised in terms of metal retention capability (selectivity coefficients and capacity factors), separation performance, column efficiency and suitability for analytical applications. Chelating molecules with different ligand groups were found to have unique selectivity patterns dependant upon the conditional stability constants of the chelate. Other factors, including mobile phase constituents - complexing agents, ionic strength and pH, column length and column capacity were additionally investigated to examine their effect upon the separation profiles achieved. The promising metal separation abilities illustrated by a number of these chelating columns were exploited for the determination of trace toxic metals in complex sample matrices using High Performance Chelation Ion Chromatography (HPCIC). This included the determination of beryllium in a certified stream sediment, uranium in seawater and a certified stream sediment, and cadmium, lead and copper in a certified rice flour. The results for each analysis fell within the certified limits, and reproducibility was good. The optimisation of post column detection systems using chromogenic ligands additionally gave good detection limits for the metals in each separation system

Development and Pilot of a Patient Reported Outcome Measure for Proximal Thoracic Aortic Aneurysms

Background: Disease specific questionnaires are increasingly being used to evaluate treatment outcomes from the perspective of patients. There are currently no validated questionnaires that measure patient reported outcomes after proximal thoracic aortic aneurysm surgery. Objectives: To develop and pilot a newly formulated patient focussed questionnaire that measures the patient’s health status and health related quality of life before and after proximal thoracic aortic aneurysm surgery. Methods: Based on a literature review, a thematic analysis of audio recorded patient interviews and expert clinical testimony, a pool of items was generated to form a new questionnaire instrument. Suitable patients who were scheduled for elective aortic surgery at Liverpool Heart and Chest Hospital were identified and invited to participate in the pilot study. Patients were asked to complete the questionnaire prior to surgery and then at 6 weeks and 3 months after their operation. The newly developed instrument underwent preliminary testing for its appropriateness, acceptability, feasibility, interpretability, precision, reliability and responsiveness. Results: Several items from the CROQ (Coronary Revascularisation Outcomes Questionnaire) formed the basis of the instrument, with the addition of 10 items derived from a newly formulated conceptual model of proximal thoracic aortic disease. The items were arranged into four domains (symptoms, physical, psychosocial and cognitive). Initial testing showed that the newly developed instrument performed to acceptable standards. It showed good internal consistency (Cronbach’s alpha results for all domains >0.85), and test retest reliability (intraclass correlation coefficient for all domains >0.85). In paired sample tests, the values in each domain led to statistically significant differences from baseline at either 6 weeks or 3 months (p<0.05), supporting the construct validity and responsiveness of the instrument. Conclusions: The new instrument demonstrated satisfactory validity as well as good internal reliability and test retest reliability for each item across all four domains. The initial findings suggest that the measure is sensitive and responsive to the effects of surgical treatment for proximal thoracic aortic aneurysms

Compliant rolling-contact architected materials for shape reconfigurability.

Architected materials can achieve impressive shape-changing capabilities according to how their microarchitecture is engineered. Here we introduce an approach for dramatically advancing such capabilities by utilizing wrapped flexure straps to guide the rolling motions of tightly packed micro-cams that constitute the material's microarchitecture. This approach enables high shape-morphing versatility and extreme ranges of deformation without accruing appreciable increases in strain energy or internal stress. Two-dimensional and three-dimensional macroscale prototypes are demonstrated, and the analytical theory necessary to design the proposed materials is provided and packaged as a software tool. An approach that combines two-photon stereolithography and scanning holographic optical tweezers is demonstrated to enable the fabrication of the proposed materials at their intended microscale