The purpose of this study was to determine what effect changes in the item order had on classical and on latent trait test statistics. As well, comparisons were made between students who were allowed to answer the questions in any order, and students who were required to answer the questions In the order presented in the test booklet. The results were then analyzed using the student's ability level as an additional independent factor. Four different formats of a forty item mathematics test were used with 590 students in grade eight. Half of the booklets had the items sequenced from easiest to hardest. The other booklets were sequenced from hardest to easiest. In addition, half of the tests of each sequence had special directions which prevented students from altering the given item difficulty sequence. The classroom teachers provided a rating of each student's ability in mathematics. The order of the items was found to have a significant effect. Tests which were sequenced from hard to easy had a lower mean score. Although students with test booklets with restrictive directions had lower scores on average, it was not a statistically significant difference. There were no significant interactions found. Classical and latent trait item difficulty statistics showed a high degree of correlation. It was concluded that under certain circumstances, the order of the items could effect both classical and latent trait statistics. It was also recommended that care should be taken when assumptions are made about parallel forms or local independence. / Education, Faculty of / Educational and Counselling Psychology, and Special Education (ECPS), Department of / Graduate

The optoelectronics industry continues to demand improved materials, devices and systems for the generation, transmission, detection, amplification and processing of optical signals. Heterojunction phototransistors (HPTs), in recent years, have attracted considerable interest for optical detection due to their intrinsic gain, low noise performance, high-frequency operation and process and the device layer compatibility with heterojunction bipolar transistors for high-speed optoelectronic monolithic microwave/millimetre-wave integrated circuit (OEMMIC) photoreceivers. A key performance parameter of HPTs is their spectral response (SR) which is critical in their usage in optical applications. The SR depends on several inherent factors including material absorption coefficient, refractive index, device structure, doping and temperature of operation along with the external factors such as bias voltage and the energy of incident radiation. The spectral response and optical characteristics of GaAs-based and InP-based sHPTs have been successfully predicted for the first time through an advanced absorption theoretical model. The model is based on the accurate prediction of photocarriers in the active layers of the phototransistor which, when related to the base current of the transistor in forward active mode, enables the prediction of optical characteristics. The importance of collection efficiency in accurate SR modelling is highlighted and the layer dependence of the optical flux absorption profile at near-band gap wavelengths is also investigated and its generalisation as a single-exponential has been refuted for GaAs-based HPTs. Analytical modelling of the spectral response has also been developed from the resolution of continuity equations that govern the excess optically generated minority carrier variation in the active layers of the HPT, taking into account the related physical parameters. Realistic boundary conditions have been considered for efficient device operation and a detailed optical flux absorption profile is constructed for accurate device modelling. This analytical model provides insight into the direct influence of various parameters (such as base width and carrier concentration) on the device performance, thus, providing a valuable optimization tool for the future design of HPTs in optical receivers. The measured results at 635 nm, 780 nm 808 nm and 850 nm for AlGaAs/GaAs HPTs and 980 nm, 1310 nm and 1550 nm for InP/InGaAs HPTs show good agreement with the predicted data, validating the proposed theoretical model. Finally, a detailed absorption model and photoresponse of double heterojunction phototransistors in a top/surface-illuminated orientation has been analyzed with a modified small-signal model. The effect of incident optical illumination on intrinsic small-signal parameters such as resistances and capacitances has been discussed and analyzed for photoresponse modelling.

Ferredoxin (Fd), a fifty-five amino acid electron transport protein of the anaerobe Clostridium pasteurianum, has been chosen as the ideal probe for immunoregulation studies. Its critical feature is that it contains two antigenic determinants satisfying the hypothetical minimum requirement for immunogenicity. It was found that both the antibody (as measured by ELISA) and the lympho-proliferative responses to Fd are linked exclusively to the MHC of mice, mapping to K/I-A. Analysis of the response was undertaken at the determinant level with selective enzyme cleavage products of trypsin and carboxypeptidase A which yield respectively a 52 residue C-determinant peptide (devoid of a functional N-determinant), "C", and a 53 residue N-determinant peptide (devoid of a functional C-determinant peptide), "N",. Through the use of these two molecules ("N" and "C") and a doubly digested molecule, "M", the immune response to Fd was dissected. At first, anti-Fd antibody from high responder, H-2[sup=k], mice was shown to be 10-20% "N" specific with the balance of the response "C" directed, while intermediate responder haplotypes, H-2[sup=b] and H-2[sup=s]. demonstrate equal specificity for the two determinants. H-2 mice were uniformly non-responsive. Fd immune T-cells demonstrated lymphoproliferative capacity mirroring the antibody response of B10.BR (H-2[sup=k]) mice: "C" induced proliferation comparable to that with the native molecule, "N" inducing a much lower response, one matched by the "M" peptide. Next, the "N", "C" and "M" molecules were assessed for their immunogenicity in B10.BR, C57BL/10 (H-2[sup=b])and B10.D2 (H-2[sup=d]) mice. "N" was found to induce limited, if any, antibody production whereas it primes for a very good proliferative response (B10.BR only). "M" induced no antibody response in any strain, and minimal proliferation in B10.BR. "C" induced at least two-fold higher antibody in B10.BR and C57BL/10 as compared to native Fd, and converted the B10.D2 non-responders into responders. "C" induced a weak proliferative response in B10.BR. The data suggest that two determinants exist at the B-cell level, while three determinants account for the T-cell response. / Science, Faculty of / Microbiology and Immunology, Department of / Graduate

When old/new recognition memory is tested with equal numbers of studied and non-studied items and no rewards or instructions that favour one response over the other, there is no obvious reason for response bias. In line with this, Canadian undergraduates have shown, on average, a neutral response bias when we tested them on recognition of common English words. By contrast, most subjects we have tested on recognition of richly detailed images have shown a conservative bias: they more often erred by missing a studied image than by judging a non-studied image as studied. Here, in an effort to better understand these materials-based bias effects (MBBEs), we examined changes in hit and false alarm (FA) rates (and in sensitivity and bias) from the first to fourth quartile of a recognition memory test in eight experiments in which undergraduates studied words and/or images of paintings. Response bias for images tended to increase across quartiles, whereas bias for words showed no consistent pattern across quartiles. This pattern could be described as an increase in the MBBE over the course of the test, but the underlying patterns for hits and FAs are not easily reconciled with this interpretation. Hit rates decreased over the course of the test for both materials types, with that decline tending to be steeper for images than words. For words, FA rates tended to increase across quartiles, whereas for paintings FA rates did not increase across quartiles. We discuss implications of these findings for theoretical accounts of the MBBE. / Graduate

Online equity-based crowdfunding, also known as regulation crowdfunding, or Reg CF, is a financing process by which a large number of individuals pool resources towards the support of a project in return for a pro-rated stake or return. Still in its infancy, crowdfunding has been largely unexplored and minimally tested within the architecture realm, likely due to the high capital requirements and complex building regulations. Yet, as it expands into a viable market, equity crowdfunding may offer architects an alternative: a more democratic, open-source and participatory building process, and the ability to re-position their role as facilitators of catalytic projects. While donation and reward-based crowdfunding platforms (such as Kickstarter and Indiegogo) are used to fund smaller-scale projects, equity-based crowdfunding platforms (such as WeFunder, Small Change and SeedInvest) have been increasingly used in larger-scale real estate transactions. Currently less than 1% of all crowdfunded projects are civic design-focused. A recent study found only 3% of architecture campaigns use equity crowdfunding compared to 71% of reward-based crowdfunding and 14% of donation-based crowdfunding. Equity crowdfunding has raised the highest amount of funds per architecture campaign per crowdfunding type, upwards of $50,000 on average, and the broader US market projects exponential growth, upwards of $8 billion by 2020. Because investors are given equity incentives, they are more likely to contribute higher amounts, provided that there is a strong team and clear business plan. Architects can now test and receive feedback on public sentiment around once-unconventional ideas, and move forward on projects that might not have appealed to conventional investors. Additionally, architects can circulate their proposals with an international group of like-minded possibly-interested investors and support networks; build awareness around challenges they seek to address; showcase their expertise around project types; and improve the likelihood - through increased political and financial capital - that their ideas evolve into reality. This thesis overviews the landscape of crowdfunding in architecture, specifically equity crowdfunding; details how it might be integrated and initiated as an early-stage participatory tool by architects to generate support for their proposals; and explores the implications crowdfunding may have on the architecture process. The thesis tests such a process through a theoretical equity crowdfunding campaign - “Gowanus Crossing” in Brooklyn, NY, which proposes a 290-footlong water remediation bridge across the toxic waterways of the Gowanus Canal. The aggregated system of the bridge incrementally develops as financing becomes available and the project raises immediate public awareness around efforts to clean the water. Overall, this thesis suggests architects are ideally suited for facilitating crowdfunding campaigns. Equity crowdfunding becomes a financing process that will alter the traditional building process but may also become a tool architects could utilize to pro-actively respond amidst the challenges of climate change, political partisanship, and urban disinvestment. / 0 / SPK / specialcollections@tulane.edu

In the Mediterranean basin, human visceral leishmaniasis caused by the protozoan parasite Leishmania infantum is a zoonotic disease that gives rise to 1,200 to 2,000 new cases annually. The domestic dog constitutes its main reservoir, of which some may suffer from a severe chronic disease, canine leishmaniasis (CanL). The sand fly Phlebotomus perniciosus is considered to be the principle vector. Saliva of bloodfeeding vectors of diseases has been used in the past to assess host exposure to vector bites and to evaluate vector control tools. This Ph.D. focused on saliva of P. perniciosus to identify exposure markers that could be used in the preparation of a new vector exposure tool. The first part of this Ph.D. aimed at validating the use of a recombinant salivary protein of P. perniciosus - rSP03B - in endemic settings of CanL. During a cross-sectional study, no significant differences between the antibody (Ab) response against whole saliva or the rSP03B were observed between different regions across the Mediterranean basin. Furthermore, the rSP03B was shown to resemble the native protein. During a subsequent study this protein was used to assess the seasonal dynamics of the canine Ab response to P. perniciosus in an endemic area of L. infantum. This study elucidated that also in a heterogeneous...

Background: Accurate and appropriate spirometry reference values allow for early detection of respiratory illness and perform an important role in monitoring lung health. There is, in general, a scarcity of data from Africa, and the Global Lung Initiative (GLI) has published global reference equations but models did not include data from African studies. The aim of this study was to investigate lung function in a group of healthy South African females and the applicability of the GLI reference equations. Methodology: Maternal lung function testing was undertaken at 6 to 10 weeks post-partum as part of a birth cohort study, the Drakenstein Child Health Study. Pre- and post-bronchodilator spirometry was performed according to a standardised protocol and correlated with clinical information. Bronchodilator response was assessed by repeating spirometry 15 minutes after administration of inhaled 400mcg salbutamol. Results: A total of 462 women were included, mean age 17 years (range 18- 42 years). The GLI reference equations fitted the observed lung function results well for the group of mothers who did not self-report smoking or asthma. There were 64 (14%) mothers with an abnormal Forced Expiratory Volume in 1 Second (FEV 1) result, 60 (13%) mothers with an abnormal Forced Vital Capacity (FVC), and 35 (8%) mothers with an abnormal FEV 1 /FVC ratio. There were 22 (5%) mothers who had reversible FEV 1; the rate of undiagnosed reversibility was 4% of the cohort. High body mass index was associated with a higher risk for poor FVC and FEV 1 /FVC lung function, OR 1.40 (CI: 1.01, 1.65) and OR 1.25 (CI 1.10, 1.95) respectively. Mothers with a higher socio-economic status had better FEV 1 with the adjusted SES OR 0.65 (CI 0.36, 1.08). Conclusions: There was a high prevalence of abnormal lung function in this cohort of South African adult females and a number of cases of undiagnosed reversibility. Spirometry testing is important to diagnose lung disease in South African communities. The GLI's reference equations were appropriate and applicable for a cohort of South African adult women.

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