This research investigates the development of digital video filmmaking in West Africa using Ghana and Burkina Faso as case studies within the context of new technologies. The key research questions that guided the study were how do the economic, social and political contexts of video filmmaking affect the development of a digital video film industry in Ghana and Burkina Faso? and how have the perceptions of digital technologies (held by filmmakers and other stakeholders) impacted upon the development of digital video film making in West Africa? Using field interviews with stakeholders in the video film industry in Ghana and Burkina Faso, as well as with the West African diaspora community in the UK, document research, textual references, and personal observation, the research discusses the challenges of new digital and video technologies, and their implications for the development of the video film industry. The research establishes that video and digital technologies are offering many people the opportunity to make films. There is however, a plethora of new digital technologies that enable the work of video film producers, which require closer examination. The research suggests that the impact of the digital revolution has been limited, and a number of factors account for this. The study offers recommendations that might contribute to discussions on finding solutions to the development of a professional, regulatory and practical video filmmaking environment. This would lead to the formulation of policies that impact positively on filmmaking in the region, and consequently increase the capacity of local productions to compete on the international film scene.

Shiga toxin-producing E. coli (STEC) cause diarrhea, hemorrhagic colitis, and hemolytic uremic syndrome (HUS). All STEC produce one or both of two Shiga toxins, Stx1 and Stx2. STEC strains that produce Stx2 are more strongly associated with HUS than strains that produce Stx1 or both Stx1 and Stx2. Epidemiologic evidence indicates a recent increase in the rate of HUS among STEC outbreaks. The increasing rate of HUS could be explained by a shift in the toxin profiles of STEC strains. The purpose of this study was to examine trends in toxin profiles of human STEC O157 isolates from 1996 to 2008 and to assess whether an increase in the number of Stx2-only-producing strains could be correlated with a recent increase in HUS cases. Data from three independent datasets, collected from PulseNet, eFORS and NARMS, were used. Additionally, trends such as seasonal variations, geographical variations, gender differences, and age differences were examined for each toxin profile. Results from this study show a shift in the toxin profile of human STEC O157 strains in the United States, in that the proportion of Stx2-only producing strains has increased dramatically since 1996.

Audio signal processing systems for converting two-channel (stereo) recordings to four or five channels are increasingly relevant. These audio upmixers can be used with conventional stereo sound recordings and reproduced with multichannel home theatre or automotive loudspeaker audio systems to create a more engaging and natural-sounding listening experience. This dissertation discusses existing approaches to audio upmixing for recordings of musical performances and presents specific design criteria for a system to enhance spatial sound quality. A new upmixing system is proposed and evaluated according to these criteria and a theoretical model for its behavior is validated using empirical measurements. / The new system removes short-term correlated components from two electronic audio signals using a pair of adaptive filters, updated according to a frequency domain implementation of the normalized-least-means-square algorithm. The major difference of the new system with all extant audio upmixers is that unsupervised time-alignment of the input signals (typically, by up to +/-10 ms) as a function of frequency (typically, using a 1024-band equalizer) is accomplished due to the non-minimum phase adaptive filter. Two new signals are created from the weighted difference of the inputs, and are then radiated with two loudspeakers behind the listener. According to the consensus in the literature on the effect of interaural correlation on auditory image formation, the self-orthogonalizing properties of the algorithm ensure minimal distortion of the frontal source imagery and natural-sounding, enveloping reverberance (ambiance) imagery. / Performance evaluation of the new upmix system was accomplished in two ways: Firstly, using empirical electroacoustic measurements which validate a theoretical model of the system; and secondly, with formal listening tests which investigated auditory spatial imagery with a graphical mapping tool and a preference experiment. Both electroacoustic and subjective methods investigated system performance with a variety of test stimuli for solo musical performances reproduced using a loudspeaker in an orchestral concert-hall and recorded using different microphone techniques. / The objective and subjective evaluations combined with a comparative study with two commercial systems demonstrate that the proposed system provides a new, computationally practical, high sound quality solution to upmixing.

This research examined the influence of organic loading rate (OLR) and biosolids type on the performance of fermentative H2-producing membrane bioreactors (HPMBRs) with respect to H2 production and membrane fouling. Five OLRs ranging from 4.0 to 30 g COD L-1 d-1 were examined in a lab-scale HPMBR. The system performance with both suspended and granulated biosolids was also investigated. The H2 yield from the suspended biosolids HPMBR was not significantly influenced by OLR at OLRs ≤ 13 g COD L-1 d-1, appeared to be maximized at an OLR of 22 g COD L-1 d-1, and then decreased as the OLR was increased further. An optimum OLR that maximizes H2 yield may be near the OLR that causes reactor overload with respect to substrate utilization. Under the same operating conditions, the H2 yield from a suspended HPMBR was significantly higher than that from a granulated HPMBR. A higher H2 consumption rate and a higher concentration of bound extracellular polymeric substances from the granulated HPMBR may contribute 5–48% and 25–67% of the H2 production difference between the two systems, respectively. The experimental results accompanied with microscopic examination of fouled membrane surfaces indicated that biosolids deposition and colloidal adhesion were the two dominant membrane fouling mechanisms in the HPMBRs. Membrane fouling was characterized by two distinct stages: an initial stage with a relatively higher fouling rate and a second stage with a lower fouling rate. Membrane fouling rates and resistances were influenced by the properties of biosolids and colloids in the mixed liquor. The fouling rates increased with increased biomass concentration, but decreased as colloids became more negatively charged. The irreversible and irremovable fouling resistance increased with increased concentration of colloids, while the removable fouling resistance had no relationship with biomass concentration. Biosolids granulation may benefit membrane performance due to a lower colloidal concentration produced. The single cake filtration model was proper to simulate membrane performance in the initial fouling stage. Both cake filtration and combined cake-standard models provided good fits for the second fouling stage, whereas future study is required to improve model predictability for membrane fouling in this stage.

This research examined the influence of organic loading rate (OLR) and biosolids type on the performance of fermentative H2-producing membrane bioreactors (HPMBRs) with respect to H2 production and membrane fouling. Five OLRs ranging from 4.0 to 30 g COD L-1 d-1 were examined in a lab-scale HPMBR. The system performance with both suspended and granulated biosolids was also investigated. The H2 yield from the suspended biosolids HPMBR was not significantly influenced by OLR at OLRs ≤ 13 g COD L-1 d-1, appeared to be maximized at an OLR of 22 g COD L-1 d-1, and then decreased as the OLR was increased further. An optimum OLR that maximizes H2 yield may be near the OLR that causes reactor overload with respect to substrate utilization. Under the same operating conditions, the H2 yield from a suspended HPMBR was significantly higher than that from a granulated HPMBR. A higher H2 consumption rate and a higher concentration of bound extracellular polymeric substances from the granulated HPMBR may contribute 5–48% and 25–67% of the H2 production difference between the two systems, respectively. The experimental results accompanied with microscopic examination of fouled membrane surfaces indicated that biosolids deposition and colloidal adhesion were the two dominant membrane fouling mechanisms in the HPMBRs. Membrane fouling was characterized by two distinct stages: an initial stage with a relatively higher fouling rate and a second stage with a lower fouling rate. Membrane fouling rates and resistances were influenced by the properties of biosolids and colloids in the mixed liquor. The fouling rates increased with increased biomass concentration, but decreased as colloids became more negatively charged. The irreversible and irremovable fouling resistance increased with increased concentration of colloids, while the removable fouling resistance had no relationship with biomass concentration. Biosolids granulation may benefit membrane performance due to a lower colloidal concentration produced. The single cake filtration model was proper to simulate membrane performance in the initial fouling stage. Both cake filtration and combined cake-standard models provided good fits for the second fouling stage, whereas future study is required to improve model predictability for membrane fouling in this stage.

Thesis (Ph. D.)--University of Oklahoma. / Bibliography: leaves 158-168.

Master of Science / Food Science Institute - Animal Sciences and Industry / Randall K. Phebus / A variety of antimicrobial processes are used to reduce pathogen risks on commercially processed raw beef. Little research has evaluated chlorinated water on beef tissues, especially in a processing water dip scenario. Interest in nanobubble technology has increased due to its proposed surfactant properties, but it is undetermined whether this improves antimicrobial effectiveness of chlorine-based solutions in food applications. Benchtop studies were conducted to evaluate chlorinated nanobubble waters (0 to 11.94 ppm) against Shiga toxin-producing Escherichia coli O26, O45, O103, O111, O121, O145, and O157:H7 (STEC-7), Salmonella spp., and USDA-approved non-pathogenic STEC surrogates 1) in pure culture with the goal of characterizing the lethality contributions of pH (5 or 7), temperature, free available chlorine level (FAC), inclusion of nanobubbles, or a combination thereof; 2) in select chlorinated nanobubble “red water” (water containing 0.1% beef purge) solutions; and 3) on the surface of lean and fat beef tissue. In pure culture solutions, surrogates demonstrated greater resistance (P ≤ 0.05) to chlorinated solutions (3.4-5.5 log CFU/mL reductions) with increased reductions at the higher (11.94 ppm) FAC levels. STEC-7 and Salmonella population reductions were also notably reduced (3.3-7.1 log CFU/mL) by the higher FAC concentrations. No definitive impacts of temperature, nanobubble inclusion, or acidic pH were observed. At an average 5.23 ppm FAC in red water, all microbial populations were reduced by > 6 log CFU/mL after 60 minutes. Reductions of target organisms on inoculated lean and fat tissues were ≤ 1 log CFU/g in red water; likely due to the inability to maintain FAC levels above 0.7 ppm in the presence of organic loading. An in-plant antimicrobial validation study of a proprietary raw beef manufacturing process was conducted to determine the effectiveness of a recirculating acidic nanobubble water system, chlorinated to 5 ppm FAC using EO water generated concentrate, against the USDA-approved STEC surrogates. Preliminarily, inoculated beef trim was introduced into the system targeting 5 ppm FAC; chlorine concentrate reinfusion rates were determined to establish applicable operational parameters and sampling strategies for the system. An optimized in-plant study was conducted. Meat inoculated at ~ 7 log CFU/g was introduced into the recirculating chlorinated nanobubble system every other day over 6 days, achieving an average 1.6 log CFU/g surrogate reduction on inoculated meat throughout the manufacturing process. Approximately 2.7 log CFU/g of residual surrogates were recovered on non-inoculated meat ~35 minutes after inoculated meat entered the system, indicating that harborage of microbial contamination on processing equipment can lead to subsequent contamination carry-over that must be controlled during processing. Surrogate organisms were recovered by enrichment only from non-inoculated meat 24 h after inoculated meat processing on alternate days, likely stemming from inadequately sanitized processing equipment after inoculated batch processing. Control of the residual surrogate population in the system following inoculation was accomplished through daily equipment sanitation and boosting recirculated processing water to 50 ppm during a 4-h sanitation period (no beef entering system). The optimized study will be used as an antimicrobial process validation against STEC and Salmonella spp. in beef manufacturing.

We augment a model of endogenous credit cycles by Matsuyama et al.(2016) with human capital to study the impact of human capital on the stability of central economic aggregates. Thus we offer a linkage between human capital formation and credit market instability on a macrolevel combined with an analysis of functional income distribution. Human capital is modelled as pure external effect of production following a learning-by-producing approach. Agents have access to two different investment projects, which differ substantially in their next generations spillover effects. Some generate pecuniary externalities and technological spillovers through human capital formation whereas others fail to do so and are subject to financial frictions. Due to this endogenous credit cycles occur and a pattern of boom and bust cycles can be observed. We explore the impact of human capital on the stability of the system by numerical simulations which indicate that human capital has an ambiguous effect on the evolution of the output. Depending on the strength of the financial friction and the output share of human capital it either amplifies or mitigates output fluctuations. This analysis shows that human capital is an essential factor for economic stability and sustainable growth as a high human capital share tends to make the system's stability robust against shocks. / Series: Department of Economics Working Paper Series

The increasing number of Extended Spectrum Beta-Lactamase (ESBL) producing Escherichia coli (E. coli) associated with sepsis in China is the reason for designing the current study. During 2014-2016, thirty hospitals representing 10 different provinces in China was involved in collecting E. coli isolates causing blood stream infections. Early treatment with suitable antibiotics have been found to be of lifesaving importance in the case of care for septic patients. Thorough understanding of the pathogens involved is therefore crucial. Using antimicrobial susceptibility testing, PCR and Multi Locus Sequence Typing (MLST), the molecular characteristics of ESBL producing E. coli isolates could be determined. This study can report that the most common ESBL producing genes found were CTX-M-14 (51 isolates, 45,5%), CTX-M-55 (23 isolates, 20,5%) CTX-M-15 (22 isolates, 19,6%). In addition, 2 isolates (1,8%) were found to be SHV-11 positive which is another ESBL producing gene. As a side finding, 5 isolates harbored Metallo-beta-lactamase (MBL) encoding genes such as NDM-5 and NDM-1 which were found to coexist with CTX-M-55 and CTX-M-14 respectively. An MLST analysis resulted in the finding of 25 different and 17 previously unknown (16,2 %) sequence types. The most common sequence types were ST131 (18 isolates, 17,1 %) as reported previously.  No significant differences in antimicrobial susceptibility were identified whether ESBL producing genes such as SHV and CTX-M was present or not. This study indicates that there could be novel resistance mechanisms present among those isolates not encoding the genes of interest. However, this finding requires further research before it can be confirmed.

The diagnostic methods implemented at the Canadian Food Inspection Agency for the detection of Shiga toxin producing E. coli (STEC) are time consuming and tedious, taking up to 5 days before a positive sample can be confirmed. The goal of this project was to streamline the detection procedure for serogroup O157 and 6 important non-O157 serogroups of STEC. Following a short enrichment step (4-6 hrs), two approaches were considered: (1) the filtration of enrichment culture through a gradient of filtration membranes (decreasing pore sizes), followed by capture using specific monoclonal antibody (mAb)-coated Dynabeads, and detection via fluorescence microscopy, (2) the addition of enrichment culture into a flow through system consisting of a column packed with large polystyrene beads (≥ 100 μm) coated with specific mAbs for capture. The results indicate that the filtration approach can only be applied to simpler food matrices. However, at least 100 CFU of the target STEC could be recovered using the filtration system following 4 hrs of enrichment of these matrices spiked with ≤ 15CFU of the target STEC. Similar capture results were obtained in the second approach using specific mAbs immobilized on covalently coupled protein G polystyrene beads and diluted enrichment media. A combination of these strategies together with immunofluorescence microscopy (IMS) and polymerase chain reaction (PCR) could provide diagnostic laboratories with a means to confirm a positive sample within 2 days of testing.