Previous studies completed with humans have revealed insight into the effects of anxiety on attention tasks such the dot-probe task, but there is little information about such effects on non-human primates. This study aimed to assess whether anxiety or anxious behaviors would impact rhesus macaque performance on a three stimuli paradigm similar to the dot-probe task. Utilizing images of conspecifics (strong threat, mild threat, and neutral), eight monkeys were video recorded completing a task that required them to slide two doors, which held these images, to the side to obtain a treat. We hypothesized that behavioral phenotype (high or low anxiety) would affect attention on this modified dot-probe task. Additionally, we predicted that time spent looking at mildly threatening stimuli would be positively correlated with high levels of anxious behaviors (e.g., scratching, yawning, pacing, self-biting) and cortisol concentrations over a four month period. We also predicted that a higher percentage of the mildly threating stimuli as a first choice would be positively correlated with high levels of anxious behaviors and cortisol concentrations. However, anxious behaviors and cortisol concentrations did not affect performance on this task. Interestingly, a sex difference was found for the mild threat stimuli, with females taking significantly more time to complete the task when presented with the mild stimuli (p = 0.01), and also looking at the mild stimuli longer than males (p = 0.03). These data suggest that males and females interpret ambiguous facial expressions differently, possibly indicating the significance of attention in female dominance hierarchies in macaque social groups.

In this thesis, the single-level correlated quantum dot attached to two BCS superconducting leads is analyzed. A difference in the superconducting phases of the leads induces the DC Josephson supercurrent in the junction. In this setup, the influence of asymmetrical dot-lead couplings on transport properties is clarified analytically. The coupling asymmetry and the phase difference can be combined into one function, which allows us to calculate physical properties of a system with coupling asymmetry from the properties of its effective symmetric counterpart. The coupling asymmetry turns out to be an important parameter which influences the position of the 0 − �෰ quantum phase transition even in the strongly correlated Kondo regime. Further, this thesis contributes to the interpretation of an AC Josephson current measurement, in which a surprising drop in the amplitude was observed in the Kondo regime. The experimental setup is characterized using numerical renormalization group calculations of the equilibrium many-body spectra. Possible quantum-point-contact- based interpretations are discussed. Although a drop in the AC Josephson current at the experimental bias voltage is also expected in a quantum point contact, we conclude that the physical mechanisms causing it in the quantum dot system are likely not...

This thesis is devoted to design and build a comprehensive business plan with a view to future implementation in practice. The work is devoted to complete the process from setting up a company to develop a business plan and its planned implementation. The introductory part describes the theoretical foundations for new business, which are followed by my knowledge in analytical and practical part. The practical part is focused on developing very specific dot-com business plan, there is an emphasis on feasibility in practice.

Les nouvelles exigences du diagnostic clinique et de la thérapeutique, particulièrement en termes d’examens au chevet du patient et en médecine de précision, ont conduit à une demande croissante d’analyses à la fois multiplexées et présentant un rendement important, et ce d’un grand nombre de biomolécules au sein d’un échantillon unique. La thèse se concentre sur le développement de biosenseurs multiplexés basés sur le transfert d’énergie par résonance de type Förster résolu en temps de complexes de lanthanide vers des colorants organiques ou des boîtes quantiques. Je présente plusieurs techniques novatrices permettant la détection simultanée et multiplexée de protéines biomarqueurs du cancer (récepteur du facteur de croissance épidermique) ou de microARNs (hsa-miR-20a-5p, hsa-miR-20b-5p et hsa-miR-21-5p) avec de très faibles limites de détection. J’ai utilisé différentes stratégies afin d’obtenir des détections multiplexées telles la détection multiplexée spectrale basée sur les différents spectres d’émission de différents luminophores, et la détection multiplexée temporelle basée sur les durées de vie distinctes des états excités des luminophores. Ces travaux ne sont pas seulement une recherche appliquée qui peut être utilisée en diagnostic clinique, mais constituent également une recherche fondamentale sur le FRET résolu en temps qui ouvre de nouvelles perspectives de détection et augmente considérablement le nombre de biomarqueurs pouvant être détectés. / The new mission of clinical diagnostics and therapeutics, especially in point-of-care testing and precision medicine, has led to an increasing demand for multiplex and high throughput analyses of large numbers of biomolecules within a single sample. The thesis focuses on developing multiplexed biosensors based on time-resolved Förster resonance energy transfer from lanthanide complexes to organic dyes or quantum dots. I present several new techniques to simultaneously and multiplexed detect cancer related protein biomarkers (human epidermal growth factor receptor) or microRNAs (hsa- miR-20a-5p, hsa-miR-20b-5p and hsa-miR-21-5p) with very low limits of detections. I have used different strategies to achieve multiplexed detections such as spectral multiplexed detection based on different emission spectra of different luminophores, and temporal multiplexed detection based on distinguishable excited-state lifetimes of luminophores. The work is not only an applied research that can be used in clinical diagnostics but also a fundamental research of time-resolved FRET, which opens a new dimension of detection and greatly increases the number of biomarkers that can be detected.

Thesis (MSc (Radiography))--Cape Peninsula University of Technology, 2019 / Introduction: After-hours diagnostic imaging is essential in the majority of large public hospitals, as it plays a vital role in the treatment and management of patients. Radiologists are not always available after hours to provide reports on radiographic images since, nationally and globally, there is a shortage of these professionals. Radiographic images are frequently interpreted by emergency physicians after hours. Thus, while diagnostic imaging represents an essential component in patient care (including management and treatment), according to the literature, a significant cause of clinical error occurs through the misinterpretation of radiographic images by emergency physicians. The aim of this study was to determine emergency physicians’ views on whether there was a need for an after-hours diagnostic radiology reporting service in emergency departments at some public hospitals, in the Durban Metropole. It is important to note that in addition to the above, this study calculated the number of radiographic examinations performed after-hours, and the number that was reported by the radiologist during office hours, since there was no radiology cover after hours. Methods: A descriptive cross-sectional quantitative survey design was employed using a self-administered questionnaire as a data collection instrument completed by emergency physicians at four public hospitals. In addition, additional data was collected to determine the number of radiographic examinations that had been performed after hours, at the selected four public hospitals over a period of three months, as well as the number of radiographic examinations that was reported on. This enabled the authors to determine the number of radiographic examinations that went unreported during this study period. Results: A total of 39 emergency physicians participated in the survey, with a mean and median age of 39.46 and 38 years, respectively (SD = 9.11 years). The results of this study showed that between 0.1% and 0.6% of radiographic examinations performed after hours were reported on by radiologists during office hours, for this study period. This implies that less than 1% of all examinations produced after hours at the four public hospitals, received a radiology report. Emergency physicians felt that the interpretation of images took up valuable time. The survey found that there was near total consensus amongst respondents on whether they prefer after-hours reporting to be performed by a radiologist as 46.2% (n = 18) of the respondents strongly agreed and 41.0% agreed (n = 16). Furthermore, a total of 35.9% (n=14) of respondents agreed and 43.6% (n=17) strongly agreed, that having a reporting radiographer reporting on radiographic images after-hours, would benefit patient flow. The survey also found that 92% of the sampled emergency physicians agreed (59.0% strongly agreed and 33.3% agreed, respectively) that there was a need for further training in the interpretation of radiographic images. Discussion: From the above results, it is evident that since the majority of radiographic examinations went unreported after hours, the task to interpret the radiographic images is left to the emergency physicians as part of their patient management. Conceivably, this added image interpretation results in a further increase in the workload of emergency physicians. It is therefore not surprising that emergency physicians preferred that after-hours reporting of radiographic images be done by radiologists. According to the literature, reporting radiographers also play a role in alleviating the workload of emergency physicians and improving patient flow, by providing a report for the radiographic images during after-hours. Thus, reporting radiographers afford emergency physicians additional time to concentrate on patient treatment, resulting in faster patient throughput. Reporting on radiographic images is not yet included in the scope of the South African radiographer. The findings of this study, though, suggested that there was a need for emergency physicians to undergo training in the interpretation of radiographic images. Conclusion: The study recommends that an after-hours reporting service be considered for the four public hospitals concerned. It is recommended that the heads of the emergency and radiology departments further consider offering courses on radiographic image interpretation for emergency physicians.

In der vorliegenden Arbeit wurden neue Materialien für die additive Fertigung für opti-sche Anwendungen entwickelt. Hierbei wurde zunächst ein ORMOCER® Harz für den LCD/DLP 3D-Druck synthetisiert und charakterisiert. Das Material zeigte eine gute Druckbarkeit, gute optische Eigenschaften und eine hohe Stabilität gegenüber Belas-tungen mit UV-Licht, Temperatur und Luftfeuchtigkeit. Die prozessbedingte Stufenbil-dung für gekrümmte Oberflächen beim LDC/DLP Druck erforderte eine Weiterentwick-lung zu einem Harz, das auch mittels Inkjet-Verfahren gedruckt werden kann. Hierfür mussten die Viskosität des ORMOCER®s und die Einflüsse darauf untersucht werden. Zu diesem Zweck wurde die Synthese entsprechend verändert und die Produkte cha-rakterisiert. Variationen des Wasseranteils, des Katalysators, der Reaktionszeit, der Re-aktionsführung und der Edukte wurden durchgeführt. Harze mit resultierender niedriger Viskosität dürfen zusammenfassend nur zweifach anorganisch vernetzende Edukte mit niedrigem Reibungskoeffizienten beinhalten. Ein H2O-Verhältnis von 0,5 zu den vorlie-genden Si-O-Gruppen resultiert in akzeptablen Viskositäten und einer ausreichenden Stabilität. Als zuverlässiger Katalysator stellte sich HCl heraus. Die Reaktionszeit muss so gewählt werden, dass die Sol-Gel-Synthese abgeschlossen ist. Kürzere Zeiten füh-ren zwar zu kleineren Viskositäten, jedoch auch zu eventuell schlechter Langzeitstabili-tät. Veränderungen in der Reaktionsführung, durch Zutropfen der Edukte, resultierten jedoch vorwiegend zur Erhöhung der Viskositäten. Mit diesen Erkenntnissen wurde an-schließend ein Harz synthetisiert, das erfolgreich ohne weitere Verdünnungsschritte am Inkjet-Drucker prozessiert werden konnte. Dieses Harz ist zusätzlich auch am LCD/DLP Drucker einsetzbar. Als ergänzender Schritt konnte im Anschluss noch gezeigt werden, dass Partikel in Harze zusätzliche Eigenschaften, wie Fluoreszenz, einbringen können. / In the present work, new materials for additive manufacturing for optical applications were developed. First, an ORMOCER® resin for LCD/DLP 3D printing was synthe-sized and characterized. The material showed good printability, good optical proper-ties and high stability against exposure to UV light, temperature and humidity. The process-related step formation for curved surfaces in LDC/DLP printing required fur-ther development of a resin that can also be printed by inkjet. For this purpose, the variables of the viscosity of ORMOCER®s had to be investigated. For this purpose, the synthesis was modified accordingly, and the products were characterized. Varia-tions of the water content, the catalyst, the reaction time, the way of the reaction and the reactants were carried out. In summary, resins with resulting low viscosity may contain only twofold inorganic crosslinking reactants with low friction coefficient. An H2O ratio of 0.5 to the Si-O groups present results in acceptable viscosities and suffi-cient stability. HCl turned out to be a reliable catalyst. The reaction time must be as long as the sol-gel synthesis needs to be completed. Shorter times lead to lower vis-cosities, but also to possibly poor long-term stability. However, changes in the reaction control, for example by adding reactants dropwise, resulted mainly in an increase in viscosity. These findings were then used to synthesize a resin that could be success-fully processed on the inkjet printer without further dilution steps. This resin can also be used on the LCD/DLP printer. As a complementary step, it was subsequently shown that particles can introduce additional properties, such as fluorescence, into resins. Here, quantum dots, black dyes and refractive index-increasing zirconium dioxide particles were successfully incorporated into LCD/DLP resins and characterized.

In this work an image processing software was developed to extract single nanocrystals luminescence spectra from spectral images containing various noises and parasitic signals. This software helps users to process and analyze experimental data in a simplified and intuitive way and allows quick analysis of large volumes of data. The output results are the distributions of peak emission energy and inter-peak spacing. The software also generates text-files containing the extracted information for further analysis. Also experimental photoluminescence measurements have been performed at liquid nitrogen temperature of 77K, on phosphorous doped silicon nanocrystals. The data were analyzed with the developed software and with other data confirm previous results indicating the accuracy of the methodology used in the code. The implementation of this software for data analysis can process information without human bias and hopefully find hidden patterns that previously been lost when analyzing data manually.

Fungal diseases, Pythium ultimum (Pythium leak) and Helminthosporium solani (silver scurf) have detrimental effects on potato tuber (Solanum tuberosum) quality and yield. Tubers are the world’s fourth largest agricultural food crop and are crucial for feeding a growing population. Bacteria from the genus Streptomyces are known for producing a wide variety of secondary metabolites with antifungal properties. Isolates of Streptomyces have recently shown inhibitory effects towards P. ultimum and H. solani in Petri dish assays. These data suggest that Streptomyces may work as a biocontrol to protect tubers from P. ultimum and H. solani. We tested talc-based powder formulas for their ability to maintain viable Streptomyces spores in storage. The formula that maintained spores the longest was then used to coat varying Streptomyces isolates onto a tuber surface that contained, or would be exposed to P. ultimum or H. solani. Tests were conducted in a lab, greenhouse, and field setting. We found a powder formula that kept 50% of the added Streptomyces spores viable for a period of three to six months depending on the isolate. Isolates with inhibitory effects towards H. solani were applied as a powder on seed tubers infected with H. solani and grown in a greenhouse. Upon completion of the experiment, we found that progeny tubers from neither the treatment nor the control groups contained H. solani. Instead, we found a similar surface pathogen, Colletotrichum coccodes (Black dot), on many of the progeny tubers. While not the target pathogen of this study, some isolates significantly limited C. coccodes compared to the control. This experiment was repeated in a field setting where C. coccodes was again the primary disease found on the progeny tubers. In the field, isolates showed no inhibitory effect towards C. coccodes. Isolates with inhibitory effects towards P. ultimum were applied as a powder onto wounded tubers. One hour later the tubers were exposed to P. ultimum. Isolates did not limit P. ultimum compared to the control after a week of incubation. A follow up experiment revealed that the Streptomyces isolate used needed at least 24 hours of growth to produce antifungal secondary metabolites. Our data suggest that Streptomyces bacteria can easily be stored in a powder and that there are beneficial effects as a biocontrol against C. coccodes. Our data also suggest that timing Streptomyces application for maximum secondary metabolite production may improve its efficacy as a biocontrol.

An alternative molecular recognition approach was developed for sensing small molecule analytes using the differential binding of an allosteric transcription factor (TF, specifically TetR) to its cognate DNA as the molecular recognition element coupled with Förster resonance energy transfer (FRET) to yield an internally calibrated optical signal transduction mechanism. Sensors were evaluated comprising Cy5-modified DNA (FRET acceptor) with either a tdTomato-TetR fusion protein (FP-TF) or quantum dot-TetR conjugate (QD-TF) as the FRET donor by measuring the ratio of acceptor and donor fluorescence intensities (FA/FD) with titrations of a derivative of the antibiotic tetracycline, anhydrous tetracycline (aTc). A proof-of-concept FRET-based biosensor was successfully demonstrated through the modulation of FA/FD signal intensities based on varying analyte concentrations. Sensor design parameters affecting overall signal-to-noise ratio and sensitivity of the sensors are also identified. / 2020-06-03T00:00:00Z

付記する学位プログラム名: 霊長類学・ワイルドライフサイエンス・リーディング大学院 / 京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第22034号 / 理博第4538号 / 新制||理||1652(附属図書館) / 京都大学大学院理学研究科生物科学専攻 / (主査)教授 友永 雅己, 准教授 宮地 重弘, 教授 濱田 穣 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM