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Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterized by the clinical manifestation of attention deficits and/or hyperactivity. The Adhesion G Protein-Coupled Receptor L3 (ADGRL3) gene is strongly linked to ADHD susceptibility, and is homologous to the adgrl3.1 gene in zebrafish. The aim of this thesis was to investigate the behavioural phenotypes of adgrl3.1 knockout zebrafish and associated interactions with environmental factors. We first investigated the behavioural phenotypes of adult adgrl3.1 knockouts focusing on impulsivity, attention, decision making, locomotion, anxiety, memory, and cognition. Here, we found that adgrl3.1 knockouts show increased locomotion, impulsivity, attention deficits, anxiety, abnormal repetitive behaviour, and deficits in cognitive flexibility. We discovered a potentially novel mechanism that may underlie these behaviours, characterized by upregulation of the noradrenergic transporter, together with lower levels of DOPAC/DA in the telencephalon. The behavioural phenotype of adgrl3.1 knockout was reversed by pretreatment with atomoxetine (norepinephrine reuptake inhibitor) supporting our discoveries that norepinephrine has an essential role in the ADHD-like behaviours. The interactions of this gene with environment were also analysed focusing on how environmental enrichment, social isolation and early-life stress can affect ADHD-like behaviour. In conclusion, we showed that adgrl3.1 mutants can be a reliable model to study ADHD and its comorbidities in zebrafish. We have also demonstrated that environment can significantly affect adgrl3.1 altered behaviour positively or negatively, depending on context. Finally, for the first time, here we showed changes in the noradrenergic system that may contribute to the development of new combined treatments and further our understanding of the mechanisms underlying adult ADHD-like behaviour across species.

We give a parametrization of the inertial classes of smooth representations of inner forms of GL(n) over a p-adic field, based on type-theoretic invariants. Then we give a complete description of the behaviour of this parametrization under the Jacquet–Langlands correspondence, proving a conjecture of Broussous, Sécherre and Stevens on preservation of endo-classes. As an application of this result, we construct a Jacquet–Langlands transfer of types and Serre weights for central division algebras, and use it to deduce a form of the Breuil–Mézard conjecture, for discrete series Galois deformation rings and types of central division algebras, from the conjectural statement for GL(n).

This thesis presents an investigation of the dynamics of the ocean circulation off West Antarctica, a region characterised by intense ice shelf loss. The Ross Gyre, located in the western side of West Antarctica, is studied through remote sensing techniques that retrieve information of the sea level from sea ice leads. The seasonality of the gyre is driven by the winds through two distinct modes. The first mode, associated with circumpolar winds, reduces sea level at the end of summer through northward Ekman transport. Regional sea level rises in winter due to ice cover, which reduces the wind stress on the ocean. The second mode, associated with the Amundsen Sea Low (ASL), controls the transport and area of the Ross Gyre and the coastal throughflow with a semi-­‐ annual period, with peaks in May and November. A deeper ASL allows the gyre's expansion and intensification, and enhances the westward throughflow. On the eastern side of West Antarctica, warm Circumpolar Deep Water (CDW) inflows to the Amundsen Sea are studied with a regional model and in situ data. The key inflow-­‐controlling mechanisms are identified by decomposing CDW temperature variability into two components associated with (1) changes in the depth of isopycnals (heave; HVE), and (2) changes in the temperature of isopycnals (water mass property changes; WMP). In the western Amundsen Sea, the deeper thermocline and shallower shelf break hinder CDW access onto the shelf, and CDW inflow is regulated by the uplift of isopycnals at the shelf break - which is itself controlled by wind-­‐driven variations in the speed of an undercurrent flowing eastward along the continental slope. In contrast, the shallower thermocline and deeper shelf break in the eastern Amundsen Sea permit CDW to persistently access the continental shelf, and CDW temperature in the area responds to wind-­‐driven modulation of the water mass' on-­‐ shelf volume by changes in the rate of inflow across the shelf break and in Ekman pumping-­‐ induced vertical displacement of isopycnals within the shelf. A multi-­‐year mooring located in the Dotson Trough (western Amundsen Sea) supports our model-­‐based conclusions. This mooring shows a transition to cooler conditions between 2010 and 2015, associated with WMP induced by weakening winds at the shelf break. The ASL was identified as the main driver of the local winds. A deeper ASL favours strengthening of the easterlies, weakening the undercurrent and reducing access of CDW to the continental shelf. In turn, a shallow ASL favours strengthening of the westerlies, intensifying the undercurrent and increasing access of CDW to the continental shelf. Thus, the Amundsen and Ross Seas are connected by a coastal current accelerated during periods of deeper ASL, which favours the export to the Ross Sea of meltwater from the Amundsen Sea coast. A future change in the ASL strength could impact both regions, with consequences for the regional heat budget and melting of the ice shelves downstream.

Abstract: Blasting fragmentation influences the cost and productivity of downstream processes such as loading, hauling, crushing, and milling. Interaction between the rock mass and explosive energy determines blast outcomes. This research aims to enhance the understanding of the blasting process by examining key factors that influence blast outcomes specifically, the explosive strength, rock mass strength, and rock structures such as rock contacts and joints. The research estimates damage zones around blasthole and evaluates fragmentation patterns using the analytical approach and numerical simulation. These methods are applied to the data from an existing mining operation collected through laboratory tests and field measurements. The results are validated through comparisons with field measurements and estimations from other verified approaches. Key findings of the research indicate that explosive selection is a crucial aspect of blast design and should be based on the rock mass properties and the desired outcomes. The formation and size of damage zones around the blasthole are influenced by the explosive’s energy and rock mass strength. Stronger explosives are more effective in hard rock, creating longer and more extended fractures, while less powerful explosives result in a more uniform distribution of fractures in both soft and hard rocks, although with a reduced extent in hard rocks. Structural properties influence how explosive energy and fractures are distributed in the rock mass. The propagation of stress waves at the interface between different rock types depends on the impedance difference between the rocks, the intensity of the incident stress wave, and its direction. When a stress wave moves from soft to hard rock, it is enhanced and attenuates in the opposite direction. Despite this attenuation, cracks can easily propagate from hard rock to soft rock. In a jointed rock mass, the type and size of the infill material, along with fracture frequency, significantly impact how explosive energy and fractures are distributed. When comparing empty joints with clay-filled joints, the empty joints reflect most of the stress wave energy, whereas clay-filled joints allow better energy transfer. Energy transmission decreases as joint width and fracture frequency increase, leading to reduced fracturing: by 9% when fracture frequency increases from one to four and by 13% when joint width increases from 3 to 10 cm. Other factors like joint continuity, distance from the charge, and joint orientation and randomness further intensify these effects. Blast design is the art of carefully balancing explosive strength, energy propagation, and confinement to maximize rock fracturing. This is achieved by selecting explosives that match the rock's strength and adjusting the pattern design and initiation sequencing and delays to maximize energy usage. Understanding how rock mass properties influence blast outcomes allows for better design adjustments. Common adjustments include changing explosive strength properties, increasing the powder factor, changing the pattern size, and varying initiation sequences and delays. The study found that increasing the powder factor by increasing the blasthole diameter did not improve fracturing in jointed rock masses. However, altering delays and sequencing significantly enhanced fracturing: 10% in intact rock, 14% in jointed rock, and 7% at rock contacts. The research is valuable to the industry as it provides practical guidelines for blast design, particularly in complex rock masses where standard approaches may be insufficient. The insights gained offer a basis for refining predictive models and exploring innovative blasting techniques.

The emissions of ammonia (NH3), particulate matter (PM2.5), and carbon dioxide (CO2) are major concerns in poultry facilities. They can pose environmental concerns and nuances. Robust and affordable measurement systems are needed to accurately measure in-barn concentrations and quantify the emissions. The Intelligent Portable Monitoring Unit (iPMU or PMU3) developed in 2016 was reconstructed into PMU4 to include upgraded NH3 and PM2.5 sensors and wireless connectivity for a low-cost, robust, and accurate air quality monitoring device with contactless data transfer using the concept of Internet of Things (IoT). In addition, a user-friendly web-based interface was developed for 1) real-time and historical data visualization, and 2) estimation of NH3 and PM2.5 emissions with suitable ventilation measurement. The PMU4 device developed in this project features back-up data stores and leverages cloud computing for data analysis and visualization. It was designed to collect and store sensor data (temperature, relative humidity, NH3, PM2.5, and CO2) on an SD card, and simultaneously send the data to a secure server. The PMU4 device uses Wi-Fi for internet access, but it was programmed to tolerate internet outages by queueing data and automatically transmitting the data queue to the secure server when the internet restores. The PMU4 device was deployed in the Robert T. Hamilton Poultry Teaching & Research Facility (Iowa State University, Ames, IA) for 13 days (September 15 – September 27, 2023) for field evaluation. The results showed that the mean temperature and relative humidity were 23.2 ± 1.8 ˚C and 62.1 ± 11.8% respectively. The mean concentrations of NH3, PM2.5, and CO2 were 0.47 ± 0.27 ppm, 12.0 ± 12.6 µg/m3, and 581.3 ± 134.2 ppm. The NH3 and PM2.5 per bird emission rates for the monitoring period were estimated using facility temperature, NH3 and PM2.5 concentrations, atmospheric barometric pressure obtained from the nearest airport, and ventilation and chicken inventory obtained from the facility manger. The mean per bird emission rates for NH3 and PM2.5 were 0.23 g/d/hen and 7.44 mg/d/hen, respectively. Advisor: Yijie Xiong

The focus of the first program, for violin and viola duo, is the celebration of virtuoso works for this relatively lesser performed ensemble. The repertoire presented follows the development of the violin and viola duo from a traditionally amateur environment to that of the concert stage. Each of the four duos, from Mozart to Bohuslav Martinu, demonstrates how the collaboration of two such closely related instruments yields remarkably rich results no matter what the period or harmonic vocabulary. Every piece presented in this recital displays a unique style of virtuosity, each one reflecting the composers’ different philosophical concepts of performance. Indeed, in every one of the duos, the listener witnesses new, groundbreaking approaches to virtuosity which will prove essential in the development of chamber music composition throughout the centuries. The second recital draws exclusively from the work of three twentieth-century composers, Igor Stravinsky, Paul Hindemith, and Alfred Schnittke, each of whom leveled the post-Romantic playing field, as it were, and pressed forward with the development of entirely fresh, autonomous, and innovative musical languages in response to the mercurial aesthetic and philosophical climate of their day. The program revolves their different approaches to early 20th Century Neoclassicism, following Hindemith and Schnittke’s references to Bach, and Stravinsky’s arrangement of his Neoclassical ballet Le Baiser de la Fée. The third recital was performed at the Chicago Cultural Center as part of the Dame Myra Hess Recitals, and was broadcast on WFMT. The performance was associated with a separate recorded lecture, which can be accessed at https://www.youtube.com/watch?v=feUimKL4q00. Its program is constructed around the fascinating nexus both among and between the charismatic Robert Schumann, his equally famous (if not even more so) wife Clara Wieck Schumann, and the young Johannes Brahms in the period just prior to Robert's confinement and demise. Focusing on Clara’s influence on the compositional style of the triumvirate, the program also follows the deep friendship that the three composers maintained with the famous virtuoso Joseph Joachim. All three works, for violin and piano, are representative of their mutual commitment to the concepts of Werktreue and transcendent, "poetic" virtuosity.

Abstract: Equipment selection is one of the most important decisions made in mine planning. Size of equipment affects decisions from size of pit to total cost of operation. There are some factors in equipment size selection which are currently incorporated into mine planning process and others are not. This study analyses hauler scale impacts on aspects not incorporated into conventional mine planning including expansion of roads to accommodate larger equipment, road layer thickness variation depending on hauler size, the rate of increase of rolling resistance and fuel consumption and emissions. Results obtained indicate a huge impact in cost and therefore their consideration in mine planning is highly recommended.