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The anthropogenic and natural input and transport of particulate organic carbon (POC) into and along stream systems from land to ocean is not yet well described (Regnier et al, 2013). Accelerated soil erosion due to changes in land use (e.g. expansion and intensification of agriculture) contribute to POC transport from land to ocean, while artificial damming of river systems, such as hydropower, trap the suspended particulate fractions and contribute to limnic storage in reservoirs. These perturbations on the landscape impact the volumes, transport and fate of suspended organic material. While mainly geomorphic processes control erosion and deposition of inorganic sediments, the mobility and transformation of POC is further subject to within-catchment stabilisation processes, sequestration by burial into sediments, and microbial fermentation which contribute to the vertical emission of potent greenhouse gases like CO2 and CH4. These sources, sinks and transformations of POC along the land-ocean aquatic continuum (LOAC) are dynamic and depend on input, transport, and deposition of suspended organic materials. Particulate organic carbon dynamics has been studied broadly in the past, both in freshwater systems, estuaries and oceans. However, its role in the global carbon cycle has been highlighted especially in recent years due to the lack of quantifiable pathways of POC sequestration, transport and mineralisation in freshwater systems. This project studied POC in two contexts: 1) POC transport and fate in a tropical reservoir was modelled and measured, and 2) the effects of flocculation on riverine DOM was measured by experiments. In the first study, erosion rates were calculated from fallout radionuclides (FRN) in a highly perturbed and largely deforested tropical catchment in Brazil. The results from these field observations were used to quantify soil erosion and sedimentation in the catchment. The results also validated modelled output with Revised Universal Soil Loss Equation (RUSLE) which was used to model soil erosion for the whole catchment. The contribution of allochthonous organic carbon from catchment soils into the reservoir was then quantified. The second study utilized the same field site, and addressed the relative inputs of allochthonous and autochthonous POC into the reservoir. Physical and chemical protection of organo-mineral aggregates and flocs determine the fate of catchment-derived POC. This second part of the study investigated whether allochthonous POC derived from terrestrial soils was more important than autochthonous POC (e.g. from macrophytes, biofilms and algae) for limnic storage in post-flooding sediments of a tropical reservoir. POC was calculated from C inventories of reservoir sediment cores collected along the delta-reservoir gradient and linked to organic matter content by loss on ignition (LOI). POC sources were determined by analysis of carbon-nitrogen ratio (C/N). Finally a POC budget was calculated for the post-flooding reservoir sediments. The third part of this project investigated flocculation dynamics of riverine organic matter in the LOAC. Flocculation experiments were undertaken to determine the effects of three treatments with coagulants on water DOM quality from eight streams draining a rural landscape with headwaters in Exmoor, UK. Through flocculation experiments stream samples were reacted with added clay and salt standards which simulated three flocculation boundaries along the LOAC. The three treatments were T1: increased input of minerogenic coagulants, such as clay, by soil erosion into streams, T2: saline mixing at the estuarine boundary, and T3: a mixture of salt and clay representing soil erosion at the estuarine boundary. Residual DOM quality by each treatment was analysed by mass spectrometry, UV-Vis absorbance and synchronous fluorescence. The results showed preferential removal of humic-like components in residual DOM and the efficiency of the chosen coagulant standards, which demonstrated the dynamics of chemical change in riverine organic matter along the LOAC.

Inland waters including streams, rivers, reservoirs and lakes are regarded as a significant site of Organic Carbon (OC) cycling, and greenhouse gas production. As a result, there has been significant recent interest in the rates and fate of fluvial carbon exported from organic soils, such as peatlands. Additionally, peatlands can be subject to substantial degradation resulting in high rates of fluvial OC export, and this has led to efforts to repair degraded peatlands through restoration programmes. As a consequence, the study of degraded areas is useful to quantify the upper values of carbon release, understand processes of transformation, and evaluate the success of restoration programmes. Importantly peatlands are also collection areas for drinking water, which has implications for treatment, and requires better understanding of carbon cycling upstream of treatment works, in headwater rivers, reservoirs and pipes. UK upland blanket peat catchments are a key location in which to consider global questions surrounding fluvial carbon export and transformations, as they are highly degraded, provide a source of drinking water supply, and are currently undergoing pioneering methods of landscape scale restoration. This thesis considers Kinder Scout, an area of highly degraded and gullied blanket peatland in the South Pennines, UK. Using analysis of water samples collected over several years in the Kinder reservoir catchment and plateau, this thesis presents three novel contributions to global questions concerning OC cycling and peatlands. Firstly it provides (to date), the only carbon budget for a reservoir in a peat dominated catchment with high Particulate Organic Carbon (POC) export, which demonstrates that reservoirs may be net sources of Dissolved Organic Carbon (DOC), with the implication that POC-DOC interactions are important OC transformation mechanism in degraded systems. Secondly through use of a unique integrated combination of methods, it considers changes in carbon flux and composition in both river, lake and pipe locations, providing detailed understanding of the relative roles of river reaches, reservoirs and supply pipes, in controlling fluvial carbon cycling in peatland systems, and upstream of water treatment works. An important implication here, is that rate and direction of change in water treatability varies through a catchment. Finally, it includes results from the first widespread monitoring of the catchment scale effects of a new method of peatland revegetation. This restoration approach is being applied at landscape scale and the findings here, are that despite fears to the contrary, it does not lead to short term increases in fluvial carbon loss, which is an important piece of evidence supporting practical conservation approaches in these systems. To further enhance this research, a combination of field and laboratory investigations into carbon transformation processes, and ongoing restoration mentoring should be undertaken.

This paper examines the evolution of digital comedy through a comparative analysis of CollegeHumor and its offshoot, Dropout.tv, focusing on how each platform has approached the portrayal of diversity and inclusion. Utilizing a qualitative content analysis, the study contrasts selected episodes from both platforms to explore shifts in the representation of queer and POC comedians, and the thematic treatment of identity issues. The findings reveal that Dropout.tv significantly advances the inclusivity of comedic content, moving beyond CollegeHumor’s earlier reliance on stereotypical and controversial humor. This shift not only reflects changes in contemporary comedy but also highlights Dropout.tv's commitment to fostering a diverse and thoughtful comedic environment. The study proposes further research into audience perceptions to deepen understanding of digital comedy's impact on societal attitudes towards diversity and inclusion.

The scale-up of hepatitis C virus (HCV) diagnosis and treatment requires affordable and simple tools to improve access to care, especially in low- and middle-income settings with limited infrastructure or high-risk populations. Dried blood and plasma samples (DBS and DPS) are useful alternative for hepatitis C detection in settings lacking adequate infrastructure. We evaluated the performance of DBS and DPS vs plasma in a point-of-care HCV RNA quantitative assay (Xpert HCV Viral Load-Cepheid), and compared HCV core antigen (HCVcAg) detection by the Architect HCV core antigen assay (Abbott) in DBS vs serum. The dried samples were stored at room temperature for different storage times to reproduce the time from sampling to testing in settings with centralized diagnosis or when testing mobile populations. HCV RNA quantification in DBS and DPS presented 100% sensitivity and specificity and a high correlation for up to 3 months of storage. HCV viremia showed a mean decrease of 0.5 log(10) IU/mL (DBS) and 0.3 log(10) IU/mL (DPS) for storage times up to 1 month. Architect HCVcAg detection presented high sensitivity/specificity (96%/100%) in DBS tested immediately after sampling, decreasing to 86% sensitivity after 7 days of storage. However, sensitivity increased when an optimized cut-off was applied for each storage time. We conclude that DBS and DPS are suitable samples for HCV RNA detection and quantification, being DPS more reliable for shorter storage times. DBS can be also used for HCVcAg qualitative detection and the sensitivity can be increased when adjusting the cut-off values. IMPORTANCE Hepatitis C infection remains a global burden despite the effectiveness of antivirals. In the WHO roadmap to accomplish HCV elimination by 2030, HCV diagnosis is one of the main targets. However, identifying patients in resource-limited settings and high-risk populations with limited access to healthcare remains a challenge and requires innovative approaches that allow decentralized testing. The significance of our research is in verifying the good performance of dried samples for HCV diagnosis using two different diagnostics assays and considering the effect of room temperature storage in this sample format. We confirmed dried samples are an interesting alternative for HCV screening and reflex testing in resource-limited settings or high-risk populations.

Digital contact tracing offers significant promise to help reduce the spread of SARS-CoV-2 and other viruses. Google and Apple joined together to create the Google/Apple Exposure Notification (GAEN) framework to determine encounters with anonymous users later diagnosed COVID-19 positive. However, as GAEN lacks geospatial awareness, it is susceptible to geographically distributed replay attacks. While the replay attack is generally known, we contribute a new proof-of-concept for an easily deployed, anonymous, low-cost, crowd-sourced replay attack network by malicious actors (or far away nation-state attackers) who utilize malicious (or innocent) users’ smartphones to capture and replay GAEN advertisements that drastically increase false-positive rates even in areas that otherwise exhibit low positivity rates. In response to this powerful and feasible replay attack, we introduce GAEN+, a solution that enhances GAEN with geospatial awareness while maintaining user privacy, and demonstrate its ability to effectively prevent distributed replay attacks with negligible overhead compared with the original GAEN framework.

* “Chó bò” is the approximate Vietnamese homonym for “trouble.” Bluntly translated, “chó~bò” is a “dog~cow” or “dog~crawl.” This absurdist linguistic joke for many Vietnamese people learning English represents a capacity to make trouble. This PhD thesis comprises original research and artistic work made with my family. As people from the Vietnamese diaspora, our experiences are formed by dispersals and estrangements as settler-colonists in Australia. Our daily encounters in the realms that this thesis is focused – contemporary art, academia, and family enterprise, are folded into distinct systems of colonial power and violence. I often make work with my family in video-performance and the documentary medium. Our inter-generational, political, and language differences add to the conceptual complexity of what it means to collaborate, make art, produce archives, and confront our position as recent settler-colonisers in Australia. This thesis aims to address how our artistic collaborations utilise linguistic and archival approaches to articulate the systemic racism we encounter as people from a refugee background, but who are also embedded in the colonial infrastructures of our new home. Aligning with thinkers including Gloria Anzaldúa and her critique of coloniality, to Gayatri Chakravorty Spivak and Hito Steyerl on minoritarian forms of translation, and Sara Ahmed on racism in the university - this thesis describes how collaborations with my family can trouble the contradictions of colonial power enacted on our human relationships. Reconnecting with individual members of my family through art, I have gained a better understanding of my language and culture, as well as finding important artistic and political connection to my peers. Collaborating with my family has forced me to rub against the researcher-participant/research subject binary, the archival visibility of being invisible, the rhetoric of institutional inclusion, and the weight of being displaced and displacing colonisers on this continent. The work we have produced together methodologically uncovers and critiques the opaque confrontations of institutional power, racism, and colonial violence embedded in the everyday. As a family, we continue to make uncomfortable pronunciations like “chó bò,” producing the epistemic trouble needed to face the colonial realities of our resettlement. ARTWORK WEBSITE: https://chobotrouble.com/

Every year infectious diseases are among the top major causes of death worldwide. Infectious diseases disproportionately impact resource-poor areas. While most developed countries have the ability to screen and quickly detect infectious diseases in humans, animals, and plants, developing countries lack this ability. In such areas, access to medical treatment and testing facilities is severely limited. Additionally, developing countries are more densely populated, which makes infectious disease surveillance exceedingly more difficult. As a result of this, infectious diseases tend to spread more quickly and outbreaks tend to occur more often in developing countries. Additionally, the increasing rate of antimicrobial resistant infections and emergence of novel infectious diseases increase the likelihood of global pandemic occurrence. It is evident that developing novel devices for detection of infectious diseases would be greatly beneficial to global health. It is important to note that developed countries would benefit equally from such a device. Pandemics tend to burden the economy and put strain on resources even in developed countries. The impact of such a device is determined by a set of criteria put forth by the World Health Organization (WHO). Based on the ASSURED criteria, an ideal device for point-of-care (POC) diagnostics must be affordable, sensitive, specific; and yet it must also be user-friendly, rapid and robust, equipment free, and deliverable to end-users. Additionally, this device must be easily adaptable for detection of novel pathogens. The nucleic acid amplification test (NAAT) meets many of these criteria. However, NAAT’s current workflow involves many user liquid handling steps as well as a thermocycler. This thesis aims to address these issues by first automating isothermal nucleic acid amplification, followed by coupling the amplification step with the lateral-flow immunoassay (LFA), which is a paper-based diagnostic device. Thus, taking advantage of the affordability and POC features of the LFA. The aim of these efforts is to work toward the ultimate goal of developing a device that receives the patient sample, then carries out all the steps in NAAT in an automated manner and produces results with just a push of a single button.

In this era of technological transformation in medicine, there is need to revolutionize the approach and procedures involved in the treatment of diseases to have a restructured understanding of the role of data and technology in the medical industry. Data is a key factor in diagnosis, management, and treatment of patients in any medical institution. Proper management and usage of patient’s data will go a long way in helping the society save money, time and life of the patient. Having data is one thing and providing a system or means of translating the data is another issue.This dissertation is proposing a design of a Point of Care system for the Intensive Care Unit (a.k.a ICU_POC), which is a system that integrates the capabilities of the bedside monitors, bedside eFlowsheet and the Electronic Medical Records in such a manner that the clinicians interact with one another in real time from different locations, to view, analyze, and even make necessary diagnoses on patients’ ailment based on their medical records. It demonstrates how patient data from the monitors can be imported, processed, and transformed into meaningful and useful information, stored, reproduced and transferred automatically to all necessary locations securely and efficiently without any human manipulation.ICU_POC will grant physicians the remote capability in managing patients properly by providing accurate patient data, easy analysis and fast diagnosis of patient conditions. It creates an interface for physicians to query historical data and make proper assumptions based on previous medical conditions. The problem lies in managing data transfer securely between one hospital EMR database and the other for easy accessibility of data by the physicians. This work is challenged by designing a system that could provide a fast, accurate, secure and effective (FASE) diagnosis of medical conditions of the patients in the ICU. The proposed system has the potential of reducing patients’ length of stay in the ICU by equipping the physicians with an easy way of managing patients’ data seamlessly and diagnosing conditions quickly. This, in turn, will reduce the cost of care generally in the society.

Climate-linked changes in hydrology and biogeochemical processes within Arctic watersheds are likely already affecting fluvial export of waterborne materials, including organic matter (OM) and dissolved inorganic nitrogen (DIN). Our understanding of Arctic watershed OM and DIN export response to climate change is hampered by a lack of contemporary baselines, as well as a dearth of seasonally comprehensive studies. This work focuses on characterizing OM and DIN concentrations and sources in six streams/rivers on the North Slope of Alaska during the entirety of the hydrologic year (May through October) in 2009 and 2010. The highest OM concentrations occurred during spring snowmelt, with results indicating that terrestrial vegetation leachates are the major source of dissolved OM, while particulate OM originates from a degraded soil source. Over the hydrologic year, soils became a progressively increasing source of dissolved OM, while autochthonous production made up a sizeable proportion of particulate OM during base flow conditions. DIN concentrations were low throughout the spring and summer and increased markedly during the late summer and fall. Our findings suggest that penetration of water into thawed mineral soils, and a reduction in nitrogen assimilation relative to remineralization, may increase DIN export from Arctic watersheds during the late summer and fall. Although recent studies of Arctic rivers have emphasized the importance of the spring thaw period on OM export, our understanding of the mechanisms that control water chemistry observations during this time are still lacking. Experimental leaching results, from experiments conducted in 2014, suggest that aboveground plant biomass is a major source of dissolved OM in Arctic catchments during the spring, and that the timing of freezing and drying conditions during the fall may impact dissolved OM leaching dynamics on that same material the following snowmelt. Improved knowledge of OM and DIN temporal trends and the mechanisms that control seasonal concentrations is essential for understanding export dynamics of these water constituents in Arctic river systems. Perhaps more importantly, increased understanding of the seasonal controls on OM and DIN export in Arctic rivers is critical for predicting how these systems will respond under future climate change scenarios.

The development of patterning high-resolution microfluidic circuits onto cellulose paper in 2007 initiated widespread research into the use of the paper as a low-cost, easy-to-use alternative substrate over the glass and plastics of traditional microfluidics. Paper, as a porous hydrophilic material, naturally wicks fluid through itself, without the need to external pumps or power sources. The patterning of paper into hydrophobic and hydrophilic regions, now achievable with consumer-grade office printers, allowed the design of new 2D devices, capable of multi-analyte detection. 3D devices, made from multiple stacked layers of paper, offer even more possibilities for complex, multi-fluid routing in smaller overall device footprints. The use of patterned aerosol adhesives are investigated as an improved method of attaching multiple paper layers together rapidly and with minimal interference of interlayer fluid transport. Patterned aerosol adhesives also enable the development of nonplanar 3D devices, which represent a novel platform upon which to develop new microfluidic devices, which would otherwise be impossible to construct or function in a planar device.Much of paper microfluidics research is focused on developing more sophisticated detection methods that provide quantitative data, instead of simple colorimetric qualitative yes/no answers. Frequently quantification is obtained by scanning the device and performing a color intensity analysis to relate a color change to concentrations of a target analyte. This technique suffers due to variations in the quality of imaging equipment and the ambient lighting conditions during image acquisition. To address this, some have proposed a distance-based lateral flow device, where the distance traveled by a colored substance is proportional to the target analyte concentration. The use of a microsphere aggregation-based sandwich assay was investigated for semi-quantitatively determining the concentration of a target ssDNA strand.

Gay, bisexual, lesbian, transgender, questioning/queer, and ally (GBLTQA) programming and spaces at predominately White universities often struggle to meet the needs of GBLTQA students of color. Findings from questionnaire results, interviews, and focus groups demonstrate many of the factors that prevent GBLTQA programming and spaces from increasing inclusion. The main goal of this research is to explore the current problems that exist in terms of race in the Wright State University GBLTQA campus community. I will then discuss strategies that GBLTQA organizations and higher education administrators can employ to increase representation of GBLTQA students of color in programming, resources, and spaces.

Abstract: Poly(N-isopropylacrylamide) (pNIPAm) microgel-based etalons are photonic materials that exhibit color based on temperature or other environmental stimuli. These materials provide a new and unique method for biosensing and other applications. Therefore it is important to understand these materials and to continue developing the materials in order to realise their full potential. This work examines the development of these materials in point-of-care (POC) diagnostics by exploring new and less expensive materials for etalon fabrication as well as examining the volume phase transition temperature of pNIPAm microgels and how it’s affected by confinement in the etalon. It was found that the metal used in fabricating the device did not have a significant impact on the optical properties of the device. Additionally it was determined that the volume phase transition temperature (VPTT) of the microgels was not affected by their confinement in the device, and a VPTT was measured at methanol concentrations where no transition was previously observed.