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Mycobacterium avium subspecies hominissuis Adaptation to Diverse Environments
No full textM. avium subsp. hominissuis (M. avium) is clinically important non-tuberculous mycobacteria (NTM) that infect immunocompromised patients with AIDS and individuals with underlining chronic lung conditions such as bronchiectasis or cystic fibrosis. M. avium is capable to adapt to an array of environments with different oxygen levels, various sources of oxidative stress and paucity of nutrient. The high versatility and pathogenicity of this bacterium have been attributed to several virulence factors and the ability to tolerate to exogenous stresses.
Tolerance to oxidative stress is likely to make a significant contribution to the survival of M. avium, even in the presence of ROS, such as superoxide (O-2), hydrogen peroxide (H2O2), and hydroxyl radical (OH). The pathogenesis mechanisms, however, modulating the macrophage killing mechanisms are not fully understood. To better appreciate M. avium virulence factors, we have discussed the roles of MAV_3616, MAV_2941, MAV_2928 as well as other virulence-related genes of M. avium. In addition, we have also analyzed M. avium enzymes such as superoxide dismutases (SOD), catalases (CAT), and akylhydroperoxide reductase, and small protein molecules such as thioredoxin in reducing reactive oxygen species (ROS) production by macrophages.
The main challenge of treating M. avium patients is an inability to rapidly kill pathogens even with multiple compounds at bactericidal concentrations. The main goal of our research is to investigate M. avium proteome response under the microenvironments encountered in human host tissues, including aerobic, anaerobic and biofilm conditions. Under these unfavorable environmental conditions, M. avium maintains a slow growth state, becoming many times tolerant to antibiotics. A low metabolic state during stress conditions is a common response observed in M. avium infection, by altering their metabolism and minimizes the synthesis of specific metabolic proteins. Identifying proteins that are expressed within different environmental stresses will help to understand what metabolic pathways M. avium uses under conditions encounter in the host.
Overall, 3720 proteins were identified out of 5313 MAH proteomes across all the studied conditions. The incubation under anaerobic and biofilm conditions resulted in enrichment of 168 and 280 proteins, respectively, in comparison to aerobic conditions. Several metabolic pathways were found commonly expressed in both anaerobic and biofilm conditions, including, glycerolipid metabolism, chloroalkene degradation and degradation of aromatic compound pathway. While other pathways associated with macromolecular biosynthesis machinery such as fatty acid metabolism and amino acid metabolism were found to be significantly expressed under biofilm conditions. Overproduction of MAV_0344, MAV_3180, MAV_3185, MAV_3413, MAV_3415, MAV_3428 of biosynthesis of amino acids pathway and upregulation of MAV_2438 oxidoreductase, short chain dehydrogenase/reductase family protein, MAV_2945 enoyl-CoA hydratase/isomerase family protein and MAV_3944 putative acyl-CoA dehydrogenase of fatty acid metabolism was observed during the formation of M. avium biofilm.
Our study identified protein determinants responsible for M. avium biofilm and anaerobic bacterial tolerance. These results can be utilized to develop novel strategies to target antibiotic-tolerant M. avium, with the goal of shortening the duration of treatment and influence survival in patients with M. avium
Safety and User Perceptions of Auxiliary Bike Lanes
No full textThis data contains the survey responses used to explore the safety and user perceptions of auxiliary bike lanes as posed in “SPR869 – Safety and User Perceptions of Auxiliary Bike Lanes.” Data includes two datasets corresponding to each survey by user perspective: drivers and cyclists. In each data set are the responses from the three video-question pairs, including Likert-scale and open-ended response questions, and the questions regarding user perceptions. The data also includes demographic and relevant road user experience, as a driver and/or cyclist, data
Public Policy Barriers to Carbon Capture and Storage in California
No full textMany industries in California are difficult to decarbonize, making carbon capture and storage (CCS) essential to reach net zero. California has committed to deliver an enormous 100 thousand tons per year of carbon storage by 2045. Despite much interest in carbon sequestration, there are currently no active geologic carbon capture and storage (GCCS) projects and one direct air capture (DAC) plant in California. As there is no natural market for carbon dioxide (CO2), government is a first mover in developing carbon capture projects. The questions asked in this paper are: What are the public policy barriers to carbon capture projects in California, what can public policy recommend to scale up to meet the state’s goals, and what are options for the government’s role in carbon capture projects? This paper considers the current policy supports for GCCS in California, including existing and proposed legislation, and proposes solutions to barriers in each of the four categories of financial and cost problems, technical problems, political questions, and real-world execution challenges. Because CCS projects consist of the three streams of carbon capture, transport, and storage, business uncertainties are compounded. The paper concludes that two primary policy levers to achieve California’s commitment would be for government to decrease uncertainty by frontloading construction of pipeline infrastructure, similar to the UK’s transport and storage business model; and to develop new legislation that empowers an existing agency or otherwise develops a new approach to transport and storage governance, and establishes a new carbon economy. For CCS to provide 25% of California’s net zero solution, robust processes seem warranted
Physically modeling simplistic lattices : testing the fibrous nature of extracellular matrices
No full textAn intrinsic aspect of the human body regards the fundamental application of cellular mechanics. Things like cell growth and movement stem from the extracellular matrix (ECM) which acts as a complicated biopolymer network. Further research regarding ECMs relates to tissue engineering applications and thus plays a key component in cellular growth, development, and regeneration. In this project we look to better develop our understanding of the mechanical structures of extracellular matrices. Currently, ECM understandings have produced advanced technologies in biomedical efforts and are found to be useful in a large accumulation of different areas of expertise. Our research is focused on the physicality of tissue mechanics through experiment examination based on the structure heterogeneity of simplistic models. Assuming a hyper-simplistic model, a 3D printed hexagonal structure is built to quantify our understanding of Maxwell's criterions foundations. We use our models to sample stress-testing and the effective applications of such, to reveal novel material properties in complex cellular fibres
Too Hot to Handle: Impacts of increasing temperatures on early life history stages of Tiger Grouper (Mycteroperca tigris) from Little Cayman, Cayman Islands
No full textThe early life history stages of fish are typically the most sensitive to environmental change, particularly regarding temperature. With tropical ocean temperatures projected to increase over the next fifty years, documenting how the development of larval fishes changes under different temperature regimes is crucial to understand how these changes will affect population dynamics. Tiger Grouper (Mycteroperca tigris) is an economically and ecologically important reef fish distributed throughout the Caribbean that aggregates to spawn during colder winter months. We collected embryos from spawning events on the west end of Little Cayman, Cayman Islands, using established techniques from the Grouper Moon Project, and reared embryos and larvae at 25°C and 27°C (within current temperature variability) and 29°C and 31°C (within predicted elevated temperatures in the next 100 years) for up to three days. Embryos and larvae were photographed, and measurements of various morphometrics were taken (i.e., standard length, total length, oil globule diameter, yolk sac diameter, body depth, etc.) at 1 -, 2-, and 3- days post fertilization (dpf). Rates of embryo ascension for Tiger Grouper embryo groups at different hours post fertilization (hpf) were measured.
Due to the allocation of embryos into treatment groups resulting in uneven sample sizes, this study draws from qualitative data of the photogrammetry process with some support from statistical analysis. Kruskal Wallis and Dunn’s tests were performed for each growth measurement along with the embryo ascension rates; for the body measurements, only samples from 2 dpf were statistically analyzed. There were few statistically significant p-values returned from the Kruskal-Wallis test, with the only statistically significant difference being between MDV measurements (p < 0.05) (Figure 5, E); however qualitative analysis of the temperature treatments and subsets suggests negative impacts of increased temperature on their development. The qualitative analysis suggests faster absorption of yolk sacs and oil globules occurred at higher rates in the elevated temperature groups of 29°C and 31°C, possibly due to increase metabolic rates from the increased temperature, which would direct energy away from growth and towards combating the effects of temperature. Recommendations for future research repeating similar studies on Tiger Grouper with a larger sample size and comparing their anatomical development and ascension rates with closely related species. In addition to this, the reevaluation of the Tiger Grouper conservation status would be of high priority, as this can best inform how future management of this species changes in addition to the impacts of climate change on the area.Keywords: Climate change, Biology, Tiger Grouper, Fish Early Life Histor
Modeling the habitat occupancy and abundance of salmonid ectoparasite Salmincola californiensis in Willamette Valley reservoirs
No full textThe freshwater copepod Salmincola californiensis is an ectoparasite of Pacific salmonids (Oncorhynchus spp.) Threatened and endangered salmonids that rear in the reservoirs have been reported to experience higher rates of infection by S. californiensis than would be experienced by their stream-reared counterparts. These high levels of infection can lead to decreased fish fitness and survival that might ultimately hinder salmon recovery efforts. To date, the relationship between reservoir environmental conditions and infection rates is poorly understood. This research aimed to evaluate sampling methods designed to catch the infectious lifestage of the copepods and to develop predictive models of the distribution and abundance of S. californiensis in relation to pertinent environmental factors (e.g., temperature, water clarity, reservoir plankton profiles, and season) in three Willamette Project reservoirs. During five months in 2020, we used light traps to collect nearly 700 zooplankton samples from various sites and depths in Cougar, Lookout Point, and Fall Creek reservoirs, Oregon, USA. These samples were searched for S. californiensis, and this information was paired with concurrently measured environmental data to create occupancy and abundance models. Our models showed a strong influence by water temperature on copepodid habitat occupancy and abundance of the free-swimming stage of S. califoniensis, with maximum occupancy and abundance occurring at 15.2 °C. Mean site occupancy probability in August was 0.75 for all reservoirs and mean August abundance was 92.5 copepodids per site in Cougar reservoir, 62.1 copepodids per site in Fall Creek, and 1.9 copepodids per site in Lookout Point. The efficacy of our sampling method was influenced by ambient light at depth, water temperature, and number of juvenile sculpin (Cottus spp.) nearby. Trap efficacy ranged from 34% when ambient light was low to 89% when ambient light was high. Information gained from this work will be useful for guiding management decisions made by biologists and dam operators regarding salmonid populations in the region
A Sweet Solution for Spotted-wing Drosophila: Evaluating the Potential and Non-target Impacts of Erythritol for Integrated Pest Management
No full textSpotted-wing drosophila, or Drosophila suzukii (Diptera: Drosophilidae) (Matsumura), is a vinegar fly native to Southeast Asia. A combination of management practices is used to control this pest, but new strategies aim to decrease pesticide use with preventative methods and targeted treatments. The artificial sweetener erythritol is a novel candidate for spotted-wing drosophila control because it causes dose-dependent mortality, deters oviposition, and is nontoxic to vertebrates and many beneficial insects. 1.5 M erythritol is combined with a phagostimulant of 0.5 M sucrose (E:S) or 0.1 M sucralose (E:Sul) to create an insecticidal solution. However, field trials prior to this thesis observed damage on blueberry and cherry leaves resulting from erythritol treatments. The purpose of this thesis was to quantify this damage and its effects on plant physiology, add to research on efficacy of erythritol solutions for spotted-wing drosophila control, and characterize the effects of these solutions on the parasitoid Ganaspis brasiliensis (Hymenoptera: Figitidae) (Ihering) [recently renamed Ganaspis kimorum Buffington], a candidate for biological control.
We investigated the extent of visual damage and impacts on plant physiological characteristics of stomatal conductance, photosynthesis, and intracellular water and solute content in blueberry (Vaccinium corymbosum ‘Duke,’ ‘Reka’), cherry (Prunus avium ‘Corum’), and wild Himalayan blackberry (Rubus armeniacus) systems. In 2022, four combinations of bulk or laboratory-grade erythritol with 0.5 M sucrose or 0.1 M sucralose, plus a water control, were tested in a blueberry field, a cherry field, and wild Himalayan blackberries. Potted blueberries were treated with a 2.0 M erythritol concentration to exacerbate physiological effects. Though leaf damage was greater at the higher erythritol concentration, damage did not vary consistently by treatment in any system. Treatments did not consistently affect any physiological characteristic. Our 2023 trials in a blueberry and cherry field evaluated the individual effects of erythritol and phagostimulants, and we re-treated blueberry plots from 2022 to assess multi-year effects. Leaf damage did not vary consistently by treatment, but higher solute concentrations caused greater damage. Treatments did not significantly affect any physiological characteristic, and no multi-year effects were found. These results suggest that the appearance of damage from erythritol does not necessarily correspond with physiological detriment, supporting erythritol’s potential as a method of spotted-wing drosophila control.
Infestation and oviposition trials evaluated the efficacy of E:S or E:Sul solutions for spotted-wing drosophila management. Infestation trials in a blueberry field and wild Himalayan blackberries sampled treated fruit and counted the number of spotted-wing drosophila adults or larvae. No differences in infestation were present between either treatment or a water control. Oviposition trials in a blueberry field used mesh bags around fruit clusters to protect from outside predation, then upon ripening the fruit was treated with an erythritol solution or control. Then, 10 female flies were introduced for 24 hours and the number of eggs was counted. In 2022, treatments had no effect on oviposition, but in 2023, E:Sul-treated berries experienced significantly lower oviposition than E:S or the control.
Non-target feeding by the imported parasitoid G. brasiliensis in the laboratory evaluated survivorship and parasitism by G. brasiliensis exposed to an E:S, E:Sul, 0.5 M sucrose, or water-only solution for 14 days. Exposure to E:Sul caused the quickest mortality, but this effect would likely be mitigated by nutritive carbohydrates, which are present in field conditions. Host parasitism was not affected by treatment. This thesis adds to existing knowledge about the efficacy and non-target effects of erythritol solutions for potential use in integrated pest management of spotted-wing drosophila
Financial Analysis and Strategy for an Energy Focused, Low Profit Margin Product Plan, Development, and Sale of a Versatile Durable Medical Motorized Chair
No full textMobility devices give people with disabilities freedom that allows them to function in society to their highest desired degree. While most wheelchairs are made for the purpose of mass production at a low cost or are specialized to give the user a higher quality of life at an exorbitant price, it is possible to build a system that creates innovative, advanced motorized wheelchairs at little to no cost to the end user. This paper determines a set of operational standards for a product that would allow the user to traverse virtually any terrain that an average, able-bodied person could navigate. This product would drastically extend the range that most motor wheelchairs can currently travel while adding robust auxiliary features. These capabilities rely heavily on the individual capabilities of the wheelchair’s chassis, suspension, electrical system, and user interface. By maximizing the product quality while minimizing cost, a device that can bypass the insurance system can directly benefit the user through the use of partnerships and tax benefits, leaving little to no cost for customers who are unable to pay full price.Key Words: Durable Medical Equipment, self-propulsion, assist-propulsion, chassis, suspension, pulse width modulation, deep-cycle, neurotypical, LCD display, social enterprise
Resource-Aware Distributed Data Sanitization for Privacy Preserving Machine Learning
No full textWhen a single object is captured by multiple edge devices, the data captured by every edge device could contain both public and private information. The private information in every copy of the data captured has to be preserved while the public information has to be utilized for any further machine learning tasks. We present a machine learning framework that achieves these two competing objectives in a distributed and resource constrained environment. In this work, we develop a data sanitizing algorithm as an interplay between the two competing objectives and address the problem of resource constraints by utilizing an iterative model pruning technique. To demonstrate the system’s performance, we conduct experiments on a custom MNIST dataset. We synthesize a two digit dataset of numbers in the range 00-19. Any even number in this dataset is considered as public information and any number in the range 10-19 as private information