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CARBON DIOXIDE ADSORPTION ON MOFS-COATED WIND TURBINE BLADES: MODELING AND FACTORS INFLUENCING ADSORPTION RATE
Get PDFThis thesis conducts a study on the utilization of porous Metal-Organic Frameworks (MOFs) materials for carbon dioxide adsorption on MOFs-covered wind turbine blades. A quantitative model for the adsorption rate is derived, which is later used to calculate the adsorption under typical turbine operation. Results show the adsorption rate may be as high as that of thousands of trees, making this application a very promising area for further research and possible commercialization. We also investigated the influence of various factors on the overall mass transfer rate, including the MOFs surface area per unit volume, thickness of the MOFs layer, assumed reaction rate coefficient, wind speed, and MOFs porosity. The overall adsorption rate result is influenced by the combined effect of these factors. Overall, this study demonstrates the potential of using MOFs materials for carbon adsorption on MOFs-coated wind turbine blades. The results of this study motivate and inform further research and development of this technology for practical applications to enable a net-zero carbon emissions future
IL-13 Modulates the Metabolic Phenotype of Interstitial Macrophages in Allergic Airway Disease
No full textAs the prevalence of asthma continues to rise, the need for an improved understanding of its etiology becomes increasingly urgent. Allergic asthma is a chronic airway disease characterized by a dysregulated type 2 immune response. Macrophages play a key role in establishing the immunological tone of the airways. However, a majority of the available data focus on the role of alveolar macrophages in lung inflammation, not interstitial macrophages (IMs). Though understudied, recent evidence suggests that IMs, which reside in the space between blood vessels and the airways, are involved in allergic asthma pathogenesis.
Cell metabolism is intricately linked to cell function. While a cell’s decision to perform one form of energy production over another is partly informed by substrate availability, a growing body of evidence suggests some functions are substrate-dependent. Metabolic phenotyping can offer insights into the processes governing cell function and behavior. Currently, no studies describe the metabolic phenotype of IMs in the context of airway allergy.
Here, the IMs of allergen-challenged mice exhibit a dual dependence on glucose and lipid metabolism, a phenotype not shared by any other of the evaluated lung immune cells. IL-13Rα1–expressing IMs are the primary drivers of this phenotype, implicating IL-13 as a possible contender in driving this metabolic shift. We also show that IM function is glucose-dependent, as blocking glucose metabolism impedes the uptake of the aeroallergen, house dust mite. Collectively, these data show that IL-13Rα1+ IMs adopt a unique metabolic profile in allergic airway disease and offer preliminary insight into the link between IM metabolism and function
Exploring the epitranscriptome as a molecular determinant of the testosterone paradox
Get PDFProstate cancer remains a leading cause of cancer-related mortality among men, with its progression heavily influenced by androgen receptor (AR) signaling pathways. The advent of supraphysiological testosterone (SupraT) treatment has brought forth the "testosterone paradox," where high levels of testosterone exert both stimulatory and suppressive effects on prostate cancer growth. The molecular mechanisms underlying this paradox are not fully understood, necessitating further investigation into the cellular and molecular dynamics at play. This study explores the impact of SupraT on the epitranscriptome, specifically m6A mRNA methylation, and its correlation with AR signaling dynamics. Central to the investigation is the interplay between SupraT and the fat mass and obesity-associated protein (FTO), examining its effect on epitranscriptomic changes. The research reveals that SupraT causes significant alterations in the epitranscriptomic landscape that affect gene expression patterns essential for the proliferation and survival of prostate cancer cells. These findings illuminate the nuanced role of AR or signaling in epitranscriptomic regulation via FTO, suggesting that targeting these molecular pathways could offer new therapeutic strategies for advanced prostate cancer treatment. The study not only sheds light on the underlying mechanisms of the testosterone paradox but also suggests the epitranscriptome as a promising target for future prostate cancer therapies
REIMAGINING EQUITY: OVERCOMING CAPITALIST FORCES TO TRANSFORM POLICY SSI INCOME LIMITS AND A CASE FOR UBI
Get PDFThis essay critically examines disability policy in the United States, focusing on the limitations of the Supplemental Security Income (SSI) program and proposing universal basic income (UBI) as a transformative solution. The analysis highlights how capitalist interests and elite capture perpetuate systemic inequities and marginalization among disabled individuals. While SSI aims to provide financial support to vulnerable populations, its stringent savings limits and inadequate benefit levels hinder economic autonomy and perpetuate cycles of dependency. Legislative efforts, such as the "SSI Savings Penalty Elimination Act," offer incremental reforms but fail to address underlying systemic issues. By evaluating means-tested benefits through core bioethical principles, including justice, autonomy, beneficence, and nonmaleficence, the essay argues for a comprehensive approach centered on UBI. UBI offers a pathway to economic autonomy, dignity, and empowerment for disabled individuals by providing unconditional support and mitigating elite capture. However, to ensure full economic autonomy, UBI+ should be considered, providing additional funds to meet the unique needs of disabled people
Characterizing the Role of Neutrophil Extracellular Traps in Staphylococcus aureus Infection
Get PDFStaphylococcus aureus is a Gram-positive, opportunistic pathogen that can cause infections in healthcare-associated and community-associated settings. These include skin and soft tissue infections that can disseminate through the bloodstream to deep tissue sites. Neutrophils constitute the first innate immune response to infection and neutrophil extracellular traps (NETs) formed by chromatin and associated proteins are implicated in many S. aureus disease states. In this study, we aimed to characterize the spatiotemporal expression pattern of S. aureus virulence factors and NETs during kidney infection, a clinically relevant site due to the impact of ascending urinary tract infections and indwelling medical devices.
We hypothesized that S. aureus expresses certain toxins which are regulated by two-component systems to either evade or hijack the NETosis response. We also hypothesized that NETs have a protective role during infection. We tested these using fluorescent transcriptional reporter strains of S. aureus and PAD4-/- transgenic mouse lines that cannot produce NETs. We focused on bi-component leukocidins and regulatory systems Sae and Agr. Through in vivo studies, we found high expression of agrB when bacteria are surrounded by NETs. This suggests a role of Agr in NET induction. In vitro, saeP and hlgAB (a Sae-regulated toxin) were highly expressed in bacteria entrapped in preexisting NETs. Thus, Sae may be more important in the bacterial response to NETs. NETs had an overall neutral role during a 14-day infection with sub-lethal dose. However, weight fluctuations early in infection suggest that NETs may impact acute infection progression.
These results indicate that certain S. aureus toxins could synchronously respond to NETosis and that NET formation may have a variable role that depends on the bacterial load. While at sub-lethal doses, there are no specific effects of NETs, this may change at clinically relevant doses. In the future, it will be useful to test higher bacterial doses and the virulence of mutant strains to determine systems that can be targeted for developing therapeutics
Additive manufactured low carbon cementitious materials using low-value byproducts from biofuel production
Get PDFCement is the backbone of over half of all buildings in the United States, establishing its need and continual use as a construction material. However, for every one ton of cement that is produced, one ton of carbon dioxide is emitted. Therefore, a more sustainable method of cement usage must be utilized to decrease the carbon footprint of cement. Reducing the carbon dioxide emissions of cement can be achieved by supplementary cementitious materials (SCMs) and additive manufacturing. The focus of this work is to combine these two processes into one joint effort through additive manufacturing of a bio-derived fly ash as an SCM.
A Delta WASP 2040 Clay 3D printer was redesigned and modified to produce high-quality prints of cement mortar structures in the shape of a hollow cylinder. Cement mortar mix designs for 3D prints were optimized for printing performance with 10 wt.% of bio-based fly ash. Various properties of both the printing system and the mixture design were varied to create an ideal printing environment, mortar mixture, and resulting printed structure. Results were evaluated based on the extrusion pressure, number of layers printed, and percentage errors of total height, average layer height, and average layer thickness. A 10 wt.% bio-fly ash cement mortar was extruded and had an overall height of 40.4mm (0.88% error from projection), an average layer height of 5.05mm (1.03% error from projection), and an average layer width of 14.5mm (10.8% error from projection). With a nozzle diameter of 7mm and 100g of bio ash, the optimum water to cement ratio of 0.38 and the superplasticizer to cement ratio of 0.358 was determined.
Using bio-ash to replace 10 wt.% of construction cement would remove over 220 lbs. of GHG emissions per ton of cement. Further, material and labor cost would drop by upwards of 65% if cement structures were 3D printed. This paper demonstrates the importance of 3D printing cement mortar with bio-based, low carbon materials that reduce the overall usage of cement, directly reducing the greenhouse gas emissions of the material
RESPIRATORY VIRAL GENOMIC EVOLUTION: IMPACT ON DISEASE OUTCOMES AND IMMUNE RESPONSES
Get PDFRespiratory viruses, including Influenza A and B (IAV/IBV) viruses as well as Respiratory Syncytial Virus (RSV), cause significant health and economic burdens globally each year, especially in children. These viruses can be classified into distinct genetic populations that can co-circulate the season. Dominant subtypes/genotypes circulating geographically, demonstrating that local surveillance efforts are important. Local genomic surveillance is critical for understanding circulation patterns, detecting genomic changes, and corresponding changes to disease severity.
In this study, genomic surveillance, and evolution for IAV, IBV and RSV at the Johns Hopkins Hospital System during the 2023-2024 season was described. During this study period, 52,343 respiratory samples were collected, 5.1% were IAV positive, 1.4% were IBV positive and 4.6% were RSV positive. Leftover patient samples (587 influenza and 417 RSV) were randomly selected for amplicon based next generation sequencing using Oxford Nanopore Technologies. Phylogenetic analyses were performed on IAV/IBV hemagglutinin (HA) and neuraminidase (NA) genes and RSV glycoprotein and fusion-protein genes and any prominent amino acid substitutions (AAS) or those thought to have impacts of antigenicity or available vaccines and treatments were described. Phylogenetic trees were generated to visualize genetic diversity within these viruses.
The 2023-2024 influenza season saw a shift in dominance from H3N2 (16.7%), in previous seasons to H1N1pmd09 (71.7%). IBV (11.6), Victoria lineage, was also determined to be circulating. Increased hospital admission was associated with H1N1pdm09 predominance. Several AAS detected in the HA and NA genes may impact antigenicity and susceptibility to
therapeutics. Phylogenetic analysis showed heterogenous circulation of HA and NA segments in H1N1pdm09 and IBV viruses. The RSV 2023-2024 season was predominantly RSV-B (79.6%) than RSV-A (20.4%). No differences in clinical severity between the two genotypes were observed. Multiple AAS that were thought to impact antigenicity and susceptibility to
therapeutics. Phylogenetic analysis showed that the RSV populations circulating were genetically diverse and may represent distinct lineage introductions into the Baltimore area.
With the approval of the new RSV vaccine and continued use of seasonal influenza vaccines, local genomic surveillance efforts are critical for the understanding of respiratory virus circulation and genomic evolution
Inferring Transmission Pathways from Incomplete Data: Applications to Contact Network Structure and Household Data
Get PDFEstimates of epidemiological parameters relevant to pathogen transmission are important inputs to informed pathogen control strategies. However the underlying infection process is rarely fully observed, limiting our ability to make accurate inferences about transmission processes. This dissertation presents a variety of methods developed to make inferences about transmission pathways in a variety of settings from incomplete data.
Contact behavior is a key driver of transmission of respiratory pathogens throughout populations. We utilize longitudinal contact survey data to estimate drivers of differences in first and second-order contact network structure in Southern China. We find that among both older individuals and those in less dense areas the number of contacts made per day is reduced and the local clustering of those contacts is increased. More intimate contacts are also associated with higher levels of clustering.
Household data is another rich source of information for estimation of transmission parameters. Traditional methods for the analysis of household data depend on assumptions of complete observation which are often not met. We developed a hidden Markov model which is flexible to a variety of observation and transmission processes and applied this model to household transmission of SARS-CoV-2 in Baltimore, Maryland and cholera in Bangladesh.
We find that the model is able to recover simulated parameter values with reasonable accuracy and when applied to longitudinal household data it captures variation in extra-household SARS-CoV-2 infection risk over time. We identify several factors associated with increase extra-household infection risk in Baltimore including young and old age and black race.
Finally, we adapt the model to a household study of cholera with multiple layers of observation. We find no significant difference in intra-household infection risk by symptom status and high extra-household infection risk which extends beyond the infectious period, likely due to shared household exposures.
The ability to make valid epidemiological inferences from limited data is a critical component of timely and effective response to pathogen spread. The methods presented here may help equip public health practitioners with the information needed to respond to outbreaks in an informed manner and therefore better mitigate the burden of infectious diseases
Lévy Distributed Fluctuations and Cytoquakes in the Actomyosin Cortex
No full textThe actomyosin cortex is an active material that provides animal cells with a strong but flexible exterior, whose mechanics, including non-Gaussian fluctuations and occasional large displacements or cytoquakes, have defied explanation. I studied the active nanoscale fluctuations of the cortex using high-performance tracking of an array of flexible microposts adhered to multiple cultured cell types. When the confounding effects of static heterogeneity and tracking error are removed, I found the fluctuations to be heavy-tailed and well-described by a truncated Lévy stable distribution over a wide range of timescales and multiple cell types. Notably, cytoquakes appear to correspond to the largest random displacements, unifying all cortical fluctuations into a single spectrum. These findings reinforce the cortex's previously noted similarity to soft glassy materials such as foams, and the form of the fluctuation distribution constrains future models of the cytoskeleton
OPTICAL COHERENCE TOMOGRAPHY BASED OPHTHALMIC AND GASTROINTESTINAL SURGICAL GUIDANCE USING DEEP LEARNING
Get PDFBlindness from corneal diseases is a global public health issue and Deep anterior lamellar keratoplasty (DALK) is one of the main curative treatments [1]. It is a challenging step and requires micron accuracy to guide the needle to the Descemet’s Membrane (DM). Small bowel ischemia is another type of life-threatening medical conditions, and therefore, timely intestinal resection and anastomosis are essential for re-establishing the intestinal blood flow [2]. Our group has been developing a supervised autonomous robotic system (STAR) to conduct the laparoscopic intestinal anastomosis. It is crucial for the real-time automatic tissue sensing and intraoperative evaluation of bowel perfusion to improve the autonomy of the system. In this thesis, the main hypothesis is that optical coherence tomography (OCT) has the potential to guide the robotic system for ophthalmic and gastrointestinal surgeries.
To extract the optical properties of tissue from OCT images, a robust and accurate computation model was developed for parametric imaging and related diagnostic applications. The estimated attenuation coefficient and backscattering fraction with the attenuation compensation model can provide an improved resolution over the entire OCT imaging range. Furthermore, the OCT integrated robotic system was evaluated on rabbit and porcine corneas for the DALK procedure, which resulted in fewer perforations of DM and deeper pneumodissection of stromal tissue.
For the gastrointestinal surgery application, a multimodal optical imaging based quantitative vision platform was designed and implemented for analyzing the intestinal perfusion level. The conditional generative adversarial network (cGAN) was utilized for perform dual-modality image alignment and translation during the swine model study. Moreover, by integrating the fiber probe with STAR system, OCT guided suturing procedure was proposed by identifying eight different abdominal tissue types to avoid missed or wrong stitches for intestinal anastomosis