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Title: Adaptive Learning Approach of a Domain-Aware CNN-Based Model Observer
Creator: Bogdanovic, Nebojsa
Date: 2023
Description: Application of convolutional neural networks (CNNs) for performing defect detection tasks and their use as model observers (MO) has become...
Show moreApplication of convolutional neural networks (CNNs) for performing defect detection tasks and their use as model observers (MO) has become increasingly popular in the medical imaging field. Building upon this use of CNN MOs, we have trained the CNNs to discern between the data it was trained on, and the previously unseen images. We termed this ability domain awareness. To achieve domain awareness, we are simultaneously training a new variation of U-Net CNN to perform defect detection task, as well as to reconstruct a noisy input image. We have shown that the values of the reconstruction mean squared error can be used as a good indicator of how well the algorithm performs in the defect localization task, making a big step towards developing a domain aware CNN MO. Additionally, we have proposed an adaptive learning approach for training these algorithms, and compared them to the non-adaptive learning approach. The main results that we achieved were for the ideal observers, but we also extended these results to human observer data. We have compared different architectures of CNNs with different numbers and sizes of layers, as well as introduced data augmentation to further improve upon our results. Finally, our results show that the proposed adaptive learning approach with introduced data augmentation drastically improves upon the results of a non-adaptive approach in both human and ideal observer cases.
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Title: Evaluating antimicrobial efficacy of GS-2 on reusable food packaging materials
Creator: Birje, Nupoor Prasad
Date: 2024
Description: Packaging plays an important role in maintaining the quality and safety of fresh produce throughout storage, transportation and end-use by...
Show morePackaging plays an important role in maintaining the quality and safety of fresh produce throughout storage, transportation and end-use by consumers. Single-use packaging poses several environmental impacts; therefore use of reusable packaging is being encouraged in the fresh produce supply chain. However, the utilization of harmful chemicals and inadequate sanitation standards limit the reuse of packaging materials. To overcome these limitations, this study focuses on testing a non-toxic, water-soluble antimicrobial; GS-2 coating to facilitate the reuse of food packaging and reduce the risk of microbial contamination. In this study, the antimicrobial activity of GS-2 was evaluated against foodborne pathogens; Escherichia coli, Listeria monocytogenes and Salmonella enterica on plastic and cardboard coupons at 1 h and 15 min treatment times and 0.3%, 1% and 3% concentration. These coupons were also stored at 4℃ and 90% R.H. and 18℃ and 45% R.H. inoculated on different days up to 42 d with E. coli or L. monocytogenes to study retention of activity of GS-2. Additionally, the efficacy of GS-2 to reduce transfer of bacteria from cardboard and plastic to tomato was investigated. The initial level of inoculum was 9 log CFU/surface for all experiments. Cardboard and plastic without GS-2 were used to compare the reduction of bacteria on the treated surfaces. The differences in the population of bacteria were evaluated using Student’s T-Test and ANOVA; p <0.05 was considered significant. With 3% GS-2 concentration on plastic, there was > 4.50 log CFU/surface reduction of all three bacteria in 1 h. There was a lower reduction of the population on cardboard as compared to plastic for all bacteria, the reduction obtained was 1.83, 2.65 and 3.42 log CFU/surface for E. coli, L. monocytogenes and S. enterica, respectively, in 1 h. There was no significant difference between 15 min and 1 h treatments for cardboard. Further, the highest reduction of bacteria was obtained with 3% GS-2 on plastic. For cardboard, no significant difference in population reduction was obtained for E. coli or S. enterica, with 1% or 3% GS-2. However, for L. monocytogenes there was a higher reduction with 3%. GS-2 remained active on the surface of plastic and cardboard for a period of six weeks. For cardboard, there was a lower reduction of bacteria and there was no trend in the population reduction from 0 to 42 d, with the populations remaining within a range of 4-5 log CFU/surface. There was a significant transfer of E. coli or L. monocytogenes from plastic surfaces without GS-2 to tomato at 5-6 log CFU/tomato. However, the transfer of bacteria from the GS-2-coated plastic to the tomato was below the limit of enumeration. For cardboard, the population was below the limit of enumeration, irrespective of the GS-2 coating. Based on the results, GS-2 is a promising antimicrobial that reduces the microbial load on packaging surfaces and prevents cross-contamination of fresh produce. The retention of GS-2 activity makes it suitable for reusable packaging applications.
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Title: Examination of Listeria monocytogenes survival in refrigerated chopped hard-boiled eggs and deli salads containing this ingredient
Creator: Marathe, Aishwarya Nagesh
Date: 2024
Description: Peeled hard-boiled eggs (HBEs) are widely favored by both consumers and food services due to their convenience. These HBEs are often chopped...
Show morePeeled hard-boiled eggs (HBEs) are widely favored by both consumers and food services due to their convenience. These HBEs are often chopped and incorporated into various dishes such as deli salads. However, recent recalls of hard-boiled eggs have brought attention to the risk of contamination with Listeria monocytogenes. Prepared HBEs are typically subjected to antibacterial treatment to maintain product safety and quality. Citric acid is a common antibacterial used in the food industry to treat the HBEs. Previous research has determined that 2% citric acid treatment is effective against L. monocytogenes on whole HBEs. This study examined the efficacy of citric acid on the reduction of L. monocytogenes on chopped HBEs and in deli salads containing chopped HBEs. HBEs were treated with 2% citric acid or water (untreated) by submersion for 24 h at 5°C. HBEs were dried for 10 min, inoculated with a 4-strain cocktail of rifampicin-resistant L. monocytogenes, at 1 (low-level inoculation) or 4 log CFU/HBE (high level-inoculation), and allowed to dry for 10 min. Low-level inoculated HBEs were chopped and stored at 5, 10, or 15°C for 28 d. High-level inoculated HBEs were chopped and stored at 5, 10, and 25°C for 14 d. Low-level inoculated HBEs were also chopped and incorporated into potato, tuna, chicken, or macaroni salad at a 1:6 ratio (HBE to other ingredients), or into egg salad at a 7:1 ratio. Salads were stored at 5, 10, or 15°C for 28 d. The presence of L. monocytogenes was determined at intervals during storage by enrichment with BLEB and/or enumerated on BHIArif throughout storage. Triplicate samples were assessed for each time point, and three independent trials were conducted. Data was analyzed by Student’s T-test, ANOVA, and Fisher’s exact test, p≤0.05. For low-level inoculated chopped HBEs, the L. monocytogenes population was significantly higher in untreated chopped HBEs (1.86±0.33 log CFU/g) as compared to treated chopped HBEs (1.47±0.27 log CFU/g) on day 14 at 15°C. On both untreated and treated chopped HBEs, there was no significant difference in the population of L. monocytogenes up to 7 d. However, from 14 d, there was a significant increase in the growth of L. monocytogenes (1.86±0.33 to 2.18±0.35 log CFU/g on untreated chopped HBEs and 1.47±0.27 to 1.94±0.47 log CFU/g for treated, respectively). For high-level inoculated HBEs, a higher L. monocytogenes growth rate was observed on untreated chopped HBEs as compared to treated chopped HBEs at 10 and 25°C. It was observed that treated chopped HBEs at 5°C took the longest to reach 1 log CFU/g increase in the L. monocytogenes population (50 d) whereas, untreated chopped HBEs at 25°C took the shortest (0.22 d). Untreated chopped HBEs showed a significantly higher population of L. monocytogenes as compared to treated chopped HBEs on 14 d at all storage temperatures. In deli salads containing chopped HBEs, potato salad showed the highest growth of L. monocytogenes after 14 d, followed by macaroni, egg, chicken, and tuna salad. The population of L. monocytogenes was the lowest in tuna salad. L. monocytogenes was present throughout the storage period at all storage temperatures. It was observed that 2% citric acid is more efficient in controlling the growth of L. monocytogenes in chopped HBEs as compared to when those HBEs are incorporated into deli salads. The findings contribute to the formulation of preventive measures and standards aimed at guaranteeing the safety of HBEs.
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Title: Resolvent Analysis of Turbulent Flow over Compliant Surfaces: Optimization Methods and Stability Considerations.
Creator: Lapanderie, Kilian Pierre Lucien
Date: 2024
Description: This thesis delves into the manipulation of turbulence properties through innovative compliant surface designs. Turbulence, known for its...
Show moreThis thesis delves into the manipulation of turbulence properties through innovative compliant surface designs. Turbulence, known for its unpredictable fluid movements, presents substantial challenges across engineering disciplines, particularly in optimizing system efficiency and minimizing energy losses. This research explores the potential of compliant surfaces to control and mitigate the adverse effects of turbulent flow, thereby enhancing the performance and reliability of engineering systems.Employing the resolvent analysis method, this work investigates the interaction between turbulent flows and surfaces capable of dynamic adaptation. The study evaluates the impact of these surfaces on turbulence suppression through the application of both space-dependent and independent compliance models, where the compliance model is characterised by an admittance, which represents the relationship between the instantaneous surface pressure and surface velocity. This approach allows for a nuanced understanding of how different surface properties can influence the behavior of turbulent flows.A significant contribution of this thesis is the comprehensive stability analysis conducted to assess the implications of compliant surfaces on the linear stability of the dynamical system. By examining the eigenvalues of the mean-linearized system, the research identifies the conditions under which compliant surfaces may induce or mitigate instabilities within turbulent flows. This analysis is pivotal in developing compliant surface designs that not only reduce turbulence-induced energy losses but also ensure the stability of the flow, a critical consideration for practical engineering applications.The findings of this thesis offer valuable insights into the role of surface compliance in turbulence control, paving the way for further research and the development of advanced engineering solutions. Through a detailed investigation of the interactions between compliant surfaces and turbulent flows, this work contributes to the broader field of fluid dynamics and underscores the potential of innovative surface designs in achieving more efficient and sustainable engineering systems.
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Title: Measurement and Control of Beam Energy at the Fermilab 400 MeV Transfer Line
Creator: Mwaniki, Matilda W.
Date: 2023
Description: Linac is the first machine in the Accelerator chain at Fermilab where particles are accelerated from 35 keV to 400 MeV and travel to the...
Show moreLinac is the first machine in the Accelerator chain at Fermilab where particles are accelerated from 35 keV to 400 MeV and travel to the Booster where they are stripped of the extra electrons to become protons. Tuning Linac is performed using diagnostics to ensure stable intensity and energy while minimizing uncontrolled particle loss. I have been revisiting diagnostics in the Linac in order to understand their signals and to ensure their data is reliable. I revisited Beam Loss Monitors (BLMs) for the loss data confidence. For the confidence of energy data there were two approaches. The first approach was time-of-flight measurements using Beam Position Monitors (BPMs) and beam velocity stripline pick-up that provides beam phase data. The second approach used the relation between beam position data from BPMs and dispersion values from MAD-X simulation to calculate energy. Our goal after understanding the data from the Linac diagnostics and finding the data reliable is to control the Linac parameters using Machine Learning techniques to increase the reliability and quality of beam delivered from Linac.
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Title: Utility of a Low-Coverage Genome Assembly for Discovery of Genes Associated with Pyrethroid Resistance in Smicronyx Fulvus LeConte
Creator: Markiv, Paulina Patrycja
Date: 2023
Description: Red sunflower seed weevil (RSSW) is a major insect pest of cultivated and wild common sunflowers in the Great Plains of North America. The...
Show moreRed sunflower seed weevil (RSSW) is a major insect pest of cultivated and wild common sunflowers in the Great Plains of North America. The extent of the sunflower damage due to RSSW infestation is too great for the natural sunflower defense mechanisms to protect the agriculture industry from losses. Pyrethroids are the only type of insecticide designated for the control of RSSW; however, instances of pyrethroid insecticide ineffectiveness against RSSW have been annually reported to entomologists at South Dakota State University since 2017. The biological bases of insecticide resistance are unknown but common mechanisms associated with pyrethroid resistance include general detoxification mechanism driven by cytochrome P450s (CYP450s) as well as mutations in the pyrethroid target, voltage-gated sodium channels (VGSCs). The goal of this study was to determine if the computational analysis of a low-coverage genome assembly is sufficient to identify and characterize genes associated with insecticide resistance which could contribute to pest control research efforts. By using a low-coverage genome assembly, RNA-Seq data, and bioinformatic tools, 40 complete and 33 partial gene models coding for CYP450 as well as a partial gene model coding for VGSC have been identified in the genome of RSSW. Twenty-seven mutation sites, previously associated with the pyrethroid resistance in other insects, have been identified in the VGSC gene of RSSW. The low-coverage genome proved to be a sufficient resource for preliminary studies of gene identification which could bring significant knowledge to subsequent research focusing on insecticide resistance and pest control.
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Title: Voxel Transformer with Density-Aware Deformable Attention for 3D Object Detection
Creator: Kim, Taeho
Date: 2023
Description: The Voxel Transformer (VoTr) is a prominent model in the field of 3D object detection, employing a transformer-based architecture to...
Show moreThe Voxel Transformer (VoTr) is a prominent model in the field of 3D object detection, employing a transformer-based architecture to comprehend long-range voxel relationships through self-attention. However, despite its expanded receptive field, VoTr’s flexibility is constrained by its predefined receptive field. In this paper, we present a Voxel Transformer with Density-Aware Deformable Attention (VoTr-DADA), a novel approach to 3D object detection. VoTr-DADA leverages density-guided deformable attention for a more adaptable receptive field. It efficiently identifies key areas in the input using density features, combining the strengths of both VoTr and Deformable Attention. We introduce the Density-Aware Deformable Attention (DADA) module, which is specifically designed to focus on these crucial areas while adaptively extracting more informative features. Experimental results on the KITTI dataset and the Waymo Open dataset show that our proposed method outperforms the baseline VoTr model in 3D object detection while maintaining a fast inference speed.
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Title: Ultrasound Image Guided Robot Arm for Targeted Delivery of Therapeutic Drugs and MicroRNA for Cancer Therapy
Creator: Nagarajan Parimala, Abishek
Date: 2024
Description: Molecular imaging has revolutionized medical diagnostics by providing detailed insights into biological processes at the molecular level...
Show moreMolecular imaging has revolutionized medical diagnostics by providing detailed insights into biological processes at the molecular level within the living subject. Ultrasound Molecular Imaging (USMI) has emerged as a promising diagnostic imaging modality by utilizing targeted contrast agents to unveil crucial molecular information, including vascular biomarkers associated with cancer and other diseases. Despite its potential, the transition of Ultrasound Contrast Agents (UCA) from preclinical evaluation to FDA-approved clinical use faces challenges due to the short in vivo half-life of Micro-Bubbles (MBs), necessitating repeated administrations for comprehensive assessments. Moreover, conventional ultrasound imaging methods suffer from limited scanning areas and single-target focus, leading to low throughput in preclinical evaluations.This thesis addresses these challenges by proposing a robot-assisted whole-body scanning pipeline for preclinical evaluations in Ultrasound Molecular Imaging. By integrating a robotic arm into the imaging setup, this approach enhances scanning flexibility and precision, enabling scans across the entire body of a mouse. This extension of the imaging time window allows for comprehensive assessments without the need for repeated contrast agent administrations. Additionally, the ability to simultaneously scan multiple targets within the same session significantly increases the throughput of preclinical assessments, thereby improving the efficiency and reliability of Ultrasound Molecular Imaging in clinical translation.
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Title: Sex and Architecture
Creator: Nekkanti, Hashika C.
Date: 2023
Description: This thesis delves into the fascinating and intricate connection between sexual behaviour and architecture, offering a comprehensive...
Show moreThis thesis delves into the fascinating and intricate connection between sexual behaviour and architecture, offering a comprehensive exploration of the multifaceted factors that shape human sexuality within the context of built environments. The research is divided into six chapters, each providing a distinct perspective on the complex relationship between sexuality and the spaces we inhabit. Chapter 1 serves as an introduction, setting the stage for the study and highlighting the importance of understanding how architectural design and spatial arrangements can influence and be influenced by human sexual behaviours. Chapter 2, "Milieu and Sexed Bodies," delves into the impact of environmental stimuli on sexual arousal. By examining how architectural elements, aesthetics, and spatial configurations can elicit eroticism and arousal, this chapter sheds light on the subtle ways in which built environments interact with our intimate desires. Furthermore, it delves into the psychological aspects of fetishism and voyeurism, exploring how these sexual behaviours find expression within architectural settings. Chapter 3, titled "Sexual Behaviour," delves into the profound influence of history on human sexuality. It examines how cultural norms, religious beliefs, and social backgrounds have shaped and continue to shape sexual attitudes and behaviours across different societies and time periods. The chapter also explores the concept of polymorphous behaviour, emphasizing how architecture can create spaces that cater to diverse expressions of human sexuality. Additionally, it investigates the impact of queer spaces, highlighting the significance of inclusive design in fostering a sense of belonging and acceptance for individuals with diverse sexual identities. Chapter 4 turns its attention to "Mediated Sexuality," offering a historical analysis of how various forms of media have played a pivotal role in shaping sexual attitudes and behaviours. From ancient art to contemporary pornography, this chapter explores how media representations have influenced perceptions of sexuality, and it examines the emergence of pornomodernism, a cultural phenomenon impacting both media and architectural expressions of eroticism. Moreover, it investigates how architecture has incorporated and responded to the eroticized spaces depicted in media. Chapter 5 focuses on the "Coital Environment," a fascinating aspect of architecture that intertwines with sexual behaviour. This chapter delves into the realm of sex tourism, examining how certain destinations and spaces have become associated with sexual encounters. It analyses the design and function of dedicated places for sex within architectural contexts, providing insights into the factors that influence the creation and acceptance of such spaces in different societies. Finally, Chapter 6 presents a comprehensive "Conclusion," synthesizing the key findings from the preceding chapters. It emphasizes the critical role that architecture plays in shaping human sexual behaviours and highlights the social and cultural implications of design decisions in built environments. The chapter concludes with reflections on the significance of creating inclusive and supportive spaces that celebrate and embrace diverse sexual identities and experiences, paving the way for more empathetic and human-centric architectural design in the future. In conclusion, this thesis offers a profound exploration of sexual behaviour and architecture, shedding light on the intricate interplay of environmental stimuli, historical influences, and mediated sexuality in shaping our intimate experiences within the spaces we inhabit. It serves as a valuable resource for architects, urban planners, social scientists, and anyone interested in creating environments that foster a positive and inclusive approach to human sexuality.
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Title: IMPACT OF DATA SHAPE, FIDELITY, AND INTER-OBSERVER REPRODUCIBILITY ON CARDIAC MAGNETIC RESONANCE IMAGE PIPELINES
Creator: Obioma, Blessing Ngozi
Date: 2020
Description: Artificial Intelligence (AI) holds a great promise in the healthcare. It provides a variety of advantages with its application in clinical...
Show moreArtificial Intelligence (AI) holds a great promise in the healthcare. It provides a variety of advantages with its application in clinical diagnosis, disease prediction, and treatment, with such interests intensifying in the medical image field. AI can automate various cumbersome data processing techniques in medical imaging such as segmentation of left ventricular chambers and image-based classification of diseases. However, full clinical implementation and adaptation of emerging AI-based tools face challenges due to the inherently opaque nature of such AI algorithms based on Deep Neural Networks (DNN), for which computer-trained bias is not only difficult to detect by physician users but is also difficult to safely design in software development. In this work, we examine AI application in Cardiac Magnetic Resonance (CMR) using an automated image classification task, and thereby propose an AI quality control framework design that differentially evaluates the black-box DNN via carefully prepared input data with shape and fidelity variations to probe system responses to these variations. Two variants of the Visual Geometric Graphics with 19 neural layers (VGG19) was used for classification, with a total of 60,000 CMR images. Findings from this work provides insights on the importance of quality training data preparation and demonstrates the importance of data shape variability. It also provides gateway for computation performance optimization in training and validation time.
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Title: LOW-COVERAGE GENOMES AS AN EFFECTIVE AND ECONOMICAL APPROACH FOR LEPIDOPTERAN MICROSATELLITE ISOLATION
Creator: Liang, Huijia
Date: 2020
Description: This study aimed to verify that whether a low-coverage genome can work as an effective approach to isolate Lepidopteran microsatellites. As...
Show moreThis study aimed to verify that whether a low-coverage genome can work as an effective approach to isolate Lepidopteran microsatellites. As microsatellites are useful tool to study population genetics, and there are many Lepidopteran agriculture pests which can cause huge economic damages every year, additionally, Lepidoptera have abundant similar flanking sequences making it difficult to develop reliable microsatellites. However, there are not enough published genomes of Lepidoptera species. If low-coverage Lepidopteran genomes can be used to isolate reliable microsatellites, the low-coverage genomes would be an effective and economical approach for microsatellites isolation, because low-coverage genome sequencing is much cheaper and less time-consuming than the published genome sequencing.
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Title: Associations between subjective cognitive decline, neurodegeneration, and vascular neuroimaging markers: Findings from a multiethnic cohort
Creator: Gonzalez, Christopher
Date: 2023
Description: Mounting evidence suggests that subjective cognitive decline (SCD) may provide a unique target to identify the earliest changes in cognitive...
Show moreMounting evidence suggests that subjective cognitive decline (SCD) may provide a unique target to identify the earliest changes in cognitive function in Alzheimer’s disease (AD). In addition, vascular-related risk factors are also linked to increase the risk of clinical expression of AD, and independently increase the risk for vascular dementia (VaD). However, most investigations have not explored SCD across a multiethnic population. The study investigated 1) the associations between white matter hyperintensities (WMH) and targeted neuroimaging AD markers (hippocampal volume, cortical thickness of AD regions) with SCD amongst a multiethnic cohort, and 2) whether race moderated the relationship between them. A total of 871 older adults ages from 62-96 years old with a mean age of 74.48 (SD = 6.11), mean education of 12.79 years (SD = 4.53), and with 62% identifying as female were recruited from preexisting data from the Washington Heights Inwood Columbia Aging Project (WHICAP). Linear regression model revealed a significant association between WMH and both AD targeted neuroimaging markers across the total sample. Secondary analyses revealed that race did not moderate the relationship between WMH and AD cortical thickness with SCD but did in fact moderate the relationship between hippocampal volume and SCD. Results suggest that cultural biological differences exist in the Hispanic/Latine individuals compared to non-Hispanic White and non-Hispanic Black individuals.
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Title: Evaluation of the Native Microbiota and Comparative Analysis of a Known Cronobacter Sakazakii and a Newly Isolated Bacillus Cereus Strain in Powdered Infant Formula
Creator: Patil, Sonali Prashant
Date: 2024
Description: There have been numerous reports of Powdered Infant Formula (PIF) recalls and outbreaks due to the absence of a kill step in the post...
Show moreThere have been numerous reports of Powdered Infant Formula (PIF) recalls and outbreaks due to the absence of a kill step in the post-pasteurization processing, improper handling pre and post processing and/or reconstitution, and lack of effective sanitization and cleaning of the food contact surfaces in the manufacturing facilities. The objectives of this present study were to 1) survey and identify background microflora in commercial PIF products through microbiological analysis, 16S rRNA, and whole genome sequencing (WGS); 2) compare the survival rate of a known Cronobacter sakazakii and a newly isolated Bacillus cereus DFPST-SP1 in PIF under a humidity level of 33 ± 3% over a period of 28 d; 3) examine the relative resistance of these two strains to thermal treatments at temperatures 40, 70, and 100 °C followed by storage at room temperature (RT) for 30 min; and 4) evaluate the bactericidal effect of 70% ethanol on the two artificially deposited bacterial strains on stainless steel (SS) and plastic coupons. Three biological trials were conducted for each study. To determine whether the increase, decrease, or difference in the bacterial populations and other parameters like water activity (aw) was statistically significant, a T-test was performed (p ≤ 0.05 was considered significant). Results of 16S rRNA sequencing revealed the presence of certain bacterial species in PIF, such as Lactococcus lactis, B. cereus, Listeria monocytogenes, Staphylococcus aureus, Salmonella enterica, etc. distributed across a relative abundance of >25%, <25%, and ≤3%. After the enrichment and isolation as per Bacteriological Analytical Manual (BAM), C. sakazakii or S. enterica were not detected, while colonies exhibiting a blue-green appearance resembling Listeria spp. and certain Bacillus spp. were subjected to WGS for species-level identification. The assembly_1 from formulation 1 was confirmed as B. cereus sequence type 2255 and was renamed as B. cereus DFPST-SP1 in the contribution of this thesis work. The storage study conducted on PIF inoculated with C. sakazakii and B. cereus DFPST-SP1 at 33% RH showed that there was 0.25-0.27 log CFU/g reduction towards the end of 28 d, but no significant difference was observed between the two strains. The thermal challenge study revealed that the newly isolated B. cereus strain and C. sakazakii used in this study were highly thermotolerant. Based on the sanitizer challenge study, 70% ethanol was significantly more effective in reducing populations of C. sakazakii as compared to B. cereus. Moreover, higher log reductions of C. sakazakii 587 populations on stainless steel coupons compared to plastic coupons were observed, indicating that bacteria adhere more tightly to plastic surfaces than stainless steel (SS). Overall, the findings of this study shed new light on bolstering the safety standards of PIF and highlight the need for improved cleaning and sanitization procedures within manufacturing facilities in order to ensure the safety of reconstituted PIF, thereby enhancing public health, particularly infants and neonates.
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Title: Students International House
Creator: Peterhans, Brigitte 1928-2021
Date: 1961

Title: Cardiolipin Modulates the Insertion of Adsorbed Helical Amyloid Beta Peptide Into Model Mitochondrial Membranes
Creator: Kaczmarek, Julia A.
Date: 2023
Description: The loss of mitochondrial phospholipid cardiolipin (CL) may play a role in both the pathogenesis of Alzheimer's Disease (AD) and its treatment...
Show moreThe loss of mitochondrial phospholipid cardiolipin (CL) may play a role in both the pathogenesis of Alzheimer's Disease (AD) and its treatment. An effector molecule of the disease, amyloid-beta (Aβ), has been observed to interact with lipid membranes, but its relevance to mitochondrial membranes containing CL remained elusive. The present study investigated if the presence of CL modulated the insertion of adsorbed helical amyloid beta (Aβ14-40) into model mitochondrial membranes, and if this effect was more pronounced for its N-terminus or C-terminus. I conducted a coarse-grained computer simulation using well-tempered metadynamics to traverse the free energy landscape that maps the translocation of Aβ14-40. Insertion into CL-containing bilayers created larger local membrane deformations and modulated the location of the transition path but had an inconclusive impact on the free energy cost of translocation. Since the generation of toxic calcium-permeable pores depends on the insertion of Aβ into the bilayer, the loss of CL seen in AD may prime the inner mitochondrial membrane for pore formation, but more research is needed to pursue this hypothesis.
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Title: Evaluation of the efficacy of power ultrasound technology coupled with organic acids to reduce listeria monocytogenes on peaches and apples
Creator: Joshi, Mayura Anand
Date: 2024
Description: Fresh fruits and vegetables are prone to microbial contamination throughout different phases of human handling, processing, transportation,...
Show moreFresh fruits and vegetables are prone to microbial contamination throughout different phases of human handling, processing, transportation, and distribution. Emerging technologies, such as power ultrasound, have received attention due to their capacity to reduce or eliminate foodborne bacterial pathogens on these commodities. Power ultrasound, when combined with certain antimicrobials, has demonstrated its effectiveness as a valuable tool for washing fresh produce. The objective of this study was to examine the effectiveness of power ultrasound combined with organic acids on the reduction of Listeria monocytogenes on fruits. In this study, peaches and apples were subjected to surface inoculation with a four-strain cocktail of L. monocytogenes and dried for 1 h. Stomacher bags, containing 225 mL of citric, lactic, or malic acids at concentrations of 1%, 2%, or 5%, were employed for treating inoculated peaches and apples. The acid treatment was used alone, or in combination with power ultrasound for 2, 5, or 10 min. Water was used for controls. Before treatment, the initial population of L. monocytogenes on apples was lower compared to the initial population on peaches, with apples showing a 1.94 log CFU/fruit reduction. Water controls demonstrated no significant log reduction in both apples and peaches. The greatest L. monocytogenes reduction on apples occurred when treated with 1% citric acid for 2 min with power ultrasound where L. monocytogenes was significantly reduced from 6.98±0.88 log CFU/fruit to 5.56±0.91 log CFU/fruit. The greatest L. monocytogenes reduction on peaches occurred when treated with 5% citric acid for 5 min with power ultrasound where L. monocytogenes was significantly reduced from 7.44±0.45 log CFU/fruit to 6.68±0.40 log CFU/fruit. Overall, the combined effect of acid and power ultrasound was more pronounced in apples than in peaches. The survival of L. monocytogenes on apples and peaches appeared to be highly dependent on the specific treatment and hurdle technology applied. The combination of ultrasound hurdle technology with acid washing has proven effective in reducing L. monocytogenes on both peaches and apples, with a more significant impact observed on apples. While acid washing is a more economical option compared to ultrasound technology, the efficiency of microorganism reduction is considerably enhanced when power ultrasound is combined with organic acids. Looking ahead, the development of cost-effective power ultrasound methods could facilitate widespread adoption of ultrasound hurdle technology in the produce industry.
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