Biology

Permanent URI for this collectionhttps://hdl.handle.net/10315/27613

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Access status: Open Access ,
Proteomic Study Of The Ubiquitin E3 Ligase HUWE1 Interaction With Ubiquitin And ADP-Ribose Modified Proteins
(2025-07-23) Nader, Nour; Sheng, Yi
Ubiquitination and ADP-ribosylation are important post-translational modifications (PTMs), especially in cellular response to DNA damage. HECT, UBA, and WWE domain containing E3 ubiquitin protein ligase 1 (HUWE1) is an important ubiquitin E3 ligase involved in many cellular processes. HUWE1 contains regions involved in substrate interaction and domains for PTM recognition. Specifically, HUWE1 WWE and tandem ubiquitin-binding motif (tUBM) domains interact with ADPr/iso-ADPr and ubiquitin, respectively. However, the interaction between these domains and cellular ADP-ribose and ubiquitin and potentially substrate interactions are not well investigated. Thus, this project aimed to investigate the interactome of HUWE1 WWE and tUBM domain, focusing on their ability to bind proteins modified by mono-ADP-ribose (MAR)/poly-ADP-ribose (PAR) and ubiquitin using GST pulldown assay. First, using Western blot and confocal microscopy, distinct dynamics of ubiquitination and ADP-ribosylation were observed in response to different DNA damage treatments. Second, the study demonstrated that the WWE-tUBM domain interacts with both cellular ADP-ribose and ubiquitin. Moreover, through a proteomic approach using affinity mass spectrometry, this study identified novel proteins that interact with the WWE and tUBM domains following Ultraviolet (UV) induced DNA damage. Together, the findings of this project contribute to a better understanding of how HUWE1 engages with its substrates and highlight the role of WWE and tUBM domains and their ability to recognize PTMs in mediating these interactions.
Access status: Open Access ,
Genome Wide Analysis Of Admixture In Apis Mellifera Intermissa
(2025-07-23) Ritchie, Caroline Rose; Zayed, Amro
Unraveling the evolutionary history of Apis mellifera reveals how populations have adapted to diverse environments, resisted disease, and responded to human influence. An admixed population of A. m. intermissa in Morocco has sparked debate over the dispersal routes of A. mellifera and the origin of the European (M) lineage. Yet, despite its identification, the genomic consequences of this admixture remain largely unexplored. We analyzed global and local ancestry, estimated admixture timing, and assessed genetic diversity in this A. m. intermissa population. Our findings reveal recent admixture, occurring ~14 generations ago, with genome-wide diversity reflecting an intermediate value between progenitor lineages. Notable regions on chromosomes 7 and 11 showed high enrichment for M lineage ancestry. Functional enrichment and prior studies suggest these regions influence detoxification, immunity, development, and hormonal regulation. Four QTLs with 18 loci further support M lineage contributions to Varroa destructor resilience. These findings reveal the functional role of M lineage ancestry in North African Apis mellifera populations and offer a framework for further exploring the genomic outcomes of admixture.
Access status: Open Access ,
Probing the Activity of Fmta, A Novel Esterase in Staphylococcus Aureus, in Vitro and in Vivo Through Mutagenesis.
(2025-07-23) Sengupta, Saptarshi; Golemi-Kotra, Dasantila
The versatile bacterium Staphylococcus aureus (S. aureus) resides within the human microbiota, manifesting commensal and pathogenic characteristics. The emergence of methicillin-resistant S. aureus (MRSA) underscores the global challenge of antibiotic resistance. FmtA, a protein exhibiting structural similarities and distinct features relative to Penicillin-binding proteins (PBPs) within the Penicillin penicillin-recognizing proteins (PRPs) umbrella, significantly contributes to the S. aureus antibiotic resistance mechanism. FmtA acts on Wall Teichoic Acid (WTA), an abundant poly-ribitol polymer in S. aureus peptidoglycan, where FmtA removes D-Alanine (D-Ala) from WTA, which is esterified post-synthesis where the D-alanylation level in WTA is an important contributor in S. aureus antibiotic resistance and physiology. Previous research addressed the structural intricacies of FmtA and based on the positioning of key amino acid residues, it was proposed that the enzyme's active site has evolved to specifically bind WTA. It was further hypothesized that FmtA has adapted to carry out D-amino esterase activity against WTA, highlighting its specialized functional evolution. In this study, I investigate the role of specific amino acid residues present in the active site of FmtA, focusing on their interactions with WTA using both in vitro and in vivo approaches. Given the overall negative charge of WTA, derived from its phosphodiester backbone, it is a target for cationic polymers like Branched Polyethyleneimine (BPEI). Previous research has shown that BPEI binding to WTA creates a steric hindrance, disrupting the function of penicillin-binding proteins (PBPs) such as PBP4 in Staphylococcus aureus and PBP2a in Staphylococcus epidermidis. This disruption impacts key bacterial physiological processes, including cell division, virulence, and peptidoglycan biosynthesis. My findings reveal that BPEI can compete with FmtA for WTA binding, though less effectively, leading to partial inhibition of FmtA's enzymatic activity. Additionally, BPEI binding affects the physiological activities of S. aureus, including biofilm formation, which is typically mediated by FmtA. These results suggest that while BPEI hinders FmtA's interaction with WTA and its subsequent enzymatic function, it does not completely block FmtA activity.
Access status: Open Access ,
Does Motion Parallax Improve Communication Efficiency in Video Chats?
(2025-07-23) Funkhouser, Ashley Jayne; Troje, Nikolaus
As video communication has become more prevalent in our day-to-day lives, it becomes evident that face-to-face communication vastly outclasses video chat in terms of peer communication. Motion parallax is a perceptual effect that arises when an observer moves relative to their surroundings, or their surroundings move relative to them, causing nearby objects in their visual field to appear to move more quickly than distant objects. This relative motion provides a depth cue that the brain can use to estimate the relative distances and orientations of the objects. Directionality is a mutual understanding of the distance and orientation of people in 3D space (Troje, 2023). Previous studies have found that motion parallax is important in determining the direction of objects (Wang & Troje, 2023). Motion parallax can help provide directionality in day-to-day life, including aiding with nonverbal cues such as pointing or turning one’s head. This study examines whether adding motion parallax to video chat with avatars can enhance communication efficiency, as indicated by performance on an instruction task. Many nonverbal cues like mutual gaze, pointing, and eye contact rely on directionality to function accurately. Video chat can create misleading cues due to the lack of motion parallax, causing misunderstandings (Troje, 2023). This study found that the use of motion parallax while video chatting did not enhance performance on a shared task between two subjects, relative to the control. Further research is required to clarify the relationship between motion parallax and communication efficiency in video chat with avatars.
Access status: Open Access ,
Exploring the Effects of Shared Home Ranges on Human-Wildlife Interactions, Parasite Overlap, and Stress Responses in Vervet Monkeys (Chlorocebus Pygerythrus) in East Africa
(2025-07-23) Upadhayay, Pooja; Schoof, Valerie
As human populations expand and encroach upon natural habitats, boundaries between human settlements and wildlife become increasingly blurred. These shared spaces influence human-wildlife interactions and elevate the risk of zoonotic disease transmission. This dissertation investigates the consequences of overlapping home ranges for human-wildlife conflict, parasite community structure, and physiological and behavioral stress responses in vervet monkeys (Chlorocebus pygerythrus). Chapter 2 compares human-wildlife conflicts (HWCs) at sites in Uganda and Kenya, analyzing how socioeconomic factors shape local responses. Respondents reported both positive and negative effects of living near a research station or conservancy, with significant variation in conflict severity and frequency. Chapter 3 examines gastrointestinal parasite communities in sympatric hosts—humans, dogs, livestock, and vervets—around Lake Nabugabo, Uganda. Findings revealed overlapping parasite taxa across species, suggesting shared transmission pathways. Chapter 4 uses a parasite removal experiment (deworming and natural reinfection) to assess how gastrointestinal parasites affect vervet monkey fecal glucocorticoid metabolites (fGC) and behaviors. Reinfection elevated fGC levels and altered behaviors, though not always in predicted ways. This interdisciplinary research integrates ecological, parasitological, and ethological approaches to understand how habitat sharing influences disease ecology and stress in wildlife. The findings underscore the complexity of human-wildlife coexistence and highlight the importance of incorporating both ecological and social dimensions into conservation and public health strategies.
Access status: Open Access ,
The Development of the Functional Dissociation of Perception and Action
(2025-07-23) Ahmad, Zoha; Freud, Erez
Humans rely on their visual system to navigate and interact with the world, utilizing two functionally distinct cortical pathways: the ventral pathway, responsible for visual perception, and the dorsal pathway, which supports visuomotor actions. While the functional dissociation between these behaviours has been extensively studied in adults, its developmental trajectory and susceptibility to neurodevelopmental conditions is not as well-understood. This dissertation investigates the dissociation between perception and action in pediatric and adult populations with atypical neurodevelopment, focusing on three experimental studies. The first study examines a pediatric patient, TC, who underwent a unilateral cortical resection impacting both the dorsal and ventral pathways. Despite intact perceptual abilities, her visuomotor behaviors were markedly impaired, highlighting differential developmental trajectories of the two pathways and the dissociation between perception and action. The second study investigates children with amblyopia, a developmental visual disorder, and finds a reduced perception-action functional dissociation compared to neurotypical controls. This suggests that atypical visual experience disrupts the functional specialization of the pathways early in life. The final study focuses on adults with Autism Spectrum Disorder (ASD) and reveals reduced perception-action dissociation in two different contextual conditions. Together, these studies provide a detailed examination of how neurodevelopmental conditions influence the emergence of perceptual behaviors, visuomotor behaviours and the dissociation between these functions. These investigations confirm the sensitivity of visuomotor behaviours to atypical development and show that the dissociation between perceptual and visuomotor functions is disrupted under a range of neurodevelopmental conditions.
Access status: Open Access ,
Nutritional Ecology of Wild Bees: How Pollen Macronutrient Composition Shapes Development and Survival
(2025-07-23) Stephen, Khara Nyesha Whytnei; Rehan, Sandra
Bees rely on diverse floral resources to meet their nutritional needs, yet habitat loss, urbanization, and agricultural intensification are altering pollen availability and composition. Understanding the macronutrient profiles of pollen is central for pollinator health, as protein, lipids, and essential fatty acids influence bee development and survival. This thesis explores the nutritional composition of pollen from various plant species and its implications for bee health. Chapter I investigates the macronutrient content of 57 pollen species native to North America, revealing significant variation in non-esterified fatty acids (NEFAs), amino acids (AAs), and protein-to-lipid (P:L) ratios. Asteraceae pollen was particularly rich in essential amino acids, while mixed diets provided a balance of nutrients necessary for bee health. Chapter II examines how pollen macronutrient composition influences larval development in the small carpenter bee (Ceratina calcarata). Experimental rearing on black poplar (Populus nigra) and dandelion (Taraxacum officinale) pollen demonstrated that protein-rich arboreal pollen significantly enhanced bee growth, survival, and developmental rates. Bees on dandelion pollen alone exhibited delayed growth and reduced body size, while mixed diets mitigated nutritional stress. This research highlights the importance of nutritional diversity in pollen sources, emphasizing the role of tree pollen as an overlooked resource for pollinator conservation. As habitat loss and climate change continue to threaten pollinators, ensuring access to high-quality, nutritionally diverse floral resources may be key to sustaining bee populations and promoting ecosystem resilience.
Access status: Open Access ,
The Removal of D-Alanine from the Cell Wall Teichoic Acids of Staphylococcus Aureus by the fmtA Protein Drives Strain-Specific Viability Alterations Under Environmental Stress Conditions
(2025-07-23) Capota, Matthew; Golemi-Kotra, Dasantila
Antibiotic resistance of highly infectious Staphylococcus aureus makes eliminating this microorganism increasingly difficult, contributing to hospitalizations and severe infections worldwide. Wall teichoic acids (WTAs), linked to the bacterial cell wall, play key roles in resistance, cell lysis, and survival. WTAs are modified by the addition of D-alanine (D-Ala), which helps control bacterial surface charge and antibiotic resistance. S. aureus naturally cleaves D-Ala using the enzyme FmtA. We investigated whether purified FmtA could influence bacterial growth and survival by removing D-Ala from WTAs in vivo under favourable or unfavourable environments. Our findings confirmed that FmtA removes D-Ala from S. aureus and other Gram-positive bacteria. While S. aureus viability remained stable under favourable conditions, strain-specific responses emerged under variable stress. Notably, methicillin-resistant strains became more sensitive to oxacillin when exposed to FmtA. These results suggest that targeting WTA modifications could be a strategy to alter S. aureus viability under specific stress-inducing conditions.
Access status: Open Access ,
Biochemical and Structural Characterization of the S. Pombe La-Related Protein 1 (Slr1p)
(2025-07-23) Mansouri-Noori, Farnaz; Bayfield, Mark
La and La-related proteins (LARPs) are conserved RNA-binding proteins that share a characteristic La motif (LaM) and have important functions in RNA metabolism. Several LARP families exist where members possess specific domains that allow for binding to unique substrates. The LARP1 family, which includes a DM15 domain, binds a cohort of mRNAs encoding factors involved in the process of mRNA translation. These mRNAs contain a sequence of 5-15 pyrimidines in their 5′UTRs, immediately following the m7G cap, and are characterized as 5′ terminal oligopyrimidine (5′TOP) mRNAs. The DM15 domain of human LARP1 has been suggested to specifically recognize this motif, thereby affecting the translation and stability of 5′TOP mRNAs. However, the specific function of LARP1 in this context remains unclear. Intriguingly, the 5′TOP motif does not exist in yeast, and LARP1 orthologs in this system lack the characteristic DM15 domain. In this work, we characterize the S. pombe La-related protein 1, Slr1p, as an RNA-binding protein with conserved functions relative to other LARP1 orthologs. Through proteomic and transcriptomic studies, we show that Slr1p regulates the translation and stability of mRNAs that encode ribosomal proteins and other components of the translational apparatus in S. pombe. We further identify a 5′ Proximal AC-rich (5′PAC) motif, residing close to the start AUG, in these mRNAs and propose that they represent a cohort of proto-5′TOP mRNAs. Through structural analyses and mutagenesis studies, we show that the LaM of Slr1p is responsible for binding to the 5′PAC RNA motif, where mutagenesis of a single amino acid in our characterized binding site disrupts this interaction. We further demonstrate that Slr1p plays a role in adaptation to translation stress and that its phosphorylation status may allow for several functional states. Our findings are consistent with the conservation of LARP1 function across eukaryotes, and suggest that the involvement of this protein family in ribosomal protein mRNA translation and stability is influenced by a more fundamental LaM-dependent form of LARP1 regulation that is utilized in S. pombe.
Access status: Open Access ,
Effects of Anthropogenic Light and Noise on Anti-Predator Behaviour and Reproductive Success of an Urban Nesting Passerine
(2025-07-23) Scialla, Ileana; McKinnon, Laura
Species inhabiting urbanized habitats are continually facing challenges as urbanization intensifies. For urban birds, noise pollution may affect acoustic communication, and light pollution may affect circadian rhythms, yet very little research has been conducted in these areas. I investigated the effects of noise and light pollution on daily nest survival and anti-predator behaviour of American robins (Turdus migratorius) Toronto, ON Canada over 2 summers by monitoring nests and by using an observational and experimental approach. Anti-predator behaviours were influenced by light and noise pollution, but nest survival was unaffected. Higher levels of anthropogenic light and noise had no effect on nest survival; even experimentally increasing light levels at nests had no effect. Higher light and noise pollution did increase the frequency of anti-predator behaviours by nesting birds. Lastly, in areas of higher noise pollution robins were less likely to respond to experimental predator calls.
Access status: Open Access ,
Tethered To Telomeres: Characterizing The Form And Dynamic Elasticity Of Tethers In Anaphase Crane-Fly Spermatocytes
(2025-04-10) Economopoulos, Demetra; Connor, Steven
Elastic tethers connect sister chromosomes during anaphase in a broad range of animal cells, likely aiding in communication and coordination of movement. Calyculin A prevents dephosphorylation of tethers by protein phosphatase 1 (PP1) and, consequently, causes them to remain elastic throughout anaphase, resulting in backward movement. In my thesis experiments, I further explore the composition and behaviour of tethers. I expand upon existing research with Calyculin A, elucidating an optimal working concentration of 10 nM for investigating the reversibility of this drug on backward movement when rinsed out at various stages. I show that PP1 is critical during the onset of anaphase and that backward movement is not readily reversible. I also support the existing notion that tethers are made of titin, disproving the hypothesis that tethers are made of DNA. These contributions further enhance our understanding of tether composition and regulation during a central mechanistic phase of cell division.
Access status: Open Access ,
Finding Common Ground: Methods For Sustaining Citizen Science Engagement That Increase Indigenous Plant Biodiversity In Southwestern Ontario
(2025-04-10) Bava, Julia Maria; Bazely, Dawn R. A.
Nature-based solutions to address biodiversity loss require supports that reach beyond government grants. The Conservation Impact Bond (CIB) developed by Southwestern Ontario regional conservation charity, Carolinian Canada Coalition, is an example of a novel financial tool to incentivize biodiversity conservation by supporting citizen science. My research evaluated Carolinian Canada’s In The Zone Tracker and its allied programs. A systematic review of the literature about Canadian citizen science projects provided context. (1) The ITZ Program reversed plant biodiversity loss at a local level through planting projects that generated a self-reported increase in native species. (2) Information about citizen science projects was difficult to discover. Academic research into citizen science projects published in peer-reviewed literature creates a more permanent record than web-based, grey literature. (3) Citizen science projects do not necessarily improve science literacy. Rather, the ITZ tracker helped people to find common values and make positive, evidence-informed differences in their communities.
Access status: Open Access ,
Effects And Interactions Of Antibiotic, Butyrate, And Temperature On Sailfin Molly (Poecilia Latipinna) Metabolism And Gut Microbiota
(2025-04-10) Trovato, James; Bucking, Carol
Understanding the complex interactions between environmental factors, dietary supplements, and microbiome dynamics is crucial for optimizing fish health and growth, particularly in aquaculture settings. This study examines the effects of antibiotic, butyrate, and temperature treatments on the metabolism and gut microbiota of sailfin molly (Poecilia latipinna) alone and in combination. The results indicate that butyrate successfully restored the growth rates due to antibiotic exposure but had little effect when supplied to controls. Interestingly, while elevated temperature has been shown to promote growth through increased metabolic rates growth was not observed, possibly due to stress. Notably, there was a decrease in diversity in the microbiome because of antibiotic treatment. Further, both antibiotics and increased temperature lead to a decrease in the predicted functional capabilities of bacteria related to metabolism and health pathways after using PICRUSt analyses. While butyrate ameliorated the impacts on growth and metabolism caused by antibiotics, the microbiome was mostly unaffected, indicating that butyrate exerts its effects through the host directly. These findings suggest that butyrate could mitigate some negative impacts of antibiotics on fish growth and gut health as well as highlight some of the concerning effects of increasing environmental temperatures and antibiotic use. These insights may help develop strategies in fish population management and aquaculture practices, particularly those involving antibiotics and butyrate supplementation.
Access status: Open Access ,
Understanding Bumble Bee Community Changes And Floral Use In Southern Ontario.
(2025-04-10) Kerekes, Taylor; Colla, Sheila
Multiple wild bee species, including bumble bees, are in global decline due to habitat loss, reduced floral resources, and competition with managed honey bees. Monitoring previously surveyed sites is essential to assess ongoing impacts on bumble bee populations and identify trends over time. This research revisited areas in southern Ontario to examine changes in bumble bee abundance, diversity, and floral use (Chapter 1) and explored potential competition for floral resources between bumble bees and honey bees (Chapter 2). Results indicate that while some bumble bee species have increased over the last 50 years, many have declined, leading to an overall loss of diversity. Findings also reveal significant niche overlap between bumble bees and honey bees, suggesting competition for floral resources. This work informs conservation strategies, identifies species requiring focused efforts, and emphasizes the importance of maintaining diverse floral resources to support bumble bee populations.
Access status: Open Access ,
The Relative Importance Of Microclimatic Heterogeneity On Plant And Animal Communities In Deserts Of Southern California, U.S.A
(2025-04-10) Ghaziantafrishi, Nargol; MacDonald, Suzanne
This dissertation examines the intricate relationships between facilitation, environmental heterogeneity, and artificial habitat constructions in arid ecosystems, focusing on plant-animal and plant-plant interactions. By leveraging ecological principles, it explores the role of foundation plant species like Ephedra californica and Larrea tridentata in fostering ecosystem resilience and biodiversity under adverse conditions due to climate change, land use, and desertification. The study starts with an overview of facilitation theory, highlighting its importance in mitigating the negative effects of abiotic stressors in arid and semi-arid regions. It highlights the Stress Gradient Hypothesis (SGH) as a framework for understanding how competitive interactions can shift towards facilitation under harsh conditions, thus promoting the survival of diverse flora and fauna. The dissertation then delves into environmental heterogeneity, explaining its complex influence on ecosystem dynamics, species composition, and microclimatic regulation. Chapter 2 provides a detailed analysis of camera trapping techniques, offering optimal sampling design strategies for accurately estimating vertebrate abundance and richness. Chapter 3 examines the effects of artificial canopies on microclimate regulation. This chapter evaluates various eco-friendly fabrics, such as natural burlap, cotton, and nursery seedling fabric, in buffering microclimate through lab experiments measuring understory temperature, relative humidity, and radiation. Chapters 4 and 5 investigate how climatic variations and vegetation structure contribute to spatial and environmental heterogeneity, shaping flora and fauna diversity and abundance. A key aspect of the study is evaluating the effectiveness of artificial habitat construction as a conservation and restoration strategy in arid landscapes. Field experiments assess the microclimatic buffering capabilities of artificial shelters compared to natural vegetation in supporting vertebrate populations amid desertification in the Southwestern U.S.A. Overall, this dissertation enhances our understanding of the complex interplay between facilitation, environmental heterogeneity, and habitat modification in arid ecosystems. By uncovering the mechanisms behind these ecological processes, it provides valuable insights for conservation, management, and restoration efforts in regions vulnerable to anthropogenic disturbances and climate change.
Access status: Open Access ,
Examining The Role Of Lysyl Oxidase Enzymes In Atrial Fibrillation Induced By Volume Overload
(2025-04-10) Sherrard, Dana Evelyn; Backx, Peter
Atrial fibrillation (AF), the most prevalent cardiac arrhythmia, is linked to atrial electrical and structural remodelling. AF is associated with fibrosis; however, in models imposing atrial stretch, this occurs without changes in collagen transcription, suggesting fibrosis results from collagen stabilization by the Lysyl Oxidases (LOX) family of enzymes. To investigate this relationship, we established a murine aortic regurgitation (AR) model, which induces atrial stretch. AR mice exhibited increased AF susceptibility, decreased atrial refractoriness (AERP), elevated left atria (LA) fibrosis, and macrophage infiltration 2-fold compared to sham mice. LOXL2 inhibitor PXS-5382 reduced AF inducibility, shortened AF duration and attenuated fibrosis without affecting AERP. In contrast, the broader LOX inhibitor PXS-5505 prevented fibrosis without reducing AF inducibility in AR mice but exacerbated AF and fibrosis in sham mice. These results highlight LOXL2's critical role in atrial structural remodelling and AR-induced AF, suggesting it may be a promising therapeutic target for AF.
Access status: Open Access ,
Estimating Broad-Sense Heritability Of The Gut Microbiome In Western Honey Bees (Apis Mellifera)
(2025-04-10) Subramanian, Aishwarya; Zayed, Amro
The honey bee gut microbiome, crucial for bee health, may be shaped by both environmental and genetic factors. While differences in microbiomes exist between honey bee subspecies, it is unclear if genetic variation within a population influences this variation. This study estimated the broad-sense heritability of gut microbiome traits to explore patriline effects. We analyzed 500 workers from two colonies using 16S rRNA sequencing for microbiome characterization and genotyped them at 11 microsatellite loci. Results showed that patriline genetics marginally influenced the relative abundance of dominant microbiome taxa (18% to 24%) but did not significantly impact presence/absence of bacterial taxa or alpha and beta diversity. These findings suggest that environmental factors play a more substantial role in shaping the honey bee gut microbiome, indicating that microbiome-based interventions could benefit honey bees across populations.
Access status: Open Access ,
Elucidating Anthropogenic Impacts On Water Quality Through Spatial Heterogeneity In The Laurentian Great Lakes And The Global Fast Fashion Industry
(2025-04-10) Bailey, Kerrice Kesaynoi; Sharma, Sapna
Freshwater resources are vital for human survival including for consumption, transportation, and production of goods. We explore the impact of anthropogenic activity on water quality through: 1) the spatial heterogeneity in the northern nearshore regions of the Canadian Great Lakes and 2) the state of fast fashion in the top garment producing countries: China, Bangladesh, Vietnam, Turkey, India, and Indonesia. Water quality conditions varied spatially from oligotrophic conditions in Lake Superior to eutrophic conditions with elevated concentrations of nutrients and chlorophyll-a in Lake Erie. Further, we found that policy, sustainability and wastewater are key research areas in the top garment-producing countries. However, there was variation in the number of publications, terminology, knowledge gaps, and barriers that impede more sustainable garment production in the top garment-producing countries. We suggest investments in management and education to protect and use our freshwater resources more sustainably.
Access status: Open Access ,
The Impact Of Scene Context On Visual Object Recognition: Comparing Humans And Monkeys
(2025-04-10) Zafer, Anaa Salim; Kar, Kohitij
During natural vision, we rarely see objects on their own but rather within rich and complex environments. Understanding how the brain recognizes objects in these natural scenes by using contextual information remains a significant challenge. To explore neural mechanisms similar to human visual processing, it is crucial to have an animal model that behaves like humans. This way, the neural mechanisms we identify can offer insights relevant to the human brain. In this study, we investigated whether rhesus macaques could serve as a model for human context-driven object recognition. We did this by measuring their ability to identify visual objects with varying amounts, quality, and congruency of contextual cues. Our behavioral metrics showed remarkably similar context-dependent patterns between humans and monkeys. However, neural responses in the inferior temporal (IT) cortex of monkeys, who were not explicitly trained to recognize objects in context, could only partly explain this cross-species similarity. The behavioral similarities that were not explained by context-naive neural data highlight significant gaps in our understanding. Our findings reveal a fascinating alignment between human and monkey visual object processing that cannot be fully explained by neural activity in a key visual region.
Access status: Open Access ,
Investigating Pannexin1a-Mediated Mechanisms Of Pain And Neuroinflammation Using Zebrafish
(2025-04-10) Jeyarajah, Darren; Zoidl, George
This thesis explores the role of Panx1a in modulating pain and neuroinflammatory responses in zebrafish (Danio rerio). Nociception was induced using acetic acid (AA) treatments. Behavioral assays conducted on Panx1a knockout (KO) zebrafish larvae demonstrate significant alterations in response to acetic acid (AA)-induced pain. Pharmacological interventions using probenecid, a Panx1 inhibitor, and ibuprofen, a cyclooxygenase (COX) inhibitor, reveal their potential in modulating pain behaviors and rescuing nociceptive deficits. Furthermore, molecular analyses employing quantitative polymerase chain reaction (qPCR) and RNA sequencing (RNA-seq) elucidate the regulatory impact of Panx1a on gene expression related to nociception, neuroinflammation, and synaptic plasticity. In summary, this thesis provides evidence of Panx1a's involvement in pain and neuroinflammation, proposing zebrafish as a viable model for studying nociception.

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