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Orb-Weaver Diversity And Niche Partitioning In Ecuador’S Amazonian Foothills: What Spiders Can Reveal About Tree Fall Gaps, Streams, And Cultivated Areas, Riley Endries 2022 SIT Study Abroad

Orb-Weaver Diversity And Niche Partitioning In Ecuador’S Amazonian Foothills: What Spiders Can Reveal About Tree Fall Gaps, Streams, And Cultivated Areas, Riley Endries

Independent Study Project (ISP) Collection

As abundant predators at the top of arthropod food chains, spiders are excellent bioindicators. Araneae is a megadiverse and extremely understudied order, especially in the tropics. This study aims to investigate the diversity of orb-weaver spiders across a disturbance gradient and variety of habitat types as well as their microhabitat preferences and potential niche partitioning. Spider collection was performed on spiders of the families Araneidae, Tetragnathidae, and Theridiosomatidae in Sumak Kawsay in Situ biological reserve in the lower elevation cloud forest of Ecuador’s Andean foothills. Spiders and webs were observed and analyzed from primary and secondary forest tree fall gaps, …


Arthropod Assemblages At The Intersection Of Epiphyte And Soil Habitats: An Assessment Of Understory Level Nonvascular Epiphyte Communities And Their Connectivity Within A Tropical Montane Rainforest, David “Max” Jones 2022 SIT Study Abroad

Arthropod Assemblages At The Intersection Of Epiphyte And Soil Habitats: An Assessment Of Understory Level Nonvascular Epiphyte Communities And Their Connectivity Within A Tropical Montane Rainforest, David “Max” Jones

Independent Study Project (ISP) Collection

Canopy arthropods communities represent a disproportionate amount of global species richness (Stuntz 2001). Understanding arthropod composition and connectivity of lower epiphyte communities is important in understanding how canopy arthropods communities are formed and will respond to change (Floren and Linsenmair 1998). As such this study examined arthropod assemblages living within nonvascular epiphyte communities (epiphyte mats) living directly upon lower trunk regions of 24 trees in a tropical montane rain forest within the Santa Lucia Nature Reserve in Pichincha, Ecuador. Trees were assessed for size, epiphyte diversity, and epiphyte coverage before arthropod sampling within the epiphyte mats. Soil assessments were taken …


The Nesting Behavior Of Russet-Backed Oropendola On Sumak Allpa, Ecuador: An Analysis Of Nest Construction And Interactions With Competing Species, Claire Molina 2022 SIT Study Abroad

The Nesting Behavior Of Russet-Backed Oropendola On Sumak Allpa, Ecuador: An Analysis Of Nest Construction And Interactions With Competing Species, Claire Molina

Independent Study Project (ISP) Collection

Nests are the literal place of birth of bird species; they are incredibly important in the survival and reproduction of populations. Therefore, nesting behavior is a gateway into the lives and success of the animals. With the degradation of natural landscapes due to human activity, there is more of a need to monitor these nests to ensure healthy inhabitants. The Russet-backed Oropendola (Psarocolius angustifrons) creates unique, pendulous nests that are subject to piracy, parasitism, and predation; as well as weather phenomenon’s such as wind and rainstorms. This study describes the nest construction behavior, nest materials and nest architecture by collecting …


Tree To Tree: Phylogenetics Of Diverse Anura Using Portable Lab Equipment: Primer Optimization, Bioinformatic Pipeline, And Phylogenetic Analyses Reveal Potential New Species And Ability To Identify Evolutionary Relationships In A Hyper Diverse Anura Clade Using Nanopore Sequencing, Elinor Sterner 2022 SIT Study Abroad

Tree To Tree: Phylogenetics Of Diverse Anura Using Portable Lab Equipment: Primer Optimization, Bioinformatic Pipeline, And Phylogenetic Analyses Reveal Potential New Species And Ability To Identify Evolutionary Relationships In A Hyper Diverse Anura Clade Using Nanopore Sequencing, Elinor Sterner

Independent Study Project (ISP) Collection

The Corredor Llanganates-Sangay is an extremely significant region for conservation, coined a “gift to the earth” by the World Wildlife Fund. Understanding amphibians species and populations is key due to their roles as hyper sensitive bioindicators. In recent years, portable sequencing equipment (Mini PCR thermocyclers, Oxford Nanopore Technology’s MinION sequencer, etc) make genetic data collection in remote areas possible, greatly increasing potential for conservation genetics and genomics. This study uses portable equipment to sequence two mitochondrial loci in 104 Anuran samples collected in four sites in the Corridor and presents phylogenies of each gene as well as a concatenated phylogeny. …


Hummingbird Diversity, Abundance, And Feeding Interactions Across Three Floral Communities On Mount Totumas, Chiriquí, Panamá, Zachary Ginn 2022 SIT Study Abroad

Hummingbird Diversity, Abundance, And Feeding Interactions Across Three Floral Communities On Mount Totumas, Chiriquí, Panamá, Zachary Ginn

Independent Study Project (ISP) Collection

(Trochilidae) are a large Neotropical bird family of nectar-feeders that have evolved as pollinators of many Neotropical plants. Interactions between hummingbirds and plants form mutualistic networks that may change in structure over environmental and anthropogenic gradients. While the unique dynamics of hummingbird diversity and floral interactions have been studied throughout the Neotropics, differing drivers between locations emphasizes the need for further local research. This deficit is especially crucial in biodiverse and understudied locations like the Western Highlands of Panamá. In this study, I investigated how hummingbird diversity, abundance, and floral interactions differed between Cloud Forest, Garden, and Oak Forest on …


Modulation Of Hepatic Amyloid Precursor Protein And Lipoprotein Receptor-Related Protein 1 By Chronic Alcohol Intake: Potential Link Between Liver Steatosis And Amyloid-Β, Jerome Garcia, Rudy Chang, Ross A. Steinberg, Aldo Arce, Joshua Yang, Peter Van Der Eb, Tamara Abdullah, Devaraj V. Chandrashekar, Syndey M. Eck, Pablo Meza, Zhang-Xu Liu, Enrique Cadenas, David H. Cribbs, Neil Kaplowitz, Rachita K. Sumbria, Derick Han 2022 University of La Verne

Modulation Of Hepatic Amyloid Precursor Protein And Lipoprotein Receptor-Related Protein 1 By Chronic Alcohol Intake: Potential Link Between Liver Steatosis And Amyloid-Β, Jerome Garcia, Rudy Chang, Ross A. Steinberg, Aldo Arce, Joshua Yang, Peter Van Der Eb, Tamara Abdullah, Devaraj V. Chandrashekar, Syndey M. Eck, Pablo Meza, Zhang-Xu Liu, Enrique Cadenas, David H. Cribbs, Neil Kaplowitz, Rachita K. Sumbria, Derick Han

Pharmacy Faculty Articles and Research

Heavy alcohol consumption is a known risk factor for various forms of dementia and the development of Alzheimer’s disease (AD). In this work, we investigated how intragastric alcohol feeding may alter the liver-to-brain axis to induce and/or promote AD pathology. Four weeks of intragastric alcohol feeding to mice, which causes significant fatty liver (steatosis) and liver injury, caused no changes in AD pathology markers in the brain [amyloid precursor protein (APP), presenilin], except for a decrease in microglial cell number in the cortex of the brain. Interestingly, the decline in microglial numbers correlated with serum alanine transaminase (ALT) levels, suggesting …


Prenatal Choline Supplementation During Maternal Obesity Alters Offspring Response To Western Diets, Hunter W. Korsmo 2022 The Graduate Center, City University of New York

Prenatal Choline Supplementation During Maternal Obesity Alters Offspring Response To Western Diets, Hunter W. Korsmo

Dissertations, Theses, and Capstone Projects

Maternal obesity has led to an increase in adverse offspring developmental outcomes and a greater risk for long-term metabolic diseases. Choline, a semi-essential nutrient, can be incorporated into phosphatidylcholine (PC) as well as sphingomyelin (SM) and donate its labile methyl group for the remethylation of homocysteine after choline is oxidized to betaine. Prenatal choline insufficiency has been related to maternal obesity and metabolic diseases, such as metabolic associated fatty liver disease (MAFLD). Choline may interact with maternal obesity to influence the programming offspring.

Chapter 1 presents an introduction of choline and the various clinical outcomes associated with choline supplementation during …


The Effects Of Prenatal Cannabis Exposure On The Basolateral Amygdala, Karen KW Wong 2022 Western University

The Effects Of Prenatal Cannabis Exposure On The Basolateral Amygdala, Karen Kw Wong

Undergraduate Student Research Internships Conference

Clinical and preclinical studies indicate prenatal cannabis exposure (PCE) pathologically affects fetal brain development and may increase vulnerability to neuropsychiatric disorders, including schizophrenia and mood/anxiety disorders. In review research from our lab suggests that fetal exposure to Δ9-THC sex-selectively impairs mesocorticolimbic (MCL) circuit function. However, there is a distinct lack of focus on PCE models on the BLA. The BLA plays a central role within the MCL where it directly interacts with the VTA, PFC and HIPP. Importantly, our model exhibits significant VTA hyperdopaminergic activity, and sex-specific alterations to PFC/HIPP glutamate firing, alongside region- and sex-specific changes in dopamine (DA), …


Myeloarchitectonic Maps Of Cat Auditory Cortex, Austin Robertson 2022 The University of Western Ontario

Myeloarchitectonic Maps Of Cat Auditory Cortex, Austin Robertson

Electronic Thesis and Dissertation Repository

The cerebral cortex contains myriad cortical areas that differ in structure, function, and connectivity. Current methods of delineating cortical structures and their subregions are insufficient for in vivo applications, either being highly invasive or requiring a detailed knowledge of a region’s tuning properties. To address this, we seek to establish a structural biomarker capable of delineating the cortex that possesses a non-invasive correlate. We explore myelin as a potential candidate by evaluating its efficacy in parcellating the feline auditory cortex through the generation of depthwise myelin density profiles for each of the 13 auditory cortical subregions. Our analyses revealed significant …


Impacts On Fast-Start Performance: How Do Group Size And Habitat Degradation Alter The Escape Behavior Of A Schooling Coral Reef Fish?, Monica D. Bacchus 2022 Nova Southeastern University

Impacts On Fast-Start Performance: How Do Group Size And Habitat Degradation Alter The Escape Behavior Of A Schooling Coral Reef Fish?, Monica D. Bacchus

All HCAS Student Capstones, Theses, and Dissertations

Escaping predation is essential for species survival, but prey must effectively match their response to the perceived threat imposed by a predator. Fish evaluate their surroundings using several sensory stimuli, including olfactory, visual, auditory, and mechanical cues. A range of taxa use the fast-start response to evade predators, including fishes, sharks, and larval amphibians. While the fast-start response (rapid bursts of swimming) is extensively studied in solitary fishes, the factors that mediate the collective escape response in schools of fish have historically been investigated far less. To address this knowledge gap, the collective escape behavior and individual escape performance of …


Effects Of An Injectable Zinc Solution At Weaning As An Alternative Castration Method In Beef Cattle, Reagan Nicole Cauble 2022 University of Arkansas, Fayetteville

Effects Of An Injectable Zinc Solution At Weaning As An Alternative Castration Method In Beef Cattle, Reagan Nicole Cauble

Graduate Theses and Dissertations

Two experiments were conducted to investigate a 1 mL intratesticular zinc (100 mg Zn) injection administered into each testicle at weaning (Z) and its effects on growth, health, behavior and testosterone. In the first experiment, beef bulls were assigned randomly to treatment at birth: 1) surgically castrated at birth (S; n = 37) or 2) Z (n = 37). Testicular thickness differed by day (P < 0.01) for Z. Testosterone concentrations were greater in Z by d 77 and remained so through d 280 (P = 0.02) compared to S. Zinc injected calves were heavier at the trail’s conclusion (P ≤ 0.04), had greater ADG overall (P < 0.01), heavier hot carcass weight (P = 0.01), and greater lean muscle area (P = 0.01) compared to S; but a lower marbling score (P < 0.01). Yield Grade, dressed carcass yield and fat thickness were similar (P ≥ 0.14). Zinc injected calves had greater haptoglobin (Hp) concentrations (P < 0.01). Zinc injected calves had greater concentrations of white blood cells on d 1 and 2 and greater concentrations and proportions of neutrophils on d 1, 2 and 3 (P < 0.01). Conversely, S had a greater percentage of lymphocytes on d 1, 2 and 3 and a lower ratio of neutrophils to lymphocytes during that same time (P < 0.01). Zinc injected calves spent more time on their side or sternum on d 1 and more time on their side on d 2 while S spend more time standing during that time (P < 0.01). During d 3, 4, 5, and 6, Z stood more while S laid on their sternum (P < 0.01). In trail 2, beef bulls were allocated randomly to treatment one week post weaning: 1) banded (B; n = 42) or 2) Z (n = 39). Body weights were similar (P ≥ 0.39) but ADG improved for Z compared to B (P = 0.05). Testosterone concentrations were greater in Z compared to B (P ≤ 0.02). Testicular width in Z differed by d (P < 0.01). Zinc castrated calves spent more time on their side compared to B one day post castration (P = 0.03) until d 3 and 4 where B spent more time on their side (P ≤ 0.02). Banded calves stood more the first two days (P ≤ 0.01). On days 3, 4, 5, and 6, Z stood more (P ≤ 0.01) while B were on their sternum (P ≤ 0.03). Banded calves had lower Hp concentrations compared to Z (P ≤ 0.01). Total white blood cell concentrations, proportions and concentrations of neutrophils, and proportion of lymphocytes were greater in Z compared to B on d 1, 2, and 3 (P ≤ 0.01). There was no interaction between treatments over time for IL1β, IL6, and TNFα expression (P ≥ 0.83). The findings in both studies indicate that intratesticular Zn injections at weaning can improve growth performance and some carcass attributes but produce a heightened inflammatory and immune response and cause discomfort. Injecting zinc, as formulated and administered in these trails, does not result in complete castration of beef calves at this age and therefore cannot be considered a true castration alternative.


Effect Of Sensory Additives On Sow Lactation Performance, Subsequent Reproductive Performance, And Nursey Pig Performance, Nathan E. Davis 2022 University of Arkansas, Fayetteville

Effect Of Sensory Additives On Sow Lactation Performance, Subsequent Reproductive Performance, And Nursey Pig Performance, Nathan E. Davis

Graduate Theses and Dissertations

Maximizing nutrient intake during lactation is vital to sow performance as well as litter performance. The aim of these studies was to evaluate the impact of a sensory additive on sow lactation performance and nursery pig performance. Five groups of sows were farrowed, three during winter (October, December and January) and two during summer months (June, July, August). Sows were weighed, and back fat depth was measured, at 110 d of gestation prior to entering the lactation room, and again at weaning. The sows were blocked by parity, and then allotted by BW at d 110 to Control or 0.075% …


The Role Of The Hypoxia-Inducible Factor 2 In Pancreatic Cancer: Mechanisms Of Tumor Immunosuppression And Intestinal Radioprotection, Carolina Garcia Garcia 2022 The Texas Medical Center Library

The Role Of The Hypoxia-Inducible Factor 2 In Pancreatic Cancer: Mechanisms Of Tumor Immunosuppression And Intestinal Radioprotection, Carolina Garcia Garcia

Dissertations & Theses (Open Access)

Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease with dismal prognosis. The only curative option for patients is surgery, but over 80% of patients are not surgical candidates. Unfortunately, PDAC is resistant to the three remaining options. PDAC is characterized by a profoundly hypoxic and immunosuppressive stroma, which contributes to its therapeutic recalcitrance. Alpha-smooth muscle actin+ (αSMA+) cancer-associated fibroblasts (CAFs) are the most abundant stromal component, as well as mediators of stromal deposition. The hypoxia-inducible factors (HIF1 and HIF2) coordinate responses to hypoxia, yet, despite their known association to poor patient outcomes, their functions within the PDAC tumor microenvironment (TME) …


Intestinal Microbiota Analysis Of Broiler Chickens Under Necrotic Enteritis Challenge And Tributyrin Supplementation, Taylor Nicole McKinney 2022 University of Arkansas, Fayetteville

Intestinal Microbiota Analysis Of Broiler Chickens Under Necrotic Enteritis Challenge And Tributyrin Supplementation, Taylor Nicole Mckinney

Graduate Theses and Dissertations

Poultry is a staple protein source for most of the planet. Until recently, antibiotic growth promoters (AGPs) were used to prevent illnesses in commercial chicken production. Currently, this is not possible due to regulations and consumer concern, but without such a preventative, diseases like necrotic enteritis (NE) have reemerged, posing a threat to bird health, and ultimately, our food source. Necrotic enteritis is a severe gastrointestinal disease caused by the gram-positive pathogen, Clostridium perfringens. Clinical features of this disease are diarrhea, intestinal lesions, and death, with a high transmission rate. In a subclinical form, growth performance is diminished and is …


The Role Of Microbiota On Campylobacter Jejuni Colonization And Growth Performance In Broiler Chickens, Ayidh Almansour 2022 University of Arkansas, Fayetteville

The Role Of Microbiota On Campylobacter Jejuni Colonization And Growth Performance In Broiler Chickens, Ayidh Almansour

Graduate Theses and Dissertations

The successful poultry production at modern era comes from the vertical integratedindustrialization, which has fundamentally changed how animals have been living for millions of years. Antimicrobial growth promoters have been used to sustain the efficient industrialized animal production, driving antimicrobial overuse and resistance. Because of the increasing pressure from consumer’s concerns and government regulations, it is urgent to develop antimicrobial free alternatives as growth promoters in poultry production, but few effective antimicrobial alternatives are currently available. Campylobacter jejuni is one of the worldwide prevalent foodborne bacterial pathogens mainly transmitted from poultry. However, few mechanisms are available on why C. jejuni …


Early-Exercise Effects On Mice Tendon Remodeling, Miles Valencia 2022 California State University, San Bernardino

Early-Exercise Effects On Mice Tendon Remodeling, Miles Valencia

Electronic Theses, Projects, and Dissertations

Tendons connect and transmit energy between muscles and bones and play a key role in movement. Tendon remodels by breaking down and absorbing tendon components including collagen fibers and elastin while replacing them with newly formed tendon. These processes can be influenced by short- and long-term factors such as exercise and aging; the magnitude of influence on tendon remodeling remains unclear. I researched the effects of maturation and exercise on tendon remodeling using a mice colony artificially selected for high voluntary wheel running called high-runner mice. Control and high-runner linetype mice were separated into 2 age cohorts that started training …


Online Privacy Challenges And Their Forensic Solutions, Bandr Fakiha 2022 Umm Al-Qura University, Saudi Arabia

Online Privacy Challenges And Their Forensic Solutions, Bandr Fakiha

Journal of the Arab American University مجلة الجامعة العربية الامريكية للبحوث

In the digital age, internet users are exposed to privacy issues online. Few rarely know when someone else is eavesdropping or about to scam them. Companies, governments, and individual internet users are all vulnerable to security breaches due to the challenges of online privacy ranging from trust and hierarchical control to financial losses. As systems advance, people are optimistic that forensic science will provide long-term interventions that surpass the current solutions, including setting stronger passwords and firewall protection. The future of online privacy is changing, and more practical interventions, such as email, malware, mobile, and network forensics, must be integrated, …


Ciliogenesis Mechanisms Mediated By Pak2-Arl13b Signaling In Brain Endothelial Cells Is Responsible For Vascular Stability, Karthikeyan Thirugnanam, Shubhangi Prabhudesai, Emma Van Why, Amy Pan, Ankan Gupta, Koji Foreman, Rahima Zennadi, Kevin R. Rarick, Surya M. Nauli, Sean P. Palacek, Ramani Ramchandran 2022 Medical College of Wisconsin

Ciliogenesis Mechanisms Mediated By Pak2-Arl13b Signaling In Brain Endothelial Cells Is Responsible For Vascular Stability, Karthikeyan Thirugnanam, Shubhangi Prabhudesai, Emma Van Why, Amy Pan, Ankan Gupta, Koji Foreman, Rahima Zennadi, Kevin R. Rarick, Surya M. Nauli, Sean P. Palacek, Ramani Ramchandran

Pharmacy Faculty Articles and Research

In the developing vasculature, cilia, microtubule-based organelles that project from the apical surface of endothelial cells (ECs), have been identified to function cell autonomously to promote vascular integrity and prevent hemorrhage. To date, the underlying mechanisms of endothelial cilia formation (ciliogenesis) are not fully understood. Understanding these mechanisms is likely to open new avenues for targeting EC-cilia to promote vascular stability. Here, we hypothesized that brain ECs ciliogenesis and the underlying mechanisms that control this process are critical for brain vascular stability. To investigate this hypothesis, we utilized multiple approaches including developmental zebrafish model system and primary cell culture systems. …


Maternal Responses In The Face Of Infection Risk, Patricia C. Lopes, Brenna M. G. Gormally, Aubrey Emmi, Delilah Schuerman, Chathuni Liyanage, Ursula K. Beattie, L. Michael Romero 2022 Chapman University

Maternal Responses In The Face Of Infection Risk, Patricia C. Lopes, Brenna M. G. Gormally, Aubrey Emmi, Delilah Schuerman, Chathuni Liyanage, Ursula K. Beattie, L. Michael Romero

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

When animals are sick, their physiology and behavior change in ways that can impact their offspring. Research is emerging showing that infection risk alone can also modify the physiology and behavior of healthy animals. If physiological responses to environments with high infection risk take place during reproduction, it is possible that they lead to maternal effects. Understanding whether and how high infection risk triggers maternal effects is important to elucidate how the impacts of infectious agents extend beyond infected individuals and how, in this way, they are even stronger evolutionary forces than already considered. Here, to evaluate the effects of …


Effects Of Chronic Stress On Safety Processing And Physiology In The Medial Prefrontal-Amygdala-Basal Forebrain Circuit, Itamar S. Grunfeld 2022 The Graduate Center, City University of New York

Effects Of Chronic Stress On Safety Processing And Physiology In The Medial Prefrontal-Amygdala-Basal Forebrain Circuit, Itamar S. Grunfeld

Dissertations, Theses, and Capstone Projects

Chronic stress increases generalization of fear to non-threatening cues, a key symptom in numerous psychiatric mood disorders. However, the mechanisms through which stress impacts safety learning remain poorly understood. To probe the relationship between stress and safety learning, this dissertation employed multiple behaviors, in conjunction with in-vivo multisite physiology during explicit safety and fear discrimination learning. In Chapter 1, I outline the role of chronic stress in driving neurological adaptations that result in generalized fear and highlight how this occurs because of impaired safety cue encoding. In Chapter 2, I show that chronic stress in the form of social defeat …


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