Biology Commons^™

The Role Of Semaphorins In Response To Injury In C. Elegans Neurons, Maria Belen Harreguy Alfonso

Dissertations

When neural tissue is injured by trauma, delicate neuronal processes such as axons and dendrites are prone to lesion damage and often disconnect. The molecular, cellular, and circuit mechanisms that underlie the regrowth and reconnection of these processes and the recovery of behavior are major challenges in the fields of neuroscience, regeneration, and resilience. At the molecular and cellular levels, signaling pathways that mediate neuronal growth cone guidance during development can play a role in neuronal regeneration and recovery from injury. One family of signaling proteins involved in this process comprises the highly conserved semaphorins and their receptors, the plexins. …

The Role Of Trees In Reducing The Urban Heat Island Effect On The New Jersey Institute Of Technology Campus, Newark, Nj, Dahlia Mansour

Theses

Every year, an estimated 12.3 million tons of glass are generated in the United States. Of all glass generated, only 3.1 million tons are recycled. Despite the near endless recyclability of glass waste, recycling rates in the United States remain low. This is primarily due to the lack of color separation and presence of non-recyclable materials associated with single-stream curbside collection used in many municipalities throughout the country. These factors make recycled glass unusable for many glass bottle manufacturers, causing the majority of glass placed in a recycling bin to eventually be landfilled. The purpose of this research is to …

The Evaluation Of Carbon Benefits Produced By Urban Street Trees, Hanyu Wang

Theses

Urban tree service and urban forestry are important fields that focus on the care and management of trees in urban areas. Urban trees provide numerous benefits around all aspect, including carbon storage, improving air and water qualities. Carbon storage refers to the process of removing carbon dioxide (CO2) from the atmosphere and storing it in various reservoirs, and in this case, in trees and forests.

i-Tree is a suite of software tools developed by the United States Forest Service that provides a range of resources for assessing and managing forests. i-Tree Eco is one of the more used tools from …

Brainless But Smart: Investigating Cognitive-Like Behaviors In The Acellular Slime Mold Physarum Polycephalum, Subash Kusum Ray

Dissertations

Evolutionary pressures to improve fitness, have enabled living systems to make adaptive decisions when faced with heterogeneous and changing environmental and physiological conditions. This dissertation investigated the mechanisms of how environmental and physiological factors affect the behaviors of non-neuronal organisms. The acellular slime mold Physarum polycephalum was used as the model organism, which is a macroscopic, unicellular organism, that self-organizes into a network of intersecting tubules. Without using neurons, P. polycephalum can solve labyrinth mazes, build efficient tubule networks, and make adaptive decisions when faced with complicated trade-offs, such as between food quality and risk, speed and accuracy, and exploration …

Flexibility Vs Consistency: Quantifying Differences In Neuromodulatory Elicited Patterns Of Activity, Elizabeth M. Cronin

Dissertations

Central pattern generating circuits underly fundamental behaviors such as respiration or locomotion and are under the influence of neuromodulators. The presence of neuromodulators is thought to confer flexibility to these circuits to generate distinct patterns of activity to meet distinct behavioral needs. Network output flexibility can be achieved by distinct classes of neuromodulators, those which have convergent cellular actions but divergent circuit actions or by those which have divergent cellular actions but convergent circuit actions.

Both classes of neuromodulator exist in the stomatogastric nervous system of the crab Cancer borealis and influence the activity of a central pattern generating circuit …

Repeated Low-Level Blast Induces Chronic Neuroinflammation And Neurobehavioral Changes In Rat Models, Arun Reddy Ravula

Dissertations

Blast-induced neurotrauma (bTBI) is a signature medical concern for military personnel when they are exposed to explosions in active combat zones. However, soldiers as well as law enforcement personnel are also repeatedly exposed to low-level blasts during training sessions with heavy weaponries as part of combat readiness. Service personnel who sustain brain injuries from repeated low-level blasts (rLLBs) do not display overt pathological symptoms immediately but rather develop cognitive impairments, attention deficits, anxiety, and sleep disturbances over time. An improved rat model of rLLB was developed in this thesis by applying controlled low-level blast pressures (10 psi) repeated five times …

The Interplay Of The Physical Landscape And Social Dynamics In Shaping Movement Of African Savanna Elephants (Loxodonta Africana), Maggie Wisniewska

Dissertations

Free ranging African savanna elephants (Loxodonta africana) are increasingly impacted by human-induced habitat loss and poaching for ivory. Because elephants live in tightly knit groups, this combination of threats not only reduces the size of their populations but also degrades their social interactions. Long-term relationships with socially competent individuals, such as experienced seniors, benefit the ability of other group members to access limiting resources and avoid danger. Understanding how anthropogenic pressure may affect persistence of elephant populations is important, because elephants are an economically important keystone species. This doctoral thesis characterizes how individual elephants influence the movement of their social …

These Fish Were Made For Walking: Morphology And Walking Kinematics In Balitorid Loaches, Callie Hendricks Crawford

Dissertations

Terrestrial excursions have been observed in multiple lineages of marine and freshwater fishes. These ventures into the terrestrial environment may be used when fish are searching out new habitat during drought, escaping predation, laying eggs, or seeking food sources. The physiological demands for life under water and on land are vastly different and require different functional adaptations. Fish with terrestrial excursions must be capable of dealing with the stresses of both aquatic and terrestrial environments for varying periods of time. To deal with these stresses, amphibious fishes exhibit many morphological and behavioral adaptations. These adaptations have led to a range …

Development Of Deep Learning Neural Network For Ecological And Medical Images, Shaobo Liu

Dissertations

Deep learning in computer vision and image processing has attracted attentions from various fields including ecology and medical image. Ecologists are interested in finding an effective model structure to classify different species. Tradition deep learning model use a convolutional neural network, such as LeNet, AlexNet, VGG models, residual neural network, and inception models, are first used on classifying bee wing and butterfly datasets. However, insufficient data sample and unbalanced samples in each class have caused a poor accuracy. To make improvement the test accuracy, data augmentation and transfer learning are applied. Recently developed deep learning framework based on mathematical morphology …

The Role Of Irak-1 Transcripts In Sepsis, Adithya Subramanian Sahasranamam

Theses

Sepsis is a complex, life-threatening syndrome that can lead to systemic organ failure and dysfunction. Its high morbidity and mortality rates makes it a critical global health issue. The primary factors at play during sepsis are abnormal inflammation and a lack of oxygen supply to the tissues and muscles. The toll-like receptors play a crucial role in eliciting innate immune in response to infection, primarily through the interleukin-1 receptor-associated kinase (IRAK) pathways. Disturbances in the homeostasis of IRAK signaling cascades can lead to immune dysfunction. n this paper, we review the molecular mechanisms of IRAK-1, an important mediator of TLR-induced …

Efficient Approximations For Stationary Single-Channel Calcium Nanodomains, Yinbo Chen

Dissertations

Mathematical and computational modeling plays an important role in the study of local Ca2+ signals underlying many fundamental physiological processes such as synaptic neurotransmitter release and myocyte contraction. Closed-form approximations describing steady-state distribution of Ca2+ in the vicinity of an open Ca2+ channel have proved particularly useful for the qualitative modeling of local Ca2+ signals. This dissertation presents several simple and efficient approximants for the equilibrium Ca2+ concentration near a point source in the presence of a mobile Ca2+ buffer, which achieve great accuracy over a wide range of model parameters. Such approximations provide an efficient method for estimating Ca2+ …

Genetic Population Structure And Microbiome Of German Cockroaches In Urban Environments, Xueyang Fan

Dissertations

Pests of human habitats may harbor and disperse pathogens that cause human disease. One such pest is the German cockroach (Blattella germanica), which is known to harbor numerous pathogens, including Klebsiella and Pseudomonas. The aim of this study is to reveal the importance of the German cockroach as a potential vector of human medically important diseases. To do so, this study investigates German cockroach population structure and their associated bacterial microbiome in urban residential environments. Ninety German cockroaches are collected from three residential apartment buildings in three New Jersey cities. Samples are caught by glue traps and stored at -20°C. …

Plant Evolution And Urbanization: Quantifying The Effects Of Natural Selection In Shaping Shepherd’S Purse (Capsella Bursa-Pastoris) Populations In New York City, Rebecca Panko

Dissertations

The aim of this study is to quantify the effects of natural selection in shaping Capsella bursa-pastoris populations along an urban-rural gradient in New York City.

A reciprocal transplant experiment with 168 lab-germinated C. bursa-pastoris seedlings from both urban and rural populations are grown in eight paired home and away sites distributed throughout the New York metropolitan area. Sites are visited approximately thirteen times to record plant fitness. There is evidence for local adaptation of urban populations: urban plants have longer reproductive durations and produce more seed pods in urban environments. These findings suggest that urban plants are better adapted …

The Roles Of Inhibition In C. Elegans Locomotion, Lan Deng

Dissertations

Inhibition plays important roles in modulating neural activities at different levels from small synapses to brain regions, and different systems from sensory to motor. To achieve translocation, locomotor systems produce alternation of antagonist muscles, including axial posture and limb movement and alternation. In the nematode C. elegans, a cross-inhibition circuit, involving excitatory cholinergic and inhibitory GABAergic motoneurons, is believed to generate the dorsoventral alternation of body-wall muscles that supports backward undulatory locomotion. This dissertation challenges this prevalent hypothesis, delves into studying different roles of inhibition, and depicts the expression pattern and functional role of ionotropic GABAA receptor, UNC-49, in motoneurons …

Mitochondria Imaging And Targeted Cancer Treatment, Tinghan Zhao

Dissertations

Mitochondria are essential organelles as the site of respiration in eukaryotic cells and are involved in many crucial functions in cell life. Dysfunction of mitochondrial metabolism and irregular morphology have been frequently found in human cancers. The capability of imaging mitochondria as well as regulating their microenvironment is important both scientifically and clinically. Mitochondria penetrating peptides (MPPs), certain peptides that are composed of cationic and hydrophobic amino acids, are good candidates for mitochondria targeting. Herein, a novel MPP, D-argine-phenylalanine-D-argine-phenylalanine-D-argine-phenylalanine-NH₂ (rFrFrF), is conjugated with a rhodamine-based fluorescent chromophore (TAMRA). The TAMRA-rFrFrF probe exhibits advantageous properties for long-term mitochondria tracking of …

Methods To Improve The Remediation Of Polycyclic Aromatic Hydrocarbons (Pahs) In Aerobic And Anaerobic Environments, Brian Wartell

Dissertations

Oil spills occur regularly in terrestrial environments and crude oil can contain many compounds that are highly resistant to degradation. Among these compounds are high levels of polycyclic aromatic hydrocarbons (PAHs) which are not only toxic but can also be carcinogenic and/or mutagenic. The first chapter of this dissertation includes an extensive review chapter on the variables affecting the anaerobic degradation of hydrocarbons, with a particular focus on PAHs. Electron acceptors, electron donors, temperature, salinity, pH all play key roles in determining the possibility effective of effective degradation occurring. Thus, by addressing solutions, such as biostimulation, improving environmental variables for …

Direct And Indirect Controls On Bee Community Composition, Caroline Marie Devan

Dissertations

Bees are important pollinators, critical for the continued survival of plants in both natural and agricultural ecosystems. Diverse bee communities have been shown to increase richness in plant communities and plant reproduction depends upon bee community richness. Yet there is growing concern that pollinators, especially bees, are declining globally. This dissertation focuses on evaluating the mechanisms responsible for bee community composition in order to promote bee conservation in natural systems and their restoration in human-dominated urban and agricultural landscapes.

Bee populations are impacted directly by three things: floral resources, nesting resources and risk, primarily from natural enemies. Bees are indirectly …

Improving Methods To Estimate Time Of Death From Body Temperature, Carly Berdan

Theses

By protocol, ambient and body temperatures are collected at every investigated death scene. These data has been used since 1839 to estimate the time of death, a crucial factor when it comes to cases of unnatural deaths and homicides. The Glaister Equation and Henssge's nomogram, commonly used to calculate estimated time of death, are inconsistent and often do not agree with each other. Therefore, my objective was to evaluate and improve them.

I collected data in the field and consistently measured temperature data. Furthermore, I was granted access to a database of every death in New Jersey and published data. …

Regulation Of Voltage-Gated K+ Currents In Motor Neurons: Activity-Dependence And Neuromodulation, Dalia Salloum

Dissertations

Neuronal output is shaped by extrinsic modulation as well as modulation of intrinsic properties of individual neurons, mediated by activity-dependent changes in the expression levels of voltage-gated ionic currents. Activity-dependent regulation of ionic currents is a mechanism by which electrical output of a neuron feeds back onto the expression of its own ion channels to alter cellular excitability in response to stimuli. Neurons alter their intrinsic properties to achieve long lasting changes involved in development, learning and memory formation and vital functions of organ systems such as locomotion and digestion. At the same time, plasticity of neuronal excitability driven by …

Biophysical Mechanisms Of Frequency-Dependence And Its Neuromodulation In Neurons In Oscillatory Networks, David Michael Fox

Dissertations

In response to oscillatory input, many isolated neurons exhibit a preferred frequency response in their voltage amplitude and phase shift. Membrane potential resonance (MPR), a maximum amplitude in a neuron’s input impedance at a non-zero frequency, captures the essential subthreshold properties of a neuron, which may provide a coordinating mechanism for organizing the activity of oscillatory neuronal networks around a given frequency. In the pyloric central pattern generator network of the crab Cancer borealis, for example, the pacemaker group pyloric dilator neurons show MPR at a frequency that is correlated with the network frequency. This dissertation uses the crab …

Regulation Of Mtorc1 By Homocysteine And Its Effects On Autophagy In Human And Mouse Neuronal Tissues, Khoosheh Khayati

Dissertations

The molecular mechanisms leading to and responsible for age-related, sporadic Alzheimer’s disease (AD) remain largely unknown. It is well documented that aging patients with elevated levels of the amino acid metabolite homocysteine (Hcy) are at high risk of developing AD. The impact of Hcy on molecular clearance pathways in mammalian cells, including in-vitro cultured induced pluripotent stem cell-derived forebrain neurons and in-vivo neurons in mouse brains is investigated in this research project. Exposure to high Hcy levels results in up-regulation of the mechanistic target of rapamycin complex 1 (mTORC1) activity, one of the major kinases in cells that is tightly …

Using A Bio-Inspired Model To Understand The Evolution Of The Remora Adhesive Disk, Kaelyn Mykel Gamel

Theses

Manmade adhesives often fail on wet, compliant surfaces, which can result in poor performance when attaching sensors in medical, defense, and research situations. However, a number of fishes have evolved adhesive discs that allow adhesion to surfaces under challenging wetted conditions. A remarkable evolutionary advancement is found in the family of echenidae, colloquially known as the remora. In particular, the remora fishes have the ability to attach to wet, compliant bodies under high shear conditions for extended periods of time. This research addresses the lack of underwater adhesives by using remora adhesion as a bioinspired model. Evolution has taken …

Otolith Morphologies In The Genus Sinocyclocheilus, Iqra Iqbal

Theses

Sinocyclocheilus is a genus of Cyprinid fish found in southern China. This genus contains 68 species of which 40 species have adaptations for life in cave habitats. A common adaptation seen in fish that live in caves with no light is the loss of vision. Such cavefish must therefore rely on other sensory modalities to capture prey, communicate between conspecifics, and potentially avoid predators. Previous studies have identified sensory adaptations in cavefish, including the increase in size and number of mechanoreceptors. Sinocyclocheilus are hearing specialists, and it is possible that cave species of this genus have increased reliance on hearing …

Changes In Morphology During The Development Of The Horn And Hump Of The Chinese Cavefish Sinocyclocheillus Furcodorsalis, Michelle Pluviose

Theses

The genus Sinocyclocheilus endemic to southern China and contains many cavefish species. There are approximately sixty species, of which roughly forty are cave-adapted. Cave Sinocyclocheilus are characterized not only by lack of pigmentation and eyes depending on the species, but also by a unique prominent horn on the top of the skull and dorsal hump rostral under the dorsal fin. The horn and the hump are generally considered troglomorphic characteristics, although their functions are still elusive. Here, the development of these distinctive structures in the species, S. furcodorsalis, was examined by using micro CT scans. The horn of the …

Multisensory Integration In Weakly Electric Fish, Andrea Roeser

Theses

Animals integrate information from across sensory systems, such as vision and hearing, to improve perception. To understand how neural circuits in the central nervous system integrate information from different senses, the responses of midbrain neurons to two categories of electrosensory stimuli in Eigenmannia virescens were studied. The first category of stimulus is electrical signals with frequencies below 50 Hz that are encoded in the activity of ampullary receptors. The second category is amplitude modulations of the electric organ discharge, which are encoded by p-type tuberous receptors. Six multisensory neurons were found that responded to both categories of stimuli. However, when …

Moths Fight Back: Arms Race In The Cloud Forest, Diana Pamela Rivera

Theses

Moths and bats engage in a coevolutionary arm race, where the same signals bats use to find moths are being used by moths to avoid bats. Moths evolve not only behavioral but acoustic responses to avoid predation by bats. This research examines one small component of a complex, multispecies arm race between moths and bats. In this study we found that the moth Amastus hyalina displayed both flight and acoustic responses to ultrasonic stimuli.

In tethered flight the tiger moth Amastus hyalina (Arctiinae) exhibits a complex array of reactions to ultrasonic tones that includes changes in flight and production of …

Determining How Stable Network Oscillations Arise From Neuronal And Synaptic Mechanisms, Diana Martinez

Dissertations

Many animal behaviors involve the generation of rhythmic patterns and movements. These rhythmic patterns are commonly mediated by neural networks that produce an oscillatory activity pattern, where different neurons maintain a relative phase relationship. This thesis examines the relationships between the cellular and synaptic properties that give rise to stable activity in the form of phase maintenance, across different frequencies in a well-suited model system, the pyloric network of the crab Cancer borealis. The pyloric network has endogenously oscillating ‘pacemaker’ neurons that inhibit ‘follower’ neurons, which in turn feed back onto the pacemaker neurons. The focus of this thesis …

Attraction And Risk In Urban Bird Habitats, Megan E. Litwhiler

Dissertations

Urban expansion is an increasing threat to native bird populations. Consequently, maintaining and developing safe urban habitat space is necessary for conservation. Birds living in, or migrating through, urban areas utilize a variety of managed green-spaces such as parks, gardens, college campuses, and cemeteries. In addition to managed habitats, birds may use abandoned property that has been reclaimed by vegetation and associated spontaneous, biological communities. Such urban habitats may provide valuable resources for birds and other wildlife; however, these sites often contain high densities of non-native plants and can be polluted, potentially imparting a greater risk than benefit to the …

The Role Of Electronsensory Signals On The Locomotor Performance Of The Weakly Electric Fish Apteronotus Albifrons, Oswaldo Gil-Guevara

Theses

Animal locomotion performance responds to different ecological factors that shape relevant aspects of behavior. Conspecific signals is one of these factors and operates in a wide range of contexts. In schooling fish, coordinated movement is based on visual or mechanical cues and signals. In contrast, most gymnotiforms and mormyriforms are nocturnal or live in dark waters and use electric signals for social communication. However, the effect of conspecific electric signals on locomotion and group movement is largely unknown.

Apteronotus albifrons is a well-known model in neuroethological studies of signal processing and locomotion control that relies mostly on visual inputs but …

E Pluribus Unum: What Individual Whales Can Tell Us About Enigmatic Species Distribution And Social Organization, Tanya Marie Lubansky

Dissertations

Large whales have historically been difficult to study and many aspects of their ecology remain unknown especially at the long -term population level. The ability to identify individual whales based on natural markings provides the opportunity to track individuals over time and space; this data may offer more insight into the ecology of whales than previously imagined. This study demonstrates use of photo-identification data to model both social structure and habitat selection, minimizing the need for invasive research and greatly increasing the sample size used in such endeavors. A conditional logistic model is written for a 20-year sightings dataset on …