Changes in environmental conditions, particularly temperature, are known to affect physiological processes such as growth rate and bacterivory in protists. Modifications to these processes can elicit species-specific changes in survival, growth, and reproduction, thereby affecting the planktonic community composition. The field and laboratory experiments that I conduct analyze how the protistan community of Lake Lacawac in the Pocono Mountains will respond to warmer temperature with focus on bacterivorous and mixotrophic species due to their importance in nutrient cycling. This research will provide insight into how changes in global climate may affect freshwater systems and their planktonic inhabitants. The warming of lakes in response to climate change poses a challenge to protists by restrictions in spatial and temporal abundance, as well as decreased survival of certain functional groups. Such shifts in community structure can contribute to a decrease in protistan diversity and overall ecosystem function of freshwater habitats. Examination of community-level shifts in trophic strategy also represents a potential tool to predict some of the projected negative effects of increased water temperature on freshwater systems.
I am working in Temples Department of Biology with Dr. Daphne Georlette and Dr. Frederic Biemar on a study entitled Elucidation of the Role of miR-184 in maintaining the adult nervous system, using Drosophila melanogaster as a model system. Neurological disorders affect over 100 million people worldwide and disproportionately affect adults over fifty years of age; however, the advent of methods of early diagnosis or efficacious treatments is still in its infancy. Our long-term goal is to identify novel factors which may serve as potential biomarkers of neurological disorders and to contribute to a greater understanding of the etiology of neurodegenerative diseases.
The objective of my research is to study the photochemistry of Nitrogen containing heterocyles, specifically 2-pyridone analogs. Pyridone photochemistry has gained significant interest as it can form Beta Lactam and other cyclooctadiene products that could have synthetic significance. In my research, these cyclooctadiene products are formed in one step, by either [4+4] intermolecular or intramolecular photodimerization, containing four stereocenters and functionality at multiple carbon centers. I am interested in manipulating these "cage-like" cyclooctadiene products by opening them up to give stereocontrolled linear compounds. These linear compounds would contain a backbone found in some protease inhibitors. We are also interested in silicon containing compounds including silanediols and the formation of synthtically useful silyl anions.
I am a Ph.D. candidate conducting research in the laboratory of Dr. Mark A. Feitelson. The work in this laboratory aims to better understand the biology of hepatitis B virus, with special emphasis on elucidating the mechanism(s) of pathogenesis associated with the development of chronic liver diseases, including liver cancer. Specifically, I am studying the mechanism by which hepatitis B X antigen (HBx) may participate in epigenetic regulation of gene expression within infected liver cells to contribute to the pathogenesis of chronic liver disease. I am currently working to identify the possible association between HBx and major epigenetic modifiers as well as any role this association may have in the development of hepatocellular carcinoma.
The goals of my research are to develop all Magnesium diboride (MgB2) Josephson junctions for use in superconductive circuits and devices. Superconductive circuits have demonstrated the ability to operate at several hundred GHz with nearly no power consumption compare to current semiconductor circuits. Superconductive devices like, Superconducting Quantum Interference Devices (SQUIDs), are among the most sensitive detectors in the world. MgB2 is a unique two-band superconductor that can allow these superconducting circuits to operate at a higher temperature (~20 K) and at faster speeds (~ 1 THz).
Several groups of tropical and sub-tropical marine invertebrates maintain symbiotic relationships with photosynthetic dinoflagellates (zooxanthellae), and rely on these symbionts for meeting their nutritional requirements. I am interested in how climate change will affect these symbioses. More specifically, I am monitoring several biological processes of zooxanthellae in hospite (within invertebrates) as they are exposed to gradual elevations in water temperature and dissolved carbon dioxide. My goal is to identify some of the physiological and biochemical responses of zooxanthellae to changing environmental conditions that can lead to the breakdown of the symbiosis and mortality of the host.
I work in a deep sea ecology lab at Temple University. I study communities of organisms that are found only at hydrothermal vents and hydrocarbon seeps. These occur at depths so great that the foundation species (tubeworms that create habitat for other animals) of these chemosynthetic communities live in symbiosis with bacteria that get their energy from chemicals flowing from beneath the sea floor instead of sunlight. In my lab I am currently analyzing two distinct communities of tubeworms and associated fauna (all the animals that live on and around them). I am interested in any differences and similarities between these two samples, that were separated by distance (twelve hundred miles) and habitat type (one is from a vent and one is from a seep). I am further studying the communities from the seep site because this particular seep lies on a continental margin that is actively subducting. I want to compare this seep community to others nearby that lie on a more stable margin to determine if it shares more characteristics with those, or with communities from hydrothermal vents. These beautiful and unique deep sea chemosynthetic communities need to be protected and studied further, because not enough is known about how they interact with each other and affect the world around them.
In my research in the Computer Vision field, I have helped develop an automatic marker matching algorithm. Given a sequence containing hundreds of frames, each containing over 30 points, this algorithm can predict the labels of all points in the sequence with just one frame initially labeled. This algorithm has been compared to already existing software such as Cortex, as well as an implementation of the Iterative Closest Point Algorithm. I have also begun work on automatically detecting unintentionally revealed privacy information in image files.
My research is an interdisciplinary field that combines Computer Information Systems with Behavior Analysis. We are currently developing software and tools to help guide therapists in their efforts to reverse the effects of autism. In particular, we are developing a mobile application that utilizes a proven method called Applied Behavior Analysis (ABA) and that will provide better reinforcement techniques in autism therapy and treatment. We are specifically focusing on predicting best reinforcement tasks and best task selection practices for Discrete Trial Training (DTT) and Pivotal Response Training (PRT).
The objective of our research is to develop a new type of ambient mass spectroscopic technique combining laser vaporization and electrospray ionization. The combination of laser vaporization and electrospray ionization allows for the vaporization of sample molecules followed by ionization in the electrospray plume. Using laser electrospray mass spectrometry, LEMS, we have successfully analyzed large biomolecules, explosives, pharmaceuticals, and tissue.
Carbohydrates and glycoconjugates play an essential role in biology and medicine. Understanding of these roles is what I am currently working on with Dr. Rodrigo B. Andrade at Temple University and in collaboration with Dr. Daniel Ratner at the University of Washington Seattle. I synthesize complex carbohydrate scaffolds that are made into microarrays in an attempt to develop technologies to study carbohydrate-protein, -nucleic acid, and -cell interactions. These tools will improve our understanding of the biological roles of carbohydrates and support the development of novel drugs and treatments for cancer and infectious diseases.
My research interests are in the field of inorganic chemistry and biology. I am a PhD candidate working in Dr. Michael Zdilla’s laboratory in the Temple University Chemistry Department. In particular, our group specializes in synthesis and reactivity of biologically inspired metal clusters. My research has two foci: synthesis and characterization of low coordinate Manganese (Mn) clusters; and to design protein scaffolds for the assembly of metalloclusters.
I am currently a graduate student in the Biology Department working in the developmental genetics lab of Dr. Darius Balciunas and Dr. Jorune Balciuniene. Our lab uses the zebrafish as a model system for studying gene function. Using insertional mutagenesis, the lab sets out to generate and characterize gene-trap lines relevant for studying cardiovascular development and regeneration, as well as various aspects of nervous system development. One long-term goal of the lab is to improve the viability of the zebrafish as a model system for genetic study by developing efficient and predictable methods for transgenesis. I am currently working on characterizing a mutant generated in our lab that contains a gene-trap insertion into a gene that is expressed throughout the nervous system. This insertion results in a null allele and the expression of green fluorescent protein (GFP) driven by the endogenous promoter of this gene to visualize its cell-specific expression. As mutations in this highly conserved gene have been implicated in possibly contributing to bipolar disorder in humans, rapid onset dystonia-parkinsonism, and childhood hemiplegia, characterization of this gene includes an array of both molecular and behavioral analyses. Our goal is to show that our mutant is the best current animal model for studying our gene of interest and disorders linked to it, as well as to shed light on possible developmental and maintenance roles on nervous system function.
My work with Dr. Feroze Mohamed at the Temple University Magnetic Resonance Imaging Center is focused on diffusion tensor imaging (DTI) of the spinal cord. DTI is an effective technique for non-invasive in-vivo measurement and quantification of water diffusion in human tissue, and has the potential to be an important diagnostic tool for white matter integrity in the injured spinal cord. In addition to DTI data collection, we are working to address some of the technical challenges of DTI of the spinal cord, including motion artifacts caused by physiological motion, and metal artifacts resulting from the presence of spine stabilization hardware in many subjects with spinal cord injury.
My research focuses on the dynamics of filamentation and its use for impulsive Raman spectroscopy. When a high-powered laser beam passes through a medium, it changes the index of refraction of the material, causing the laser beam to focus. Once a high enough intensity is reached, the medium is ionized, generating a low-density plasma that de-focuses the pulse. The interplay between focusing and defocusing results in an elongated, low-density plasma channel in air called a filament. The intense interaction of the laser beam with the medium in the filament channel changes the spectral and temporal properties of the laser beam, resulting in pulse compression and broadband continuum generation. These properties of the laser beam after filamentation are of interest for many applications, including spectroscopy and high-harmonic generation. My research focuses on the latter and on using the vibrational (Raman) response of the medium to characterize the dynamics of filament formation and propagation. The vibrational response can also be used to characterize the molecular make-up of the medium, which is promising for sensing and detection applications.
My research with Dr. Nancy Pleshko, in the Tissue Imaging & Spectroscopy Lab, focuses on using Fourier Transform Infrared (FTIR) spectroscopy to assess osteoarthritic articular cartilage. FTIR spectroscopy is a nondestructive method capable of determining molecular composition of articular cartilage by evaluation of differences in infrared absorbance frequencies of biomolecules present in samples. Coupling an FTIR spectrometer to an infrared fiber optic probe (IFOP) can allow spectral data to be acquired arthroscopically. My project sets out to validate the use of novel IFOP probes to predict the histological grades of cartilage. Furthermore, my project looks to help identify a sterilization method that will maintain the integrity of the IFOP before translation into the clinical setting where it will be used to evaluate cartilage integrity.
The deliberate or unintentional introduction of invasive species by humans is one of the leading drivers of global biodiversity loss. Thus, understanding invasion dynamics is essential in developing effective management and prevention strategies to mitigate the threat of invasions on our native systems. I am a PhD candidate in Dr. Amy Freestone's laboratory in the Temple University Biology Department, interested in the biotic mechanisms of invasions. My research focuses on predator-prey interactions that facilitate or inhibit invasive species establishment in marine benthic communities. I am also interested in native communities that have the potential to biotically resist invasion, and am examining how this invasion resistance varies with latitude.
Our group's main focus is to understand the mechanism of DNA repair by the blue-light activated enzyme DNA photolyase. We use various spectroscopic techniques to investigate the excited state electronic properties of the catalytic cofactor FAD. I use Stark spectroscopy, a special type of absorption spectroscopy, along with computation methods to determine both the direction and magnitude of the cofactor's excited state dipole moment. This information can suggest possible pathways of electron transfer from the cofactor embedded in photolyase to the damaged DNA during repair.
I am currently investigating nutrient and contaminant transport in subsurface and marine environments as well as the bio-degradation of hydrocarbons, particularly those found in crude and highly weathered oil. Applications of this research includes developing new remediation techniques for oil spills such as the BP Gulf Spill and the Exxon Valdez Oil Spill. These techniques are currently under investigation in Prince William Sound in an effort to remediate the thousands of gallons of oil still present as a result of the spill.
My research interests center on community ecology and invasion biology dynamics. Specifically, I am interested in the relative influence of biotic factors such as predation and competition with invasive species on community assembly. I am also interested in identifying traits or suites of traits that may serve as predictors for invasive species. My previous research has focused on invaders as ecosystem engineers in freshwater systems.
I am interested in the role of endosymbiosis in the evolution of algal protists and their plastids, and am currently investigating what may be an early stage of plastid acquisition. I am studying a dinoflagellate that lacks permanent plastids but acquires unusually long-lived yet temporary plastids from its algal prey. In one set of experiments, I am trying to determine if the dinoflagellate will also retain plastids from other related algal species. In other experiments, I am studying changes over time in the number, structure, and function of retained plastids in dinoflagellates deprived of algal prey. I am also investigating the possible role in plastid maintenance of prey nuclei temporarily retained in a minority of cells.
My research has two foci. The first area is studying cis/trans amide bond isomerization in proline and hydroxyproline. There are several factors involved that are difficult to isolate and characterize in the natural molecules. To address this we have synthesized compounds to isolate the competing factors. These compounds include 2-aza-bicyclo-[2.1.1]hexane based analogs, as well as modified prolines and pyrrolidines. The other focus of my research is in the use of β-methanoproline oligomers as novel molecular scaffolds. This involves both synthesizing and characterizing new β-peptide oligomers, with biologically active short peptides as the end goal.
I am a PhD candidate at the Temple University College of Engineering, working with Dr. Kurosh Darvish at the Temple Biomechanics Laboratory (TBL). The main focus of the research at TBL is to investigate the properties of soft tissues under impact (real life situation examples: car accidents, falls, and sports injuries) and the mechanism of resulting injuries. I specifically have been working on the brain tissue. I have studied the changes of the viscoelastic properties of brain tissue due to injury under different modes of loading, and studied the mechanism of brain injuries in collaboration with the Temple University School of Medicine. I have also worked on several projects on liability of medical devices, namely orthopedic surgery devices and stent grafts. Currently, I am working on developing a new constitutive equation for brain tissue under high-rate multiaxial loading for my PhD dissertation.
I have been working in the experimental neurobiology lab of Dr. Ed Gruberg for the past 4 years. My research project is aimed at the question, “How does a frog see stationary objects?” There’s an old myth still floating around that a frog can’t see things unless they're moving. This simply isn’t true: a motionless frog will spontaneously jump, with perfect accuracy, through a narrow aperture in the walls of its enclosure. No question it can see those walls. It is true, however, that two very different neural circuits are involved in the frog's perception of things that are moving vs. things that are not. The system that processes visual information about moving objects (like prey and threats) has been known in detail for a long time. The system that handles the stationary visual environment of the frog, on the other hand, remains largely mysterious. In our lab, we have a hypothesis about the location of the “stationary-object processing center” in the frog's brain, and my research is concerned with testing this hypothesis. We use a combination of techniques to approach the question from several different angles: (1) anatomical tracings (with cellular stains) of the connections to and from the candidate brain areas; (2) electrophysiological recordings (using microelectrodes) from the brain of awake frogs: the frogs are shown visual stimuli representing stationary objects while we "listen in" on their neuronal activity; and (3) behavioral tests, such as "running" a frog through an obstacle course, before and after certain parts of its brain have been disconnected. Elucidating the neural circuitry of the frog's visual system can shed light on principles of vertebrate vision in general principles which relate to larger questions about visual processing, even in animals as different from frogs as humans, who also have separate systems for representing moving vs. stationary objects.
The goal of my research is to construct and test a comprehensive model for the interaction of therapeutic-intensity millimeter wave radiation with the cell membrane proteins that regulate the flow of ions into cells. Millimeter wave therapy is a form of medicine practiced largely in Eastern Europe and the republics of the former Soviet Union. Its acceptance in Western medicine has been delayed due to a lack of quantitative explanation of how a form of radiation absorbed by the skin can affect internal organs remote to the site of exposure. A model such as I propose would be a valuable step in explaining this process.
While conspicuous differences are observed between species, differences between males and females within a particular species can also be elaborate. These differences, at both the phenotypic and molecular levels, may provide potential primary targets of selection. As a third year student in the laboratory of Dr. Rob J. Kulathinal in Temple's Department of Biology, my broad research interests lie in understanding the role of selection on sex- and reproductive-related genes in driving species level divergence. Specifically, I am interested in understanding how selection on these traits acts differently in nontraditional models of speciation such as founder effects on novel island environments. Using multiple species groups including Drosophila and primates, I use bioinformatic and genomic tools to identify genes of interest and characterize their role in driving genetic divergence.
I work with Dr. Ann Valentine in Temple University's Department of Chemistry in the area of bioinorganic chemistry. Living organisms require metal ions for many biological processes. Too little or too much of many metal ions like iron can be harmful to health. Nature has developed complex mechanisms to deal with this problem. One of those mechanisms involves the use of a transferrin protein that binds iron(III) in the blood and transports it into cells for use and/or storage. My work focuses on a transferrin from the sea squirt Ciona intestinallis called nicatransferrin. We believe that we can learn from the sea squirt how the ability to handle a difficult metal like iron evolved.