91��Ƶ

2022 Syposium Winners

First Place: Chemistry

As Simple as Possible, but no Simpler: Reduced Models of the Bromite-Iodide Clock Reaction

Citta, Richard; Olsen, Robert

Clock reactions are kinetic phenomena characterized by the sudden appearance or disappearance of a substance after a well-defined period of time. In a large family of these reactions, clock behavior is visualized through an intensely blue solution becoming abruptly colorless as iodine disappears. A detailed mechanistic understanding of clock reactions lagged their discovery by about a century. Today, we can apply modern techniques to further our understanding of their complex nature. We have reinvestigated a mechanism of the bromite-iodide reaction made up of 15 species and 22 reactions. The bromite-iodide reaction is a subsystem of the bromate-iodide reaction, a clock reaction whose rate law is determined in a Chemistry IV laboratory experiment. We take a computational approach to simplifying the mechanism while maintaining clock behavior over a range of conditions. We have developed several reduced models via sensitivity analysis by eliminating redundant species, finding that clock behavior can be maintained when BrO−, IO−, and HOIO are individually removed from the model. Clock behavior is sustained, albeit over a somewhat narrower range of conditions, when combinations of these species are removed. Notwithstanding this narrower range, we have several simplified mechanisms in hand and will proceed to identify the most important reactions through rate sensitivity analysis.

Second Place: Biology and BCMB

The use of eDNA to Characterize Fish Populations in Marine Ecosystems

Aboagye, Marilyn; Bukhari, Nidaa; Patel, Janvi; Sylvestre, Keith; Norton, Emma; Stone, Jasmine; Harmer Luke, Tara

This project uses environmental DNA (eDNA) technology to identify various commercially and recreationally important fish populations from local marine and estuarine ecosystems. This technique results in significantly less disturbance to the aquatic environment when compared to traditional techniques like using nets and trawls to assess the population of fish inhabiting various ecosystems. Water samples were collected from several locations in and around the southern New Jersey coast, and whole genomic DNA was extracted from each sample.  eDNA was PCR amplified using a variety of primers that target regions of the mitochondrial DNA from animal samples, in order to evaluate the effectiveness of each primer set. This work provides a foundation for further analysis of these samples using Next Generation Sequencing techniques

Third Place: Biology

Snakes outperform turtles and a crocodilian on functional assays of innate immune performance 

Tan, Xin Rou “Natalie”

Disease is one of the primary threats to reptile populations, leaving them imperiled globally. However, modern immune research on these ectotherms has lagged behind endothermic birds and mammals. This imbalance leaves conservation biologists to act without a full understanding of reptile host-pathogen dynamics. Innate immunity involves cellular and acellular responses, including natural antibodies (NAbs) and the serum complement cascade. The acellular innate immune system is responsible for eliciting a nonspecific, fast-acting response against microbial infections. The goal of this experiment was to examine interclade variation in acellular innate immune function amongst three major extant reptile clades. Specifically, we characterized innate immune performance in two Squamates (Nerodia sipedon and Sistrurus miliarius), two Testudines (Chrysemys picta and Pseudemys rubriventris), and a Crocodilian (Alligator mississippiensis). We hypothesized that immune performance would vary among groups and reflect phylogenetic relationships. We employed immune performance assays which challenged individuals’ plasma against a gram-negative bacterium, E. coli, and mammalian erythrocytes in vitro. Bactericidal assays provide an assessment of complement mediated-lysis via the classical and lectin-mediated pathways. Erythrocyte hemolysis assesses complement-mediated cell lysis via the classical and alternative assays, and erythrocyte agglutination reflects the activity of NAbs. Complement performance of squamates was significantly better than turtles and crocodilians, which did not perform differently from each other. Our results support the hypothesis that the major reptile clades differ in complement performance and that differences may reflect broad phylogenic relationships among clades, therefore, highlighting the need for further exploring of interclade variation in immune function among reptiles.

Honorable Mention: BCMB and Biology

Phylogenetic Analysis of the Zona Pellucida Protein Complex and Zona Pellucida 3 (ZP3) in Vertebrates

Metzler, Matthew; Barbato, Guy F.

The zona pellucida (ZP) complex contains glycoproteins which are utilized in the formation of the “coat” surrounding oocytes. ZP glycoproteins have been shown to be involved in early fertilization events, as well as early embryologic development. The ZP3 gene codes for the predominant protein in the complex that surrounds the mammalian oocyte and plays a pivotal role in fertilization by mediating sperm binding in a species-specific manner, inducing the acrosome reaction, preventing polyspermy and protecting the embryo prior to implantation. Homology of the human ZP complex was examined and the evolutionary history of the ZP3 amongst vertebrates was investigated. ENSEMBL, MEGA-X, WebLogo, and UniProt aided in the visual representation of the homology and evolutionary history of the amino acid sequences within each vertebrates’ ZP3 alignment. High levels of evolutionary homology were seen amongst humans, other primates, and several classes of mammals. Radial phylogenetic trees were utilized to exhibit high conservation of ZP3 sequences amongst these groups as well as low conservativity amongst teleosts. The evolutionary conservation throughout vertebrates has reaffirmed the necessity and importance of the ZP3 in fertilization as the primary, although not exclusive, sperm receptor. As a key protein in reproduction, mutations in the gene may have distinct evolutionary disadvantages. Some vertebrates have acquired due to mutation, specifically indels,  in the gene causing poor oocyte fertilization, small progeny numbers, and longer gestation periods.

Honorable Mention: Geology

Salt Marsh Sediment Accumulation Over a Small Spatial Area

Sarah Kelly

Salt marshes depend on sediment deposition and accumulation in order to survive through times of sea level increase. Sediment deposition in tidal salt marshes is well studied, but research typically focuses on larger areas, which could be less accurate for an entire mash surface. The goal of this research was to determine the spatial variability of sediment deposition and accumulation in a New Jersey salt marsh over a very small area. Sediment traps were placed in the mash at increments of 5 and 10 meters ranging over a 2800m2 squared area. Traps were visited daily, weekly, and at the end of the month to collect sediment, which was then dried and weighed. Results will discuss the correlations of sediment deposition in relation to time, air pressure, water level, and weather. Discovering how the sediment accumulation varies in the small area is important as it allows us to assess the precision on previously published sediment accumulation data.

2021 Virtual NAMS Symposium

Congratulations to our finalists and to everyone who worked so hard to complete their projects under extraordinarily difficult conditions this past year. 

2019 Symposium Winners

First Place: Biology

Analysis of Soil Bacteria for Production of Antibiotics

Daniel Stoyko, Brian Neff, Vincent Anelle, Ellis Kirk, and Karen York

Due to the rise of antibiotic resistant bacterial pathogens, the need to discover new antibiotics has never been greater. One approach to the discovery of new antibiotics is through testing soil bacteria for the production of antimicrobial compounds. A typical 10 gram soil sample can contain up to 2 billion bacteria, each producing hundreds of different organic compounds. Considering that most of the known antibiotics are produced by soil bacteria, some of these compounds could have antimicrobial activity. In this study, soil bacteria from the New Jersey Pine Barrens were isolated, cultured, and screened against non-pathogenic bacteria closely related to common pathogens. Organic compounds were extracted from these soil bacteria and subsequently characterized using gas chromatography-mass spectroscopy (GC-MS). Of the compounds in the extract, some are known for their antibiotic activity (e.g. phenazine). The bacteria were identified by DNA sequencing of the 16S ribosomal RNA gene. Preliminary sequencing results suggest some belong to the genus Burkholderia. The following study improves our knowledge of antibiotics produced by soil bacteria. In addition, this study offers novel compounds with possible antibiotic activity.

Second Place: Biology

Analysis of double-stranded DNA break repair in haploid Saccharomyces cerevisiae under spaceflight conditions

Matthew Elko, Joseph Romanowski, and Daniel Stoyko

Due to the advancement of space age, all spaceflight-associated health risks should be studied in detail. Mistakes in double-stranded DNA break (DSBs) repair can lead to carcinogenesis. Previous studies reported contradictory results regarding the effect of microgravity on DSB repair. Cells have two major mechanisms that repair DSBs: homologous recombination (HR) and non-homologous end joining (NHEJ). HR requires a second, good copy of the damaged DNA for repair, while NHEJ adheres two DNA ends together. The goal of this experiment is to determine how spaceflight impacts NHEJ. To accomplish this goal, we will use the budding yeast Saccharomyces cerevisiae as an experimental model. Yeast have several advantages for this line of investigation: 1) Their NHEJ repair mechanisms are well conserved with humans; 2) Their fast proliferation rate generates sufficient material for cellular and molecular analyses; 3) Yeast can live as either diploids or haploids; haploids must exclusively use NHEJ to repair DSBs; 4) DNA damaging agents have been well-studied in this model. Using the confines of a NanoRacks MiniLab, we have engineered an experimental system which will expose proliferating haploid yeast to bleomycin, a DNA damaging agent. Preliminary experiments have identified an optimal bleomycin concentration (1-5 μg/mL) and a sufficient cell density (2.5 x 106 cells/mL). Using these parameters, we will measure NHEJ in both an experimental sample sent to the International Space Station and an Earth control. The results of these analyses will be crucial in forwarding our understanding of NHEJ in space.

Third Place: Marine Science

Tidal variability of estuarine circulation in Little Egg Inlet

Nicole Ertle and Jaclynne Polcino

Characterizing estuarine circulation is important for understanding larval dispersal, sediment transport and water quality. Estuarine circulation varies with buoyancy inputs, mixing from winds and tides, and changes in bathymetry. This study aimed to quantify momentum balances with changes in the tide in Little Egg Inlet, New Jersey, a major connection point between coastal bays and the Atlantic Ocean. During a 14-hour survey in Little Egg Inlet, an Acoustic Doppler Current Profiler (ADCP) was used to collect velocity data along set transects and a Sontek CastAway CTD was used to collect density profiles at several stations. Results presented here pertain to the Outer Inlet transect which spans from Little Beach (Pullen Island) to Holgate. Velocity data were used to determine vertical shear, and vertical density gradients were used to determine the buoyancy frequency. The Richardson number, a non-dimensional number that characterizes water column stability, was calculated from buoyancy frequency and vertical shear. Over the tide cycle there was variability in the tendency for the water column to go from turbulent mixing during the flood tide to slightly stratified conditions during the ebb tide. Overall net volume transport was landward (573.44 m3 s-1), and varied laterally across the inlet. The results add to our collective understanding of estuary-ocean exchange in well-mixed estuaries and can inform development of hydrodynamic models of the study area.

Honorable Mention: Biology

mTORC1 Activation Alters Neural Stem Cell Fate

Katie Nolan and Nicole DeSimone

In the postnatal brain, the subventricular zone (SVZ) is a niche that maintains neural stem cells and fosters ongoing neurogenesis. Previous studies have shown that neural stem cells in different regions of the SVZ are primed to produce specific types. For example, neural stem cells in the dorsal SVZ preferentially produce TH+ neurons. We examined whether neural stem cells in these areas differ in gene expression. RNA-Seq analysis demonstrated that Pax6 is enriched in dorsal neural stem cells, whereas Nkx2.1 is enriched ventrally. Immunostaining of the SVZ illustrates that Pax6 is restricted to dorsal regions while the mRNA is not. Driving protein translation by activating mTORC1 increased the protein expression of Pax6 and reduced Nkx2.1 expression in vitro. Additionally, mTORC1 activation can increase the number of Pax6+ cells in the SVZ. Taken together, our data suggest that terminal fates of neural stem cells can be modulated by protein translation control.

Honorable Mention: Chemistry

Synthesis and characterization of nickel and ruthenium complexes of primary amido-​functionalized N-​heterocyclic carbene ligands and evaluation of their catalytic activity for transfer hydrogenation

Tiffany Roach, Michelle Schmitza, Valkyrie Leacha, Dangkhoa Voa, Josef DeMarioa, Marcus Millera, Benny Chanb, and Steven Kalman

New nickel complexes of primary amido-​functionalized N-​heterocyclic carbene ligands have been synthesized, characterized, and evaluated for their catalytic activity for transfer hydrogenation, which is the addition of hydrogen across a π-bond using a dihydrogen surrogate. The nickel complexes show moderate catalytic activity for base-​free transfer hydrogenation of ketones under aerobic conditions. Synthesis of half-​sandwich ruthenium complexes featuring these ligands has also been explored. Current work is focused on studying the scope of the catalytic reactions with the nickel complexes, modifying the nickel catalysts for increased activity, and improving the synthesis of the ruthenium complexes. Once the ruthenium complexes have been successfully synthesized, they will be assessed as catalysts for base-​free transfer hydrogenation in air.