The John J. Pescatello Torchwood Hammock Preserve, comprising 97 ha, is located on Little Torch Key, 24 39” N Latitude, 81 23” Longitude. The preserve was surveyed for vascular plant species in February, 2012, and again in July, 2013. The vascular flora of the preserve consists of 126 species within 86 genera and 45 families. The largest families in the flora were the Poaceae (18), Fabaceae (10), Asteraceae (7), and Rubiaceae (6). The largest genera were Borrichia, Solanum, and Tillandsia, each with three species. Six endangered species and seven threatened species compose 10% of the flora. Five non-native species were identified within the preserve. With little anthropogenic disturbance except at the roadside right-of-way border, the flora here was stable, though hurricane damage might provide fertile habitat for invasive Schinus terebinthefolius and Casurina spp. in the future. The present floristic study of the Pescatello Preserve provides a vascular plant inventory that can be compared with future floristic studies at this site.

The purpose of this study was to determine if a microbial biomarker for successful remediation of the polychlorinated biphenyl (PCB) contamination in the Hudson River could be identified by evaluating the cytoplasmic redox states of microorganisms isolated from the river. Studies have indicated that PCB exposure leads to oxidative stress in bacteria. Water samples were collected from the original dumping sites of PCBs and the following locations (Environmental Protection Agency (EPA) dredged locations are highlighted with year of dredging): Hudson Falls, Fort Edward Dam (2011), Thompson Island Dam (2014), Northumberland Dam (2012), Thomson (2013), Schuylerville Island, Saratoga National Park (2013), Lock 3 in Mechanicville (2015), and Federal Dam in Troy. Samples from Beacon, NY, and the East River at Brooklyn Bridge Park (130 miles downriver from the PCB contaminated sites) were collected as controls. Our evaluation of bacterial diversity at the sites led to the isolation of 33 bacteria, 28 of which were positively identified using a bacterial identification system. An analysis of the NAD⁺ and NADH,H⁺ concentrations and NADH,H⁺:NAD⁺ ratios across the isolated bacteria as a way to quantify cytoplasmic redox stress demonstrated that there was no significant difference in NAD⁺ and NADH,H⁺ concentrations or NADH,H⁺:NAD⁺ ratios between the organisms regardless of site dredging status. However, upon comparing NADH,H⁺:NAD⁺ ratios between matched bacterial isolates from undredged and dredged sites, we determined that the decrease in ratio by the PCB degrading bacterium, Pseudomonas taetrolens, approached significance (p = 0.065) suggesting that its presence at dredged sites may be used as an indicator of successful remediation.

Dendritic cells (DCs) link the innate and adaptive immune response by capturing antigen to present to and activate naïve T cells. Subsets of DCs vary based on protein expression, which allows for their identification. This research focused on total DCs (CD11c⁺), and the conventional DC subsets (cDC1 and cDC2). Corticosterone (CORT), a stress-induce glucocorticoid hormone, reduces DC numbers and alters DC function and subsequent T cell responses. The current study quantifies DC recovery after CORT exposure and demonstrates that the loss of DCs can be prevented. Mice were exposed to exogenous CORT in the drinking water for 24 hours. CORT exposure significantly decreased the numbers of all splenic DCs. Mice were then provided varying recovery times (3, 5, or 10 days) post-CORT exposure. DCs quickly returned to normal levels, and even exceeded the percentages in control untreated mice. Studies have shown that injection of mice with anti-CD40 antibody triggers DC maturation and proliferation. Thus, it was hypothesized that injection of anti-CD40 may prevent the CORT-induced loss of DCs. Mice received two injections of anti-CD40 antibody over two days and were then immediately supplied with CORT. When provided anti-CD40 prior to CORT, the loss of DCs was prevented. These studies contribute to the ongoing exploration of the mechanisms underlying the immunological effects of stress-induced glucocorticoids.

Fecal matter transplants (FMT) are an effective, yet underutilized, treatment for potentially life-threatening Clostridium difficile infections. Following antibiotic treatment, an imbalance between the types of colonic microbiota naturally present in a person's gut may occur, allowing the opportunistic pathogenic bacterium C. difficile to proliferate and reach virulent levels. Despite a 90% success rate, and patient reports of immediate improvement, FMTs are approved only as a last resort due to strict US Food and Drug Administration (FDA) restrictions. This study aimed to compare microbial preservation methods to determine the method with the least detrimental effects on the composition of stool microbes. Fecal matter samples, from dogs, were homogenized with either sterile deionized water or 0.85% NaCl. The homogenized mixtures were then partitioned for immediate DNA extraction or for preservation with or without 25% glycerol prior to -80°C storage. After 3 weeks, and again after 10 months, DNA extraction was performed on stored samples. All extracted DNA was subjected to PCR amplification and sequenced. After pairing and filtering, 88.3% of data were retained. Changes in taxa richness over time for each treatment were not significant; changes in taxonomic composition over time were detected in water only and saline only treatments (p = 0.016, p = 0.049 respectively). The water-glycerol treatment resulted in the least amount of change in taxonomic composition and proportions when compared to the sample prior to preservation. Information gained from this study could be used to further improve FMTs and help fuel FMT related research in hopes of attenuating FDA restrictions.

Zooplankton communities are typically comprised of smaller-bodied species when size-selective fish predators are abundant, but become dominated by large-bodied species when fish predators are scarce. Superiority by larger-bodied grazers over smaller-bodied species in competition for algal resources has been proposed to be the mechanism responsible for this observed pattern. To investigate this mechanism, we performed a laboratory experiment with two freshwater zooplankton species, the larger-bodied Daphnia pulicaria and smaller-bodied D. mendotae, obtained from Square Lake (Washington County, Minnesota). The Daphnia species were grown in monoculture and in combination over a 24-day period to assess the outcome of competition between the two species and their effect on algae cell densities. We hypothesized that the larger-bodied D. pulicaria species would outcompete D. mendotae, and that D. pulicaria would exert greater control on algae levels than would D. mendotae. Results of the experiment strongly supported these hypotheses, and were consistent with findings of a recently completed field study of Square Lake that discovered that terminating the program of stocking rainbow trout (a zooplanktivorous predator) in the lake resulted in D. pulicaria replacing D. mendotae as the dominant Daphnia species and in the reduction of algae levels in the lake's surface waters.

The genus Agalinis (commonly known as the “false foxgloves”) belonging to the family Orobanchaceae, is native to the Western Hemisphere. Approximately 40 species are distributed across temperate North America, and a large group is native to Missouri and the Midwestern United States. Twenty-one species of this genus warrant conservation measures. Our main aims were to understand the migration and diversification of temperate North American Agalinis, as well as focusing on the six species native to the state of Missouri. This study is the first to investigate the evolutionary diversification of this genus in temperate North America. Computer applications including BEAST (Bayesian evolutionary analysis sampling trees) and SDIVA (statistical dispersal vicariance analysis), and secondary calibrations from previous studies were implemented to understand the diversification timings and ancestral areas of this group. Our study points to southeastern United States as the center of diversity and place of origin of the Agalinis in temperate North America, from which they spread to the rest of the United States and even migrated to Canada, around the mid-late Miocene period. We were also able to trace the biogeography of the Missouri natives which diversified between the late Miocene and the Pleistocene period. It may be hypothesized that climatic shifts and increase in seasonality during the mid-late Miocene period was one of the primary causes leading to the migration and diversification of this genus throughout temperate North America.

The existence of a live-chicken processing plant about 20 meters from a water source in Clarksville, Arkansas, raises concerns about bacteria contamination in the water. Over a period of three days, water samples from three different locations (upstream, across from the processing plant, and downstream) and for three different types of water at each location (running, stagnant in the middle, stagnant near bank) were collected in triplicate. Bacterial colonies were grown on 3M Escherichia coli/Coliform Petri-Film to identify and count E. coli, coliforms, and other Gram-negative bacteria. E. coli colonies were isolated and antibiotic resistance assays were performed for Ciprofloxacin and Sulfamethoxazole/Trimethoprim. Coliform and other Gram-negative bacterial counts were higher across and downstream from the chicken processing plant as compared to upstream (p < 0.05). High levels of bacteria are not above EPA markers, but are still alarming for the community. There is no significant difference in E. coli antibiotic resistance among locations, but most colonies analyzed were resistant for one of the antibiotics, and no isolate gave a susceptible result, providing more evidence for the increase in antibiotic resistance in wild strains.

Sea urchins are important sentinel species for marine biodiversity given that they help maintain coral reefs. The sea urchin species Tripneustes ventricosus is among the most abundant pantropical species, found around the world, including in the Caribbean. In Puerto Rico, T. ventricosus live in the intertidal zones less than 30 m deep and showed rapid recovery, observed within 6 months, after Hurricane Maria. Despite their abundance and resilience, very little is known about their embryonic development or morphological characteristics that may shed light into their role in local coral reefs. The purpose of this project was to determine if T. ventricosus collected from a local beach could be used to study echinoid embryonic development. T. ventricosus proved to be easily collected and spawned using common laboratory techniques. Embryonic developmental timetables were similar to other known tropical sea urchin species. It is generally believed that T. ventricosus is important for the health of coral reefs in Puerto Rico, supporting the need for a more thorough understanding of the life cycle, spawning cycles and phylogeography of this species so important to coral reef survival in a changing environment.