Invasive plant species significantly impact native ecosystems by outcompeting indigenous flora, reducing biodiversity, and disrupting the delicate ecological equilibrium. In collaboration with the Fort Worth Botanic Garden, this research study evaluated the efficacy of utilizing sheep and goats as a sustainable grazing strategy to mitigate invasive plant species within the garden.

Vegetation analyses, specifically vegetative cover and species richness, of pre- and post-grazing indicated an initial decline in plant species richness. However, based on prior studies, plant succession and resilience are anticipated to rebound in the grazed areas over time (Booth & Skelton, 2009; Rathfon et al., 2021). The research findings also indicated environmental and operational benefits, including reduced labor costs, minimized chemical inputs, decreased noise pollution, and mimicked historical ecological processes that have been found to improve soil health and biodiversity. The findings from this research emphasize the targeted use of livestock grazing as a sustainable land management practice. This case study highlights the benefits of integrating controlled livestock grazing into public garden maintenance protocols. Furthermore, this research contributes to the existing literature regarding sustainable land management and the role of livestock in controlling invasive species and restoring ecosystems.

References

Booth, A. L., & Skelton, N. W. (2009). The use of domestic goats and vinegar as municipal weed control alternatives. Environmental Practice, 11(1), 3-16. DOI:10.1017/S1466046609090012

Rathfon, R. A., Greenler, S. M., & Jenkins, M. A. (2021). Effects of prescribed grazing by goats on non‐native invasive shrubs and native plant species in a mixed‐hardwood forest. Restoration Ecology, 29(4).

https://doi.org/10.1111/rec.13361

Mercury (Hg) emitted in temperate and tropical regions can be transported to the Arctic where it is disproportionately deposited across the landscape. In aquatic systems, inorganic forms of Hg can be methylated to the toxic and bioaccumulative species, methylmercury (MeHg). In temperate zones, riparian spiders that specialize in consuming adult insects emerging from aquatic systems (e.g., Araneidae and Tetragnathidae) accumulate high concentrations of MeHg and have been used as sentinels of MeHg contamination. In addition, these taxa frequently accumulate concentrations of MeHg that may pose a risk to arachnivorous songbirds. Although these taxa are useful sentinels in risk assessment studies in the temperate zone, they are not present in the High Arctic. The purpose of the present study was to assess the potential of a generalist spider species, the Arctic wolf spider (Pardosa glacialis), to serve as a sentinel of Hg pollution in the Arctic. In summer 2022, we collected 1460 wolf spiders and 8090 emergent aquatic insects (Chironomidae) from six ponds in Northwest Greenland (centered around 76.5° N, 68.8° W). Spiders and insects were composited by body size and collection site. Hg concentrations for spiders and insects ranged from 230 - 1100 ng/g dry weight (dw) and 75 - 297 ng/g dw, respectively. Spider Hg concentrations were strongly correlated with insect Hg concentrations (R2 = 0.83), suggesting that wolf spiders can be used as sentinels of Hg contamination in Arctic lentic systems and had Hg concentrations that exceeded risk thresholds for arachnivorous songbirds.

Bacteriophages, the most abundant biological entities on Earth, specifically infect bacteria. These viruses initiate the lytic cycle, hijacking the cellular machinery of their bacterial hosts to replicate, which ultimately leads to the host's destruction. Phage therapy has shown promising results in treating antibiotic-resistant infections, though clinical trials are ongoing to fully establish its safety and efficacy. Identifying suitable phages is crucial in developing successful therapy due to the specificity of bacteriophage-host interactions.
Our study refined methods for isolating and studying bacteriophages against Enterobacter aerogenes, a critical ESKAPE pathogen contributing to antibiotic resistance. We evaluated two isolation techniques: the overnight enrichment assay and direct isolation via the whole plate spotting assay. Our comparison found an advantage of the direct isolation method—it not only matched the efficacy of the overnight enrichment but surpassed it by offering accelerated results and minimizing resource utilization. A key refinement for purification was the incorporation of calcium chloride into the soft agar, which markedly enhanced plaque clarity and visibility. Moreover, our exploration of DNA extraction techniques revealed the superiority of zinc chloride precipitation over commercial kits, with the former delivering higher DNA yield and purity.
We isolated three phages, K-1, BB-1, and M-1, effective against E. aerogenes. Noteworthy, phage BB-1 exhibited a rapid lytic cycle, clearing plates in under 10 hours. Future research will focus on examining their infectivity across Enterobacter strains, lysis of host cells, and absorption rates. We will also analyze their genome sequences to determine their novelty and potential for addressing antibiotic resistance.

The presence of Reactive Oxidative Species (ROS) in the brain have been linked to the etiology of Alzheimer’s disease and neurodegeneration. In this project, novel antioxidant Indole derivative drugs were tested on BV-2 microglial cells using RT-qPCR to assess their ability to activate antioxidant gene expression. Nuclear factor erythroid 2–related factor 2 (Nrf2) is a gene transcription factor that is activated by oxidative stress and binds to a sequence called the Antioxidant Response Element (ARE), a region upstream of the DNA promoter sequence. Nrf2 activates transcription of antioxidative genes. Based on theoretical docking studies, we hypothesize that the novel compounds will disrupt the interaction between Nrf2 and its inhibitor KEAP, releasing Nrf-2 and enabling it to translocate to the nucleus. The novel antioxidant drugs should either increase the transcription of Nrf2-activated genes or reduce overall levels of antioxidative stress within cells. We tested for antioxidant properties by measuring Hemeoxygenase-1 (HO-1) and Nrf2 mRNA levels in BV-2 cells in the presence of these compounds.

Estrogen receptor alpha (ERα) and BRCA1 play an important role in the development of breast cancer, and multiple pathways link these two proteins together. Previous studies have identified the ligand binding domain (LBD) of ERα and residues 1 through 258 of BRCA1 as important in the direct physical interaction between these two proteins. This study aimed to characterize the binding kinetics of this interaction in the presence and absence of 17β-estradiol (estrogen) with a shortened BRCA1 construct (residues 177-258); however, binding between ERα LBD and this BRCA1 construct could not be detected through fluorescence emission spectroscopy or isothermal titration calorimetry (ITC). Synthesizing ERα LBD presented challenges with low yield, so the purification protocol was refined to cool bacterial cultures at an OD600 of 0.2 during growth and add dithiothreitol during lysis for improved yield. A 24% decrease in fluorescence intensity upon addition of estrogen to ERα LBD confirmed the ligand-binding functionality of the protein. Additionally, Stern-Volmer studies verified that the estrogen binding site on ERα LBD is located in close vicinity to the tryptophan residues in the protein since fluorescence quenching was more efficient in the absence of estrogen. Finally, factors contributing to the absence of ERα-BRCA1 binding are discussed, including the length of the BRCA1 construct used or the potential necessity of an additional protein, BARD1.