• Influence of Climate on Mosquito Abundance

      Haibach, Nicole; Department of Biological Sciences (2016-03)
      During this project one of the most common outdoors pest was observed, the mosquito. They are important to pay attention to due to their ability to transmit diseases and the irritation they are for humans. This project studied the effect of climate factors on mosquito abundance, which will help to predict when mosquitoes will be the most prevalent. Mosquitoes were collected using CDC gravid traps and light traps, which focused on different parts of the female mosquito life cycle. Mosquitoes were collected at 20 different locations in Richmond County, GA between February 2014 and December 2015. This study compared the impacts of different climate factors, such as precipitation amount, humidity, wind speed, and average temperature on the abundance and periodicity of two different species of mosquitoes, Culex quinquefasciatas and Culex salinarius. We found that temperature was positively correlated with the abundance of these species. Additionally, abundance of these species decreased significantly both above and below certain high and low temperature thresholds. This data will help to better predict when mosquitoes will be the most prevalent, which could help control the mosquito population better. Funding Source: Phinizy Center for Water Sciences
    • Synthesis and Characterization of Novel Nanothermometers

      Baumert, Delphine; George, Larsen; Murph, Simona; Department of Chemistry and Physics (2016-03)
      Nanothermometers enable the measurement of local temperatures at nanoscale dimensions (1-100 nm), which can provide insight into many biological and industrial applications. Previously synthesized nanothermometers are similar to molecular beacons, consisting of fluorescently labeled stem-loop DNA strands linked to gold nanoparticles (AuNPs) via a thiol-gold link- age. The principle behind their operation is that the fluorophore is quenched by the nanoparticle due to the self-binding of the stem-loop DNA at low temperatures. As the nanothermometers are heated, the stem-loop unfolds at its characteristic melting point, and as a result, the fluorophore is no longer in the quenching region of the nanoparticle and a dramatic rise in fluores- cence will occur. The temperature response of the nanothermometer can be selected by optimizing the sequence of the DNA strand. Typically, the AuNPs only serve to quench the fluorophores in these types of nanothermometers. However, by anchoring stem-loop DNA to functional nanoparticles, a new type of system is created, one which can provide tailored functionality and also real-time, local temperature information. For example, AuNPs can be used for their catalytic, plasmonic and visible light properties, Fe2O3 nanoparticles can be used for their magnetic and photocatalytic properties, and Pd can be used for catalysis or hydrogen storage. In an effort to create nanothermometers that also possess these multifunctional properties, we have successfully synthesized a variety of nanothermometers supported by a variety of nanoparticles, including Au, Au-Fe2O3, Pd, Pd-Fe2O3, and Au-Pd-Fe2O3 nanoparticles. The obtained nanothermometers are currently being characterized by fluorescence spectroscopy, scanning electron microscopy, UV-Vis spectroscopy, and phase analysis light scattering (PALS). Funding Source: Department of Energy