Investigators affiliated with the CCS are involved in several multidisciplinary research projects in areas of mathematical biology, fluid dynamics, molecular dynamics, epidemiology, biosensors, economics, and more.
Faculty: Diane Blake, Tom Bishop, Hank Ashbaugh, Don Gaver, Lisa Fauci, Ricardo Cortez
Postdoctoral researcher: Tony Kwan
Student: Kate Hamlington
A biosensor in the traditional sense is defined as a bioanalytical device incorporating a biological material (e.g., tissue, microorganisms, organelles, cell receptors, enzymes, antibodies, nucleic acids, etc.), intimately associated with or integrated within a physicochemical transducer or transducing microsystem that may be optical, electrochemical, thermometric, piezoelectric or magnetic. The traditional goal of a biosensor is to produce either discrete or continuous digital electronic signals, which are proportional to a single analyte or a related group of analytes. From a diagnostic or prognostic perspective, biosensorss provide access to a wealth of molecular information.
Immunosensors are low cost platforms for disease diagnosis, population screening, and environmental monitoring. Because they can provide real-time information about the presence of biological or chemical agents, immunosensors are an important component in our nation’s fight against terrorism. These sensors will link the recognition of a pollutant, toxin or drug by an antibody to the activation of an enzyme. The enzyme, once activated, will subsequently generate a signal that can be detected as a change in electrical current. This project represents an interdisciplinary research effort that includes antibody structure/function studies, molecular dynamics simulations of antibody structure, enzyme reactivation kinetics, electrochemical analysis, the development of predictive microfluidic-transport models that predict fluid transport, and micromanufacturing of miniaturized devices.
Epidemiology: Ivo Foppa, Ricardo Cortez, Angela Gallegos (Occidental)
Mathematical models of West Nile Virus typically assume a fixed biting rate of mosquitoes and 'frequency dependence' of transmission, i.e. transmission intensity depends linearly on the mosquito--to--host ratio; however, both premises have little empirical support.
We address the transmission dynamics of WNV by challenging the assumption of 'frequency dependence' and characterizing the relationship between host abundance/host distribution and feeding rate/feeding density of mosquitoes. In particular, we are interested in revealing the dependence of host density and mosquito--borne transmission dynamics. We hypothesize that when a fixed number of mosquitoes are released in the presence of a group of caged birds, the number of blood-fed mosquitoes will not change with the number of birds (invariant feeding rate) and that in the presence of two sets of caged birds, the mosquitoes will feed in the location with the higher bird density, but that the feeding density per bird will be lower there (frequency dependent feeding density). Additionally, we expect that if mosquitoes are released in the proximity of a one of the cages, the mosquitoes will feed near the point of release independent of the local bird density (site fidelity).
Ecology: Jeff Chambers
Great strides forward in understanding ecosystem response to a changing planet are possible with a close coupling of field ecology, remote sensing and computational modeling. However, few research investigations take such a thoroughly integrative approach, with most groups focusing on one or at most two of these research areas. We are developing an approach for studying ecosystem response to disturbance that comprehensively integrates these three areas, resulting in two nationally competitive funded proposals from NASA’s Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) and DOE-NICCR. Three overall questions motivate the research: (1) How do forest disturbance and recovery processes impact landscape carbon balance and greenhouse gas feedback mechanisms with the atmosphere? (2) How does the land use source of atmospheric CO2 in tropical forests compare with an old-growth carbon sink? (3) Are changes in disturbance intensity and frequency driving shifts in forest tree species composition and opportunities for invasive species? This project addresses these important questions.