TRPA1 Mediates Mechanical Currents in the Plasma Membrane of Mouse Sensory Neurons

Mechanosensitive channels serve as essential sensors for cells to interact with their environment. The identity of mechanosensitive channels that underlie somatosensory touch transduction is still a mystery. One promising mechanotransduction candidate is the Transient Receptor Potential Ankyrin 1 (TRPA1) ion channel. To determine the role of TRPA1 in the generation of mechanically-sensitive currents, we used dorsal root ganglion (DRG) neuron cultures from adult mice and applied rapid focal mechanical stimulation (indentation) to the soma membrane. Small neurons (diameter <27 µm) were studied because TRPA1 is functionally present in these neurons which largely give rise to C-fiber afferents in vivo. Small neurons were classified by isolectin B4 binding

Nociceptors: a phylogenetic view

The ability to react to environmental change is crucial for the survival of an organism and an essential prerequisite is the capacity to detect and respond to aversive stimuli. The importance of having an inbuilt “detect and protect” system is illustrated by the fact that most animals have dedicated sensory afferents which respond to noxious stimuli called nociceptors. Should injury occur there is often sensitization, whereby increased nociceptor sensitivity and/or plasticity of nociceptor-related neural circuits acts as a protection mechanism for the afflicted body part. Studying nociception and nociceptors in different model organisms has demonstrated that there are similarities from invertebrates right through to humans. The development of technology to genetically manipulate organisms, especially mice, has led to an understanding of some of the key molecular players in nociceptor function. This review will focus on what is known about nociceptors throughout the Animalia kingdom and what similarities exist across phyla; especially at the molecular level of ion channels

Aggregation Mechanisms and Morphology of Engineered Nanomaterials Bridging the Gap Between Academia and Society

The primary goals of this doctoral research were to investigate aqueous solution parameters that may affect the aggregation behavior of engineered nanomaterials (ENMs), increase the analytical capacity of the colloidal research community, and explore ways in which scientists and engineers can collaborate across disciplines in ways that make individual efforts more robust and more amenable to positive societal contributions. Studies with ENMs were conducted with materials ranging from established, widespread titanium dioxide, to unique, niche graphene oxide and molybdenum disulfide, to emerging, nascent few-layered black phosphorus. The effects of environmentally relevant parameters (i.e., pH, ionic strength, cation valence, extracellular polymeric substances, surfactants, and coagulant) on the electrokinetic properties, aggregation rates, and/or aggregation morphology of the ENMs were investigated. The following valuable insights were obtained from this dissertation research. The 2D black phosphorus ENMs investigated were found to be colloidally stable in environmental conditions. This insight could be used to further develop BP towards future biomedical and environmental applications. In addition, this investigation demonstrated the validity of using traditional colloidal characterization techniques on non-spherical, two-dimensional ENMs. Results from this work could lead to further research into the stability of other 2D ENMs, improving the collective scientific knowledge, and leading to further, novel applications of these versatile ENMs. A further aim of this research was to identify effects of specific environmental parameters on titanium dioxide nanoparticles. The resultant information can be used to better predict the fate and transport of this common ENM in complex environments. The final objective of this doctoral research, to lessen the divide between the academic research community and policymakers, was achieved by applying technical expertise and scientific principles to two distinct challenges; the correlation of personality to drinking water preferences and the synthesis of best practices for state-level water data management. This dissertation provides critical understanding of fundamental aggregation behavior of various ENMs and demonstrates the value of extending the tools of the scientific enterprise across disciplinary boundaries and beyond the ivory tower of academia

Aggregation Mechanisms and Morphology of Engineered Nanomaterials Bridging the Gap Between Academia and Society

The primary goals of this doctoral research were to investigate aqueous solution parameters that may affect the aggregation behavior of engineered nanomaterials (ENMs), increase the analytical capacity of the colloidal research community, and explore ways in which scientists and engineers can collaborate across disciplines in ways that make individual efforts more robust and more amenable to positive societal contributions. Studies with ENMs were conducted with materials ranging from established, widespread titanium dioxide, to unique, niche graphene oxide and molybdenum disulfide, to emerging, nascent few-layered black phosphorus. The effects of environmentally relevant parameters (i.e., pH, ionic strength, cation valence, extracellular polymeric substances, surfactants, and coagulant) on the electrokinetic properties, aggregation rates, and/or aggregation morphology of the ENMs were investigated. The following valuable insights were obtained from this dissertation research. The 2D black phosphorus ENMs investigated were found to be colloidally stable in environmental conditions. This insight could be used to further develop BP towards future biomedical and environmental applications. In addition, this investigation demonstrated the validity of using traditional colloidal characterization techniques on non-spherical, two-dimensional ENMs. Results from this work could lead to further research into the stability of other 2D ENMs, improving the collective scientific knowledge, and leading to further, novel applications of these versatile ENMs. A further aim of this research was to identify effects of specific environmental parameters on titanium dioxide nanoparticles. The resultant information can be used to better predict the fate and transport of this common ENM in complex environments. The final objective of this doctoral research, to lessen the divide between the academic research community and policymakers, was achieved by applying technical expertise and scientific principles to two distinct challenges; the correlation of personality to drinking water preferences and the synthesis of best practices for state-level water data management. This dissertation provides critical understanding of fundamental aggregation behavior of various ENMs and demonstrates the value of extending the tools of the scientific enterprise across disciplinary boundaries and beyond the ivory tower of academia

Boons or boondoggles: An assessment of the Salton Sea water importation options

Several ways to address the looming ecological disaster that is the Salton Sea have been proposed — including water importation. Here we considered two options: importing ocean water from the Sea of Cortés and leasing water from agricultural users in the Imperial Valley. We estimated the monetary costs for importing Sea of Cortés water to the Salton Sea and compared that with the costs of transferring water from agricultural users to the Salton Sea. We found that leasing water from agriculture would be substantially cheaper than ocean water imports. Additionally, all the infrastructure for leasing water from growers exists, which means water transfers could begin immediately. That is important given the present and increasing environmental and human health damages that are occurring at the Salton Sea