Interaction of the parasitic angiosperm {\it Cassytha filiformis\/} L. (Lauraceae) with the exotic {\it Schinus terebinthifolius\/} Raddi (Anacardiaceae) in southern Florida

Brazilian pepper (Schinus terebinthifolius) is an exotic shrub or small tree that has become well established as an invasive and highly competitive species through much of southern Florida. Love vine (Cassytha filiformis), a native parasitic plant, was noted parasitizing Brazilian pepper, apparently affecting its health. The objective of this study was to investigate the nature of this parasitic interaction in southern Florida. Brazilian pepper populations were studied to determine whether parasitism by love vine may affect growth and reproduction. Anatomical studies of love vine parasitizing Brazilian pepper determined physical aspects of the parasitic interaction at the cell and tissue level. Physiological aspects of this interaction were investigated to help describe love vine resource acquisition as a parasite on host Brazilian pepper plants, and as an autotrophic plant. An investigation of ecological aspects of this parasitic interaction was done to determine whether physical or biological aspects of habitats may contribute to love vine parasitism on Brazilian pepper. These studies indicated that: (1) parasitism by love vine significantly decreased growth and reproduction of Brazilian pepper plants; (2) anatomical and physiological investigations indicated that love vine was primarily a xylem parasite on Brazilian pepper, but that some assimilated carbon nutrients may also be acquired from the host; (3) love vine is autotrophic (i.e., hemiparasitic), but is totally dependent on its host for necessary resources; (4) the occurrence of love vine parasitism on Brazilian pepper is mediated by physical characters of the biological community. ^

Ecosystem structure in disturbed and restored subtropical seagrass meadows

Shallow seagrass ecosystems frequently experience physical disturbance from vessel groundings. Specific restoration methods that modify physical, chemical, and biological aspects of disturbances are used to accelerate recovery. This study evaluated loss and recovery of ecosystem structure in disturbed seagrass meadows through plant and soil properties used as proxies for primary and secondary production, habitat quality, benthic metabolism, remineralization, and nutrient storage and exchange. The efficacy of common seagrass restoration techniques in accelerating recovery was also assessed. Beyond removal of macrophyte biomass, disturbance to seagrass sediments resulted in loss of organic matter and stored nutrients, and altered microbial and infaunal communities. Evidence of the effectiveness of restoration actions was variable. Fill placement prevented additional erosion, but the resulting sediment matrix had different physical properties, low organic matter content and nutrient pools, reduced benthic metabolism, and less primary and secondary production relative to the undisturbed ecosystem. Fertilization was effective in increasing nitrogen and phosphorus availability in the sediments, but concurrent enhancement of seagrass production was not detected. Seagrass herbivores removed substantial seagrass biomass via direct grazing, suggesting that leaf loss to seagrass herbivores is a spatially variable but critically important determinant of seagrass transplanting success. Convergence of plant and sediment response variables with levels in undisturbed seagrass meadows was not detected via natural recovery of disturbed sites, or through filling and fertilizing restoration sites. However, several indicators of ecosystem development related to primary production and nutrient accumulation suggest that early stages of ecosystem development have begun at these sites. This research suggests that vessel grounding disturbances in seagrass ecosystems create more complex and persistent resource losses than previously understood by resource managers. While the mechanics of implementing common seagrass restoration actions have been successfully developed by the restoration community, expectations of consistent or rapid recovery trajectories following restoration remain elusive.

Interaction of the parasitic angiosperm cassytha filiformis L. (Lauraceae) with the exotic schinus terebinthifolius RADDI (Anacardiaceae) in southern Florida

Brazilian pepper (Schinus terebinthifolius) is an exotic shrub or small tree that has become well established as an invasive and highly competitive species through much of southern Florida. Love vine (Cassytha filiformis), a native parasitic plant, was noted parasitizing Brazilian pepper, apparently affecting its health. The objective of this study was to investigate the nature of this parasitic interaction in southern Florida. Brazilian pepper populations were studied to determine whether parasitism by love vine may affect growth and reproduction. Anatomical studies of love vine parasitizing Brazilian pepper determined physical aspects of the parasitic interaction at the cell and tissue level. Physiological aspects of this interaction were investigated to help describe love vine resource acquisition as a parasite on host Brazilian pepper plants, and as an autotrophic plant. An investigation of ecological aspects of this parasitic interaction was done to determine whether physical or biological aspects of habitats may contribute to love vine parasitism on Brazilian pepper. These studies indicated that: 1) parasitism by love vine significantly decreased growth and reproduction of Brazilian pepper plants; 2) anatomical and physiological investigations indicated that love vine was primarily a xylem parasite on Brazilian pepper, but that some assimilated carbon nutrients may also be acquired from the host; 3) love vine is autotrophic (i. e., hemiparasitic), but is totally dependent on its host for necessary resources; 4) the occurrence of love vine parasitism on Brazilian pepper is mediated by physical characters of the biological community.

Ecosystem structure in disturbed and restored subtropical seagrass meadows

Shallow seagrass ecosystems frequently experience physical disturbance from vessel groundings. Specific restoration methods that modify physical, chemical, and biological aspects of disturbances are used to accelerate recovery. This study evaluated loss and recovery of ecosystem structure in disturbed seagrass meadows through plant and soil properties used as proxies for primary and secondary production, habitat quality, benthic metabolism, remineralization, and nutrient storage and exchange. The efficacy of common seagrass restoration techniques in accelerating recovery was also assessed. Beyond removal of macrophyte biomass, disturbance to seagrass sediments resulted in loss of organic matter and stored nutrients, and altered microbial and infaunal communities. Evidence of the effectiveness of restoration actions was variable. Fill placement prevented additional erosion, but the resulting sediment matrix had different physical properties, low organic matter content and nutrient pools, reduced benthic metabolism, and less primary and secondary production relative to the undisturbed ecosystem. Fertilization was effective in increasing nitrogen and phosphorus availability in the sediments, but concurrent enhancement of seagrass production was not detected. Seagrass herbivores removed substantial seagrass biomass via direct grazing, suggesting that leaf loss to seagrass herbivores is a spatially variable but critically important determinant of seagrass transplanting success. Convergence of plant and sediment response variables with levels in undisturbed seagrass meadows was not detected via natural recovery of disturbed sites, or through filling and fertilizing restoration sites. However, several indicators of ecosystem development related to primary production and nutrient accumulation suggest that early stages of ecosystem development have begun at these sites. This research suggests that vessel grounding disturbances in seagrass ecosystems create more complex and persistent resource losses than previously understood by resource managers. While the mechanics of implementing common seagrass restoration actions have been successfully developed by the restoration community, expectations of consistent or rapid recovery trajectories following restoration remain elusive.

Site specific growth of metal catalyzed silica nanowires for biological and chemical sensing

In this research the integration of nanostructures and micro-scale devices was investigated using silica nanowires to develop a simple yet robust nanomanufacturing technique for improving the detection parameters of chemical and biological sensors. This has been achieved with the use of a dielectric barrier layer, to restrict nanowire growth to site-specific locations which has removed the need for post growth processing, by making it possible to place nanostructures on pre-pattern substrates. Nanowires were synthesized using the Vapor-Liquid-Solid growth method. Process parameters (temperature and time) and manufacturing aspects (structural integrity and biocompatibility) were investigated. Silica nanowires were observed experimentally to determine how their physical and chemical properties could be tuned for integration into existing sensing structures. Growth kinetic experiments performed using gold and palladium catalysts at 1050°C for 60 minutes in an open-tube furnace yielded dense and consistent silica nanowire growth. This consistent growth led to the development of growth model fitting, through use of the Maximum Likelihood Estimation (MLE) and Bayesian hierarchical modeling. Transmission electron microscopy studies revealed the nanowires to be amorphous and X-ray diffraction confirmed the composition to be SiO2 . Silica nanowires were monitored in epithelial breast cancer media using Impedance spectroscopy, to test biocompatibility, due to potential in vivo use as a diagnostic aid. It was found that palladium catalyzed silica nanowires were toxic to breast cancer cells, however, nanowires were inert at 1μg/mL concentrations. Additionally a method for direct nanowire integration was developed that allowed for silica nanowires to be grown directly into interdigitated sensing structures. This technique eliminates the need for physical nanowire transfer thus preserving nanowire structure and performance integrity and further reduces fabrication cost. Successful nanowire integration was physically verified using Scanning electron microscopy and confirmed electrically using Electrochemical Impedance Spectroscopy of immobilized Prostate Specific Antigens (PSA). The experiments performed above serve as a guideline to addressing the metallurgic challenges in nanoscale integration of materials with varying composition and to understanding the effects of nanomaterials on biological structures that come in contact with the human body.

Aspects Allogenic Memory in the Gorgonian Coral Swiftia Exserta

Accelerated graft rejection can be used to determine immune memory in the gorgonian coral swiftia exserta. The extent ofthe persistence of immune memory will be determined in this experiment using replicate sets that are time elapsed from 1, 3, and 6 month. Although corals lack circulatory systems which can be a component of adaptive systemic immunity, this study will attempt to determine whether this gorgonian coral is capable of transmitting immune information throughout its colonial body. Results showed that at each of the time points; one, three, and six months the secondary response group and the primary response group were significantly different (at p=0.001) therefore, demonstrating long term immune memory. While the primary response group and the 3rd party specificity response group were similar, both were significantly different (at p=O. 001) from the secondary response group which shows the response to be specific, with memory applicable to the original antigen. Systemic immunity was not determined to be present for 15 em and one week after initial sensitization.

Site Specifc Growth of Metal Catalyzed Silica Nanowires for Biological and Chemical Sensing

In this research the integration of nanostructures and micro-scale devices was investigated using silica nanowires to develop a simple yet robust nanomanufacturing technique for improving the detection parameters of chemical and biological sensors. This has been achieved with the use of a dielectric barrier layer, to restrict nanowire growth to site-specific locations which has removed the need for post growth processing, by making it possible to place nanostructures on pre-pattern substrates. Nanowires were synthesized using the Vapor-Liquid-Solid growth method. Process parameters (temperature and time) and manufacturing aspects (structural integrity and biocompatibility) were investigated. Silica nanowires were observed experimentally to determine how their physical and chemical properties could be tuned for integration into existing sensing structures. Growth kinetic experiments performed using gold and palladium catalysts at 1050 ˚C for 60 minutes in an open-tube furnace yielded dense and consistent silica nanowire growth. This consistent growth led to the development of growth model fitting, through use of the Maximum Likelihood Estimation (MLE) and Bayesian hierarchical modeling. Transmission electron microscopy studies revealed the nanowires to be amorphous and X-ray diffraction confirmed the composition to be SiO2 . Silica nanowires were monitored in epithelial breast cancer media using Impedance spectroscopy, to test biocompatibility, due to potential in vivo use as a diagnostic aid. It was found that palladium catalyzed silica nanowires were toxic to breast cancer cells, however, nanowires were inert at 1µg/mL concentrations. Additionally a method for direct nanowire integration was developed that allowed for silica nanowires to be grown directly into interdigitated sensing structures. This technique eliminates the need for physical nanowire transfer thus preserving nanowire structure and performance integrity and further reduces fabrication cost. Successful nanowire integration was physically verified using Scanning electron microscopy and confirmed electrically using Electrochemical Impedance Spectroscopy of immobilized Prostate Specific Antigens (PSA). The experiments performed above serve as a guideline to addressing the metallurgic challenges in nanoscale integration of materials with varying composition and to understanding the effects of nanomaterials on biological structures that come in contact with the human body.