The tumor microenvironment is a tangled web of multiple cell types, extracellular matrix components, and a multitude of cell signaling pathways frequently contribute to poor outcomes, which make cancer the second leading killer in the United States. A better understanding of how these constituents interact will inevitably facilitate development of novel cancer therapeutics and diagnostics. To advance scientific discovery towards this goal, innovative experimental techniques are required. In this dissertation, new research methods for probing cell communication at a single to multi cell level within 3D models of the tumor microenvironment are presented. Optical trapping, composite nanocapsules (i.e., gold-coated liposomes), and 3D cell culture models were the foundation for the development of these research tools. The first aim of this dissertation was to optimize our ability to optically manipulate gold-coated liposomes for the purpose of delivering molecular content to cells. The second aim was to apply optical manipulation of gold-coated liposomes to quantitatively deliver signaling molecules into a single cell to activate communication. The third aim was to develop a 3D model of the tumor microenvironment and demonstrate cell communication within this physiologically accurate architecture. The basis for this work was gold-coated liposomes' strong plasmon resonance with visible to near infrared (NIR) wavelengths of light, which enabled photo-thermal conversion and optical trapping. To identify preferred conditions for optical manipulation of gold-coated liposomes for delivering content into cells, gold-coated liposomes made with different dielectric properties were optically trapped under various laser modulation schemes and thoroughly characterized, enabled by high speed (kHz) imaging. Application of this technique was realized by precise delivery of molecular agents into a single cell (i.e., optical injection). As a demonstration of optical injection, the NIR trapping beam was utilized to propel gold-coated liposomes encapsulating inositol trisphosphate (IP3) into a single cell to initiate calcium (Ca²⁺) signaling. In another method for intracellular delivery, cells were preloaded with similar gold-coated liposomes, internalized by macropinocytosis, and then exposed to on-resonant laser light to trigger on-demand release of IP3 to activate Ca²⁺ signaling. Lastly, a 3D cell culture model of ovarian cancer microenvironment was developed as a platform for interrogating cell signaling. The in vitro model comprised human ovarian cancerous epithelial cells grown upon a collagen and human fibroblast stroma recapitulating architecture of human tissue. Gold-coated liposomes encapsulating signaling molecules, optical manipulation, and a 3D model of ovarian cancer, a trio of versatile experimental tools opens new opportunities for studying the tumor microenvironment.

Geluoninių plėviasparnių, apsigyvenančių lizdavietėse-gaudyklėse bendrijos, yra potencialūs ekologinių pokyčių ir buveinių kokybės bioindikatoriai sausumos ekosistemose, todėl vis dažniau naudojamos įvairiuose tyrimuose. Darbo tikslas buvo įvertinti lizdavietės rodiklių ir grobio, reikalingo palikuonims aprūpinti, gausumo įtaką lizdavietėse-gaudyklėse apsigyvenančių klosčiavapsvių rūpinimosi palikuonimis elgsenai. Tyrimų metu buvo ištirta lizdavietės skersmens ir gylio įtaka 13-kos lizdavietėse-gaudyklėse apsigyvenančių vapsvų rūšių lizdo struktūrai, palikuonių aprūpinimo maistu elgsenai ir lyčių santykiui; kai kurioms rūšims nustatyti optimalūs lizdavietės rodikliai. Taip pat buvo ištirtas, dažniausiai lizdavietėse-gaudyklėse pasitaikiusios rūšies, Symmorphus allobrogus vystymasis nuo kiaušinio iki suaugėlio; palyginti skirtingų lyčių individų augimo greičiai ir svorio pokyčiai vystymosi metu. Atliktas laboratorinis eksperimentas, kurio rezultatai parodė, kad akelių skaičius lizde būna didesnis, jeigu aplinkoje yra didesnis maisto, reikalingo palikuonims aprūpinti, kiekis. Taip pat įvertinta patelės amžiaus įtaka rūpinimosi palikuonimis elgsenai. Darbe taip pat pateikiamas sinantropinių, Lietuvoje lizdavietėse-gaudyklėse apsigyvenančių plėviasparnių rūšių sąrašas. / Since Hymenoptera Aculeate are known to be bioindicators, which are sensitive to environment change, fragmentation of habitats and antropogenous impact, these insects may have an importance in environment conservation. The purpose of our study was to establish impact of nesting cavity parameters and prey abundance on the nesting behaviour of solitary xylicolous wasps. We studied nest structure and the influence of nesting cavity width and length on progeny size and sex ratio in 13 wasp species. The development of the most common synanthropic xylicolous wasp in Lithuania, Symmorphus allobrogus, has been investigated: the assimilation of prey and weight loss during development from larva to adult in both sexes have been compared. Results of a laboratory experiment using S. allobrogus as a model species demonstrated that the amount of prey available in the environment affects the number of cells in the nest of solitary wasp. The list of solitary Hymenoptera inhabiting trap-nests in Lithuania are presented.

Since Hymenoptera Aculeate are known to be bioindicators, which are sensitive to environment change, fragmentation of habitats and antropogenous impact, these insects may have an importance in environment conservation. The purpose of our study was to establish impact of nesting cavity parameters and prey abundance on the nesting behaviour of solitary xylicolous wasps. We studied nest structure and the influence of nesting cavity width and length on progeny size and sex ratio in 13 wasp species. The development of the most common synanthropic xylicolous wasp in Lithuania, Symmorphus allobrogus, has been investigated: the assimilation of prey and weight loss during development from larva to adult in both sexes have been compared. Results of a laboratory experiment using S. allobrogus as a model species demonstrated that the amount of prey available in the environment affects the number of cells in the nest of solitary wasp. The list of solitary Hymenoptera inhabiting trap-nests in Lithuania are presented. / Geluoninių plėviasparnių, apsigyvenančių lizdavietėse-gaudyklėse bendrijos, yra potencialūs ekologinių pokyčių ir buveinių kokybės bioindikatoriai sausumos ekosistemose, todėl vis dažniau naudojamos įvairiuose tyrimuose. Darbo tikslas buvo įvertinti lizdavietės rodiklių ir grobio, reikalingo palikuonims aprūpinti, gausumo įtaką lizdavietėse-gaudyklėse apsigyvenančių klosčiavapsvių rūpinimosi palikuonimis elgsenai. Tyrimų metu buvo ištirta lizdavietės skersmens ir gylio įtaka 13-kos lizdavietėse-gaudyklėse apsigyvenančių vapsvų rūšių lizdo struktūrai, palikuonių aprūpinimo maistu elgsenai ir lyčių santykiui; kai kurioms rūšims nustatyti optimalūs lizdavietės rodikliai. Taip pat buvo ištirtas, dažniausiai lizdavietėse-gaudyklėse pasitaikiusios rūšies, Symmorphus allobrogus vystymasis nuo kiaušinio iki suaugėlio; palyginti skirtingų lyčių individų augimo greičiai ir svorio pokyčiai vystymosi metu. Atliktas laboratorinis eksperimentas, kurio rezultatai parodė, kad akelių skaičius lizde būna didesnis, jeigu aplinkoje yra didesnis maisto, reikalingo palikuonims aprūpinti, kiekis. Taip pat įvertinta patelės amžiaus įtaka rūpinimosi palikuonimis elgsenai. Darbe taip pat pateikiamas sinantropinių, Lietuvoje lizdavietėse-gaudyklėse apsigyvenančių plėviasparnių rūšių sąrašas.

Soybean aphid, Aphis glycines Matsumura, is an important pest of North American soybean. This dissertation identifies and addresses knowledge gaps, and integrates existing knowledge regarding distribution and abundance of this species. Early summer soybean colonization patterns by A. glycines were examined relative to landscape parameters, including density of overwintering hosts (buckthorn). An information-theoretic model selection approach was used to determine which landscape parameters were most influential in the distribution of colonizing aphids. Though buckthorn abundance best explained aphid colonization and population density, a density-dependent effect was observed. When aphid populations were low, more aphids were found in the vicinity of buckthorn, when aphid populations were higher, more aphids were found farther from buckthorn. Suction trap captures of migrating populations of A. glycines from 2005-2009 from a suction trap network covering much of central North America were examined. A model selection approach was used to determine the environmental triggers of summer and fall aphid flights, and spatial analysis and modeled wind trajectories were used to examine patterns in the abundance of alates. Two alate activity peaks were observed in fall. In summer, formation of alates was a function of field infestation. A tritrophic population model was built using DYMEX, a mechanistic lifecycle based modeling software package. The model incorporated soybean, A. glycines, and three natural enemy species, interacting based on phenological, physiological and functional response data available in the literature. The model was validated using Ontario field data, and several simulations were performed and are discussed. An evaluation of proposed control strategies for efficacy and impact on natural enemies and the environment was conducted. Two novel concepts are presented: the natural enemy unit, a standardization of the impact of predator guild on prey populations by the number of prey an individual predator can eat, and the selectivity index, where the selectivity of a pesticide is a function of the change in ratio of natural enemy units to prey before and after treatment. The selectivity index was inversely correlated with the Environmental Impact Quotient (EIQ), a theoretical measure of impact, validating EIQ's field applicability. / Natural Sciences and Engineering Research Council of Canada; The Keefer family trust; the Mary Edmunds Williams trust, the family of Fred W. Presant, and the University of Guelph provided scholarship and fellowship funds. Research was funded by a grant to Rebecca Hallett and Art Schaafsma from the Agriculture and Agri-Food Canada Pest Management Centre’s Pesticide Risk Reduction Program.

No description available.

This thesis presents the results of recent sampling of the Q’umu?xs Village site (DkSf-19) at Comox Harbour, British Columbia. Bucket auger and column sampling was undertaken to ascertain resource use patterns associated with the unique abundance of wooden stake fish traps located in Comox Harbour through zooarchaeological analysis of fish remains. Fish remains were identified and quantified to trace changes in resource use and linked to the chronology of fish trap use. Incorporating the theoretical frameworks of human behavioural ecology (optimal foraging models), intensification, household archaeology, and the archaeology of complex hunter-gatherers, this thesis discusses the use of fish traps in Comox Harbour in relation to larger questions of Northwest Coast social and economic complexity, in particular the emphasis on herring seen in the fish remains.

The Canadian Penning Trap mass spectrometer located at Argonne National Laboratory has been built for the purpose of studying the masses of both stable and unstable nuclides. For this thesis 18 proton-rich unstable nuclides of elements Nb, Mo, Tc, Ru and Rh have been measured with this apparatus to an average precision of 7.8 x10^−8. The masses of 6 of these nuclides had not been measured when this thesis was undertaken, and 4 more were not known to the precisions required for use in astrophysical nucleosynthesis models. The masses of these nuclides were of particular interest as the reaction paths of two proposed nucleosynthetic processes, the rp and νp processes, pass through this region. The rp process is thought to occur in X-ray bursts and directly affects the X-ray luminosity which is emitted from these objects. The νp process is thought to occur in the inner regions of the material ejected during a core-collapse supernova explosion and is of particular interest as it may answer some outstanding questions about the origins of the chemical elements in the Universe. The Canadian Penning Trap and associated apparatus were used to determine the masses of 18 nuclides, some for the first time ever. Our measurements improve the precision on all of the masses, by a factor of 70 in some cases. Our results are necessary to determine the proton-separation energies for these nuclides which are critical for determining the paths and reaction rates of the rp and νp processes. In particular, the effect of our measurements of 92Ru and 93Rh on the expected production ratio of 92Mo to 94Mo in the νp process, and the effect of our measurement of 87Mo on the path of this process will be discussed.

Quadrupole ion trap(QIT) mass spectrometry has become one of the most widelyused tools in the analysis of the structure of small molecules. The motion of the ionsstored in the quadrupole ion trap is extremely important. This ion motion within thequadrupole ion trap is controlled by several factors including the m/z ratio and thecollisional cross section of the ion. Investigation of ion motion within the QIT has thepotential to elucidate a new way to separate ions based on these factors. DC tomographyexperiments allow for the trajectory of the ion motion to be measured withoutmodifications to the ion trap. The ability to use DC tomography for separation ofisomeric ions on a commercial GC/MS system was investigated.Investigation of the mass range within the ion trap is necessary for the analysis ofa wide range of molecules. The ability of the quadrupole ion trap to perform MS/MSanalyses can provide insight into the structural information of many compounds.However, there exists a low mass cut-off (LMC) within the quadrupole ion trap and thusinformation about the low m/z fragments from a parent ion is lost. Schwartz and coworkerspresented a new technique labeled pulsed q dissociation (PQD) at the 53rdAnnual ASMS Conference in San Antonio TX in 2005. PQD eliminates the LMC byperforming CID at a qz of 0.4 but, then immediately lowering the q level before the massscan in a linear ion trap. By operating the quadrupole ion trap in this same manner, lowm/z product ions can be detected. This technique and elucidation of the energetic processcontained within PQD were explored further using a modified commercial quadrupoleion trap and the results discussed in this work.

Shandong Province, renowned as China’s greatest agricultural province, is dominated by smallholders growing rain-fed crops and vulnerable to severe weather shocks that can increase poverty rates. Weather index insurance, an innovative agricultural risk management product, may be an effective mechanism to address vulnerability to catastrophic weather risk in rural regions of China, including Shandong. This project evaluated current household livelihood and risk management strategies and farmer interest in weather index insurance. Data from 174 participants were collected using a methodology that included focus groups, questionnaires, and personal interviews. Despite limited access to formal financial services, Shandong farmers generally employ informal, well-diversified income strategies and rely on no-interest informal loans from community members to manage adverse impacts of natural disasters, such as drought. Households sometimes rely on reducing consumption as a risk coping strategy; however, unlike many regions of the world, Shandong farmers do not tend to sell livelihood assets to manage weather shocks. A majority of interviewed participants were interested in weather index insurance after they understood its basic concept; however, participants expressed concerns regarding basis risk and program implementation.

Road expansion and increased traffic likely exacerbates barriers to amphibian migration and dispersal. Within British Columbia’s south Okanagan valley there is particular concern that the COSEWIC-listed blotched tiger salamander (Ambystoma mavortium melanostictum) and Great Basin spadefoot (Spea intermontana) are vulnerable to road effects in their annual movements from upland overwintering habitat to lowland breeding areas. My study utilizes a before after control impact approach to assess amphibian movement and population threats across this highway-bisected landscape. Throughout the spring and summer of 2010-2012, fifty two kilometers of roadways (31 km of highway, 21 km of paved backroad) were repeatedly surveyed from the Canada-USA border to north of Oliver, BC; surveys were carried out utilising vehicles and on foot. Along Highway 97, a three kilometer four-lane highway expansion project was constructed through 2010 and open to traffic use in 2011. Adjacent to a floodplain, survey effort was focused throughout this transect for informed roadkill mitigation structure placement and ongoing ecopassage effectiveness monitoring. Automated camera trap monitoring of culverts within highly concentrated amphibian road hotspots during spring and summer 2011 (three culverts) and 2012 (two culverts) resulted in over eight hundred amphibian culvert events observed. Two sample Wilcoxon tests revealed differences between years in amphibian occurrence between 2010 and 2012 (W = 4679.5, p= 0.02), and mortalities among transect areas, with the largest differences between years within the Osoyoos passing lanes transect. Amphibian mortalities within the passing lanes transect were significantly reduced with the implementation of mitigation structures (x̅2010= 13.2 ± 32.5, x̅2011= 4.7 ± 12.8, x̅2012= 2.3 ± 7.3; 2010 vs. 2012: W= 1535.5, p< 0.001). Roadkill mitigation structures proved effective in observed amphibian occurrence of the entire passing lanes stretch as well as at distances 100 m and 200 m from observed culverts. Double fenced areas resulted in a 94% reduction in amphibian road occurrence. Five species of amphibians were observed over the three survey years (4051 road incidences over 657 survey hours): Pacific chorus frog (Pseudacris regilla), Western toad (Anaxyrus boreas), long-toed salamander (Ambystoma macrodactylum) plus blotched tiger salamander and Great Basin spadefoot. This study aims to provide a better understanding of amphibian hotspots on roadways and ecopassage use within the south Okanagan. It may act as a catalyst to further wildlife-vehicle interaction studies with improved mitigation solutions for amphibian roadway fatalities.