Hormonally mediated maternal effects in birds

The main aim of this thesis was to investigate the effects of environmental conditions, particularly unpredictable or potentially negative ones, on the maternal transmission of the primary avian stress hormone, corticosterone, to developing embryos. We currently lack information on the extent to which conditions in the maternal environment are transmitted to the offspring in birds via egg compositional changes. It is possible that maternally derived hormonal signals communicate information about the external environment to developing embryos and directly influence the fitness of their offspring in a negative or positive way. I found, using captive zebra finches, that the experimental stressor of unpredictable food availability (as these birds are used to ad libitum food) experienced by mothers can elevate yolk CORT concentrations, but only when combined with the additional demand of laying a replacement clutch (potentially a buffering system to prevent mild stressors impacting on CORT transmission to the embryo). I then looked at yolk CORT concentrations in two populations of gulls (herring and lesser black-backed gulls) in which the population trajectories differed depending on environmental conditions (potentially a reflection of different exposures to stressful stimuli). The results however did not support this hypothesis, as there were no differences according to habitat type or between species (where they coexist). This would suggest that the different environmental circumstances (harsher for the herring gull) experienced by these two species are not reflected in differences in their eggs (at least in terms of CORT). This could be the result of the eggs being buffered from the maternal CORT environment or it may be that the difficult environmental conditions are not occurring during the breeding season. We also identified that experimental human disturbance during the laying period does not appear to elevate yolk CORT concentrations, although there was a trend for concentrations to be higher following the loss of the first clutch in the herring gull (as seen in the zebra finches). I also measured yolk CORT concentrations in Common Eider eggs and looked for differences according to the degree of nest shelter. I found no relationship between shelter and yolk CORT, but birds that laid in more sheltered sites had, on average, smaller eggs. This may indicate lesser quality birds are nesting in the sheltered sites and that yolk CORT is not affected by maternal condition. Finally, I looked at another mechanism through which information relating to the maternal environment could be transferred to the embryo. I investigated whether there were any links between maternally derived immunity and CORT by comparing the anti-microbial lysozyme and CORT concentrations in the albumen. I found no correlation between CORT and lysozyme, suggesting that CORT may not affect lysozyme production. It may be that other factors such as colony density and ‘cleanliness’ are more important in determining the concentrations of lysozyme deposited in the egg or that lysozyme production is not sufficiently costly to be influenced by the maternal stress state. The overall theme of my findings is that CORT concentrations in eggs do not appear to vary much with maternal environments. I will discuss these findings in their broader ecological and evolutionary context and discuss if stress hormones are indeed being used as adaptive signals for preparing the embryo for its postnatal environment

Remote Sensing of Green Leaf Area Index in Maize and Soybean: From Close-Range to Satellite

This dissertation seeks to explore alternative methodologies for estimating green leaf area index (LAI) and crop developmental stages. Specifically this research [1] developed an approach for creating a Moderate Resolution Imaging Spectroradiometer (MODIS) high spatial resolution product for estimating green LAI on the base of data collected using two different close-range sensors. It was determined that the vegetation indices (VIs) Wide Dynamic Range Vegetation Index (WDRVI) and Enhanced Vegetation Index 2 (EVI2) were capable of accurate estimation of green LAI from MODIS 250 m data using models developed from hyperspectral (RMSE \u3c 0.69 m2 m-2; CV \u3c 33%) or multispectral sensors (RMSE \u3c 0.69 m2 m-2; CV \u3c 34%). [2] Explored a new approach for maximizing the sensitivity of VIs to green LAI. Rather than use one VI, we suggested using multiple VIs in different LAI dynamic ranges. Thus, the sensitivity of the VI to the green LAI was preserved and simpler linear models could be used instead of complex non-linear ones. Two combined vegetation indices (CVI) were presented using near infrared and either the red or red edge bands and were accurate in estimating green LAI. While the red band is more common in satellite sensors, the indices use red edge band were found to be species independent for maize and soybean. The two species-independent VIs used in the CVI were Red Edge Normalized Difference Index (Red Edge NDVI) and Red Edge Chlorophyll Index (CIred edge). [3] Algorithms were developed for estimating green LAI in four vastly different crops (maize, potato, soybean, and wheat) that do not require re-parameterization. The most promising VIs for developing a unified algorithm utilized either a green or red edge bands. [4] It was found that, in addition to traditionally used (VIs), the 2-dimensional spectral spaces (e.g. red vs. green reflectance) were capable of identifying four distinct stages of crop development (e.g. soil/residue, green-up, vegetative, and senescence). Advisor: Anatoly A. Gitelso

Unfamiliar face recognition : Security, surveillance and smartphones

A person’s ability to recognize familiar faces across a wide range of viewing conditions is one of the most impressive facets of human cognition. As shown in Figure 1, it is easy to conclude, for a known individual, that each image in the set shows the same person (British Prime Minister David Cameron), despite a wide range of variation in viewing angle, physical appearance, camera and lighting. In fact, familiar face recognition performance is often at or near ceiling level, even when the images are of poor quality [1] or artificially distorted. [2] At first glance, the aptitude for familiar face recognition may suggest a similar level of expertise for the recognition of unfamiliar faces, thus the reliance on face-to-photo ID for identity verification. [3] This is not the case, as recent research shows people are surprisingly poor at recognizing new instances of an unfamiliar person. The poor recognition of unfamiliar faces is a concern for the United States. Many preliminary screenings involve facial recognition by security agents. In order for this method to be effective, more robust training for security agents needs to be established. The Department of Defense utilizes facial and iris recognition technologies in order to eliminate human error in identifying persons of interest during surveillance operations. [4] DoD guidelines should be implemented by security agent guidance programs to ensure best practices in identification of potential threats

Reduce, Reuse, Reengineer

Our senior project is a research exploration of renewable energy. We recognized there is a major need in the world for the advancement of green power sources. For our project, we wanted to go beyond what we have learned in our Cal Poly architectural engineering classes and to use some of our own creativity to investigate the possibilities of renewable energy from a structural perspective. The guiding question we asked ourselves was, “as architectural engineering students, how could we shift our world to use more renewable energy?” To start our journey off, was the original inspiration from the work of a German structural engineer named Jörg Schlaich and his design for a renewable power source called solar updraft tower that we touched on in our History of Structures class

A Review of Thick-Billed Murre Banding in the Canadian Arctic, 1950–2010

Banding of Thick-billed Murres Uria lomvia in the Canadian Arctic was initiated by L.M. Tuck in the 1950s, when he visited three of the largest breeding colonies in Canada. Up to 2010, banding had been carried out at eight of the 10 major breeding colonies, with totals of more than 1000 birds banded at Coburg Island and Cape Hay, Bylot Island, in the High Arctic and at Digges Sound and Coats Island in northern Hudson Bay. Because murres are long-lived birds, large-scale banding can continue to provide useful results for decades. A total of about 89 000 bandings in Arctic Canada resulted in 1757 usable recoveries up to 2010, the vast majority of which were birds killed by hunters in West Greenland or Newfoundland and Labrador. There was no apparent change in the large-scale geographical pattern of recoveries over the period reviewed, but the proportion of bands recovered has fallen. Several periods of higher- or lower-than-expected recoveries can be attributed to particular events: anomalous ice conditions, intensive gill-net fisheries, and oiling at sea. Thus, banding provided a useful tool not only for identifying migration and wintering areas, but also for identifying transient sources of increased mortality.Les débuts du baguage des guillemots de Brünnich Uria lomvia dans l’Arctique canadien remontent aux années 1950, sous l’égide de L.M. Tuck à l’occasion de sa visite de trois des plus grandes colonies de nidification au Canada. Jusqu’en 2010, le baguage a été effectué à huit des dix grandes colonies de nidification, pour un total de plus de 1 000 oiseaux bagués à l’île Coburg, à cap Hay et à l’île Bylot, dans l’Extrême-Arctique, ainsi qu’au détroit de Digges et à l’île Coats, dans le nord de la baie d’Hudson. Puisque les guillemots de Brünnich sont des oiseaux qui vivent longtemps, le baguage à grande échelle peut donner des résultats pendant des années. Jusqu’en 2010, les quelque 89 000 baguages effectués dans l’Arctique canadien se sont traduits par 1 757 récupérations d’oiseaux utilisables, la vaste majorité d’entre eux ayant été tuée par des chasseurs de l’ouest du Groenland ou de Terre-Neuve-Labrador. Il n’y avait aucun changement apparent dans le modèle géographique à grande échelle des oiseaux récupérés au cours de la période examinée, mais la proportion de bagues récupérées a diminué. Plusieurs périodes de récupérations plus grandes ou moins grandes que prévu peuvent être attribuées à des événements particuliers : un état anormal des glaces, la pêche intensive au filet maillant et le mazoutage en mer. Par conséquent, le baguage a représenté un outil utile non seulement pour déterminer les lieux de migration et les aires d’hivernage, mais aussi pour repérer les sources transitoires de mortalité accrue.Mots clés : L.M. Tuck, guillemot de Brünnich, Uria lomvia, chasse, baguage, population

Effect of Microwaved Water on the Growth of Tomato (Lycopersicon esculentum) Seedlings

The purpose of this project was to investigate the effects of microwave-heated water on the growth of tomato (Lycopersicon esculentum) seedlings, in order to observe the effects of microwave radiation. Three groups of seedlings were used, one treated with tap water, one with microwaved water and one with boiled water and these were studied for 5 weeks. Analysis of the results showed that both microwaved and boiled water increased the overall growth rate of the length of the stem of the seedlings compared to tap water, with boiled water having the most positive effect. This suggests that the effects of microwave radiation were not harmful to the treated plants and therefore the use of microwave appliances in households to heat substances for human consumption may not alter these substances negatively or affect human health

Analysis of fluorine via 19F(n,)20F decay in the presence of a Na interferant using NAA [abstract]

Abstract only availableSociety's concern with the development of innovative diagnostic tools in medicine has prompted a great deal of interest in research. An important area of research includes the development of molecular imaging agents. These agents hold promise for noninvasive in vivo imaging, quantification, and monitoring of important biomarkers for several diseases including atherosclerosis and cancer. This area of research has benefited greatly from instrumental neutron activation analysis. INAA is an analytical technique that is useful for performing quantitative multi-elemental analysis. NAA is superior to other forms of analysis of its ability to simultaneously analyze several elements in a sample and it offers high sensitivity; part per million to low part per billion level. The imaging agent of interest in this project is a lipid encapsulated, liquid perfluorocarbon nanoparticle directly coupled to a selective v3-integrin ligand. The nanoparticle also contains the paramagnetic contrast agent gadolinium linked to the nanoparticle as Gd-DTPA-bis-oleate.1 Utilizing INAA, analysis of this molecular imaging agent for its concentration in biological tissue, specifically, rabbit aortas via a 19F(n, )20F reaction. Measurement of fluorine in tissue is particularly difficult due to fluorine's short half-life (t1/2 = 11s) and sodium's interference via a fast neutron reaction. INAA will also be employed to quantitatively determine the concentration of gadolinium in biological tissues. These measurements will allow for the comparison of Gd to F ratio pre-injection to the Gd to F ratio post-injection. Efficiency of Gd's arrival at the target location will be determined by the comparison of these ratios. (Image included in PDF

Rocket-Induced Magnetohydrodynamic Ejector: A Single-Stage-to-Orbit Advanced Propulsion Concept

During the atmospheric boost phase of a rocket trajectory, magnetohydrodynamic (MHD) principles can be utilized to augment the thrust by several hundred percent without the input of additional energy. The concept is an MHD implementation of a thermodynamic ejector. Some ejector history is described and some test data showing the impressive thrust augmentation capabilities of thermodynamic ejectors are provided. A momentum and energy balance is used to derive the equations to predict the MHD ejector performance. Results of these equations are compared with the test data and then applied to a specific performance example. The rocket-induced MHD ejector (RIME) engine is described and a status of the technology and availability of the engine components is provided. A top level vehicle sizing analysis is performed by scaling existing MHD designs to the required flight vehicle levels. The vehicle can achieve orbit using conservative technology. Modest improvements are suggested using recently developed technologies, such as superconducting magnets, which can improve predicted performance well beyond those expected for current single-stage-to-orbit (SSTO) designs