What Works in Honors: Discovering “London as a Detective Story”

An honors program director and university archivist/librarian team up to offer a two-week study abroad course that blends itinerant offerings of City as Text™ with fixed support for first-time student encounters with archival collections at the British Library and the National Archives

Using virtual spatial audio to aide visually impaired atheletes

Many people with visual impairments actively play soccer, however the task of making the game accessible is met with significant challenges. These challenges include: the need to constantly talk to signify location and detecting the positions of silent objects on the field. Our work aims to discover methods to help persons with visual impairments play soccer more efficiently and safely

Frost resistance of pea genotypes (Pisum sativum L.) grown in the field on ground level and raised beds, and under controlled laboratory conditions

The effect of raised bed culture on winter survival of ten pea genotypes (Pisum sativum L.), differing in inherent cold hardiness and growth habit, was studied under two climatic conditions: a moist semi-maritime winter (Corvallis, Oregon) and a cold continental winter (Weston, Oregon). An assessment of winter injury was based on three indices: percent survival, plant weight, and a visually assigned damage rating. Varying percentages of seven genotypes survived at Corvallis and of six at Weston. Planting on raised beds at Corvallis significantly increased the mean percent survival and plant weight and decreased the mean damage rating. Of two Corvallis planting dates, September 18 and October 10, 1975, the latter had a significantly higher mean percent survival and a lower mean damage rating. At Weston, the mean percent survival was higher on ground level plantings. Plant weight was not affected by planting method. At this location there was a significant interaction between planting method and genotype. Of the six surviving genotypes only the two least hardy had significantly higher percent survival on ground level plantings. Controlled freezing tests between -2 and -10° C were conducted on four genotypes, AW, WH2, INTl, and S4, to determine their relative levels of inherent cold hardiness and cold acclimating ability. An electrolyte leaching method of determining the extent of freezing injury ranked the genotypes as follows, from most hardy to least: AW = WH2 > INTl > S4. A visual estimation of damage ranked the genotypes as follows: WH2 > AW > INTl > S4. In comparison, percent survival in the field studies ranked the four genotypes: AW > WH2 > INT1 > S4. Genotypes with a compact growth habit, AW and WH2, acclimated [less than or equal to] 4° C, whereas those with an upright growth habit, INTl and S4, acclimated 1-2° C

Electrochemical Oxidative Fluorination of an Oxide Perovskite

We report on the electrochemical fluorination of the A-site vacant perovskite ReO3 using high-temperature solid-state cells as well as room-temperature liquid electrolytes. Using galvanostatic oxidation and electrochemical impedance spectroscopy, we find that ReO3 can be oxidized by approximately 0.5 equiv of electrons when in contact with fluoride-rich electrolytes. Results from our density functional theory calculations clearly rule out the most intuitive mechanism for charge compensation, whereby F-ions would simply insert onto the A-site of the perovskite structure. Operando X-ray diffraction, neutron total scattering measurements, X-ray spectroscopy, and solid-state 19F NMR with magic-angle spinning were, therefore, used to explore the mechanism by which fluoride ions react with the ReO3 electrode during oxidation. Taken together, our results indicate that a complex structural transformation occurs following fluorination to stabilize the resulting material. While we find that this process of fluorinating ReO3 appears to be only partially reversible, this work demonstrates a practical electrolyte and cell design that can be used to evaluate the mobility of small anions like fluoride that is robust at room temperature and opens new opportunities for exploring the electrochemical fluorination of many new materials

Tobacco seeds simultaneously over-expressing Cu/Zn-superoxide dismutase and ascorbate peroxidase display enhanced seed longevity and germination rates under stress conditions

Reactive oxygen species (ROS) are produced during seed desiccation, germination, and ageing, leading to cellular damage and seed deterioration and, therefore, decreased seed longevity. The effects of simultaneous over-expression of two antioxidant enzymes on seed longevity and seed germination under stressful conditions were investigated. Transgenic tobacco simultaneously over-expressing the Cu/Zn-superoxide dismutase (CuZnSOD) and ascorbate peroxidase (APX) genes in plastids showed normal growth and seed development. Furthermore, the transgenic seeds displayed increased CuZnSOD and APX enzymatic activities during seed development and maintained antioxidant enzymatic activity after two years of dried storage at room temperature. The two-year stored non-transgenic seeds (aged NT seeds) had higher levels of ion leakage than the two-year stored transgenic seeds (aged CA seeds), indicating membrane damage caused by ROS was more severe in the aged NT seeds than the aged CA seeds. The aged CA seeds decreased germination rates as compared to newly harvested transgenic and non-transgenic seeds. The aged CA seeds, however, significantly increased germination rates under various abiotic stress conditions as compared to aged NT seeds. These data strongly suggest that simultaneous over-expression of the CuZnSOD and APX genes in plastids improves seed longevity and germination under various environmental stress conditions by attenuating the effects of oxidative stress produced by elongated storage conditions and harsh environmental stresses

One tissue, two fates: different roles of megagametophyte cells during Scots pine embryogenesis

In the Scots pine (Pinus sylvestris L.) seed, embryos grow and develop within the corrosion cavity of the megagametophyte, a maternally derived haploid tissue, which houses the majority of the storage reserves of the seed. In the present study, histochemical methods and quantification of the expression levels of the programmed cell death (PCD) and DNA repair processes related genes (MCA, TAT-D, RAD51, KU80, and LIG) were used to investigate the physiological events occurring in the megagametophyte tissue during embryo development. It was found that the megagametophyte was viable from the early phases of embryo development until the early germination of mature seeds. However, the megagametophyte cells in the narrow embryo surrounding region (ESR) were destroyed by cell death with morphologically necrotic features. Their cell wall, plasma membrane, and nuclear envelope broke down with the release of cell debris and nucleic acids into the corrosion cavity. The occurrence of necrotic-like cell death in gymnosperm embryogenesis provides a favourable model for the study of developmental cell death with necrotic-like morphology and suggests that the mechanism underlying necrotic cell death is evolutionary conserved