Membrane fluidity and temperature sensing are coupled via circuitry comprised of Ole1, Rsp5, and Hsf1 in Candida albicans

Peer reviewedPublisher PD

Surviving the heat of the moment : a fungal pathogens perspective

Peer reviewedPublisher PD

Linking academic emotions and student engagement: mature-aged distance students’ transition to university

This is an Accepted Manuscript of an article published by Taylor & Francis in Journal of Further and Higher Education on 2013, available online: https://www.tandfonline.com/doi/full/10.1080/0309877X.2014.895305Research into both student engagement and student emotions is increasing, with widespread agreement that both are critical determinants of student success in higher education. Less researched are the complex, reciprocal relationships between these important influences. Two theoretical frameworks inform this paper: Pekrun’s taxonomy of academic emotions and Kahu’s conceptual framework of student engagement. The prospective qualitative design aims to allow a rich understanding of the fluctuating and diverse emotions that students experience during the transition to university and to explore the relationships between academic emotions and student engagement. The study follows 19 mature-aged (aged 24 and over) distance students throughout their first semester at university, using video diaries to collect data on their emotional experiences and their engagement with their study. Pre and post-semester interviews were also conducted. Findings highlight that different emotions have different links to engagement: as important elements in emotional engagement, as inhibitors of engagement and as outcomes that reciprocally influence engagement. There are two key conclusions. First, student emotions are the point of intersection between the university factors such as course design and student variables such as motivation and background. Second, the flow of influence between emotions, engagement, and learning is reciprocal and complex and can spiral upwards towards ideal engagement or downwards towards disengagement and withdrawal.Publishe

Space and time to engage: Mature-aged distance students learn to fit study into their lives

This is an Accepted Manuscript of an article published by Taylor & Francis in International Journal of Lifelong Education on 2014, available online: https://www.tandfonline.com/doi/full/10.1080/02601370.2014.884177Student engagement, a student’s emotional, behavioural and cognitive connection to their study, is widely recognized as important for student achievement. Influenced by a wide range of personal, structural and sociocultural factors, engagement is both unique and subjective. One important structural factor shown in past research to be a barrier for distance students is access to quality space and time. This qualitative study followed 19 mature-aged distance students and their families, exploring how they learned to manage their space and time throughout their first semester at university. Institutions often claim that distance study and the increased use of technology overcomes barriers of space and time; however, the findings from this study suggest it merely changes the nature of those barriers. The ideal space and time for these students was individual and lay at the intersection of three, sometimes competing, demands: study, self and family. A critical influence on success is family support, as is access to financial resources. Learning what constitutes ideal space and time for engagement is an important part of the transition to university. The institution has a vital role to play in aiding this process by ensuring flexibility of course design is maintained, providing more flexible advice and targeting support at this important issue.falsePublishe

The effect of external forces on discrete motion within holographic optical tweezers

Holographic optical tweezers is a widely used technique to manipulate the individual positions of optically trapped micron-sized particles in a sample. The trap positions are changed by updating the holographic image displayed on a spatial light modulator. The updating process takes a finite time, resulting in a temporary decrease of the intensity, and thus the stiffness, of the optical trap. We have investigated this change in trap stiffness during the updating process by studying the motion of an optically trapped particle in a fluid flow. We found a highly nonlinear behavior of the change in trap stiffness vs. changes in step size. For step sizes up to approximately 300 nm the trap stiffness is decreasing. Above 300 nm the change in trap stiffness remains constant for all step sizes up to one particle radius. This information is crucial for optical force measurements using holographic optical tweezers

Non-line-of-sight tracking of people at long range

A remote-sensing system that can determine the position of hidden objects has applications in many critical real-life scenarios, such as search and rescue missions and safe autonomous driving. Previous work has shown the ability to range and image objects hidden from the direct line of sight, employing advanced optical imaging technologies aimed at small objects at short range. In this work we demonstrate a long-range tracking system based on single laser illumination and single-pixel single-photon detection. This enables us to track one or more people hidden from view at a stand-off distance of over 50~m. These results pave the way towards next generation LiDAR systems that will reconstruct not only the direct-view scene but also the main elements hidden behind walls or corners

Flower Visitation in Relation to Pollen and Nectar Nutrition: Implications for Pollinator Habitat and Conservation

Pollination of both wild and crop plants is at a crossroads; honey bee populations are experiencing losses at a higher rate than ever before, and some native bee species are declining in abundance to the point of being listed as endangered species. A few examples of these threats include pesticide exposure, habitat loss, and climate change. In response to bee population declines, conservation efforts have been initiated to increase habitat quality for bees by planting pollinator reservoirs or gardens. Plants provide nutrition to bees in the form of pollen and nectar. Several studies have shown links between higher nutritional quality in pollen and nectar and increased fitness in the following generations of bees. Our knowledge of bee nutrition has increased dramatically by studying the managed honey bee (Apis mellifera L.) and several species of the commercially available bumble bees, but little is known of the nutritional requirements of wild native bees. In Chapter One I summarized the published literature on managed bee and wild native bee nutrition. A synthesis of this information was used to develop a speculative dissertation on wild native bee nutrition. Chapter Two presents the results of my research conducted with the objective of determining the role of nutritional quality of pollen and nectar both directly and indirectly on bee visitation to flowers in the field. I hypothesized that pollen and nectar quality, as defined by both amino acids diversity and sugar ratios and concentration, will have a larger effect on bee visitation rates than other floral characteristics. I also hypothesized that an increase in soil fertility would increase pollen amino acid content and in turn bee visitation. I conducted two field experiments to test these hypotheses. In the first experiment, I observed four bee taxa (Honey bees, all Bumble bees excluding the species Bombus ternarius, the bumble bee species: Bombus ternarius, and all Other Bees) for visitation on four selected plant taxa (Bee’s friend [Phacelia tanacetifolia], Blanket flower [Gaillardia aristata], Borage [Borago officianalis, and Sunflower [Helianthus annuus ‘Zebulon’]) in four locations in Downeast Maine. Floral morphological characteristics and nutritional content of pollen and nectar were measured to determine which characteristics were correlated with bee visitation to flowers. I found that bees in different taxa foraged preferentially on one or several of our selected four species, but pollen amino acids and the floral traits measured were not factors influencing this visitation. In the second experiment, I varied soil fertility for jewelweed (Impatiens capensis) and measured subsequent floral production, flower morphological characteristics, pollen amino acids, and bumble bee visitation. I found that increased fertilizer did have a positive effect on plant growth, flower production, and amino acid content, which in turn positively influenced bumble bee visitation. The number of open flowers, and not amino acid content, was the consistent predictor of bee visitation to flowers