Junior Recital: Amy Lloyd, Flute

Kemp Recital Hall Thursday Evening April 20, 1995 5:30p.m

The influence of binarity on the morpho-kinematics of planetary nebulae

The role of central star binarity in the shaping of planetary nebulae (PNe) has been the subject of much debate, with single stars believed to be incapable of producing the most highly collimated morphologies. However, observational support for binary-induced shaping has been sadly lacking. Here, we highlight the results of a continuing programme to spatio-kinematically model the morphologies of all PNe known to contain a close binary central star. Spatio-kinematical modelling is imperative for these objects, as it circumvents the degeneracy between morphology and orientation which can adversely affect determinations of morphology based on imaging alone. Furthermore, spatio-kinematical modelling accurately determines the orientation of the nebular shell, allowing the theoretically predicted perpendicular alignment, between nebular symmetry axis and binary orbital plane, to be tested. To date, every PN subjected to this investigation has displayed the predicted alignment, indicating that binarity has played an important role in the formation and evolution of these nebulae. The further results from this programme will be key, not only in determining whether binary interaction is responsible for shaping the studied PNe, but also in assessing the importance of binarity in the formation and evolution of all PNe in general.Comment: 2 pages, 2 tables, proceedings of the IAU Symposium No. 283, Planetary Nebulae: An Eye to the Futur

The proteomic landscape of microglia in health and disease

Microglia are the resident immune cells of the central nervous system (CNS) and as such play crucial roles in regulating brain homeostasis. Their presence in neurodegenerative diseases is known, with neurodegeneration-associated risk genes heavily expressed in microglia, highlighting their importance in contributing to disease pathogenesis. Transcriptomics studies have uncovered the heterogeneous landscape of microglia in health and disease, identifying important disease-associated signatures such as DAM, and insight into both the regional and temporal diversity of microglia phenotypes. Quantitative mass spectrometry methods are ever increasing in the field of neurodegeneration, utilised as ways to identify disease biomarkers and to gain deeper understanding of disease pathology. Proteins are the main mechanistic indicators of cellular function, yet discordance between transcript and proteomic findings has highlighted the need for in-depth proteomic phenotypic and functional analysis to fully understand disease kinetics at the cellular and molecular level. This review details the current progress of using proteomics to define microglia biology, the relationship between gene and protein expression in microglia, and the future of proteomics and emerging methods aiming to resolve heterogeneous cell landscapes

A study of the kinematics and binary-induced shaping of the planetary nebula HaTr 4

We present the first detailed spatio-kinematical analysis and modelling of the planetary nebula HaTr 4, one of few known to contain a post-common-envelope central star system. Common envelope evolution is believed to play an important role in the shaping of planetary nebulae, but the exact nature of this role is yet to be understood. High spatial- and spectral- resolution spectroscopy of the [OIII]5007 nebular line obtained with VLT-UVES are presented alongside deep narrowband Ha+[NII]6584 imagery obtained using EMMI-NTT, and together the two are used to derive the three-dimensional morphology of HaTr 4. The nebula is found to display an extended ovoid morphology with an enhanced equatorial region consistent with a toroidal waist - a feature believed to be typical amongst planetary nebulae with post-common-envelope central stars. The nebular symmetry axis is found to lie perpendicular to the orbital plane of the central binary, concordant with the idea that the formation and evolution of HaTr 4 has been strongly influenced by its central binary.Comment: 9 pages, 5 figures, accepted for publication in MNRA

Sound Over Troubled Waters: Noise Pollution in Prek Toal, Cambodia

Environmental noise pollution, or excessive noise related to machinery operation and vehicular transportation, is a common problem in urban environments. Less understood is the effect that chronic environmental noise can have in rural environments, where there is greater potential for disruption of native ecosystems and the quality of life in small villages. Chronic exposure to noises above 85 decibels causes noise induced hearing loss (NIHL) in humans, which has irreversible effects. But even less understood is the effect that chronic noise can have on animals that thrive in less urbanized environments. Here, I examine the effect of noise pollution caused by motor boats in the floating village of Prek Toal, Cambodia. I identify the types of motorboats used along the Sangker river, the river that runs through the village, and experimentally measure their maximum sound intensities across a various distances from 0-100m from the motor. The effect of the noise on the boat is examined to address the occupational hazard to the driver. The observational data is also used to derive an empirical equation for sound decay that is specific to this rural environment. This equation is used to map the spatial distribution of environmental noise pollution within the village and identify zones of noise induced hearing loss along the Sangker river. A total of sixty villagers were surveyed to identify the types of motors present in Prek Toal. The two major motor companies, Yokohama and Hinota, offer motors with a wide range of horsepower. Sound intensity measurements revealed the mean range of sound that drivers are exposed to is 93 dB(A) to 112 dB(A), with the majority of motors above 100 dB(A)s. This exceeds the minimum for NIHL, demonstrating that drivers in Prek Toal are exposed to hearing-related occupational hazards while driving. The empirically derived sound decay equation reveals an exponential relationship between sound and distance in Prek Toal. This relationship matches what has been found in other studies. A spatial analysis of the observational data reveal that each boat has a minimum NIHL radius of 45 meters

Prohibiting public drinking in an urban area: determining the impacts on police, the community and marginalised groups

With public drinking laws proliferating across urban areas over the past 15 years, this project evaluated the implementation of these laws, their effectiveness, and their impact on a range of target groups including police, residents, traders, local health and welfare workers, and potentially marginalised groups. Overview Public drinking laws have proliferated across urban areas over the past 15 years; however, there have been very few evaluations of their impacts and effectiveness. The purpose of this project was to evaluate public drinking laws across three diverse inner-urban local government areas (LGAs) of Melbourne: the Cities of Yarra, Darebin and Maribyrnong. The objectives of this project were to evaluate the implementation of public drinking laws, the effectiveness of these laws and the impact of these laws on a range of target groups including police, residents, traders, local health and welfare workers, and potentially marginalised groups. The evaluation produced equivocal findings in relation to whether public drinking laws reduced congregations of drinkers (with differing findings across municipalities) and there was no evidence that these laws reduced alcohol-related crime or harm. However, public drinking laws do make residents feel safer and improve the amenity of an area from the perspective of residents and traders. The evaluation found that public drinking laws often result in negative impacts to marginalised individuals and this requires more consideration in the implementation and enforcement of these laws. It is important that public drinking laws are carefully considered, implemented and enforced (with local council officers and police liaising collaboratively to respond to the needs of the individual community) and are coupled with community-specific social inclusion strategies