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Whole genome amplification and its impact on CGH array profiles
No full textBackground: Some array comparative genomic hybridisation (array CGH) platforms require a minimum of micrograms of DNA for the generation of reliable and reproducible data. For studies where there are limited amounts of genetic material, whole genome amplification (WGA) is an attractive method for generating sufficient quantities of genomic material from miniscule amounts of starting material. A range of WGA methods are available and the multiple displacement
amplification (MDA) approach has been shown to be highly accurate, although amplification bias has been reported. In the current study, WGA was used to amplify DNA extracted from whole blood. In total, six array CGH experiments were performed to investigate whether the use of whole genome amplified DNA (wgaDNA) produces reliable and reproducible results. Four experiments were conducted on amplified DNA compared to unamplified DNA and two experiments on unamplified DNA compared to unamplified DNA. Findings: All the experiments involving wgaDNA resulted in a high proportion of losses and gains of genomic material. Previously, amplification bias has been overcome by using amplified DNA in both the test and reference DNA. Our data suggests that this approach may not be effective, as the gains and losses introduced by WGA appears to be random and are not reproducible between different experiments using the same DNA. Conclusion: In light of these findings, the use of both amplified test and reference DNA on CGH arrays may not provide an accurate representation of copy number variation in the DNA
The Costs of Confronting Osteoporosis: Cost Study of an Australian Fracture Liaison Service
No full textFracture liaison services (FLS) are an accepted approach to lowering rates of osteoporotic refractures. However, resource allocations to FLS are open to challenge, as most relevant cost analyses are based on anticipated, rather than observed, benefits. To support informed decision making, we have estimated the cost of operating an FLS, from the perspective of the Australian health system, with real life costs. On the basis of hospital records, we compared total costs of two cohorts of patients presenting with minimal trauma fractures (MTFs) at two hospital emergency departments (EDs) across a 6-month period (July to December 2010). The treatment cohort (FLS Cohort, n = 515) attended an ED at a hospital offering FLS post-fracture care; the Usual Care Cohort (n = 416) attended an ED at a hospital without an FLS. Hospital records were reviewed for further attendance of both groups at their respective hospitals’ EDs with refractures for the subsequent 3 years. Costs were constructed from “bottom up” with a “microcosting” approach. Total costs for both cohorts included any FLS and the costs of refractures. Cohort costs were estimated for every 1000 patients over the 3 observed years. Compared with the Usual Care Cohort, the FLS Cohort had 62 fewer fractures per 1000 patients and 880,154. As both hospitals consistently process around 2000 patients per year, the estimated annual saving is 1.8 million (Australian dollars). From the perspective of the Australian public health system, investment in FLS can be a financially effective way of reducing the cost of osteoporotic fracture management. © 2018 The Authors JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research
The invisible influence
No full textIn a rare look behind the scenes of sponsored medical education, the Australian Broadcasting Corporation’s Background Briefing programme will this weekend show that it is not uncommon for drug company sponsors to suggest speakers at sessions that are assumed by the thousands of general practitioners who attend them to be totally independent. The evidence, such as it is, tentatively indicates that the prescribing habits of doctors may be affected by attending sponsored educational events, albeit only in the short term. Perhaps the recent revelations from Australia—and confirmation from the industry itself that it is “not unusual” for sponsors to suggest speakers—will sharpen the lines of debate about how to achieve more independent education or at least greater transparency
Electromagnetic wave propagation along conductors parallel to interfacing homogeneous half spaces
No full textThis thesis explores electromagnetic wave propagation along single and multi-conductor systems consisting of bare and insulated wires located arbitrarily on either side of interfacing homogeneous half spaces. Equations are derived from first principles to predict the behavior of such systems across the full electromagnetic spectrum. The proposed full spectrum equations extend existing theory to include magnetizable earth and conductors with finite conductivity. They also offer a full spectrum solution for the excitation of conductors located either side of the interfacing half spaces for the first time in published literature. The proposed full spectrum equations are limited to homogeneous earth, and bare and insulated cylindrical conductors but remain general in every other sense. Novel expressions for the continuous modes of the systems have also been developed from these equations. Numerical investigation of the proposed full spectrum equations identifies numerous new discrete modes of propagation for single conductor systems, several with very low attenuation constants that may have industrial application. The modes associated with the full spectrum performance of two conductor systems consisting of parallel conductors located arbitrarily across the interface between the homogeneous half spaces energised by a delta-gap voltage source has been investigated in detail for the first time. Based on the numerical results conditions for which the full spectrum system performance may be approximated by the discrete Transmission Line mode are considered. The proposed full spectrum equations are shown to reduce to the quasi-TEM mode approximations that are Carson and Pollaczek's original solutions to the problem, bringing the understanding of the quasi-TEM mode approximations in line with the full spectrum solutions so that it may be adequately applied to power system safety. The conditions under which this may occur are clearly documented. Alternate quasi-TEM mode approximations are proposed in an analytical form. The assumptions required to reduce these alternate quasi-TEM mode approximations to Carson and Pollaczek's original solutions are detailed, making them, for the first time, a full set of analytical equations that are exact solutions to Carson and Pollaczek's equations. The analytical solutions provide the benefit of improved stability and reduced computation time with respect to numerical calculations
Binding of chlorinated phenylacrylonitriles to the aryl hydrocarbon receptor: computational docking and molecular dynamics simulations
No full textThe development of ligands capable of binding to the aryl hydrocarbon receptor (AhR) and hijacking its signaling pathway is of potential use for the design of novel agents against breast cancer. To guide the synthesis of new compounds and characterize their binding to the AhR, we employed homology modeling, ligand docking, and molecular dynamics simulations. As there is currently no crystallographic information available for the structure of the AhR’s ligand-binding PAS-B domain, a homology model was developed. The location of the binding site was identified by scanning the model for concave areas and comparing them to known ligand-binding sites in proteins related to the AhR, such as the CLOCK:BMAL1 transcriptional activator complex and the hypoxia-inducible factor-2α (HIF-2α). Docking of several chlorinated phenylacrylonitriles was performed with the modeling suite MOE, identifying π-π stacking, hydrophobic, and van der Waals interactions as the driving forces for binding, an observation consistent with the hydrophobic nature of the site. Molecular dynamics simulations with one of the compounds for 100 ns verified the overall stability of a docking-predicted pose and revealed the presence of interacting water molecules in the vicinity of the ligand. Given the buried location of the ligand in the core of the receptor, this observation was somewhat unexpected, but it explained a slight shift of the ligand pose seen during the simulation
Chinese research students' adjustment to the Australian learning environment
No full textThis paper reports on a pilot study conducted at the University of Newcastle, Australia, seeking to identify clearly the cultural dimension of teaching-learning difficulties encountered by Ph.D. candidates of Chinese cultural heritage during their research training. The cultural values implied by two educational systems in China and Australia were compared and analyzed in order to identify the communication barriers that may exist between students and supervisors, and which may negatively affect research performance
The evolution of entertainment news: “Entertainment Tonight’s” legacy to news programs and media culture
No full textThis essay considers the impact the television news program Entertainment Tonight had on the news industry and popular culture’s appeal in society from its inception in 1981. ET defined a style of news coverage and helped draw in and maintain the audience for entertainment news that in turn affected how news outlets worldwide viewed entertainment and where it fit into programming, society and culture today. This is chronicled through interviews with the original creators, producers and writers of ET as well as news directors and producers who remember and reflect on the impact this entertainment news program had on the news media and entertainment culture. Sara Magee is Assistant Professor of Communications at Loyola University, Maryland
Non-specialist teachers' confidence to teach PE: the nature and influence of personal school experiences in PE
No full textBackground: Over the past 20 years, a number of researchers have expressed concern over the lack of
confidence and qualifications of primary school teachers to teach PE. Evidently, the influence of
personal school PE experiences may play an important role in the development of teachers’
confidence to appropriately teach PE. Most research that has examined the effects of
biographical experiences in PE on teachers’ confidence to teach PE has focused on specialists,
rather than non-specialist PE teachers. Purpose: Two major aims of this study were: (i) to examine the nature of personal school experiences of non-specialist preservice and inservice primary teachers and, importantly, the influence of these experiences on their PE teaching confidence; and (ii) to analyse the reasons provided by teachers to explain their level of PE teaching confidence. No studies to date have attempted to test a theoretical
causal model of this nature using PE teaching confidence as the key dependent variable and personal
school experiences in PE as mediating variables. Participants and setting: Quantitative data were collected from non-specialist preservice teachers in Years 2, 3 and 4 of preservice education (n = 386) and inservice (n = 53) primary teachers in New South Wales (NSW), Australia. The student teacher sample consisted of students studying
a double degree majoring in primary education in the second (n = 143), third (n= 127), or
fourth year (n = 116) of their higher education at a NSW tertiary institution. Inservice teachers
were randomly selected from NSW primary schools from both the state school system and nonstate
school system. In total, 53 inservice teachers were included from 37 different schools.
Research design: Employed a non-experimental correlational research design with Confidence
Teaching PE as the key dependent variable. Data collection: Largely quantitative data were collected via the administration of a questionnaire which utilised both select-response and open-ended questions.
Data analysis: One-factor congeneric measurement models were utilised in this study to produce
estimates of constructs for primary and secondary school PE experiences and commitment to
sport and physical activity. Self-perceived levels of confidence were also assessed in the teaching
of 10 PE content areas. Hypothesised relationships between key variables were tested using
multilevel structural equation modelling techniques. Findings: Many respondents’ PE experiences included programs that lacked variety and frequency of
delivery, were dominated by involvement in ‘supervised’ games and involved little teaching and
learning. Individuals who recalled more negative experiences in school PE were less likely to be
involved in physical activity and indicated lower levels of PE teaching confidence than those who
had more favourable experiences. Respondents held only a ‘moderate’ level of confidence in their
PE teaching abilities. Results indicated that the quality of an individual’s school PE experiences
directly predicted his or her confidence to teach PE (variance explained = 30%). It was apparent
that many of the reasons provided for a lack of confidence were based on memories of poor
quality school PE.
Conclusions/Recommendations: To prevent the perpetuation of a non-teaching ideology or the
decision by many teachers to avoid teaching PE, teacher educators must look to incorporate
biographical analysis (including reflection sessions, group work, values clarification activities,
portfolios) and opportunities for PE teaching as part of preservice courses. Teacher educators
may need to make students become dissatisfied and disgruntled with perpetuating their previous
negative or non-teaching experiences, providing them with more appropriate conceptions.
Teacher educators may use this information to design more relevant courses incorporating
meaningful learning experiences. Strategies employed at the tertiary level, such as increased
opportunities to improve mastery expectations, should be complemented with relevant and
purposeful professional development for all classroom teachers
Pollution deposition rates on insulator (HV) surfaces for use in atmospheric corrosivity estimation
No full textThis work reports the deposition onto high voltage insulators and correlation to atmospheric corrosivity measurement. This work includes corrosion studies at 15 sites in New Zealand (1,816 tests) for in excess of 12 months, and co-operative research in South Africa. In addition, to confirm the relevance and transportability of this proposed model, a review of the published international data on deposition rates on insulators was conducted. It was noted that the deposition rate of airborne pollutants onto a surface is dependent upon the true surface area facing the wind and the aerodynamic properties of the surface. Such is the effect that surfaces with minimal exposure to the wind such as horizontal plates, have been shown to be poor collectors of deposits while vertical plates are more efficient, followed by high voltage glass insulators, the ISO9223 salt candle, and the largest collector is the Direct Dust Deposit Gauge. This study found that the ISO9223 wet salt candle and the average annual deposition rate on the High Voltage Glass insulator bottom surface (unenergized) provided relatively similar deposition results. The deposition onto insulator surfaces may be a more relevant method as it replicates deposition on large surfaces. This Equivalent Salt Dry Deposition (ESDD) method for HV insulators is an all inclusive measure of the airborne pollutants deposition rate and converts the total deposited material into a single value equivalent to that of salt, even though the deposit may consist of sulphur, marine salts, nitrates, and other conductive pollutants. The measured deposition rate on the sheltered insulator bottoms at 85 sites around the world predicted 87% of the ISO corrosivity categories (based on zinc corrosion) for these sites. Results from equatorial Asia appear to be non-compliant and warrant further investigation. The ESDD values are now being quoted from around the world, by electrical engineers who use the recently revised CIGRE methodology, to determine the probability of arc-over (shorting to earth) of high voltage cables due to pollution build-up on insulators. The implications from this research are significant, with the cost of atmospheric corrosivity studies becoming prohibitively expensive, this method converts technically valid surface deposition results from the electrical engineers from around the world (provided at no cost), to valid empirical corrosivity rates from often remote locations
The sedimentology and tsunamigenic potential of the byron submarine landslide off New South Wales, Australia
No full textExtensive evidence for submarine landslide failure is found along the east Australian continental margin. This paper assesses the sedimentological properties and models the failure event that created the Byron landslide scar, located on the SE Australian continental margin, c. 34 km off the coast of Byron Bay, New South Wales. Sedimentological analyses and dating (radiocarbon and biostratigraphic) were conducted on three gravity cores collected from within the Byron landslide scar. A paraconformity, identified in one of the three cores by a distinct colour change, was found to represent a distinct radiocarbon age gap of at least 25 ka and probably represents the detachment surface of the slide plane. The core-derived sediment properties for the Byron landslide scar were used to inform hydrodynamic modelling using the freely available numerical modelling software, Basilisk. Model results highlight the important role of sediment rheology on the tsunamigenic potential of the slide and on the resulting inundation along the east Australian coastline, therefore providing a greater understanding of the modern hazard posed by comparable future submarine landslide events for the east Australian coastline