Quantum Interference and Inelastic Scattering in a Model Which-Way Device

A which-way device is one which is designed to detect which of 2 paths is taken by a quantum particle, whether Schr\"odinger's cat is dead or alive. One possible such device is represented by an Aharonov-Bohm ring with a quantum dot on one branch. A charged cantilever or spring is brought close to the dot as a detector of the presence of an electron. The conventional view of such a device is that any change in the state of the cantilever implies a change in the electron state which will in turn destroy the interference effects. In this paper we show that it is in fact possible to change the state of the oscillator while preserving the quantum interference phenomenon.Comment: 5 pages, 7 figures, Localisation 2002 Toky

How much high school maths do students need to succeed at university physics?

BACKGROUND Most first-year calculus-based Physics courses offered at Australian Universities have prerequisites which include Year 12 Physics and typically two Mathematics subjects. An increasing number of students are attempting these Physics courses without the full mathematics pre-requisite. AIMS To determine if attempting a calculus-based Physics course without having the full mathematical perquisites impacts on a student’s performance within that course, progression and success in later Physics courses. METHOD At the University of Adelaide the ideal mathematical pre-requisites for Physics-IA (a calculus-based course) are the Year 12 SACE subjects: Mathematical Studies and Specialist Mathematics. However an increasing number of students are attempting this course without Specialist Mathematics. In 2014, 25% of the school-leaving students enrolled in Physics-IA had only completed Mathematical Studies and not Specialist Mathematics. This corresponds with a period over the last several years where the number of students completing Year 12 SACE Physics has remained constant but the numbers completing Mathematical Studies and Specialist Mathematics has declined. The correlation between the reduction in the number of students completing the above Year 12 Maths subjects and reduction in the number of students who attempt Physics IA without the full mathematical pre-requisites has been examined using student enrolment from 2003 to 2014. The difference in the success of students who attempt calculus-based Physics with and without the desired mathematical preparation has been analysed using enrolments from 2003 until 2014 in the following way: • Success (grade obtained) in the first semester course Physics IA, • Progression and success in Physics IB (semester 2 course). • Progression and success in Second Year Physics courses. RESULTS and CONCLUSIONS Results and conclusion will be presented in detail at the conference

A feasibility study of team-based primary care for chronic disease management training in rural Australia

Increasing rates of chronic disease management (CDM) are projected to contribute to significant effective shortfalls in the primary care workforce in Australia.1 Additionally, rural Australia carries a higher burden of chronic illness2 and has existing medical workforce shortages.3 Therefore, it is imperative that rural primary care maximises the efficiency of the CDM it provides

Evaluation of a workplace suicide prevention program in the Australian manufacturing industry : protocol for a cluster-randomised trial of MATES in manufacturing

Males are at higher risk of death by suicide than females in Australia, and among men, blue-collar males are at higher risk compared to other working males. In response, MATES in Construction developed a workplace suicide prevention program for the construction sector in 2007 that has been widely implemented in Australia. In the current project, this program is being adapted and trialled in the manufacturing sector. The common aims of MATES programs are to improve suicide prevention literacy, help-seeking intentions, and helping behaviours. The program will be evaluated using a cluster randomised-controlled trial design with waitlist controls across up to 12 manufacturing worksites in Australia. We hypothesise that after 8 months of the MATES in Manufacturing program, there will be significantly greater improvements in help-seeking intentions (primary outcome) compared to waitlist controls. The project is led by Deakin University in collaboration with the University of Melbourne, and in partnership with MATES in Construction and a joint labour-management Steering Group. Trial registration: The trial was registered retrospectively with the Australian New Zealand Clinical Trials Registry on 25 January 2022 (ACTRN12622000122752)

The effectiveness of simple psychological and exercise interventions for high prevalence mental health problems in young people: a factorial randomised controlled trial

<p>Abstract</p> <p>Background</p> <p>The prevalence of mental illness in young people is the highest of any age group, with the onset of depression, anxiety and substance use peaking between 18 and 24 years. Effective treatments that target sub-threshold or mild to moderate levels of disorder in young people are required to reduce the risk of persistence and recurrence. The aims of this study are to evaluate whether treatments that are less intensive than cognitive-behaviour therapy, such as problem solving therapy and exercise treatments, are acceptable and effective in managing depression and anxiety symptoms in young people and to identify possible attributes in those who are likely to respond to these treatments.</p> <p>Methods/design</p> <p>This is a factorial randomised controlled trial conducted at a large, metropolitan youth mental health service. Participants are young help-seekers aged 15-25 years with sub-threshold or mild to moderate levels of depression and anxiety (with or without comorbid substance use). The interventions comprise 4 treatment combinations delivered by psychologists over 6 sessions on a weekly basis: a psychological intervention (problem solving therapy versus supportive counselling) and an exercise intervention (behavioural exercise versus psychoeducation). Structured assessments occur at baseline, mid-point, end-point (6 weeks) and at a 6- and 12-month follow-up. The primary outcomes are depression and anxiety symptoms as measured by the Beck Depression and Anxiety Inventories. Secondary outcomes include remission (defined as no longer meeting the diagnostic criteria for a disorder if threshold level was reached at baseline, or no longer scoring in the clinical range on scale scores if sub-threshold at baseline), substance use, and functioning.</p> <p>Discussion</p> <p>The effectiveness of less complex psychological and exercise interventions in young help-seekers with sub-threshold or mild to moderate presentations of high prevalence disorders is yet to be explored. This study has been designed to examine the effectiveness of these interventions delivered alone, or in combination, in a youth-specific service. If effective, the interventions have the potential to prevent the progression of early symptoms and distress to later and potentially more serious stages of mental disorder and reduce the likelihood of ongoing problems associated with the risk of persistence and recurrence.</p> <p>Trial registration</p> <p>Australian New Zealand Clinical Trials Registry <a href="http://www.anzctr.org.au/ACTRN12608000550303.aspx">ACTRN12608000550303</a></p

Predicting Dementia in Cerebral Small Vessel Disease Using an Automatic Diffusion Tensor Image Segmentation Technique.

Background and Purpose- Cerebral small vessel disease (SVD) is the most common cause of vascular cognitive impairment, with a significant proportion of cases going on to develop dementia. We explore the extent to which diffusion tensor image segmentation technique (DSEG; which characterizes microstructural damage across the cerebrum) predicts both degree of cognitive decline and conversion to dementia, and hence may provide a useful prognostic procedure. Methods- Ninety-nine SVD patients (aged 43-89 years) underwent annual magnetic resonance imaging scanning (for 3 years) and cognitive assessment (for 5 years). DSEG-θ was used as a whole-cerebrum measure of SVD severity. Dementia diagnosis was based Diagnostic and Statistical Manual of Mental Disorders V criteria. Cox regression identified which DSEG measures and vascular risk factors were related to increased risk of dementia. Linear discriminant analysis was used to classify groups of stable versus subsequent dementia diagnosis individuals. Results- DSEG-θ was significantly related to decline in executive function and global cognition (P<0.001). Eighteen (18.2%) patients converted to dementia. Baseline DSEG-θ predicted dementia with a balanced classification rate=75.95% and area under the receiver operating characteristic curve=0.839. The best classification model included baseline DSEG-θ, change in DSEG-θ, age, sex, and premorbid intelligence quotient (balanced classification rate of 79.65%; area under the receiver operating characteristic curve=0.903). Conclusions- DSEG is a fully automatic technique that provides an accurate method for assessing brain microstructural damage in SVD from a single imaging modality (diffusion tensor imaging). DSEG-θ is an important tool in identifying SVD patients at increased risk of developing dementia and has potential as a clinical marker of SVD severity

Momentum Flux Spectra of a Mountain Wave Event Over New Zealand

During the Deep Propagating Gravity Wave Experiment (DEEPWAVE) 13 July 2014 research flight over the South Island of New Zealand, a multiscale spectrum of mountain waves (MWs) was observed. High-resolution measurements of sodium densities were available from ~70 to 100 km for the duration of this flight. A comprehensive technique is presented for obtaining temperature perturbations, T′, from sodium mixing ratios over a range of altitudes, and these T′ were used to calculate the momentum flux (MF) spectra with respect to horizontal wavelengths, λH, for each flight segment. Spectral analysis revealed MWs with spectral power centered at λH of ~80, 120, and 220 km. The temperature amplitudes of these MWs varied between the four cross-mountain flight legs occurring between 6:10UT and 9:10UT. The average spectral T′ amplitudes near 80 km in altitude ranged from 7–13 K for the 220 km λH MW and 4–8 K for the smaller λH MWs. These amplitudes decayed significantly up to 90 km, where a critical level for MWs was present. The average MF per unit mass near 80 km in altitude ranged from ~13 to 60 m2/s2 across the varying spectra over the duration of the research flight and decayed to ~0 by 88 km in altitude. These MFs are large compared to zonal means and highlight the importance of MWs in the momentum budget of the mesosphere and lower thermosphere at times when they reach these altitudes

Change in multimodal MRI markers predicts dementia risk in cerebral small vessel disease.

OBJECTIVE: To determine whether MRI markers, including diffusion tensor imaging (DTI), can predict cognitive decline and dementia in patients with cerebral small vessel disease (SVD). METHODS: In the prospective St George's Cognition and Neuroimaging in Stroke study, multimodal MRI was performed annually for 3 years and cognitive assessments annually for 5 years in a cohort of 99 patients with SVD, defined as symptomatic lacunar stroke and confluent white matter hyperintensities (WMH). Progression to dementia was determined in all patients. Progression of WMH, brain volume, lacunes, cerebral microbleeds, and a DTI measure (the normalized peak height of the mean diffusivity histogram distribution) as a marker of white matter microstructural damage were determined. RESULTS: Over 5 years of follow-up, 18 patients (18.2%) progressed to dementia. A significant change in all MRI markers, representing deterioration, was observed. The presence of new lacunes, and rate of increase in white matter microstructural damage on DTI, correlated with both decline in executive function and global functioning. Growth of WMH and deterioration of white matter microstructure on DTI predicted progression to dementia. A model including change in MRI variables together with their baseline values correctly classified progression to dementia with a C statistic of 0.85. CONCLUSIONS: This longitudinal prospective study provides evidence that change in MRI measures including DTI, over time durations during which cognitive change is not detectable, predicts cognitive decline and progression to dementia. It supports the use of MRI measures, including DTI, as useful surrogate biomarkers to monitor disease and assess therapeutic interventions

Progression of MRI markers in cerebral small vessel disease: sample size considerations for clinical trials.

Detecting treatment efficacy using cognitive change in trials of cerebral small vessel disease (SVD) has been challenging, making the use of surrogate markers such as magnetic resonance imaging (MRI) attractive. We determined the sensitivity of MRI to change in SVD and used this information to calculate sample size estimates for a clinical trial. Data from the prospective SCANS (St George's Cognition and Neuroimaging in Stroke) study of patients with symptomatic lacunar stroke and confluent leukoaraiosis was used (n=121). Ninety-nine subjects returned at one or more time points. Multimodal MRI and neuropsychologic testing was performed annually over 3 years. We evaluated the change in brain volume, T2 white matter hyperintensity (WMH) volume, lacunes, and white matter damage on diffusion tensor imaging (DTI). Over 3 years, change was detectable in all MRI markers but not in cognitive measures. WMH volume and DTI parameters were most sensitive to change and therefore had the smallest sample size estimates. MRI markers, particularly WMH volume and DTI parameters, are more sensitive to SVD progression over short time periods than cognition. These markers could significantly reduce the size of trials to screen treatments for efficacy in SVD, although further validation from longitudinal and intervention studies is required.Journal of Cerebral Blood Flow & Metabolism advance online publication, 3 June 2015; doi:10.1038/jcbfm.2015.113