Publications by authors named "MacKinnon A"

Differences in the time of onset and magnitude of terminal decline were examined in three cognitive domains: processing speed, episodic memory, and global function. In addition, cognitive reserve was investigated by testing whether education affected the onset or rate of decline across these domains. Eight hundred ninety-six community-dwelling Australian adults aged ≥ 70 years were assessed up to four times over 12 years, with vital status followed for 17 years.

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We demonstrate the hohlraum radiation temperature and symmetry required for ignition-scale inertial confinement fusion capsule implosions. Cryogenic gas-filled hohlraums with 2.2 mm-diameter capsules are heated with unprecedented laser energies of 1.

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Background: 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.

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We report that the dominant human missense mutations G303E and G296S in GATA4, a cardiac-specific transcription factor gene, cause atrioventricular septal defects and valve abnormalities by disrupting a signaling cascade involved in endocardial cushion development. These GATA4 missense mutations, but not a mutation causing secundum atrial septal defects (S52F), demonstrated impaired protein interactions with SMAD4, a transcription factor required for canonical bone morphogenetic protein/transforming growth factor-β (BMP/TGF-β) signaling. Gata4 and Smad4 genetically interact in vivo: atrioventricular septal defects result from endothelial-specific Gata4 and Smad4 compound haploinsufficiency.

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Although elevated rates of parent psychosocial distress have been associated with child behavior and emotional problems, little is known about the nature of this relationship over time. This study followed an epidemiological cohort of children and adolescents over 11 years with 4 waves of data collection. Within this cohort, complete data were available on 238 mothers and their children.

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Thin-foil targets were irradiated with high-power (1 ≤ P(L) ≤ 210 TW), 10-ps pulses focused to intensities of I>10(18) W/cm(2) and studied with K-photon spectroscopy. Comparing the energy emitted in K photons to target-heating calculations shows a laser-energy-coupling efficiency to hot electrons of η(L-e) = 20 ± 10%. Time-resolved x-ray emission measurements suggest that laser energy is coupled to hot electrons over the entire duration of the incident laser drive.

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Background: Sub-threshold depression is common, impairs functioning, and increases the risk of developing major depression. Although psychological treatments have been investigated for sub-threshold depression, they are costly. A less costly alternative could be an educational health promotion campaign about effective self-help for depression symptoms.

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Purpose: Six previous reviews have found a relationship between depression and mortality. However, many past studies have failed to adequately control for the role of physical health. A proposed mechanism of the depression-mortality relationship suggests that physical health may mediate the relationship.

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Background: Paxillin is a modular protein that localises to cell adhesion sites where it facilitates bidirectional communication between the intracellular actin cytoskeleton and the extracellular matrix. These complex and dynamic interactions are essential for cell adhesion, cell migration and cell survival. The authors have previously demonstrated that paxillin is overexpressed in lung cancer tissues and identified somatic paxillin mutations in 9% of lung cancers.

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A gated x-ray detector is under development for use at the National Ignition Facility that is intended to provide plasma emission images in the presence of neutron yields up to 10(15) expected during inertial confinement fusion experiments with layered cryogenic targets. These images are expected to provide valuable time-resolved measurements of core and fuel symmetries. Additional capabilities of this instrument will include the ability to make spatially resolved electron temperature measurements.

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A temporally gated x-ray framing camera based on a proximity focus microchannel plate is one of the most important diagnostic tools of inertial confinement fusion experiments. However, fusion neutrons produced in imploded capsules interact with structures surrounding the camera and produce background to x-ray signals. To understand the mechanisms of this neutron induced background, we tested several gated x-ray cameras in the presence of 14 MeV neutrons produced at the Omega laser facility.

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In this paper we report on the radiography of a shock-compressed target using laser produced proton beams. A low-density carbon foam target was shock compressed by long pulse high-energy laser beams. The shock front was transversally probed with a proton beam produced in the interaction of a high intensity laser beam with a gold foil.

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Background And Purpose: Carotid IMT is widely used as a surrogate marker for atherosclerosis. Prospective studies in largely white populations demonstrate that it is strongly associated with carotid plaque and is an independent predictor of stroke. There are few data from black populations.

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Background: Multiple imputation (MI) is an advanced, principled method of dealing with missing data in statistical analyses, a common problem in medical research. This paper sought to document the use of MI in general medical journals and to evaluate the information provided to readers about the application of the procedure in studies.

Methods: Research articles using MI in analyses published in JAMA, New England Journal of Medicine, BMJ and the Lancet were identified using full text searches from the earliest date each journal offered such searches until the end of 2008.

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Background: Observational studies link low folate levels to depressive symptoms and to poor antidepressant medication response. Evidence supports a role for folate in potentiating the effect of antidepressant medications.

Aim: This prospective study examines the effects of folic acid+vitamin B12 supplementation and antidepressant medication in a community-based study of older adults with depressive symptoms.

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Introduction: Lung cancer is the commonest fatal malignancy in the developed world. Survival rates for lung cancer have not changed significantly over the past 30 years. Sources of data This report is a systematic review of the literature on our current understanding of lung cancer biology.

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Background: Few randomised controlled trials (RCTs) have examined potential preventive agents in high-risk community populations.

Aims: To determine whether a mental health literacy intervention, the promotion of physical activity, or folic acid plus vitamin B(12) reduce depression symptoms in community-dwelling older adults with elevated psychological distress.

Method: An RCT with a completely crossed 2 x 2 x 2 factorial design: (400 mcg/d folic acid + 100 mcg/d vitamin B(12) v.

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Background: Generalised anxiety disorder (GAD) is a high prevalence, chronic psychiatric disorder which commonly presents early in the lifespan. Internet e-health applications have been found to be successful in reducing symptoms of anxiety and stress for post traumatic stress disorder (PTSD), panic disorder, social phobia and depression. However, to date, there is little evidence for the effectiveness of e-health applications in adult GAD.

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The viability of fast-ignition (FI) inertial confinement fusion hinges on the efficient transfer of laser energy to the compressed fuel via multi-MeV electrons. Preformed plasma due to the laser prepulse strongly influences ultraintense laser plasma interactions and hot electron generation in the hollow cone of an FI target. We induced a prepulse and consequent preplasma in copper cone targets and measured the energy deposition zone of the main pulse by imaging the emitted K_{alpha} radiation.

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Defects in cardiac neural crest lead to congenital heart disease through failure of cardiac outflow tract and ventricular septation. In this report, we demonstrate a previously unappreciated role for the transcription factor Ets1 in the regulation of cardiac neural crest development. When bred onto a C57BL/6 genetic background, Ets1(-/-) mice have a nearly complete perinatal lethality.

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Background: Generalised Anxiety Disorder (GAD) is a highly prevalent psychiatric disorder. Effective prevention in young adulthood has the potential to reduce the prevalence of the disorder, to reduce disability and lower the costs of the disorder to the community. The present trial (the WebGAD trial) aims to evaluate the effectiveness of an evidence-based online prevention website for GAD.

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Background: Recent projections suggest that by the year 2030 depression will be the primary cause of disease burden among developed countries. Delivery of accessible consumer-focused evidenced-based services may be an important element in reducing this burden. Many consumers report a preference for self-help modes of delivery.

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Context: The use of antipsychotic medication for the prevention of psychotic disorders is controversial. Long-chain omega-3 (omega-3) polyunsaturated fatty acids (PUFAs) may be beneficial in a range of psychiatric conditions, including schizophrenia. Given that omega-3 PUFAs are generally beneficial to health and without clinically relevant adverse effects, their preventive use in psychosis merits investigation.

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We have recently shown that a study population of patients with at least 1 sessile serrated adenoma (SSA) are 4 times more likely to harbor synchronous serrated polyps [SSAs, traditional serrated adenomas (TSAs) and right sided hyperplastic polyps] than a unselected population of patients. However, 35% of the polyps in the study patients were conventional adenomas (CAds). We hypothesized that the CAds in these study patients would have histologic and molecular differences compared with CAds from a control population without sessile serrated adenomas.

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