An investigation of occupational stress in New Zealand dentists : a thesis presented in partial fulfilment of the requirements for the degree of Master of Arts in Psychology at Massey University

The present study sought to identify the occupational stressors as well as the resultant psychological and physical stress outcomes for New Zealand dentists. Additionally, the direct and moderating effects of coping were explored in relation to the identified stress outcomes. To achieve this, quantitative data was collected in the form of selfreport questionnaires, these being the Occupational Stress Inventory, the Suicide Probability Scale and the Dental Satisfaction Survey. A random, nationwide sample of 500 New Zealand dentists were sent these questionnaires, with 210 dentists returning completed questionnaires. The present study also sought to overcome recent criticisms of the methodology frequently used in stress research. As such qualitative data was collected through interviews with twelve New Zealand, general dentists in the Manawatu region. The interview questions were designed to elicit the job-specific stressors of dentistry in New Zealand as well as the coping responses of New Zealand dentists. Discussion with the New Zealand Dental Association confirmed that the quantitative sample in the present study is representative of the general New Zealand population. However, the representativeness of the qualitative sample could not be established due to the small sample size. The results of the present study showed that there was a consistent positive relationship between coping and job satisfaction, and a consistent negative relationship for coping and strain, and coping and suicide probability. Additionally, coping was found to be a moderator in the stressor-stress relationship, with dentists high in coping experiencing less distress (than dentists low in coping) in conditions of both high and low stress. Sex differences were found to be significant for the role overload stressor, with female dentists reporting on average significantly higher levels of role overload. Significant group differences were also found between self-employed and employee dentists, with employee dentists experiencing significantly greater levels of physical environment stress as well as stmin. Overall, low to moderate levels of stressors. coping, suicide probability, job satisfaction and physical/psychological distress were reported, indicating that New Zealand dentistry may not be any more stressful than other occupations in New Zealand. In terms of methodology, the present study indicates that the Occupational Stress Inventory, being a general stress self-report questionnaire, does not measure job-specific stressors. Therefore, it is suggested that future research utilises questionnaires that have been designed to measure specific occupational stressors as well as the frequency and the intensity of these stressors

Breaking the Cycle, Cholesterol Cycling, and Synapse Damage in Response to Amyloid-ß

Soluble amyloid-β (Aβ) oligomers, a key driver of pathogenesis in Alzheimer disease, bind to cellular prion proteins (PrPC) expressed on synaptosomes resulting in increased cholesterol concentrations, movement of cytoplasmic phospholipase A2 (cPLA2) to lipid rafts and activation of cPLA2. The formation of Aβ-PrPC-cPLA2 complexes was controlled by the cholesterol ester cycle. Thus, Aβ activated cholesterol ester hydrolases which released cholesterol from stores of cholesterol esters; the increased cholesterol concentrations stabilised Aβ-PrPC-cPLA2 complexes. Conversely, cholesterol esterification reduced cholesterol concentrations causing the dispersal of Aβ-PrPC-cPLA2. In cultured neurons, the cholesterol ester cycle regulated Aβ-induced synapse damage; inhibition of cholesterol ester hydrolases protected neurons, whereas inhibition of cholesterol esterification increased the Aβ-induced synapse damage. Here, I speculate that a failure to deactivate signalling pathways can lead to pathology. Consequently, the esterification of cholesterol is a key factor in the dispersal of Aβ-induced signalling platforms and synapse degeneration

Stellar and brown dwarf properties from numerical simulations

We review the statistical properties of stars and brown dwarfs obtained from the first hydrodynamical simulation of star cluster formation to produce more than a thousand stars and brown dwarfs while simultaneously resolving the lowest mass brown dwarfs (those with masses set by the opacity limit for fragmentation), binaries with separations down to 1 AU, and discs with radii greater than 10 AU. In particular, we present the eccentricity distribution of the calculation's very-low-mass and brown dwarf binaries which has not been previously published.Comment: To be published in Highlights of Astronomy, Vol 15 (CUP) from Special Session 7 of IAU XXVII. 2 pages, 1 table, 1 figure

Sir Henry Thomas De la Beche and the founding of the British Geological Survey

The founding of the Geological Survey by Henry De la Beche in 1835 is a key event in the history of British geology. Yet the Survey’s initiation actually began three years earlier when De la Beche secured financial assistance from the Board of Ordnance to map the geology of Devon at a scale of one inch to the mile. The British Geological Survey has thus been in existence for at least 175 years and can justly claim to be the world’s oldest continuously functioning geological survey organisation. There were early government-funded geological surveys also in France, the United States, Ireland and Scotland. De la Beche’s notable success both in launching and sustaining the Geological Survey demanded a good deal of diplomacy, determination and deviousness! Even so, the Survey was nearly brought to an untimely end in 1837 when De la Beche was publicly criticised for his interpretation, based on lithology and field relations, of the difficult Culm strata of north Devon. The resolution of the ‘Devonian Controversy’ led to a fundamental change in geological practice, in which the value of fossils as stratigraphic markers, founded on an acceptance of organic change over time, was established beyond question. Fortunately the Survey survived its early trauma and De la Beche went on to extend his influence with the expansion of the Museum of Economic Geology (also formed in 1835), and the establishment of the Mining Record Office and the School of Mines

Collapse of a Molecular Cloud Core to Stellar Densities: The First Three-Dimensional Calculations

We present results from the first three-dimensional calculations ever to follow the collapse of a molecular cloud core (~ 10^{-18} g cm^{-3}) to stellar densities (> 0.01 g cm^{-3}). The calculations resolve structures over 7 orders of magnitude in spatial extent (~ 5000 AU - 0.1 R_\odot), and over 17 orders of magnitude in density contrast. With these calculations, we consider whether fragmentation to form a close binary stellar system can occur during the second collapse phase. We find that, if the quasistatic core that forms before the second collapse phase is dynamically unstable to the growth of non-axisymmetric perturbations, the angular momentum extracted from the central regions of the core, via gravitational torques, is sufficient to prevent fragmentation and the formation of a close binary during the subsequent second collapse.Comment: ApJ Letters, in press (will appear in Nov 20 issue; available from the ApJ Rapid Release web page). 7 pages, incl. 5 figures. Also available at http://www.mpia-hd.mpg.de/theory/bat

Precious?

The costume industry regularly utilizes vintage clothing for performance in theatre and film. Reflecting on garments previously encountered during a career in this industry, the authors contemplate the lives and purpose of such items and their role within a working costume store. Discussion with professionals from various backgrounds evokes a wide range of questions and differing opinions surrounding the idea of value in this context, producing a subjective reaction with no definitive answer. This article contextualizes these questions through the study of a single item of historical clothing currently used as costume, encouraging the reader to consider how the value of such pieces is perceived. The concept of the costume stock room as an accessible, living archive is explored in relation to the recognized traditional archival structure of a museum store where conservation and preservation have priority

cAMP-Inhibits Cytoplasmic Phospholipase A(2) and Protects Neurons against Amyloid-beta-Induced Synapse Damage

A key event in Alzheimer’s disease (AD) is the production of amyloid-β (Aβ) peptides and the loss of synapses. In cultured neurons Aβ triggered synapse damage as measured by the loss of synaptic proteins. α-synuclein (αSN), aggregates of which accumulate in Parkinson’s disease, also caused synapse damage. Synapse damage was associated with activation of cytoplasmic phospholipase A2 (cPLA2), an enzyme that regulates synapse function and structure, and the production of prostaglandin (PG) E2. In synaptosomes PGE2 increased concentrations of cyclic adenosine monophosphate (cAMP) which suppressed the activation of cPLA2 demonstrating an inhibitory feedback system. Thus, Aβ/αSN-induced activated cPLA2 produces PGE2 which increases cAMP which in turn suppresses cPLA2 and, hence, its own production. Neurons pre-treated with pentoxifylline and caffeine (broad spectrum phosphodiesterase (PDE) inhibitors) or the PDE4 specific inhibitor rolipram significantly increased the Aβ/αSN-induced increase in cAMP and consequently protected neurons against synapse damage. The addition of cAMP analogues also inhibited cPLA2 and protected neurons against synapse damage. These results suggest that drugs that inhibit Aβ-induced activation of cPLA2 and cross the blood–brain barrier may reduce synapse damage in AD