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Previous research demonstrates various associations between depression, cardiovascular disease (CVD) incidence and mortality. Differences between studies may occur as a result of different methodologies.
This work investigated the impact of using two different methods to measure depression and two different methods of analysis to establish relationships.
The work investigated the association between depression, CVD incidence (CVDI) and mortality from coronary heart disease (MCHD), smoking related conditions (MSRC), and all causes (MALL), in a major population study using depression measured from a validated scale and a depression measure derived by factor analysis, and analyses based on continuous data and grouped data.
Data from the PRIME Study (N=9,798 men) on depression and ten year CVD incidence and mortality were analysed using Cox proportional hazards models.
Using continuous data, no relationships with CVDI were found, but both measures of depression resulted in the emergence of positive associations between depression and mortality (MCHD, MSRC, MALL). Using grouped data, no associations with CVDI or MCVD were found, and associations between the measure derived from factor analysis and MSRC and MALL were also lost. Positive associations were only found between depression measured using validated items, MSRC and MALL.
These data demonstrate a possible association between depression and mortality but detecting this association is dependent on the methodology used. Different findings based on methodology present clear problems for the determination of relationships. The differences here suggest the preferential use of validated scales and suggest against over-reduction via factor analysis and grouping.
EMU is a wide-field radio continuum survey planned for the new Australian Square Kilometre Array Pathfinder (ASKAP) telescope. The primary goal of EMU is to make a deep (rms ∼ 10 μJy/beam) radio continuum survey of the entire Southern sky at 1.3 GHz, extending as far North as +30° declination, with a resolution of 10 arcsec. EMU is expected to detect and catalogue about 70 million galaxies, including typical star-forming galaxies up to z ∼ 1, powerful starbursts to even greater redshifts, and active galactic nuclei to the edge of the visible Universe. It will undoubtedly discover new classes of object. This paper defines the science goals and parameters of the survey, and describes the development of techniques necessary to maximise the science return from EMU.
The University of Florida (UF) have recently collaborated with Raith Inc. to modify Raith’s ion beam lithography, nanofabrication and engineering (ionLiNE) station that utilizes only Ga ions, into a multi-ion beam system (MionLiNE) by adding the capabilities to use liquid metal alloy sources (LMAIS) to access a variety of ions and an EXB filter for mass separation. The MionLiNE modifications discussed below provide a wide range of spatial and temporal precision that can be used to investigate ion solid interactions under extended boundary conditions, as well as for ion lithography and nanofabrication. Here we demonstrate the ion beam lithographic capabilities of the MionLiNE for fabricating patterned arrays of Au and Si nanocrystals, with nanoscale dimensions, in SiO2 substrates, by direct implantation; and show that the same directwrite/maskless-implantation features can be used for in situ fabrication of nanoelectronic devices. Additionally, the spatial and temporal capabilities of the MionLiNE are used to explore the effects of dose rate on the long-standing surface morphological transformation that occurs in ion bombarded Ge.
Previous research suggests that n-3 PUFA may play a role in bone health. The present analysis aimed to investigate the impact of n-3 PUFA supplementation on bone resorption in adult men and women. Serum samples from 113 mild–moderately depressed individuals (twenty-six males and eighty-seven females, aged 18–67 years) randomised to receive 1·48 g EPA+DHA/d (n 53) or placebo (n 60) for 12 weeks as part of a large recent randomised controlled trial were assayed for n-3 PUFA status and a bone resorption marker, C-terminal cross-linking telopeptide of type 1 collagen (β-CTX). Regression analyses revealed that n-3 PUFA status following supplementation was associated with randomisation (placebo/n-3 PUFA) (B = 3·25, 95 % CI 2·60, 3·91, P < 0·01). However, β-CTX status following supplementation was not associated with randomisation (B = − 0·01, 95 % CI − 0·03, 0·04). Change in β-CTX status was also not associated with change in n-3 PUFA status (B = − 0·002, 95 % CI − 0·01, 0·01). These findings provide no evidence for an association between n-3 PUFA supplementation (1·48 g EPA+DHA/d) for 12 weeks and bone resorption in humans assessed by β-CTX, and suggest that n-3 PUFA supplementation may be unlikely to be of benefit in preventing bone loss.
An assessment of the natural radiation dose to wildlife in England and Wales was made to determine the contribution it may make to the total radiation dose estimated during environmental impact assessments. Significant use was made of systematic datasets for environmental media (stream sediments, stream waters and soils), in particular those produced by the Geochemical Baseline Survey of the Environment (G-BASE) project. This provided extensive, although variable, coverage for different elements and sample types after normalisation of data to account for changes in sampling and analysis over time. Almost complete coverage for K in stream sediments was achieved by merging G-BASE and Wolfson Atlas data. This required normalisation of the Wolfson data to the G-BASE results. Coverage was improved greatly for U and Th in sediments, and K, U and Th in soils, by using the strong relationship between soils and sediments and geology (both solid and superficial) to extrapolate the data. The total U, Th and K data were used to derive activity concentrations of 238U and 232Th series radionuclides and 40K. External dose rates to wildlife were then estimated from derived media concentrations; internal dose rates were estimated from measured activities in biota or activities predicted using recommended concentration ratios.
We present early results from the analysis of HST imaging observations for several pairs of interacting galaxies. We include two cases that were specifically chosen to represent a strong early (young) encounter and a weak late (old) encounter. The goals of the project include a determination of the timing, frequency, strength, and characteristics of the young star clusters formed in these two limiting cases of tidal encounters.
The use of diathermy to achieve haemostasis after tonsillectomy remains controversial. We have reviewed the English language literature, and found no convincing evidence that diathermy is any more likely to cause post-operative haemorrhage than the use of ligatures. The results of a prospective, randomized study of 1036 consecutive tonsillectomies are presented. No significant difference was found in post-operative haemorrhage rates when either diathermy or ligatures were used. Diathermy was found to reduce operating time compared to ligatures. The possibilities for day-case tonsillectomy are discussed.
A low-energy ion beam deposition system has been developed at Oak Ridge National Laboratory and has been applied successfully to the growth of epitaxial films at low temperatures for a number of different elements. The deposition system utilizes the ion source and optics of a commercial ion implantation accelerator. The 35 keV mass- and energy-analyzed ion beam from the accelerator is decelerated in a four-element electrostatic lens assembly to energies between 10 and 500 eV for direct deposition onto a target under UHV conditions. Current densities on the order of 10 A/cm are achieved with good uniformity over a 1.4 cm diameter spot. The completed films are characterized by Rutherford backscattering, ion channeling, cross-section transmission electron microscopy, and x-ray diffraction. The effects of substrate temperature, ion energy, and substrate cleaning have been studied. Epitaxial overlayers which show good minimum yields by ion channeling (3–4%) have been produced at temperatures as low as 375°C for Si on Si(100) and 250°C for Ge on Ge(100) at growth rates that exceed the solid-phase epitaxy rates at these temperatures by more than an order of magnitude.
LiNbO3 is the best substrate for modulators and switches for integrated optics. Efficient low loss waveguides for light in LiNbO3 are formed by introducing Ti-ions into its lattice, thus increasing locally the ordinary and the extraordinary indices of refraction. We are the first to use the very versatile technique of ion-implantation to administer Ti into LiNbO3. This implantation process offers the possibility to introduce significantly more Ti into a well-defined volume than conventional diffusion techniques. During this process first an amorphous non-equilibrium phase is generated, which has to be kept at low temperatures in order to prevent segregation. Subsequent thermal treatment leads to solid phase epitaxy and restores the desired stable crystalline state. We have used this technique to fabricate excellent planar waveguides, channel waveguides and Mach-Zehnder modulators.
Cooper and platinum films were deposited by evaporation and sputtering techniques onto prepared substrates of alumina, sapphire (cut along an a or c axis) and yttria stabilized zirconia. The films are then bombarded with ions of H, He, Ne and Kr at energies within and outside the ion beam mixing regime. Ion beam induced modification in adhesion and its thermal stability were measured by three techniques - a scratch test, a pull test and a peel test. Adhesive energies of these solid-solid systems were determined by contact angle measurements using scanning electron microscopy. The resistance of the films to chemical attack is modified by ion bombardment and will be shown to correlate with adhesion alterations.
Pulsed laser annealing and ion beam mixing have been used as surface modification techniques to enhance the physical properties of polycrystalline α-SiC. Thin Ni overlayers (20 nm - 100 nm) were evaporated onto the SiC surface. The specimens were subsequently irradiated with pulses of a ruby or krypton fluoride (KrF) excimer laser or bombarded with high energy Xe+ or Si+ ions. Both processes are non-equilibrium methods and each has been shown to induce unique microstructural changes at the SiC surface which are not attainable by conventional thermal treatments. Under particular (and optimum) processing conditions, these changes considerably increased the mechanical properties of the SiC; following laser irradiation, the fracture strength of the SiC was increased by as much as 50%, but after ion beam mixing, no strength increase was observed.
High resolution cross-section transmission electron microscopy (X-TEM), scanning electron microscopy (SEM), and Rutherford backscattering techniques were used to characterize the extent of mixing between the Ni and the SiC as a result of the surface modification.
Various models for predicting high fluence ion collection profiles are reviewed. Recent calculations based on the diffusion approximation are described. The solute and defect probability distributions are calculated by a MONTECARLO code, TRIM. The method takes into account the effects of sputtering, including preferential sputtering of one of the components, and lattice dilation. In addition, the effects of radiation enhanced diffusion and radiation induced segregation are also considered. The calculations include the coupling of solute and defect fluxes. The described formalism can account for observed maximum attainable concentrations and distributions in high fluence implantation conditions of practical interest.
Progress in applying rapid thermal annealing for activating implants is surveyed. Advantages to be gained through curtailing substrate semiinsulating loss, enhancing heavy n-type activation, and in reducing the diffusive redistribution of p-type implants are discussed in detail. Consideration is given to encapsulation requirements and the role of stoichiometry in activation. While the emphasis is on GaAs, work on InP and InGaAs has also been included.