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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.
Ultra-luminous infrared galaxies (ULIRGs; L > 1012 L⊙) are quite rare in the local universe, but seem to dominate the co-moving energy density at z > 2. Many are optically-faint, dust-obscured galaxies that have been identified only relatively recently by the detection of their thermal dust emission redshifted into the sub-mm wavelengths. These submm galaxies (SMGs) have been shown to be a massive objects (M* ~ 1011 M⊙) undergoing intense star-formation(SFRs ~ 102 − 103 M⊙ yr−1) and the likely progenitors of massive ellipticals today. However, the AGN contribution to the far-IR luminosity had for years remained a caveat to these results. We used the Spitzer Infrared Spectrograph (IRS) to investigate the energetics of 24 radio-identified and spectroscopically-confirmed SMGs in the redshift range of 0.6 < z < 3.2. We find emission from Polycyclic Aromatic Hydrocarbons (PAHs) – which are associated with intense star-formation activity – in >80% of our sample and find that the median mid-IR spectrum is well described by a starburst component with an additional power-law continuum representing < 32% AGN contribution to the far-IR luminosity. We also find evidence for a more extended distribution of warm dust in SMGs compared to the more compact nuclear bursts in local ULIRGs and starbursts, suggesting that SMGs are not simple high-redshift analogs of local ULIRGs or nuclear starbursts, but have star formation which resembles that seen in less-extreme star-forming environments at z ~ 0.
In this paper we report on an investigation of statistical weak gravitational lensing of cosmologically distant faint galaxies by foreground galaxies. The signal we seek is a distortion of the images of faint galaxies resulting in a weakly preferred tangential alignment of faint galaxies around brighter galaxies. That is, if the faint galaxies have been gravitationally lensed by the brighter systems, the major axes of their images will tend to lie perpendicular to the radius vectors joining the centroids of the faint and bright galaxies (Fig. 1). Modeling a lens galaxy as a singular isothermal sphere with circular velocity Vc, an ellipticity of ∼ 2πVc2 /c2θ is induced in the image of a source galaxy at an angular separation θ from the lens. This is of order a few percent for faint–bright galaxy pairs with separations θ ∼ 30″ where the lens is a typical bright spiral. Over 1000 pairs must be measured in order to detect such a signal in the presence of the noise associated with the intrinsic galaxy shapes. Given a sufficiently large number of pairs, it may be possible to use the variation of the induced ellipticity with θ to study the angular extent of the halos of the lens galaxies.
Cats were repeatedly inoculated with infective larvae of Brugia pahangi. On parasitological grounds they could be divided into 5 groups. Group I – most cats (some 70%) became microfilaraemic (mf+) and retained high levels of microfilariae (mf) in their blood for over 2 years. In some Group I cats mf counts stabilized at high levels whilst in others mf counts continued to increase. Large numbers of fecund adult worms were recovered from their lymphatics. Adult counts were not made on the cats in the current experiments but over 100 adults have been recovered from ‘super-susceptible’ cats. Large amounts of B. pahangi adult antigen were consistently present in the serum of all Group I cats. About 30% of cats became amicrofilaraemic (mf–). In these cats the peak mf levels were seldom above 10000 mf/ml. Group II – these cats had less than 10 000 mf/ml and low antigen levels. After more than 1 year of being repeatedly infected B. pahangi adult antigen slowly declined and eventually could no longer be detected in their serum and the number of mf declined very slowly after the fall in antigen levels. This shows that in Group II cats the adult worms die and as the cats are resistant to the development of the continuing weekly inoculation of L3 no new adults can develop. Group III – these cats became mf – during the first year of infection but remained B. pahangi antigen-positive for many weeks after this and, at autopsy, had living adults in their lymphatics. Group IV – in these cats there was a sudden decline in the number of mf, usually in the first year and after they have received a relatively small number of re-infections. Circulating adult B. pahangi antigen disappeared from the serum within a short time of the loss of mf and at autopsy no adult female worms were found. Group V – these cats do not become mf+ when infected. These groups are compared to the parasitological groups seen in areas endemic for infection with Wuchereria bancrofti.
Laser induced fluorescence of CF2 has been observed in plasmas of CF4 and its mixtures with O2 and H2. Surface removal rates of the radical in pure CF4 were measured by observing the decay of the radical when the plasma is switched off. The reduction in CF2 concentration, and the increase in F atom concentrations (the latter measured by optical emission spectroscopy) on the addition of O2 is reproduced by a model of the plasma in which gas phase chemical reactions play a dominant role. The increase in CF2 concentration on the addition of H2 to a CF4 plasma is shown to be due to a reduction in the surface removal rate.
Optical Emission Spectroscopy (OES) with argon actinometry has been used to study the influence of machine parameters on the composition of a BCl3 RF plasma discharge in the absence and presence of aluminium. Two steady state models are proposed to account for the appearance of the various species seen, and to explain their relative abundances in response to changes in power and pressure. The validity of the actinometric technique for measuring relative changes in ground state concentrations is discussed also.
Viral erythrocytic necrosis (VEN) in fish is prevalent in a wide variety offish species. It has been detected in both wild and captive fish populations. The infection prevalence in wild populations of some fish species is correlated inversely with the age of the fish. VEN is characterised by cytoplasmic inclusions in circulating erythrocytes of infected fish; nuclear necrosis of erythrocytes may also be evident by light microscopy. The stage and degree of infection affect the type of cytology seen in VEN infections of different fish species. By electron microscopy, infected erythrocytes show spherical virions within the cytoplasm and the virion size is characteristic of the host erythrocytes infected. To date, knowledge of VEN viruses in fish is restricted to virus morphology and propagation in vivo, although preliminary studies have indicated the type of blood parameters which VEN can affect. No such virus has been fully isolated and characterised and all of Koch's postulates have not been fulfilled.
The process whereby neurotic symptoms are generated, and the degree to which they are linked to pre-existent personality traits, is still a matter of debate in psychiatric and psychological literature. On the basis of the medical model, symptoms may be thought of as intruding unaccountably (from the subjective point of view) into the individual's experience as part of a disease process. This standpoint, where it exists, must be accepted as an article of faith, since no convincing demonstration of how a phobia or an obsession, for example, can be accounted for in this way has yet been put forward. However, cogent arguments have been advanced (e.g. Foulds 1965) for regarding symptoms as distinct from personality traits; in part such arguments have been occasioned by the confusion in psychiatric diagnosis between concepts such as ‘hysteria’ and ‘hysterical personality’.
One of the most attractive features of the Repertory Grid Technique from the clinician's point of view is that it provides a quantifiable test of hypotheses concerning data which are not readily measurable by more traditional standardized instruments (such as questionnaires). An example of such a situation as this would be where the psychologist wishes to measure change in a person's construing of his world before and after psychotherapy. This immediately involves, however, questions concerning the “reliability” and “validity” of the particular grid or grids used. How do we know whether reasonably stable psychological processes within the individual are reflected in equally stable mathematical relationships between constructs, and how do we know that we have chosen, or elicited, those constructs which really are most psychologically meaningful to the subject, or indeed psychologically meaningful at all ?
A number of studies have shown with psychological testing that the form a particular response takes will depend on the personal relevance to the subject of the stimulus, and that the more personally relevant the stimulus the less the effects of other response determinants. For example, Dahlstrom (1962) has listed six “contextual” and five “mediating” variables which he feels account for responses to such test items as those composing the M.M.P.I. These variables include the experimental setting, the examiner and the specific test items (contextual variables), and the veridical facts, personality styles, test instructions (mediating variables). Similar arguments have been advanced with regard to projective testing by Hutt (1951, 1954) and Wertheimer (1957), among others. Caine (1967) has shown that response suppression operates in a sentence building test only when the test material is of limited personal significance to the subject, and that the consistency of response between different testing levels along the overt/covert dimension pertains only when the stimulus material is of psycho-pathological significance. With the T.A.T., Smail (1966) has argued that if meaningful results are to be obtained responses must be interpreted in the light of the patient's particular situation much more than is the general practice, and that responses which are clinically typical of a given diagnostic group may only appear where the stimulus card accurately reflects the situation in which the patient finds himself.
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