Abundances from solar flare line spectroscopy

Updating and improvement of computer codes used in the abundance analyses of solar-flare gamma-ray data are described. These modifications are itemized in detail. The abundance analysis technique was then applied to data obtained by the Gamma-Ray Spectrometer of the Solar Maximum Mission spacecraft for the 27 April 1981 solar flare to set constraints on the interacting-particle angular distribution. The results are presented. Research in several other areas was also performed and they are discussed

GRO source candidates: (A) Nearby modest-size molecular clouds; (B) Pulsar with Wolf-Rayet companion that has lost its H-envelope

Within 100 pc of the sun there are over a hundred cirrus clouds with masses of approx. 60 solar mass and dense molecular clouds with masses of approx. 4 solar mass. If the local interstellar density of cosmic rays is also present in these clouds, the flux of neutral pion from the decay of gamma rays from the core of a cloud at a distance of 20 pc is approx. 13 x 10(exp -8) photons/sq cm/s. The flux from the more extensive cirrus cloud is approx 4 x 10(exp -7) photons/sq cm/s. A relativistic beam of particles generated by a compact stellar object and incident upon a large, close companion can be a strong gamma ray line source if more of the beam energy is used in interactions with C and O and heavier nuclei and less with H and He. This would be the case if the companion has lost its hydrogen envelope and nucleosynthesized much of its He into C, O, and Ne. Such objects are Wolf-Rayet stars and it is believed that some Wolf-Rayet stars do, in fact, have compact companions. For a beam of protons of 10(exp 37) erg/s, the flux at 1 kpc of the 4.4 MeV C-12 line could be as high as 5 x 10(exp -6) photons/sq cm/s. The fluxes of the deexcitation lines from the spallation products of O-16 are also presented

Yggdrasil and the Stave Church

In this excerpt from his book, Tree of Salvation, Murphy explores how those who introduced Christianity to Scandinavia deliberately adapted and “translated” Norse religious motifs and practices in two parallel ways—through literary works, especially as seen in the Heliand, but also through church art and architecture. In this illustrated essay, we can see how beliefs about Yggdrasil and Ragnarok are incorporated and transformed in the design and ornamentation of the unusual stave churches of Norway. Scholar GOH speech, Mythcon 2012

Brain Drain and Regain: The Migration Behaviour of South African Medical Professionals (Migration Policy Series No. 65)

Since the end of apartheid, South Africa has experienced a significant outflow of health professionals. The out-migration of health professionals from the country is part of a broader global trend of health professional migration from the Global South to the Global North. In the health sector, this “brain drain” has led to a significant decline in the quality of care in affected countries. The costs of health professional migration for countries of origin are usually measured in terms of lost investment in training and the gaps in medical care left by their departure. One recent study, for example, estimated that the cost to South Africa in lost investment in training from the emigration of health physicians to Australia, Canada, the United States and the United Kingdom amounts to USD1.4 billion. Previous studies have predicted that medical migration from South Africa is unlikely to subside in the short and medium term as health professionals and trainees exhibit very high emigration potential. This report provides an updated (2013) picture of the state of mind of South African health professionals. It also allows an assessment of whether professional attitudes and perceptions have changed between 2007 and 2013 including (a) whether levels of satisfaction with work and life in South Africa have improved or worsened; (b) whether emigration potential has declined or intensified amongst health professionals and (c) whether the “brain drain” from South Africa is likely to continue. These questions are of particular relevance given various changes in the health sector since 2007. Return migration has been advocated internationally as an antidote to the brain drain and an important downstream benefit for countries of origin in the South. This report therefore provides important new information about the implications of health professional return migration to South Africa. Another strategy adopted by some countries is to use immigration policy as a means of dealing with health professional shortages. South Africa is a destination country for health professionals from some countries although, with the exception of official schemes to temporarily import Cuban and Tunisian doctors, this is not official policy. Significantly, the medical professions have only just appeared on the government scarceskills lists that have been published for nearly a decade. This survey provided an opportunity to profile a sub-group of non-South African doctors to assess whether they are more inclined to remain in the country than their South African counterparts. The current survey was developed in collaboration with the Institute of Population Health at the University of Ottawa as part of a CIHR-funded global project on health professional migration from India, Jamaica, the Philippines and South Africa. The questionnaire was hosted on the MEDpages website and potential respondents were invited by email to complete the survey. A total of 1,383 completed questionnaires were received from physicians, dentists and pharmacists – a response rate of 7%

No. 65: Brain Drain and Regain: The Migration Behaviour of South African Medical Professionals

Since the end of apartheid, South Africa has experienced a significant outflow of health professionals. The out-migration of health professionals from the country is part of a broader global trend of health professional migration from the Global South to the Global North. In the health sector, this “brain drain” has led to a significant decline in the quality of care in affected countries. The costs of health professional migration for countries of origin are usually measured in terms of lost investment in training and the gaps in medical care left by their departure. One recent study, for example, estimated that the cost to South Africa in lost investment in training from the emigration of health physicians to Australia, Canada, the United States and the United Kingdom amounts to USD1.4 billion. Previous studies have predicted that medical migration from South Africa is unlikely to subside in the short and medium term as health professionals and trainees exhibit very high emigration potential. This report provides an updated (2013) picture of the state of mind of South African health professionals. It also allows an assessment of whether professional attitudes and perceptions have changed between 2007 and 2013 including (a) whether levels of satisfaction with work and life in South Africa have improved or worsened; (b) whether emigration potential has declined or intensified amongst health professionals and (c) whether the “brain drain” from South Africa is likely to continue. These questions are of particular relevance given various changes in the health sector since 2007. Return migration has been advocated internationally as an antidote to the brain drain and an important downstream benefit for countries of origin in the South. This report therefore provides important new information about the implications of health professional return migration to South Africa. Another strategy adopted by some countries is to use immigration policy as a means of dealing with health professional shortages. South Africa is a destination country for health professionals from some countries although, with the exception of official schemes to temporarily import Cuban and Tunisian doctors, this is not official policy. Significantly, the medical professions have only just appeared on the government scarceskills lists that have been published for nearly a decade. This survey provided an opportunity to profile a sub-group of non-South African doctors to assess whether they are more inclined to remain in the country than their South African counterparts. The current survey was developed in collaboration with the Institute of Population Health at the University of Ottawa as part of a CIHR-funded global project on health professional migration from India, Jamaica, the Philippines and South Africa. The questionnaire was hosted on the MEDpages website and potential respondents were invited by email to complete the survey. A total of 1,383 completed questionnaires were received from physicians, dentists and pharmacists – a response rate of 7%

The Li-7 and Be-7 deexcitation lines: Probes for accelerated particle transport models in solar flares

The photon energy spectrum of a spectral feature composed of the 429 and 478 keV gamma-ray lines from Li-7 and Be-7 (produced by interactions of flare-accelerated alpha particles with ambient He in the solar atmosphere) depends on the angular distribution of the interacting accelerated particles. This spectrum is calculated for limb and disc-centered flares using a loop model for the transport of the ions. In this model, the flux tube magnetic field is constant in the corona and converges in the chromosphere to the photosphere. Magnetic mirroring and MHD pitch-angle scattering are both taken into account. Comparison of these results with data from other experiments is presented

Ultra- and Hyper-compact HII regions at 20 GHz

We present radio and infrared observations of 4 hyper-compact HII regions and 4 ultra-compact HII regions in the southern Galactic plane. These objects were selected from a blind survey for UCHII regions using data from two new radio surveys of the southern sky; the Australia Telescope 20 GHz survey (AT20G) and the 2nd epoch Molonglo Galactic Plane Survey (MGPS-2) at 843 MHz. To our knowledge, this is the first blind radio survey for hyper- and ultra-compact HII regions. We have followed up these sources with the Australia Telescope Compact Array to obtain H70-alpha recombination line measurements, higher resolution images at 20 GHz and flux density measurements at 30, 40 and 95 GHz. From this we have determined sizes and recombination line temperatures as well as modeling the spectral energy distributions to determine emission measures. We have classified the sources as hyper-compact or ultra-compact on the basis of their physical parameters, in comparison with benchmark parameters from the literature. Several of these bright, compact sources are potential calibrators for the Low Frequency Instrument (30-70 GHz) and the 100-GHz channel of the High Frequency Instrument of the Planck satellite mission. They may also be useful as calibrators for the Australia Telescope Compact Array, which lacks good non-variable primary flux calibrators at higher frequencies and in the Galactic plane region. Our spectral energy distributions allow the flux densities within the Planck bands to be determined, although our high frequency observations show that several sources have excess emission at 95 GHz (3 mm) that can not be explained by current models.Comment: 13 pages, 7 figures, accepted for publication in MNRA

Reproduction and Growth of Black Drum, Pogonias cromis, in Northeast Florida

Age, growth, and reproduction of black drum, Pogonias cromis, in northeast Florida were investigated between December 1983 and April 1985. Male black drum began maturing at 450-499 mm total length (TL), with 50% of them reaching maturity at about 590 mm (age 4 or 5). Vitellogenesis began at 450-550 mm TL, with 50% of the females reaching maturity at 650-699 mm (age 5 or 6). Spawning occurred during January - April. Thin sections of otoliths displayed distinct opaque bands; the first three or four of these bands were verified by marginal increment analysis as being annuli deposited during March - May. The growth rate was about 100 mm yr-1 for ages 1·3 and gradually slowed to 10·30 mm yr-1 for ages 15-20. Male and female growth rates did not differ significantly, at least through age 4. Length at age was predicted well by the equation mm TL = 1172 mm (1 - exp (- 0.12 (AGE+ 1.3))). The apparent maximum age of black drum is about 50-60 years

Directionality of Solar Flare Accelerated Protons and Alpha Particles from Gamma-Ray Line Measurements

The energies and widths of gamma-ray lines emitted by ambient nuclei excited by flare-accelerated protons and alpha particles provide information on the ions directionality and spectra, and on the characteristics of the interaction region. We have measured the energies and widths of strong lines from de-excitations of 12C, 16O, and 20Ne in solar flares as a function of heliocentric angle. The line energies from all three nuclei exhibit ~1% redshifts for flares at small heliocentric angles, but are not shifted near the limb. The lines have widths of ~3% FWHM. We compare the 12C line measurements for flares at five different heliocentric angles with calculations for different interacting-particle distributions. A downward isotropic distribution (or one with a small upward component) provides a good fit to the line measurements. An angular distribution derived for particles that undergo significant pitch angle scattering by MHD turbulence in coronal magnetic loops provides comparably good fits