P.E. Strzelecki, Australian explorer, 1797-1873.

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The Application of Mossbauer Spectroscopy to the Study of Corrosion

The Mossbauer spectroscopic methods that have been used for studying corrosion phenomena include transmission, emission and reflection (scatterimg) techniques. Each of these techniques provides unique capabilities for studying a wide range of applied and fundamental corrosion problems. The various Mossbauer spectroscopic techniques are described and compared, and applications of each method to corrosion studies are reviewed

Preparation and characterization of Bi26–2xMn2xMo10O69-d and Bi26.4Mn0.6Mo10–2yMe2yO69-d(Me = V, Fe) solid solutions

Received: 06.06.2017; accepted: 23.06.2017; published: 14.07.2017.Single phase samples of bismuth molybdate, Bi26Mo10O69, doped with Mn on the bismuth sublattice and V, Fe on the molybdenum sublattice were found to crystallize in the triclinic Bi26Mo10O69 structure at low doping levels and in the monoclinic Bi26Mo10O69 structure - at higher dopant concentration. The assumption that all Mn ions have an oxidation state of +2 was confirmed by means of magnetic measurement results analysis using Curie-Weiss law. Conductivity was investigated using impedance spectroscopy. The conductivity of Bi26.4Mn0.6Mo9.6Fe0.4O69-d was 1.2*10-2 S*cm-1 at 973 K and 2.2*10-4 S*cm-1 at 623 K, and the conductivity of Bi26.4Mn0.6Mo9.2V0.8O69-d was 2.2*10-3 S*cm-1 at 973 K and 2.2*10-5 S*cm-1 at 623 K

Space VLBI Observations of 3C371

We present the first space VLBI observations of 3C~371, carried out at a frequency of 4.8 GHz. The combination of the high resolution provided by the orbiting antenna Highly Advanced Laboratory for Communications and Astronomy (HALCA) and the high sensitivity of the VLBA allows imaging of the jet of 3C~371 with an angular resolution of approximately 0.26 mas, which for this relatively nearby source corresponds to $\sim$ 0.4 h$^{-1}$ pc. Comparison between two epochs separated by 66 days reveals no apparent motions in the inner 7 mas jet structure above an upper limit of $\sim 1.4 h^{-1}$ c. This value, the absence of detectable counterjet emission from the presumably symmetric jet, plus the presence of extended double-lobe structure, are consistent with the knots in the jet being stationary features such as standing shocks. The jet intensity declines with the angular distance from the core as $\phi^{-1.68}$. This is more gradual than that derived for 3C~120, $\phi^{-1.86}$, for which there is evidence for strong intereactions between the jet and ambient medium. This suggests that in 3C~371 there is a greater level of {\it in situ} acceleration of electrons and amplification of magnetic field. We interpret sharp bends in the jet at sites of off-center knots as further evidence for the interaction between the jet and external medium, which may also be responsible for the generation of standing recollimation shocks. These recollimation shocks may be responsible for the presumably stationary components. The radio properties of 3C~371 are intermediate between those of other radio galaxies with bright cores and those of BL Lacertae objects.Comment: 5 pages, 4 figures. Accepted for publication in Ap

Family centred approach for HIV services: Pilot study in South Africa

In 2003, UNICEF estimated that nearly 250,000 children were infected with HIV in South Africa. While scale-up of prevention of mother-to-child transmission (PMTCT) programs has improved testing and care for perinatally infected infants, uptake of these services remains low in much of sub-Saharan Africa and few HIV infected children are diagnosed and receive services through PMTCT programs. With support from USAID/PEPFAR, the Horizons Program adapted a family-centered model for children and families in need of broader-reaching HIV diagnostic services in South Africa. The Family Centered Approach (FCA) pilot intervention was designed to expand access to HIV testing for family members with children ages 0–14 years in their care. This approach gives health-care providers a method for encouraging HIV-positive individuals to refer family members for HIV testing, with the aim of identifying HIV-positive children ages 0–14 years who may have been missed through PMTCT early infant diagnosis programs. This research summary describes the FCA pilot intervention

Monte Carlo simulations of ion-enhanced island coarsening

Monte Carlo simulations of growth and ion bombardment have been performed to explore the atomistic processes that occur during ion-assisted growth. The primary elements of the simulation are (1) creation of surface defects (vacancies and adatoms) by ion bombardment and deposition, (2) thermally activated motion of surface defects and (3) recombination of surface vacancies and adatoms. The authors find that a balance of ion bombardment and deposition (where the creation rate of adatom defects is equal to that of surface vacancies) leads to larger islands and more rapid island coarsening than thermal coarsening with no flux of defects. The presence of the defect flux enhances the breakup of clusters, leading to a broad distribution of island sizes. In comparison, the thermal coarsening leads to a more uniform distribution of islands sizes that increases in size much more slowly. Histograms of the evolution of the island size distribution provide a quantitative measure of the ion-induced increase in the rate of coarsening

Looking back, moving forward: Access to antiretroviral therapy for HIV infected adults and children in developing countries: Horizons Studies, 2002 to 2008

In 1997, the Population Council initiated the Horizons Program—a decade-long USAID-funded collaboration with the International Center for Research on Women, the International HIV/AIDS Alliance, PATH, Tulane University, Family Health International, and Johns Hopkins University—designing, implementing, evaluating, and expanding innovative strategies for HIV prevention and care. Horizons developed and tested ways to optimize HIV prevention, care, and treatment programs; worked to reduce stigma and improve gender-biased behaviors; and greatly expanded knowledge about the best ways to support, protect, and treat children affected by HIV and AIDS. In all its projects, Horizons strengthened the capacity of local institutions by providing support and training to colleagues. This synthesis paper presents lessons learned and best practices on one of the key topics that Horizons investigated: access to antiretroviral therapy