The Effect of Local Galaxy Surface Density on Star Formation for HI selected galaxies

We present the result of investigations into two theories to explain the star formation rate-density relationship. For regions of high galaxy density, either there are fewer star forming galaxies, or galaxies capable of forming stars are present but some physical process is suppressing their star formation. We use HI Parkes All Sky Survey's (HIPASS) HI detected galaxies and infrared and radio fluxes to investigate star formation rates and efficiencies with respect to local surface density. For nearby (vel<10000 km\s) HI galaxies we find a strong correlation between HI mass and star formation rate. The number of HI galaxies decreases with increasing local surface density. For HI galaxies (1000<vel<6000 km\s) there is no significant change in the star formation rate or the efficiency of star formation with respect to local surface density. We conclude the SFR-density relation is due to a decrease in the number of HI star forming galaxies in regions of high galaxy density and not to the suppression of star formation.Comment: 17 pages, 16 figures, Accepted for publication by MNRAS 2 August 200

The Large Peculiar Velocity of the cD Galaxy in Abell 3653

We present a catalogue of galaxies in Abell 3653 from observations made with the 2dF spectrograph at the Anglo-Australian Telescope. Of the 391 objects observed, we find 111 are bone-fide members of Abell 3653. We show that the cluster has a velocity of cz = 32214 +/- 83 km/s (z=0.10738 +/- 0.00027), with a velocity dispersion typical of rich, massive clusters of sigma_{cz} = 880^{+66}_{-54}. We find that the cD galaxy has a peculiar velocity of 683 +/- 96 km/s in the cluster restframe - some 7sigma away from the mean cluster velocity, making it one of the largest and most significant peculiar velocities found for a cD galaxy to date. We investigate the cluster for signs of substructure, but do not find any significant groupings on any length scale. We consider the implications of our findings on cD formation theories.Comment: 16 pages, including 7 figures and a long table. Accepted for publication in MNRA

Participatory Approaches to Program Development and Engaging Youth in Research: The Case of an Inter-Generational Urban Community Gardening Program

We applied participatory models of program development and research in an inter-generational program whose goal was for youth to document ethnic gardening practices in urban community gardens. Outcomes for educators included professional development and the opportunity to expand their programs to urban audiences, whereas youth learned about gardening, developed positive relationships with elders, and enhanced their academic skills. Developing relationships with youth was an important outcome for gardeners. Through examining what motivates various participants and how they benefit, we may be able to enhance our understanding of how best to work with educators to design a youth participatory research program

Heat: An Inquiry-based Physics Laboratory for Life Sciences Students

We have developed an inquiry-based first-year undergraduate experiment to investigate heat transfer. Students consider the real-world problem of how the temperature inside a building is influenced by various factors. Students develop their understanding of heat transfer through scaffolding experiments, and then construct a simple model house, and monitor its internal temperature when exposed to ambient conditions over a 24-hour period. In a following session, based on their acquired knowledge, teams design and test a model building according to their own chosen goal (constant-temperature house, greenhouse, etc.). As an extension, students also examine the insulating characteristics of animals. Class observation, analysis of student responses and survey data show that the activity successfully engages students, better motivating them to understand the physics involved. They have to deal with problems that arise during the experiments and discuss solutions with their group members. They encounter other interesting questions as they try to achieve their goal, and learn more science in the process. The aspects of this activity that work particularly well are the realism of the scenario, a degree of student ownership of experiments, and controlled variation in what students do through the design choices possible

Non-cognitive Child Outcomes and Universal High Quality Child Care

Abstract: Exploiting a rich panel data child survey merged with administrative records along with a pseudo-experiment generating variation in the take-up of pre-school across municipalities, we provide evidence of the effects on non-cognitive child outcomes of participating in large scale publicly provided universal pre-school programs and family day care vis-à-vis home care. We find that, compared to home care, being enrolled in pre-school at age three does not lead to significant differences in child outcomes at age seven no matter the gender or mother&apos;s level of education. Family day care, on the other hand, seems to significantly deteriorate outcomes for boys whose mothers have a lower level of education. Finally, increasing hours in family day care Research. We are thankful to Mette Lausten for data assistance and to Niels Glavind from Bureau 2000 for supplying crucial information on child care guarantees. We would like to than

Choirs, HI galaxy groups: Catalogue and detection of star-forming dwarf group members

Hα observations centred on galaxies selected from the HI Parkes All-Sky Survey (HIPASS)typically show one and sometimes two star-forming galaxies within the ~15 arcmin beam of the Parkes 64 m HI detections. In our Survey for Ionization in Neutral Gas Ga

Reasons for not commencing direct-acting antiviral treatment despite unrestricted access for individuals with HIV and hepatitis C virus: a multinational, prospective cohort study.

BACKGROUND Individuals with HIV and hepatitis C virus (HCV) who remain untreated with direct-acting antivirals can contribute to HCV transmission and HCV-related mortality. We aimed to compare rates of uptake of direct-acting antivirals following unrestricted access to this treatment in high-income countries and examine factors associated with remaining untreated. METHODS This multinational, prospective cohort study used data from the International Collaboration on Hepatitis C Elimination in HIV Cohorts (InCHEHC). We analysed data from nine observational cohorts participating in the InCHEHC, including data from six high-income countries (Australia, Canada, France, the Netherlands, Spain, and Switzerland). We included individuals aged 18 years and older, with HIV and HCV (ie, HCV-RNA positive without evidence of spontaneous clearance) during unrestricted access to interferon-free direct-acting antiviral treatment in each country. We calculated the cumulative proportion of participants who remained untreated with direct-acting antivirals, with follow-up starting after the date of unrestricted access or cohort inclusion, whichever occurred most recently. Factors associated with the commencement rate of direct-acting antiviral treatment were assessed using competing-risks regression with the Fine-Gray method. FINDINGS The date of unrestricted access to direct-acting antiviral treatment for people with HIV ranged from Nov 1, 2014, in France to Nov 1, 2017, in Switzerland. We included 4552 individuals with HIV-HCV, mainly men who have sex with men (MSM; n=2156 [47%]) and people who inject or have injected drugs (n=1453 [32%]). 1365 (30%) of 4552 participants remained untreated with direct-acting antivirals. For individuals treated with direct-acting antivirals, median time from start of follow-up to treatment was 5 months (IQR 2-12). For individuals who were not treated with direct-acting antivirals, median follow-up was 22 months (8-30). Being linked to care in Australia, France, or the Netherlands, on antiretroviral therapy, having undetectable HIV RNA, and shorter duration since first positive HCV test were independently associated with higher commencement rate of direct-acting antiviral treatment. Compared with MSM, male heterosexuals and females with unknown or other routes of HIV transmission (ie, neither injection drug use nor heterosexual transmission) had lower rates of commencement. INTERPRETATION Despite unrestricted access, almost a third of individuals with HIV-HCV remained untreated with direct-acting antivirals during follow-up, with variation in commencement rate of HCV treatment between countries and key populations. Increased efforts are required to reach the remaining individuals with HIV who are HCV-viraemic to achieve HIV-HCV micro-elimination. FUNDING None

Galaxy Groups: Proceedings from a Swinburne University Workshop

We present the proceedings from a 2-day workshop held at Swinburne University on the 24th-25th of May 2005. The workshop participants highlighted current Australian research on both theoretical and observational aspects of galaxy groups. These proceedings include short 1-page summaries of a number of the talks presented at the workshop. The talks presented ranged from reconciling N-body simulations with observations, to the HI content of galaxies in groups and the existence of ``dark galaxies''. The formation and existence of ultra-compact dwarfs in groups, and a new supergroup in Eridanus were also discussed.Comment: to be published in PAS

The Neutral Hydrogen Properties of Galaxies in Gas-rich Groups

We present an analysis of the integrated neutral hydrogen (Hi) properties for 27 galaxies within nine low mass, gas-rich, late-type dominated groups which we denote \Choirs". We find that majority of the central Choir galaxies have average Hi content: they have a normal gas-mass fraction with respect to isolated galaxies of the same stellar mass. In contrast, we find more satellite galaxies with a lower gas-mass fraction than isolated galaxies of the same stellar mass. A likely reason for the lower gas content in these galaxies is tidal stripping. Both the specific star formation rate and the star formation efficiency of the central group galaxies are similar to galaxies in isolation. The Choir satellite galaxies have similar specific star formation rate as galaxies in isolation, therefore satellites that exhibit a higher star formation efficiency simply owe it to their lower gas-mass fractions. We find that the most Hi massive galaxies have the largest Hi discs and fall neatly onto the Hi size-mass relation, while outliers are galaxies that are experiencing interactions. We find that high specific angular momentum could be a reason for galaxies to retain the large fraction of Hi gas in their discs. This shows that for the Choir groups with no evidence of interactions, as well as those with traces of minor mergers, the internal galaxy properties dominate over the effects of residing in a group. The probed galaxy properties strengthen evidence that the Choir groups represent the early stages of group assembly

The Northern HIPASS catalogue - Data presentation, completeness and reliability measures

The Northern HIPASS catalogue (NHICAT) is the northern extension of the HIPASS catalogue, HICAT (Meyer et al. 2004). This extension adds the sky area between the declination range of +2 deg < dec. < +25.5 deg to HICAT's declination range of -90 deg < dec. < +2 deg. HIPASS is a blind HI survey using the Parkes Radio Telescope covering 71% of the sky (including this northern extension) and a heliocentric velocity range of -1,280 km/s to 12,700 km/s . The entire Virgo Cluster region has been observed in the Northern HIPASS. The galaxy catalogue, NHICAT, contains 1002 sources with v_hel > 300 km/s . Sources with -300 km/s < v_hel < 300 km/s were excluded to avoid contamination by Galactic emission. In total, the entire HIPASS survey has found 5317 galaxies identified purely by their HI content. The full galaxy catalogue is publicly-available at .Comment: 12 pages, accepted for publication by MNRA