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Mechanistic home range analysis (MHRA) is a highly effective tool for understanding spacing patterns of animal populations. It has hitherto focused on populations where animals defend their territories by communicating indirectly, e.g. via scent marks. However, many animal populations defend their territories using direct interactions, such as ritualized aggression. To enable application of MHRA to such populations, we construct a model of direct territorial interactions, using linear stability analysis and energy methods to understand when territorial patterns may form. We show that spatial memory of past interactions is vital for pattern formation, as is memory of ‘safe’ places, where the animal has visited but not suffered recent territorial encounters. Additionally, the spatial range over which animals make decisions to move is key to understanding the size and shape of their resulting territories. Analysis using energy methods, on a simplified version of our system, shows that stability in the nonlinear system corresponds well to predictions of linear analysis. We also uncover a hysteresis in the process of territory formation, so that formation may depend crucially on initial space-use. Our analysis, in one dimension and two dimensions, provides mathematical groundwork required for extending MHRA to situations where territories are defended by direct encounters.

"An international conference titled 'Transforming Health Care in Remote Communities' was held at the Chateau Lacombe Hotel in Edmonton, Canada, April 28–30, 2016. The event was organized by the University of Alberta’s School of Public Health, in partnership with the Institute for Circumpolar Health Research in Yellowknife, Northwest Territories, and the Qaujigiartiit Health Research Centre in Iqaluit, Nunavut. There were 150 registrants from 7 countries: Canada (7 provinces and 3 territories), United States, Denmark, Iceland, Norway, Sweden, and Australia. They included representatives of academic institutions, health care agencies, government ministries, community organizations, and private industry. The Conference focused on developing solutions to address health care in remote regions. It enabled new networks to be established and existing ones consolidated." (as cited in abstract)

We present new results on the shock around the south-west radio lobe of Centaurus A using data from the Chandra Very Large Programme observations (740 ks total observing time). The X-ray spectrum of the emission around the outer south-western edge of the lobe is well described by a single power-law model with Galactic absorption – thermal models are strongly disfavoured, except in the region closest to the nucleus. We conclude that a significant fraction of the X-ray emission around the south-west part of the lobe is synchrotron, not thermal. We infer that in the region where the shock is strongest and the ambient gas density lowest, the inflation of the lobe is accelerating particles to X-ray synchrotron emitting energies, similar to supernova remnants such as SN1006. This interpretation resolves a problem of our earlier, purely thermal, interpretation for this emission, namely that the density compression across the shock was required to be much larger than the theoretically expected factor of 4. We describe a self-consistent model for the lobe dynamics and shock properties using the shell of thermal emission to the north of the lobe to estimate the lobe pressure. Based on this model, we estimate that the lobe is expanding to the south-west with a velocity of ∼2600 km s−1 , roughly Mach 8 relative to the ambient medium. We discuss the spatial variation of spectral index across the shock region, concluding that our observations constrain γmax for the accelerated particles to be ∼108 at the strongest part of the shock, consistent with expectations from diffusive shock acceleration theory. Finally, we consider the implications of these results for the production of ultra-high energy cosmic rays (UHECRs) and TeV emission from Centaurus A, concluding that the shock front region is unlikely to be a significant source of UHECRs, but that TeV emission from this region is expected at levels comparable to current limits at TeV energies, for plausible assumed magnetic field strengths. ‘The definitive version is available at www3.interscience.wiley.com '. Copyright Blackwell Publishing / Royal Astronomical Society. DOI: 10.1111/j.1365-2966.2009.14715.x Peer reviewed

Aims. Based on the archival data from the Chandra observations of nearby galaxies, we study different sub populations of low-mass X-ray binaries (LMXBs) - dynamically formed systems in globular clusters (GCs) and in the nucleus of M 31 and (presumably primordial) X-ray binaries in the fields of galaxies. Our aim is to produce accurate luminosity distributions of X-ray binaries in different environments, suitable for quantitative comparison with each other and with the output of population synthesis calculations. Methods. Our sample includes seven nearby galaxies (M 31, Maffei 1, Centaurus A, M 81, NGC 3379, NGC 4697, and NGC 4278) and the Milky Way, which together provide relatively uniform coverage down to the luminosity limit of 10(35) erg s(-1). In total we have detected 185 LMXBs associated with GCs, 35 X-ray sources in the nucleus of M 31, and 998 field sources of which similar to 365 are expected to be background AGN. We combine these data, taking special care to accurately account for X-ray and optical incompleteness corrections and the removal of the contamination from the cosmic X-ray background sources, to produce luminosity distributions of X-ray binaries in different environments to far greater accuracy than has been obtained previously. Results. We found that luminosity distributions of GC and field LMXBs differ throughout the entire luminosity range, the fraction of faint (log(L-X) < 37) sources among the former being similar to 4 times less than in the field population. The X-ray luminosity function (XLF) of sources in the nucleus of M 31 is similar to that of GC sources at the faint end but differs at the bright end, with the M 31 nucleus hosting significantly fewer bright sources. We discuss the possible origin and potential implications of these results. Original article can be found at: http://www.aanda.org/ Copyright The European Southern Observatory Peer reviewed

Background: Public health researchers are increasingly encouraged to establish international collaborations and to undertake cross-national comparative studies. To-date relatively few such studies have addressed migration, ethnicity and health, but their number is growing. While it is clear that divergent approaches to such comparative research are emerging, public health researchers have not so far given considered attention to the opportunities and challenges presented by such work. This paper contributes to this debate by drawing on the experience of a recent study focused on maternal health in Canada, Germany and the UK. Discussion: The paper highlights various ways in which cross-national comparative research can potentially enhance the rigour and utility of research into migration, ethnicity and health, including by: forcing researchers to engage in both ideological and methodological critical reflexivity; raising awareness of the socially and historically embedded nature of concepts, methods and generated 'knowledge'; increasing appreciation of the need to situate analyses of health within the wider socio-political setting; helping researchers (and research users) to see familiar issues from new perspectives and find innovative solutions; encouraging researchers to move beyond fixed 'groups' and 'categories' to look at processes of identification, inclusion and exclusion; promoting a multi-level analysis of local, national and global influences on migrant/minority health; and enabling conceptual and methodological development through the exchange of ideas and experience between diverse research teams. At the same time, the paper alerts researchers to potential downsides, including: significant challenges to developing conceptual frameworks that are meaningful across contexts; a tendency to reify concepts and essentialise migrant/minority 'groups' in an effort to harmonize across countries; a danger that analyses are superficial, being restricted to independent country descriptions rather than generating integrated insights; difficulties of balancing the need for meaningful findings at country level and more holistic products; and increased logistical complexity and costs. Summary: In view of these pros and cons, the paper encourages researchers to reflect more on the rationale for, feasibility and likely contribution of proposed cross-national comparative research that engages with migration, ethnicity and health and suggests some principles that could support such reflection.

The citation management program Zotero is a wonderful tool for researchers everywhere. Citations from the web may be "grabbed" simply by clicking on a in your web browser address bar. The citation information displayed on the screen is then saved to your Zotero collection with little or no additional effort. However, for this to work, each and every website must either follow standardized metadata guidelines, or must have its own personal "translator" that tells Zotero which words on the screen correspond with which bibliographic fields. Computers are stupid; translators make them smart. Most users who know about the citation capture feature are enthralled by it and want more. The Zotero forums receive multiple requests daily from users hoping their favourite site will be given this capability. Unfortunately, there just aren't enough Zotero programmers around to keep up with the demand for translators, and more intensive coding-projects take priority. Luckily, Zotero translators are fairly easy to create (as far as computer programming goes). This guide seeks to help take some of that load away from the Zotero staff by teaching the community of Zotero users how to create their own translators and to share them with others.

Although widely used, the term repellency needs to be employed with care when applied to ticks and other periodic or permanent ectoparasites. Repellency has classically been used to describe the effects of a substance that causes a flying arthropod to make oriented movements away from its source. However, for crawling arthropods such as ticks, the term commonly subsumes a range of effects that include arthropod irritation and consequent avoiding or leaving the host, failing to attach, to bite, or to feed. The objective of the present article is to highlight the need for clarity, to propose consensus descriptions and methods for the evaluation of various effects on ticks caused by chemical substances.