Agreement between methods of measurement with multiple observations per individual

Limits of agreement provide a straightforward and intuitive approach to agreement between different methods for measuring the same quantity. When pairs of observations using the two methods are independent, i.e., on different subjects, the calculations are very simple and straightforward. Some authors collect repeated data, either as repeated pairs of measurements on the same subject, whose true value of the measured quantity may be changing, or more than one measurement by one or both methods of an unchanging underlying quantity. In this paper we describe methods for analysing such clustered observations, both when the underlying quantity is assumed to be changing and when it is not

Comparisons against baseline within randomised groups are often used and can be highly misleading

<p>Abstract</p> <p>Background</p> <p>In randomised trials, rather than comparing randomised groups directly some researchers carry out a significance test comparing a baseline with a final measurement separately in each group.</p> <p>Methods</p> <p>We give several examples where this has been done. We use simulation to demonstrate that the procedure is invalid and also show this algebraically.</p> <p>Results</p> <p>This approach is biased and invalid, producing conclusions which are, potentially, highly misleading. The actual alpha level of this procedure can be as high as 0.50 for two groups and 0.75 for three.</p> <p>Conclusions</p> <p>Randomised groups should be compared directly by two-sample methods and separate tests against baseline are highly misleading.</p

Low-Velocity Halo Clouds

Models that reproduce the observed high-velocity clouds (HVCs) also predict clouds at lower radial velocities that may easily be confused with Galactic disk (|z| < 1 kpc) gas. We describe the first search for these low-velocity halo clouds (LVHCs) using IRAS data and the initial data from the Galactic Arecibo L-band Feed Array survey in HI (GALFA-HI). The technique is based upon the expectation that such clouds should, like HVCs, have very limited infrared thermal dust emission as compared to their HI column density. We describe our 'displacement-map' technique for robustly determining the dust-to-gas ratio of clouds and the associated errors that takes into account the significant scatter in the infrared flux from the Galactic disk gas. We find that there exist lower-velocity clouds that have extremely low dust-to-gas ratios, consistent with being in the Galactic halo - candidate LVHCs. We also confirm the lack of dust in many HVCs with the notable exception of complex M, which we consider to be the first detection of warm dust in HVCs. We do not confirm the previously reported detection of dust in complex C. In addition, we find that most Intermediate- and Low-Velocity clouds that are part of the Galactic disk have a higher 60 micron/100 micron flux ratio than is typically seen in Galactic HI, which is consistent with a previously proposed picture in which fast-moving Galactic clouds have smaller, hotter dust grains.Comment: 30 pages, 7 figures. Accepted to the Ap

Philosophical inquiry in a culturally diverse, faith-based community

This paper reports on collaborative research undertaken with the African Australian Christian Impact Centre (CIC) in Perth, Western Australia. It is part of a larger university philosophy outreach program in which the researchers seek to create opportunities for those on the educational and social margins, and young people, to engage in ‘doing philosophy’, and to learn from them about their experiences. We were interested to evaluate whether the collaborative philosophical inquiry methods we use in our university teaching could be beneficial outside of a formal educational setting, for members of the culturally diverse, faith-based community of CIC. In this multi-method evaluative study, we examined the extent to which participation in a series of Community of Inquiry (CoI) sessions improved or did not improve participants’ self-assessment of: (1) their competence and confidence in communicating with others in different contexts; (2) their competence and confidence as a ‘thinker’; and (3) their social competence and confidence. Our findings on ‘communication’ are discussed in this paper. The facilitated philosophical discussions led to insights about ‘speaking out’ and ‘listening’, particularly with respect to participants’ experiences of cultural and generational differences. We suggest that participation in CoI in a faith-based community setting has the potential to significantly increase confidence in communication skills, and lead to greater intergenerational, intercultural, and intercommunity sensitivity

A peculiar HI cloud near the distant globular cluster Pal 4

We present 21-cm observations of four Galactic globular clusters, as part of the on-going GALFA-HI Survey at Arecibo. We discovered a peculiar HI cloud in the vicinity of the distant (109 kpc) cluster Pal 4, and discuss its properties and likelihood of association with the cluster. We conclude that an association of the HI cloud and Pal 4 is possible, but that a chance coincidence between Pal 4 and a nearby compact high-velocity cloud cannot be ruled out altogether. New, more stringent upper limits were derived for the other three clusters: M 3, NGC 5466, and Pal 13. We briefly discuss the fate of globular cluster gas and the interaction of compact clouds with the Galactic Halo gas.Comment: Accepted for publication in MNRA

Environmental DNA Based Surveillance for the Highly Invasive Carpet Sea Squirt Didemnum vexillum : A Targeted Single-Species Approach

Funding Information: The authors would like to thank the site operators, owners and Solway Firth Partnership for allowing access and sample collection at studied sites visited during this study. Thanks also to Frank Armstrong, Katy Beaton, Maria Campbell, Pablo Dias, James Dooley, Judith Horrill, Nial McLeod, Warren Murray, Andrea Taylor, Joe Triscott, and Bill Turrell for contributing to field work and sample collection. The authors thank National Museums Scotland and particularly Fiona Ware for the loan of reference material (specimen register number NMS.Z.2015.82.8, 9 and 14 and NMS.Z.2018.2.2) which was used in the present study. KS thank the Japan Society for the Promotion of Science for post-doctoral fellowship funding.Peer reviewedPublisher PD

Battling Against Interfaith Relations in Israel: Religion, Therapy, and Social Services

One of the less studied aspects of the Israeli–Palestinian conflict is its demography. On the Jewish side, active steps are taken by the state to encourage Jewish immigration and Jewish births and discourage Jewish assimilation. As part of these efforts, the “problematic relationships” between Arab men and Jewish women from low socioeconomic background have become a high agenda item in public discussions in Israel during the last decade. I will examine here how the diagnostic category “girls at risk” and a therapeutic intervention employed by social services dealing with these couples helps maintaining the delicate balance between Jewish and democratic values. I will analyze these practices as a solution to a structural problem of the Jewish enclave in Israel

Computational Eulerian Hydrodynamics and Galilean Invariance

Eulerian hydrodynamical simulations are a powerful and popular tool for modeling fluids in astrophysical systems. In this work, we critically examine recent claims that these methods violate Galilean invariance of the Euler equations. We demonstrate that Eulerian hydrodynamics methods do converge to a Galilean-invariant solution, provided a well-defined convergent solution exists. Specifically, we show that numerical diffusion, resulting from diffusion-like terms in the discretized hydrodynamical equations solved by Eulerian methods, accounts for the effects previously identified as evidence for the Galilean non-invariance of these methods. These velocity-dependent diffusive terms lead to different results for different bulk velocities when the spatial resolution of the simulation is kept fixed, but their effect becomes negligible as the resolution of the simulation is increased to obtain a converged solution. In particular, we find that Kelvin-Helmholtz instabilities develop properly in realistic Eulerian calculations regardless of the bulk velocity provided the problem is simulated with sufficient resolution (a factor of 2-4 increase compared to the case without bulk flows for realistic velocities). Our results reiterate that high-resolution Eulerian methods can perform well and obtain a convergent solution, even in the presence of highly supersonic bulk flows.Comment: Version accepted by MNRAS Oct 2, 2009. Figures degraded. For high-resolution color figures and movies of the numerical simulations, please visit http://www.astro.caltech.edu/~brant/Site/Computational_Eulerian_Hydrodynamics_and_Galilean_Invariance.htm

GASKAP -- The Galactic ASKAP Survey

A survey of the Milky Way disk and the Magellanic System at the wavelengths of the 21-cm atomic hydrogen (HI) line and three 18-cm lines of the OH molecule will be carried out with the Australian Square Kilometre Array Pathfinder telescope. The survey will study the distribution of HI emission and absorption with unprecedented angular and velocity resolution, as well as molecular line thermal emission, absorption, and maser lines. The area to be covered includes the Galactic plane (|b|< 10deg) at all declinations south of delta = +40deg, spanning longitudes 167deg through 360deg to 79deg at b=0deg, plus the entire area of the Magellanic Stream and Clouds, a total of 13,020 square degrees. The brightness temperature sensitivity will be very good, typically sigma_T ~ 1 K at resolution 30arcsec and 1 km/s. The survey has a wide spectrum of scientific goals, from studies of galaxy evolution to star formation, with particular contributions to understanding stellar wind kinematics, the thermal phases of the interstellar medium, the interaction between gas in the disk and halo, and the dynamical and thermal states of gas at various positions along the Magellanic Stream.Comment: 45 pages, 8 figures, Pub. Astron. Soc. Australia (in press

Associations of negative affective biases and depressive symptoms in a community-based sample

Acknowledgements. We thank professor Jonathan Roiser (University College London, UK) and professor emeritus Ian Deary (University of Edinburgh, UK) for their input on task selection and statistical analysis. We also acknowledge all researchers who have contributed to the collection of data for the current study. Most importantly, we would like to thank all participants of Generation Scotland, and particularly those of the STRADL subcohort, for their participation in the research. Financial support. Stratifying Resilience and Depression Longitudinally is supported by the Wellcome Trust through a Strategic Award (Grant No. 104036/Z/14/Z) and through an Investigator Award (Grant No. 220857/Z/ 20/Z). The Chief Scientist Office of the Scottish Government Health Department (Grant No. CZD/16/6), Scottish Funding Council (Grant No. HR03006) and Wellcome Trust (Grant No. 216767/Z/19/Z) provided core support for Generation Scotland.Peer reviewedPublisher PD