The processes taking place in the outermost reaches of spiral disks (the 'proto-disk') are intimately connected to the build-up of mass and angular momentum in galaxies. The thinness of spiral disks suggests that the activity is mostly quiescent and presumably this region is fed by cool flows coming into the halo from the intergalactic medium. While there is abundant evidence for the presence of a circumgalactic medium (CGM) around disk galaxies as traced by quasar absorption lines, it has been very difficult to connect this material to the outer gas disk. This has been a very difficult transition region to explore because baryon tracers are hard to observe. In particular, H I disks have been argued to truncate at a critical column density (N H > ∼ 10 19.5 cm −2 at 30 kpc for an L galaxy) where the gas is vulnerable to the external ionizing background. But new deep observations of nearby L spirals (e.g. Milky Way, NGC 2997) suggest that H I disks may extend much further than recognised to date, up to 60 kpc at N H ≈ 10 18 cm −2 . Motivated by these observations, here we show that a clumpy outer disk of dense clouds or cloudlets is potentially detectable to much larger radii and lower H I column densities than previously discussed. This extended proto-disk component is likely to explain some of the Mg II forest seen in quasar spectra as judged from absorption-line column densities and kinematics. We fully anticipate that the armada of new radio facilities and planned H I surveys coming online will detect this extreme outer disk (scree) material. We also propose a variant on the successful 'Dragonfly' technique to go after the very weak Hα signals expected in the proto-disk region.

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The present study investigated the validity of the 25-item Driving Anger Expression Inventory (DAX) as well as the role of sex and gender-roles in relation to the expression of driving anger in a sample of 378 French drivers (males=38%, M=32.9years old). Confirmatory Factor Analysis supported the four-factor structure of the 25-item DAX (Adaptive/Constructive Expression; Use of the Vehicle to Express Anger; Verbal Aggressive Expression and Personal Physical Aggressive Expression) and two of the three aggressive factors were found to have significant positive relationships with driving anger, while adaptive/constructive expression was negatively related to driving anger. Use of the vehicle to express anger was not significantly related to crash involvement, but was significantly related to all other crash-related conditions (traffic tickets, loss of concentration, loss of control of the vehicle, near crash). The presence of feminine traits, but not sex, was predictive of adaptive/constructive behaviours, while masculine traits predicted more frequent verbal aggressive expression, use of the vehicle to express anger, personal physical aggressive expression and total aggressive expression. This finding may account for the inconsistent relationship found between driving anger and sex in previous research. This research also found that the 25-item DAX is a valid tool to measure the expression of driving anger and that the endorsement of masculine traits are related to more aggressive forms of driving anger expression.

Caring for young infants can be stressful. Non-accidental brain or head injury (shaken baby syndrome) is a result of parental stress, and a lack of knowledge of how to respond to a crying infant and the dangers of shaking a child. This article demonstrates the value of international collaboration in projects to prevent child maltreatment. It includes reports of prevention of shaken baby syndrome programmes in Australia, Hungary, Greece, Brazil and Turkey.

This research investigated how behaviours and attitudes of bicycle riders influence crash frequency and severity. The study recruited 1102 Australian bicycle riders for an online survey. The survey comprised questions on demographics, frequency of riding and the number and severity of traffic crashes during the last five years. The survey included the Cycling Behaviour Questionnaire and the Cyclist Risk Perception and Regulation Scale. Overall, there were low levels of errors and violations reported by participants indicating that these behaviours were on average never or rarely exhibited while riding a bicycle. Conversely, participants reported high levels of engagement in positive behaviours and reported high levels of traffic rule knowledge and risk perception. Higher rates of violations and errors were associated with increased crash likelihood, while higher rates of positive behaviours were associated with reduced rates of crash involvement in a period of 5 years. The findings highlight the relationship between errors, total crashes and crash severity Further promotion of positive behaviours amongst riders may also help to reduce the risk of crashes.

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