A third HI 21-cm absorption system in the sight-line of MG J0414+0534: A redshift for Object X?

We report the detection of a third HI 21-cm absorber in the sight-line towards the z=2.64 quasar MG J0414+0534 (4C +05.19). In addition to the absorption at the host redshift and in the z=0.96 gravitational lens, we find, through a decimetre-wave spectral scan towards this source, strong absorption at z=0.38. We believe this may be associated with "Object X", an additional feature apparent in the field of the lensing galaxy and lensed images, on the basis of its close proximity to the quasar images and the possible detection of the [OIII] doublet in a published optical spectrum. If real, the strength of the [OIII] emission would suggest the presence of an active galactic nucleus, or a gas-rich galaxy undergoing rapid star formation, either of which is consistent with the strong outflows apparent in the 21-cm spectrum. Although this is the strongest intervening 21-cm absorber yet found, simultaneous observations failed to detect any of the 18-cm OH lines at the 21-cm redshift. This suggests that, as for the lensing galaxy, this is not the primary location of the intervening material responsible for the very red colour of MG J0414+0534.Comment: 5 pages, accepted by MNRAS Letter

Protecting Government Defense Contracting with a Purpose: Interpreting Civil Liability Under the Anti-Kickback Act

The Department of Defense awards over $600 billion in government defense contracts to private contractors every year. The magnitude of these awards and the structure of defense contracts place the government at serious risk if fraud and misrepresentation are not adequately regulated and prosecuted. The Anti-Kickback Act of 1986 seeks to protect the government from fraud by imposing damages on prime contractors that either accept kickbacks or include the cost of kickbacks in their contract prices. The Act’s civil liability provision provides for direct and vicarious liability against prime contractor corporations whose employees or subcontractors engage in kickback activity. Recently, conflicting interpretations have surfaced regarding the extent of vicarious liability damages under the Act’s civil liability provision. This Note argues that the textual ambiguity and inconclusive legislative history surrounding the civil liability provision require that the provision be interpreted and applied in light of the Act’s purpose and goals. Accordingly, this Note argues that the civil liability provision should be interpreted to limit vicarious liability damages against prime contractor corporations. This interpretation satisfies the Act’s purpose and goals and avoids the substantial risks created by expanding vicarious liability damages. Most significantly, limiting vicarious liability damages appropriately protects the government’s interest, maintains the role of prime contractor corporations, and preserves the market for government defense contracts

Training health visitors in cognitive behavioural and person-centred approaches for depression in postnatal women as part of a cluster randomised trial and economic evaluation in primary care: the PoNDER trial

Aim: This paper aims to describe the training preparation for health visitors who took part in the intervention arm of a cluster randomised controlled trial and economic evaluation of training for health visitors – the POstNatal Depression Economic evaluation and Randomised (the PoNDER) trial. A secondary aim is to make available, by electronic links, the training manuals developed for and used for the cognitive behavioural approach (CBA) and the person-centred approach (PCA) training for the health visitors. The paper is of relevance to health visitors, general practitioners, nurse practitioners, midwives, clinical psychologists, mental health nurses, community psychiatric nurses, counsellors, and service commissioners. Background: The trial clinical outcomes have been published, indicating the pragmatic effectiveness of the package of training for health visitors to identify depressive symptoms and provide a psychologically informed intervention. The training was associated with a reduction in depressive symptoms at six months postnatally among intervention group women and some evidence of a benefit for the intervention group for some of the secondary outcomes at 18 months follow-up. Methods: The two experimental interventions examined in the PoNDER trial built upon promising work on the potential for psychological interventions to help women recover from postnatal depression as an alternative to pharmaceutical interventions and to address the limitations of previous research in the area. Findings: The package of health visitor training comprised the development of clinical skills in assessing postnatal women and identifying depressive symptoms, and the delivery of a CBA or a PCA for eligible women. This was the largest trial a health visitor intervention and of postnatal depression ever conducted. We are aware of no other rigorously performed trial that has published details of an extensively tested training programme for the benefit of health-care professionals and clients

A fourth HI 21-cm absorption system in the sight-line of MG J0414+0534: a record for intervening absorbers

We report the detection of a strong HI 21-cm absorption system at z=0.5344, as well as a candidate system at z=0.3389, in the sight-line towards the z=2.64 quasar MG J0414+0534. This, in addition to the absorption at the host redshift and the other two intervening absorbers, takes the total to four (possibly five). The previous maximum number of 21-cm absorbers detected along a single sight-line is two and so we suspect that this number of gas-rich absorbers is in some way related to the very red colour of the background source. Despite this, no molecular gas (through OH absorption) has yet been detected at any of the 21-cm redshifts, although, from the population of 21-cm absorbers as a whole, there is evidence for a weak correlation between the atomic line strength and the optical--near-infrared colour. In either case, the fact that so many gas-rich galaxies (likely to be damped Lyman-alpha absorption systems) have been found along a single sight-line towards a highly obscured source may have far reaching implications for the population of faint galaxies not detected in optical surveys, a possibility which could be addressed through future wide-field absorption line surveys with the Square Kilometre Array.Comment: Accepted by ApJ Letter

Migration and Cultural Change: A Role for Gender and Social Networks?

From the Introduction: To incorporate the insights from the literature on gender and migration, we focus upon three key concepts that have emerged regarding the role of social networks, households, and communities for affecting migration processes. The three key concepts we interrogate are: “social embeddedness” (Portes and Sensenbrenner 1993), “circular and cumulative causation” (Massey 1990), and “relative deprivation” (Stark 1991). We propose considering these three concepts through the lens of a third area of research, the sociology of culture, and we draw upon ideas about identity formation, trust, and normative expectations. Our empirical examples come primarily from Thailand where we draw upon both secondary and primary data but also from secondary data from Latin America and the Caribbean migrant experiences. In our effort to demonstrate that social networks and gender are essential elements for understanding migration and cultural change, our discussion refers to international, internal, permanent, and temporary migration

A survey for redshifted molecular and atomic absorption lines - II. Associated HI, OH and millimetre lines in the z >~ 3 Parkes quarter-Jansky flat-spectrum sample

We present the results of a z>2.9 survey for HI 21-cm and molecular absorption in the hosts of radio quasars using the GMRT and the Tidbinbilla 70-m telescope. Previously published searches, which are overwhelmingly at redshifts of z<1, exhibit a 42% detection rate (31 out of 73 sources), and the inclusion of our survey yields a 17% detection rate (2 out of 12 sources) at z>2.5. We therefore believe that our high redshift selection is responsible for our exclusive non-detections, and find that at ultra-violet luminosities of >10e23 W/Hz, 21-cm absorption has never been detected. We also find this to not only apply to our targets, but also those at low redshift exhibiting similar luminosities, giving zero detections out of a total of 16 sources over z=0.24 to 3.8. This is in contrast to the < 10e23 W/Hz sources where there is a near 50% detection rate of 21-cm absorption. The mix of 21-cm detections and non-detections is currently attributed to orientation effects, where according to unified schemes of active galactic nuclei, 21-cm absorption is more likely to occur in sources designated as radio galaxies (type-2 objects, where the nucleus is viewed through dense obscuring circumnuclear gas) than in quasars(type-1 objects, where we have a direct view to the nucleus). However, due to the exclusively high ultra-violet luminosities of our targets it is not clear whether orientation effects alone can wholly account for the distribution, although there exists the possibility that the large luminosities are indicative of a changing demographic of galaxy types. We also find that below luminosities of ~10e23 W/Hz, both type-1 and type-2 objects have a 50% likelihood of exhibiting 21-cm absorption.Comment: 21 pages, accepted by MNRA

HI and OH absorption in the lensing galaxy of MG J0414+0534

We report the detection of \HI 21-cm absorption in the $z=0.96$ early-type lensing galaxy towards MG J0414+0534 with the Green Bank Telescope. The absorption, with total $N_{\rm HI}=1.6 \times 10^{18} (T_{\rm s}/f) {\rm cm}^{-2}$, is resolved into two strong components, probably due to the two strongest lens components, which are separated by 0.4\arcsec. Unlike the other three lenses which have been detected in \HI, J0414+0534 does not exhibit strong OH absorption, giving a OH/\HI column density ratio of N_{\rm OH}/N_{\rm HI}\lapp10^{-6} (for $T_{\rm s}=100$ K, $T_{\rm x}=10$ K and $f_{\rm HI}=f_{\rm OH}=1$). This underabundance of molecular gas may indicate that the extreme optical--near-IR colour ($V-K=10.26$) along the line-of-sight is not due to the lens. We therefore suggest that despite the strong upper limits on molecular absorption at the quasar redshift, as traced by millimetre lines, the extinction occurs primarily in the quasar host galaxy.Comment: Accepted by MNRAS Letters, 5 (and a bit) pages, 5 figure

Effects of anode material on arcjet performance

Anodes fabricated from four different materials were tested in a modular arcjet thruster at 1 kW power level on nitrogen/hydrogen mixtures. A two-percent thoriated tungsten anode served as the control. Graphite was chosen for its ease in fabrication, but experienced severe erosion in the constrictor and diverging side. Hafnium carbide and lanthanum hexaboride were chosen for their low work functions but failed due to thermal stress and reacted with the propellant. When compared to the thoriated tungsten nozzle, thruster performance was significantly lower for the lanthanum hexaboride insert and the graphite nozzle, but was slightly higher for the hafnium carbide nozzle. Both the lanthanum hexaboride and hafnium carbide nozzle operated at higher voltages. An attempt was made to duplicate higher performance hafnium carbide results, but repeated attempts at machining a second anode insert were unsuccessful. Graphite, hafnium carbide, and lanthanum hexaboride do not appear viable anode materials for low power arcjet thrusters