The Cambridge-Cambridge ROSAT Serendipity Survey - I. X-ray-luminous galaxies

We report on the first results obtained from a new optical identification programme of 123 faint X-ray sources with $S$(0.5--2$\,{\rm keV)}>2\times 10^{-14}\,$erg$\,$s$^{-1}\,$cm$^{-2}\,$ serendipitously detected in {\it ROSAT} PSPC pointed observations. We have spectroscopically identified the optical counterparts to more than 100 sources in this survey. Although the majority of the sample (68 objects) are QSOs, we have also identified 12 narrow emission line galaxies which have extreme X-ray luminosities ($10^{42} < L_{\rm X} < 10^{43.5}\,$erg$\,$s$^{-1}$). Subsequent spectroscopy reveals them to be a mixture of starburst galaxies and Seyfert 2 galaxies in approximately equal numbers. Combined with potentially similar objects identified in the {\it Einstein} Extended Medium Sensitivity Survey, these X-ray-luminous galaxies exhibit a rate of cosmological evolution, $L_{\rm X} \propto (1+z)^{2.5\pm1.0}$, consistent with that derived for X-ray QSOs. This evolution, coupled with the steep slope determined for the faint end of the X-ray luminosity function ($\Phi(L_{\rm X}) \propto L_{\rm X}^{-1.9}$), implies that such objects could comprise 15--35 per cent of the soft (1--2$\,$keV)Comment: Accepted for publication in MNRAS. 7 pages including 5 figures; uuencoded compressed postscript; RGO-21

“’Benevolent Plans Meritoriously Applied’: How Missouri Almost Became an Indian Nation, 1803–1811”

One aspect of western development—and of early Missouri territorial history—was figuring out how native peoples fit into visions of the West, as B. J. McMahon suggests

VLA neutral hydrogen imaging of compact groups

Images of the neutral hydrogen (H I) in the direction of the compact groups of galaxies, HCG 31, HCG 44, and HCG 79 are presented. The authors find in HCG 31 and HCG 79, emission contained within a cloud much larger than the galaxies as well as the entire group. The H I emission associated with HCG 44 is located within the individual galaxies but shows definite signs of tidal interactions. The authors imaged the distribution and kinematics of neutral hydrogen at the two extremes of group sizes represented in Hickson's sample. HCG 44 is at the upper limit while HCG 18, HCG 31, and HCG 79 are at the lower end. Although the number of groups that have been imaged is still very small, there may be a pattern emerging which describes the H I morphology of compact groups. The true nature of compact groups has been the subject of considerable debate and controversy. The most recent observational and theoretical evidence strongly suggests that compact groups are physically dense, dynamical systems that are in the process of merging into a single object (Williams and Rood 1987, Hickson and Rood 1988, Barnes 1989). The neutral hydrogen deficiency observed by Williams and Rood (1987) is consistent with a model in which frequent galactic collisions and interactions have heated some of the gas during the short lifetime of the group. The H I disks which are normally more extended than the luminous ones are expected to be more sensitive to collisions and to trace the galaxy's response to recent interactions. Very Large Array observations can provide in most cases the spatial resolution needed to confirm the dynamical interactions in these systems

New Limits on the Polarized Anisotropy of the Cosmic Microwave Background at Subdegree Angular Scales

We update the limit from the 90 GHz PIQUE ground-based polarimeter on the magnitude of any polarized anisotropy of the cosmic microwave radiation. With a second year of data, we have now limited both Q and U on a ring of 1 degree radius. The window functions are broad: for E-mode polarization, the effective l is = 191 +143 -132. We find that the E-mode signal can be no greater than 8.4 microK (95% CL), assuming no B-mode polarization. Limits on a possible B-mode signal are also presented.Comment: 4 pages, 3 figures, submitted to Astrophysical Journal Letter

Mentoring as a career guidance activity: Fostering non-traditional career exploration for girls

This paper reports on a short term mentoring project conducted in the Australian state of Queensland to foster non-traditional career exploration for girls in the communications/informa - tion technology industry. The aim of the study was to evaluate the possibilities of a short term mentoring program to foster girls’interest in a non-traditional industry. In addition it sought to exam - ine the viability of mentoring as a career guidance activity in schools. The findings indicate that mentoring could be a worthy addition to the repertoire of career guidance activities offered by schools and that it is a valuable process in promoting non-traditional career exploration for girls

Destruction of toxic and environmental harmful gases

Environmental and Occupational Health and Safety or OH&amp;S issues have influenced the focus to capture / destroy toxic and environmental harmful gases expelled from fumigated storage. These storages are aerated to Threshold Limit Value (TLV) levels at the completion of fumigation to ensure it is safe for human reentry. Most fumigants by design are toxic and some have additional environmental hazards. The once universal fumigant, methyl bromide (CH3Br), while restricted by the Montreal Protocol because it is an ozone depletor, is still used commercially in tonnage quantities. The use of CH3Br is now mostly restricted to Quarantine Pre-Shipment (QPS) fumigations. The CH3Br dose level is approximately 10.000 ppm and the recommended maximum respiratory level is 5 ppm. The universal fumigant gas, phosphine (PH3), a very toxic gas, has a recommended TLV of 0.3 ppm. The sterilant, ethylene oxide (EtO), a known carcinogen, could have niche fumigation-sterilisation applications if the aerated gas could be destroyed. The use of heat to decompose toxic gases can involve the extracted contaminated air being fed into a burner where the hot zone destroys and decomposes the vulnerable fumigant gas. While flame burning at high temperature pyrolysis is 100% effective with EtO, most fumigants will form acidic by-product. Other issues include the need to re-locate capture and destruction equipment to service multiple locations and the large dilution required to reach TLV levels. A current alternative consists of adsorbing fumigants on activated charcoal. The spent activated charcoal requires chemical processing and or burial. There are cost issues with the initial purchase of the activated charcoal and post-treatment chemical processing of the adsorbed fumigant. Another disposal option is the burial of the spent charcoal in landfill sites. The ongoing safe use of fumigants is critical to important export industries especially the large volume bulk grain and export timber market.Keywords: Fumigants, Capture, Destruction, Incineration, Acidic reactants

Recent Developments in Federal Income Taxation: The Year 2004

This recent developments outline discusses, and provides context to understand the significance of, the most important judicial decisions and administrative rulings and regulations promulgated by the Internal Revenue Service and Treasury Department during 2004 - and sometimes a little farther back in time if we find the item particularly humorous or outrageous. Most Treasury Regulations, however, are so complex that they cannot be discussed in detail and, anyway, only a devout masochist would read them all the way through; just the basic topic and fundamental principles are highlighted. Amendments to the Internal Revenue Code generally are not discussed except to the extent that (1) they are of major significance, (2) they have led to administrative rulings and regulations, (3) they have affected previously issued rulings and regulations otherwise covered by the outline, or (4) they provide Marty the opportunity to mock our elected representatives. The outline focuses primarily on topics of broad general interest (to the two of us, at least) - income tax accounting rules, determination of gross income, allowable deductions, treatment of capital gains and losses, corporate and partnership taxation, exempt organizations, and procedure and penalties. It deals summarily with qualified pension and profit sharing plans, and generally does not deal with international taxation or specialized industries, such as banking, insurance, and financial services. Please read this outline at your own risk; we take no responsibility for any misinformation in it, whether occasioned by our advancing ages or our increasing indifference as to whether we get any particular item right. Any mistakes in this outline are Marty\u27s responsibility; any political bias or offensive language is Ira\u27s