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Aims: The debate on the funding and availability of cytotoxic drugs raises questions about the contribution of curative or adjuvant cytotoxic chemotherapy to survival in adult cancer patients.Materials and methods: We undertook a literature search for randomised clinical trials reporting a 5-year survival benefit attributable solely to cytotoxic chemotherapy in adult malignancies. The total number of newly diagnosed cancer patients for 22 major adult malignancies was determined from cancer registry data in Australia and from the Surveillance Epidemiology and End Results data in the USA for 1998. For each malignancy, the absolute number to benefit was the product of (a) the total number of persons with that malignancy; (b) the proportion or subgroup(s) of that malignancy showing a benefit; and (c) the percentage increase in 5-year survival due solely to cytotoxic chemotherapy. The overall contribution was the sum total of the absolute numbers showing a 5-year survival benefit expressed as a percentage of the total number for the 22 malignancies.Results: The overall contribution of curative and adjuvant cytotoxic chemotherapy to 5-year survival in adults was estimated to be 2.3% in Australia and 2.1% in the USA.Conclusion: As the 5-year relative survival rate for cancer in Australia is now over 60%, it is clear that cytotoxic chemotherapy only makes a minor contribution to cancer survival. To justify the continued funding and availability of drugs used in cytotoxic chemotherapy, a rigorous evaluation of the cost-effectiveness and impact on quality of life is urgently required. [Copyright &y& Elsevier]

Classical radiation pneumonitis has been described after single dose whole lung irradiation in experimental animals where above a threshold dose of irradiation, there is a sigmoid dose response curve with increasing morbidity and mortality. After clinical fractionated irradiation, however, acute radiation pneumonitis consisting of cough shortness of breath and patchy radiological changes, occurs in <10% of patients, has dyspnoea out of proportion to the volume of lung irradiated and usually resolves completely without long-term effects. There is increasing evidence that this represents a bilateral lymphocytic alveolitis or hypersensitivity pneumonitis and has been termed sporadic pneumonitis. Late radiation toxicity results in pulmonary fibrosis. This is a consequence of repair, which is initiated by tissue injury within the radiation portal. It follows release of chemotactic factors for fibroblasts including transforming growth factor-beta, fibronectin and platelet derived growth factor. Radiation fibrosis is the clinically more significant syndrome for patients. It may result in progressive dyspnoea and mortality in patients. The most predictable change in laboratory lung function tests is a decrease in transfer factor due to damage at the capillary-alveolar level. It also results in decreased lung compliance, which will affect the total lung capacity and the forced vital capacity. The forced expiratory volume in 1 s is less affected, although this seems to depend on the volume of lung irradiated. There is also a decrease in perfusion in the irradiated lung. Radiation fibrosis seems to depend, amongst other factors, on the volume of lung, which is irradiated above a threshold of 20–30 Gy. The morbidity of radiation fibrosis may therefore be minimized by the use of dose volume histogram to minimize the volume of normal lung irradiated in patients at high risk, e.g., patients with who present with poor lung function. The importance of the baseline perfusion in the irradiated areas continues to be studied. [Copyright &y& Elsevier]

The recent installation of a Multi-Reflection Time-of-Flight (MR-TOF) isobar separator at the CARIBU facility has the promising potential to significantly improve the mass separation and selection of short-lived neutron-rich beams. Ions cycled in the km-long isochronous trajectories between two electrostatic mirrors can be separated to high levels of mass-resolving power within a short time (tens of ms). The installation process is described and results from the first operation are discussed. Following an optimization of the mirror voltages a mass-resolving power of 6.8 · 10 4 was achieved and a separation of isobars was demonstrated. The higher purity beams provided by the MR-TOF and delivered to the Canadian Penning Trap (CPT) will provide access to further measurements of neutron-rich nuclei along the astrophysical r -process path. [ABSTRACT FROM AUTHOR]

A centrifugal cryogenic pump has been designed at Argonne National Laboratory to circulate liquid nitrogen (LN 2 ) in a closed circuit allowing the recovery of excess fluid. The pump can circulate LN 2 at rates of 2–10 L/min, into a head of 0.5–3 m. Over four years of laboratory use the pump has proven capable of operating continuously for 50–100 days without maintenance. [ABSTRACT FROM AUTHOR]

Degradation of cliff-top habitats due to industrial activity is infrequent, leading to unique challenges when activity ceases and a site requires remediation. Dounreay, an ex-nuclear power facility on the north coast of Scotland, is currently being decommissioned prior to complete demolition of all buildings. A small area of the site will then be covered in a 1000 mm capping layer to prevent contamination of bioreceptors at the surface from below ground contaminants. Topsoil replacement is frequently used in such instances, however, limited availability of topsoil in the region means that other materials are sought to mitigate against undesirable ecological and economic costs. We tested combinations of differentially graded rocks and topsoil to assess their suitability in supporting re-vegetation. The vegetation response was measured as richness (numbers of species), ground cover, species diversity, and biomass. Wider ecosystem function was assessed by measuring invertebrate numbers and diversity, and comparing these to locally relevant reference site data. Fine crushed rock supported native vegetation establishment and growth, though cover, diversity, and biomass (after three years) were significantly below levels found when topsoil was used instead. Initial establishment on the fine crushed rock may be limited by the low water retention and nutrient availability of the material. We suggest that a rich heterogeneous habitat able to support a wide range of native vegetation and invertebrates may be provided by mixing topsoil with the fine crushed rock in the future. This mosaic combination would also allow for significant ecological and financial cost savings (against topsoil only remediation) and could be tested on larger scales. • Vegetation returns on crushed rock surface layer without topsoil addition. • Invertebrate numbers recover well on crushed rock surface vegetation. • Opportunist colonisers generally outcompeted by targeted sown vegetation. • Phosphate addition could speed up vegetation recovery on crushed rock surface layer. • Remediation using fine crushed rock could reduce financial and carbon costs. [ABSTRACT FROM AUTHOR]