Temperature thresholds for surface blistering of platinum and stainless steel exposed to curium-242 alpha radiations

Implantation of helium in materials exposed to alpha-emitting radionuclides such as /sup 242/Cm causes surface blistering at elevated temperatures. The temperature thresholds for such blistering are of practical importance to the selection of suitable container materials for radionuclides, and are of fundamental interest with regard to the mechanisms of helium blistering of materials in radiation environments. The purpose of this investigation was to establish temperature thresholds for surface blistering of platinum and stainless-steel container materials by post-irradiation heating of specimens exposed at room temperature to alpha particles from an external /sup 242/Cm source. These thresholds were compared with (1) the analogous temperature thresholds for surface blistering of materials exposed to external beams of accelerator helium ions, and (2) thresholds for swelling and grain-boundary cracking of materials in which helium is generated internally by (n,..cap alpha..) reactions during reactor exposures

Management of New Production Reactor waste streams at Savannah River

To ensure the adequacy of available facilities, the disposition of the several waste types generated in support of a heavy-water NPR operation at the Savannah River Site were projected through waste- treatment and disposal facilities after the year 2000. Volumes of high-level, low-level radioactive, TRU, hazardous, mixed and non-radioactive waste were predicted for early assessments of environmental impacts and to provide a baseline for future waste-minimization initiatives. Life-cycle unit costs for disposal of the waste, adjusted to reflect waste management capabilities in the NPR operating time frame, were developed to evaluate the economic effectiveness of waste-minimization activities in the NPR program

Anaesthesia of three young grey seals (Halichoerus grypus) for fracture repair

Three young grey seals (Halichoerus grypus) were presented separately for fracture repair to the veterinary teaching hospital of University College Dublin. The seals were premedicated with a combination of pethidine, midazolam and atropine; anaesthesia was induced with propofol via the front flipper vein and maintained with sevoflurane or isoflurane in oxygen. One of the seals did not breathe spontaneously after anaesthesia; a cardiac arrest, resulting in death, occurred after several hours of mechanical ventilation. Post-mortem examination revealed a severe lungworm infestation and parasitic pneumonia in this animal. The two other seals recovered uneventfully from anaesthesia

Quality of life in caregivers of patients with schizophrenia: A literature review

<p>Abstract</p> <p>Background</p> <p>A couple of decades ago, hospitals or psychiatric institutions were in charge of caring for patients with schizophrenia; however, nowadays this role is performed by one or more patient's relatives. Evidence shows that informal caregivers experience negative changes in their quality of life (QOL). The aim of this study is to review the main factors associated with the QOL of caregivers of people with schizophrenia.</p> <p>Methods</p> <p>A search through databases from journals published last decade between 1998 and 2008 was performed. In accordance with the inclusion criteria, titles and abstracts of citations obtained from the search were examined independently by two authors and irrelevant articles discarded. The full text of those studies considered relevant by either reviewer were obtained and assessed independently. Where differences of opinion rose they were resolved by discussion. Out of the 258 references, 37 were included in the review.</p> <p>Studies which assessed factors associated with caregivers of people with schizophrenia's quality of life were included and the information summarized.</p> <p>Results</p> <p>Evidence suggest that physical, emotional and economic distress affect negatively caregiver's QOL as a result of a number of unfulfilled needs such as, restoration of patient functioning in family and social roles, economic burden, lack of spare time, among other factors.</p> <p>Conclusion</p> <p>Decreased QOL may be associated with caregivers' burden, lack of social support, course of the disease and family relationships problems. In addition, in developing countries, QOL is affected by caregivers' economic burden. High quality research is needed in order to identify factors associated with QOL over time and testing the efficacy of interventions aiming to improve QOL in caregivers of patients with schizophrenia.</p

A phase II study of the vitamin D analogue Seocalcitol in patients with inoperable hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a common malignant tumour, which has a poor prognosis. Surgical resection can be curative but most patients are inoperable and most chemotherapy agents have minimal activity in this disease. Seocalcitol, a vitamin D analogue, induces differentiation and inhibits growth in cancer cell lines and in vivo. The vitamin D receptor is expressed in hepatocytes and more abundantly in HCC cells. In total, 56 patients with inoperable advanced HCC were included in an uncontrolled study of oral Seocalcitol treatment for up to 1 year ( with possible extension for responders). The dose was titrated according to serum calcium levels. The treatment effect was evaluated by regular CT scans. Out of 33 patients evaluable for tumour response, two had complete response (CR), 12 stable disease and 19 progressive disease. The CRs appeared after 6 and 24 months of treatment, and lasted for 29 and at least 36 months ( patient still in remission when data censored). Seocalcitol was well tolerated; the most frequent toxicity was hypercalcaemia and related symptoms. Most patients tolerated a daily dose of 10 mug of Seocalcitol. This is the first study showing activity, by reduction in tumour dimensions, of a differentiating agent in patients with an advanced bulky, solid tumour. Seocalcitol may have an effect in the treatment of HCC, especially in early disease when a prolonged treatment can be instituted. The survival benefit with or without tumour response should be determined in controlled studies

Ubiquitous healthy diatoms in the deep sea confirm deep carbon injection by the biological pump

The role of the ocean as a sink for CO2 is partially dependent on the downward transport of phytoplankton cells packaged within fast-sinking particles. However, whether such fast-sinking mechanisms deliver fresh organic carbon down to the deep bathypelagic sea and whether this mechanism is prevalent across the ocean requires confirmation. Here we report the ubiquitous presence of healthy photosynthetic cells, dominated by diatoms, down to 4,000 m in the deep dark ocean. Decay experiments with surface phytoplankton suggested that the large proportion (18%) of healthy photosynthetic cells observed, on average, in the dark ocean, requires transport times from a few days to a few weeks, corresponding to sinking rates (124–732 m d−1) comparable to those of fast-sinking aggregates and faecal pellets. These results confirm the expectation that fast-sinking mechanisms inject fresh organic carbon into the deep sea and that this is a prevalent process operating across the global oligotrophic ocean