Determination of the henrian activity coefficient of sodium in liquid magnesium

The temperature-dependent Henrian activity coefficient of Na in liquid Mg in the very dilute range has been determined from measurements of equilibrium concentrations of Na in liquid Mg in contact with NaCl-MgCl₂ melts of different compositions and temperatures in the range 650 to 790 °C. The term A in the equation RT in γ _Na = A was fitted to the experimental results using the equilibrium constant for the reaction 2NaCl (l) + Mg (l) = MgCl₂ (l) + 2Na (l) and thermodynamic data for the NaCl-MgCl₂ melt. The obtained γ _Na is compared to previously measured activity coefficients and activity coefficients calculated from existing solubility data for the Na-Mg system.     

Solubility of chloride in molten magnesium metal

The solubilities of chloride (Cl) in liquid magnesium (Mg) have been determined from the analysis of quenched samples of liquid Mg equilibrated with NaCl-MgCl₂ melts of different compositions at temperatures in the range 650–790 °C. As an example, the solubility of Cl in liquid Mg in contact with pure MgCl₂ at 735 °C was found to be approximately 18 ppm. The Cl solubility was found to be proportional to the square root of the MgCl₂ activity in the NaCl-MgCl₂ melt, indicating that MgCl₂ dissolved according to the reaction 0.5MgCl₂ + 0.5Mg(l) = MgCl (in Mg). The temperature dependency of the solubility also was measured. Thermodynamic values related to the dissolution of MgCl₂ in liquid Mg have been estimated.     

Determination of the henrian activity coefficient of sodium in liquid magnesium

The temperature-dependent Henrian activity coefficient of Na in liquid Mg in the very dilute range has been determined from measurements of equilibrium concentrations of Na in liquid Mg in contact with NaCl-MgCl₂ melts of different compositions and temperatures in the range 650 to 790 °C. The term A in the equation RT in γ _Na = A was fitted to the experimental results using the equilibrium constant for the reaction 2NaCl (l) + Mg (l) = MgCl₂ (l) + 2Na (l) and thermodynamic data for the NaCl-MgCl₂ melt. The obtained γ _Na is compared to previously measured activity coefficients and activity coefficients calculated from existing solubility data for the Na-Mg system.     

The influence of meteorological parameters on soil radon levels in permeable glacial sediments

The influence of meteorological parameters on soil radon concentrations in a permeable ice-marginal deposit in Kinsarvik, Norway, was investigated based on continuous measurements of soil radon concentrations, temperature, precipitation, wind speed, wind direction, air pressure and soil moisture content over a period of 10 months. The results show that the soil radon concentrations exhibit distinct seasonal and diurnal variations that predominantly are caused by changes in air temperature. Air flows between areas of different elevation occur in the ice-marginal deposit due to temperature differences between soil air and atmospheric air, and instantaneous changes in air flow direction were recorded when the atmospheric air temperature reached the average annual air temperature. Air pressure was found to be the second most important parameter influencing soil radon concentrations, while no apparent effect of precipitation, wind speed, wind direction or soil moisture was observed. Seasonal variations in indoor and soil radon levels were also investigated in a glaciofluvial deposit located 40 km southwest of Kinsarvik, and the close correlation between the seasonal variation patterns observed in the two areas suggests that the results of the Kinsarvik study also might be applicable to other areas of highly permeable building grounds where differences in terrain elevation exist.     

Stomach cancer. A 10-year material with emphasis on early cancer

Between 1982 and 1991, 112 patients were treated for gastric cancer at Harstad Hospital in Northern Norway. Early gastric cancer accounted for 20% of all the adenocarcinomas (110), which is high compared with figures from other western studies. The role of endoscopy for detecting early gastric cancer is discussed. The five year survival rate after radical surgery was found to be significantly higher for patients with early gastric cancer than for patients who underwent curative surgery for either infiltrative or regional cancer. For patients with a tumour that had invaded the regional lymph nodes the five year survival rate was only 10%. This result can be improved by more extended lymph node dissection. The perioperative mortality rate (8%) was usually a result of severe cancer cachexia or underlying cardial disease, and not anastomotic leakage. The results as regards the cure of early gastric cancer are comparable with those described in other studies.     

Platelet Microparticles Decrease Daunorubicin-Induced DNA Damage and Modulate Intrinsic Apoptosis in THP-1 Cells

Platelets can modulate cancer through budding of platelet microparticles (PMPs) that can transfer a plethora of bioactive molecules to cancer cells upon internalization. In acute myelogenous leukemia (AML) this can induce chemoresistance, partially through a decrease in cell activity. Here we investigated if the internalization of PMPs protected the monocytic AML cell line, THP-1, from apoptosis by decreasing the initial cellular damage inflicted by treatment with daunorubicin, or via direct modulation of the apoptotic response. We examined whether PMPs could protect against apoptosis after treatment with a selection of inducers, primarily associated with either the intrinsic or the extrinsic apoptotic pathway, and protection was restricted to the agents targeting intrinsic apoptosis. Furthermore, levels of daunorubicin-induced DNA damage, assessed by measuring gH2AX, were reduced in both 2N and 4N cells after PMP co-incubation. Measuring different BCL2-family proteins before and after treatment with daunorubicin revealed that PMPs downregulated the pro-apoptotic PUMA protein. Thus, our findings indicated that PMPs may protect AML cells against apoptosis by reducing DNA damage both dependent and independent of cell cycle phase, and via direct modulation of the intrinsic apoptotic pathway by downregulating PUMA. These findings further support the clinical relevance of platelets and PMPs in AML.