Dating of mortar and bricks from the Castle of Kastelholm

In connection with the excavation and restauration works at Kastelholm radiocarbon dating of mortar from the walls of the castle has been attempted. Except for a date clearly affected by old carbonate and a few samples of modern age, the calibrated samples date back to the 14th century. Four bricks from different parts of the tower of the castle dated by the thermoluminescence method gave ages between 1490 and 1600 AD. The TL measurements are made on feldspar inclusions extracted from the bricks. The dating results are in agreement with those from the archaeological investigations

First direct dating of Late Pleistocene ice-wedges by AMS

We present the first direct dating by C-14-accelerator mass spectrometry of three Late Pleistocene syngenetic ice-wedges from the Seyaha cross-section. They are representative of permafrost with multistage ice-wedges from the North of Western Siberia. The most important result is the clear vertical age stratification of the ice, i.e. the old ice is located beneath the young. This shows that a timescale can be assigned to these ice-wedges penetrating down into the permafrost. The age of the ice shows a depth of not more than 3-5 m for frost cracking; water penetrated into the ice-wedges at that depth. The lower part of the ice-wedges from the Seyaha cross-section has been dated between 21 000 and 14 000 BP. (C) 2000 Elsevier Science B.V. All rights reserved

Serum Calcium and the Risk of Breast Cancer: Findings from the Swedish AMORIS Study and a Meta-Analysis of Prospective Studies

To investigate the association between serum calcium and risk of breast cancer using a large cohort and a systematic review with meta-analysis. From the Swedish Apolipoprotein Mortality Risk (AMORIS) Study we included 229,674 women who had baseline measurements of serum total calcium and albumin. Multivariable Cox regression was used to assess the association between total and albumin-corrected calcium and breast cancer risk. For the systematic review, an electronic search of MEDLINE and EMBASE databases was performed to identify other prospective cohorts assessing the relationship between serum calcium and breast cancer risk. We pooled the results of our AMORIS cohort with other eligible studies in a meta-analysis using a random effects model. I² test was used to assess heterogeneity. In the AMORIS study, 10,863 women were diagnosed with breast cancer (mean follow-up: 19 years). We found an inverse association between total serum calcium and breast cancer when comparing the fourth quartile to the first quartile (HR: 0.94, 95% CI: 0.88-0.99, p value for trend 0.04) and similar results using albumin-corrected calcium. In the systematic review, we identified another two prospective cohorts evaluating pre-diagnostic serum total calcium and breast cancer. Combining these studies and our findings in AMORIS in a meta-analysis showed a protective effect of serum calcium against breast cancer, with a summary RR of 0.80 (95% CI: 0.66-0.97). No substantial heterogeneity was observed. Our findings in AMORIS and the meta-analysis support an inverse association between serum calcium and breast cancer risk, which warrants mechanistic investigations

Global Solar Variations and Effects of Relativistic 2D-Hydrogen

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