LOFAR, the LOw-Frequency ARray, is a new-generation radio interferometer constructed in the north of the Netherlands and across europe. Utilizing a novel phased-array design, LOFAR covers the... Show moreLOFAR, the LOw-Frequency ARray, is a new-generation radio interferometer constructed in the north of the Netherlands and across europe. Utilizing a novel phased-array design, LOFAR covers the largely unexplored low-frequency range from 10-240 MHz and provides a number of unique observing capabilities. Spreading out from a core located near the village of Exloo in the northeast of the Netherlands, a total of 40 LOFAR stations are nearing completion. A further five stations have been deployed throughout Germany, and one station has been built in each of France, Sweden, and the UK. Digital beam-forming techniques make the LOFAR system agile and allow for rapid repointing of the telescope as well as the potential for multiple simultaneous observations. With its dense core array and long interferometric baselines, LOFAR achieves unparalleled sensitivity and angular resolution in the low-frequency radio regime. The LOFAR facilities are jointly operated by the International LOFAR Telescope (ILT) foundation, as an observatory open to the global astronomical community. LOFAR is one of the first radio observatories to feature automated processing pipelines to deliver fully calibrated science products to its user community. LOFAR's new capabilities, techniques and modus operandi make it an important pathfinder for the Square Kilometre Array (SKA). We give an overview of the LOFAR instrument, its major hardware and software components, and the core science objectives that have driven its design. In addition, we present a selection of new results from the commissioning phase of this new radio observatory. Show less
Andersen, S.D.; Liberti, S.E.; Lutzen, A.; Drost, M.; Bernstein, I.; Nilbert, M.; ... ; Rasmussen, L.J. 2012
The hereditary colon and endometrium cancer predisposition Lynch Syndrome (also called HNPCC) is caused by a germ-line mutation in one of the DNA mismatch repair (MMR) genes. A significant fraction... Show moreThe hereditary colon and endometrium cancer predisposition Lynch Syndrome (also called HNPCC) is caused by a germ-line mutation in one of the DNA mismatch repair (MMR) genes. A significant fraction of the gene alterations detected in suspected Lynch Syndrome patients is comprised of amino acid substitutions. The relevance for cancer risk of these variants is difficult to assess, as currently no time- and cost-effective, validated, and widely applicable functional assays for the measurement of MMR activity are available. Here we describe a rapid, cell-free, and easily quantifiable MMR activity assay for the diagnostic assessment of variants of the MLH1 MMR protein. This assay allows the parallel generation and functional analysis of a series of variants of the MLH1 protein in vitro using readily available, or preprepared, reagents. Using this assay we have tested 26 MLH1 variants and of these, 15 had lost activity. These results are in concordance with those obtained from first-generation assays and with in silico and pathology data. After its multifocal technical and clinical validation this assay could have great impact for the diagnosis and counseling of carriers of an MLH1 variant and their relatives. Show less