Aircraft observations have revealed ubiquitous new particle formation in the tropical upper troposphere over the Amazon and the Atlantic and Pacific oceans. Although the vapours involved remain unknown, recent satellite observations have revealed surprisingly high night-time isoprene mixing ratios of up to 1 part per billion by volume (ppbv) in the tropical upper troposphere. Here, in experiments performed with the CERN CLOUD (Cosmics Leaving Outdoor Droplets) chamber, we report new particle formation initiated by the reaction of hydroxyl radicals with isoprene at upper-tropospheric temperatures of -30 °C and -50 °C.
View Article and Find Full Text PDFMass spectrometry is uniquely suited to identify and quantify environmentally relevant molecules and molecular clusters. Mass spectrometry alone is, however, not able to distinguish between isomers. In this study, we demonstrate the use of both an experimental set-up using a differential mobility analyser, and computational ion mobility calculations for identification of isomers.
View Article and Find Full Text PDFBackground: Most patients with unrepaired coarctation of the aorta die before the age of 50 years. In patients who present at an older age, the indications for surgical treatment are controversial because the benefits of operating are unclear.
Methods: At follow-up investigation from 0.
History And Findings: A 33-year-old man was admitted 7 years after a testicular teratomatous carcinoma had first been diagnosed, treated by a right orchiectomy and two-stage radical retroperitoneal lymphadenectomy. Five years later the first mediastinal metastases were treated with high-dosage chemotherapy and autologous germ-cell transplantation, and remaining paraaortic--mediastinal tumour tissue was resected. Two years later another tumour at that site was only partially resected.
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