Photodegradation of dissolved organic matter (DOM) is highly important in humic waters of peatland regions, yet the coupling between organic and organo-mineral colloids, trace metals and bioavailability of photodegraded products is poorly known. Here we studied photo-destruction of organo-mineral colloids induced by UV-irradiation of sterile-filtered mire water. We revealed two simultaneously occurring processes of transformation of DOM and trace elements speciation: (i) disintegration of high molecular weight organo-mineral colloids into lower molecular weight (<1 kDa) DOM and metal complexes and (ii) formation of particulate (>0.
View Article and Find Full Text PDFObjective: Minimally invasive multivessel coronary artery bypass grafting (MIM CABG) has demonstrated its safety, effectiveness and high rate of reproducibility. However, minithoracotomy CABG is still rarely performed. In this study, we retrospectively analyze the CT-angiographic graft patency rates for the patients subjected to this operation.
View Article and Find Full Text PDFBiodegradation and photolysis of dissolved organic matter (DOM) in boreal high-latitude waters are the two main factors controlling not only the aquatic fluxes and residence time of carbon but also metal nutrients associated with DOM such as Fe. The DOM is usually present in the form of organic and organomineral colloids, which also account for the majority of dissolved Fe. Here, we use the stable Fe isotope approach to unravel the processes controlling Fe behavior during bio- and photodegradation of colloids in boreal Fe- and DOM-rich humic waters (a stream and a fen).
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