<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kaelin M. Cawley</style></author><author><style face="normal" font="default" size="100%">Diane M. McKnight</style></author><author><style face="normal" font="default" size="100%">Penney L. Miller</style></author><author><style face="normal" font="default" size="100%">Rose M. Cory</style></author><author><style face="normal" font="default" size="100%">Fimmen, Ryan L</style></author><author><style face="normal" font="default" size="100%">Guerard, Jennifer</style></author><author><style face="normal" font="default" size="100%">Markus Dieser</style></author><author><style face="normal" font="default" size="100%">Chris Jaros</style></author><author><style face="normal" font="default" size="100%">Yu-Ping Chin</style></author><author><style face="normal" font="default" size="100%">Christine M. Foreman</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Characterization of fulvic acid fractions of dissolved organic matter during ice-out in a hyper-eutrophic, coastal pond in Antarctica</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental Research Letters</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2013</style></year><pub-dates><date><style  face="normal" font="default" size="100%">12/2013</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">8</style></volume><pages><style face="normal" font="default" size="100%">045015</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Dissolved humic material (HDOM) is ubiquitous to all natural waters and its source material influences its chemical structure, reactivity, and bioavailability. While terrestrially derived HDOM reference materials distributed by the International Humic Substances Society (IHSS) have been readily available to engineering and scientific communities, a microbially derived reference HDOM was not, despite the well-characterized differences in the chemistry and reactivity of HDOM derived from terrestrial versus microbial sources. To address this gap, we collected a microbial reference fulvic acid from Pony Lake (PLFA) for distribution through the IHSS. Pony Lake is a saline coastal pond on Ross Island, Antarctica, where the landscape is devoid of terrestrial plants. Sample collection occurred over a 17-day period in the summer season at Pony Lake. During this time, the dissolved organic carbon (DOC) concentrations increased nearly two-fold, and the fulvic acid fraction (collected using the XAD-8 method) accounted for 14.6% of the DOC. During the re-concentration and desalting procedures we isolated two other chemically distinct fulvic acid fractions: (1) PLFA-2, which was high in carbohydrates and (2) PLFA-CER, which was high in nitrogen. The chemical characteristics (elemental analysis, optical characterization with UV–vis and fluorescence spectroscopy, and 13C NMR spectroscopy) of the three fulvic acid fractions helped to explain their behavior during isolation.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Markus Dieser</style></author><author><style face="normal" font="default" size="100%">Christine M. Foreman</style></author><author><style face="normal" font="default" size="100%">Chris Jaros</style></author><author><style face="normal" font="default" size="100%">John T. Lisle</style></author><author><style face="normal" font="default" size="100%">Mark C. Greenwood</style></author><author><style face="normal" font="default" size="100%">Johanna Laybourn-Parry</style></author><author><style face="normal" font="default" size="100%">Penney L. Miller</style></author><author><style face="normal" font="default" size="100%">Yu-Ping Chin</style></author><author><style face="normal" font="default" size="100%">Diane M. McKnight</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Physicochemical and biological dynamics in a coastal Antarctic lake as it transitions from frozen to open water</style></title><secondary-title><style face="normal" font="default" size="100%">Antarctic Science</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2013</style></year><pub-dates><date><style  face="normal" font="default" size="100%">12/2013</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">25</style></volume><pages><style face="normal" font="default" size="100%">663–675</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><issue><style face="normal" font="default" size="100%">5</style></issue></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Christine M. Foreman</style></author><author><style face="normal" font="default" size="100%">Markus Dieser</style></author><author><style face="normal" font="default" size="100%">Mark Greenwood</style></author><author><style face="normal" font="default" size="100%">Rose M. Cory</style></author><author><style face="normal" font="default" size="100%">Johanna Laybourn-Parry</style></author><author><style face="normal" font="default" size="100%">John T. Lisle</style></author><author><style face="normal" font="default" size="100%">Chris Jaros</style></author><author><style face="normal" font="default" size="100%">Penney L. Miller</style></author><author><style face="normal" font="default" size="100%">Yu-Ping Chin</style></author><author><style face="normal" font="default" size="100%">Diane M. McKnight</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">When a habitat freezes solid: microorganisms over-winter within the ice column of a coastal Antarctic lake</style></title><secondary-title><style face="normal" font="default" size="100%">FEMS Microbiology Ecology</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2011</style></year><pub-dates><date><style  face="normal" font="default" size="100%">06/2011</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://onlinelibrary.wiley.com/doi/10.1111/j.1574-6941.2011.01061.x/full</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">76</style></volume><pages><style face="normal" font="default" size="100%">401 - 412</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><issue><style face="normal" font="default" size="100%">3</style></issue></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Markus Dieser</style></author><author><style face="normal" font="default" size="100%">Nocker, Andreas</style></author><author><style face="normal" font="default" size="100%">John C. Priscu</style></author><author><style face="normal" font="default" size="100%">Christine M. Foreman</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Viable microbes in ice: application of molecular assays to McMurdo Dry Valley lake ice communities</style></title><secondary-title><style face="normal" font="default" size="100%">Antarctic Science</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2010</style></year><pub-dates><date><style  face="normal" font="default" size="100%">10/2010</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://journals.cambridge.org/action/displayAbstract?fromPage=online&amp;aid=7909836&amp;fileId=S0954102010000404</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">22</style></volume><pages><style face="normal" font="default" size="100%">470 - 476</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;The permanent ice covers of the McMurdo Dry Valley lakes, Antarctica, are colonized by a diverse microbial assemblage. We collected ice cores from Lakes Fryxell, Hoare and Bonney. Propidium monoazide (PMA) was used in combination with quantitative PCR (qPCR) and denaturing gradient gel electrophoresis (DGGE) to examine membrane integrity of prokaryotes in these extreme environments. PMA selectively penetrates cells with compromised membranes and modifies their DNA resulting in the suppression of PCR amplification. Our results based on analysis of 16S rRNA genes demonstrate that despite the hostile conditions of the Dry Valleys, the permanent ice covers of the lakes support a &amp;lsquo;potentially viable&amp;rsquo; microbial community. The level of membrane integrity, as well as diversity, was higher in samples where sediment was entrapped in the ice cover. Pronounced differences in the fraction of cells with intact and compromised cell membranes were found for Lake Fryxell and east lobe of Lake Bonney, both expressed in differences in DGGE banding patterns and qPCR signal reductions. Limitations in the ability to distinguish between intact or compromised cells occurred in samples from Lake Hoare and west lobe of Lake Bonney due to low DNA template concentrations recovered from the samples.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">05</style></issue></record></records></xml>