PubMed · 11813395
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J Hamilton. 2001. USC moves to problem-based learning.. https://pubmed.ncbi.nlm.nih.gov/11813395/
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In this study, we report the coding-complete genome sequence of Grapevine leafroll-associated virus 13 (GLRaV-13), isolate CA8881, detected in Vitis vinifera in California, USA. The genome sequence exhibited over 95% nucleotide identity with previously reported GLRaV-13 isolates and contributed to better understanding of the genetic diversity of ampeloviruses infecting grapevine.
The concentration of fecal indicator bacteria in the surf zone at Huntington Beach, CA, varies over time scales that span at least 7 orders of magnitude, from minutes to decades. Sources of this variability include historical changes in the treatment and disposal of wastewater and dry weather runoff, El Niño events, seasonal variations in rainfall, spring-neap tidal cycles, sunlight-induced mortality of bacteria, and nearshore mixing. On average, total coliform concentrations have decreased over the past 43 years, although point sources of shoreline contamination (storm drains, river outlets, and submarine outfalls) continue to cause transiently poor water quality. These transient point sources typically persist for 5-8 yr and are modulated by the phase of the moon, reflecting the influence of tides on the sourcing and transport of pollutants in the coastal ocean. Indicator bacteria are very sensitive to sunlight therefore, the time of day when samples are collected can influence the outcome of water quality testing. These results demonstrate that coastal water quality is forced by a complex combination of local and external processes and raise questions about the efficacy of existing marine bathing water monitoring and reporting programs.
An overview of methyl tert-butyl ether (MTBE) concentrations in German river water (315 samples) and wastewater (82 samples) is given. In the agglomerated area of Frankfurt/M, several samples of surface water, wastewater, and industrial effluents were analyzed for its MTBE content from 1999 to 2001. MTBE was analyzed by a combination of headspace-solid-phase microextraction and gas chromatography-mass spectrometry (HS-SPME/GC-MS). Rhine and Main water concentrations of MTBE in the lower parts of the rivers were approximately 250 ng/L and 200 ng/L, respectively. The concentrations increased from the upper parts of the rivers to its mouths. Water from the Elbe, Neckar, and Weser rivers showed lower MTBE concentrations, and the ether was not detected in the Danube river. Generally, higher MTBE concentrations were detected at urban agglomerations compared to rural areas. Small urban creeks without significant industrial input showed MTBE concentrations of approximately 50 ng/L, and it was hardly detectable in small rural creeks. Higher MTBE concentrations in river water were correlated with increased concentrations of the oxygenate measured in precipitation. Most MTBE concentrations in river water fell in the range of 50-200 ng/L (32%), 10-50 ng/L (28%), and 200-1000 ng/L (26%). MTBE concentrations in German surface water and air are 3-17 times lower compared to Californian data. Wastewater samples from influents of two sewage plants showed MTBE concentrations of approximately 100-300 ng/L, and a loading of 2-37 kg/a was calculated. An eliminated MTBE percentage of roughly 30-35% of MTBE in the plants was estimated. Industrially influenced samples of river water or public wastewater and industrial effluents showed MTBE concentrations of up to 2267 ng/L and 28 microg/L, respectively. This input has not been considered before because only 1.5% of the produced amount of MTBE in Germany is used for industrial processes, but it should not be neglected because MTBE is very persistent in water.