Measurement and modeling of multiple substrate oxidation by methanotrophs at 20 °C

Earlier experiments have shown that when Methylosinus trichosporium OB3b was grown at 30 °C, greater growth and degradation of chlorinated ethenes was observed under particulate methane monooxygenase (pMMO)-expressing conditions than sMMO-expressing conditions. The effect of temperature on the growth and ability of methanotrophs to degrade chlorinated ethenes, however, has not been examined, particularly temperatures more representative of groundwater systems. Thus, experiments were performed at 20 °C to examine the effect of mixtures of trichloroethylene, trans -dichloroethylene and vinyl chloride in the presence of methane on the growth and ability of Methylosinus trichosporium OB3b cells to degrade these pollutants. Although the maximal rates of chlorinated ethane degradation were greater by M. trichosporium OB3b expressing sMMO as compared with the same cell expressing pMMO, the growth and ability of sMMO-expressing cells to degrade these cosubstrates was substantially inhibited in their presence as compared with the same cell expressing pMMO. The Δ model developed earlier was found to be useful for predicting the effect of chlorinated ethenes on the growth and ability of M. trichosporium OB3b to degrade these compounds at a growth temperature of 20 °C. Finally, it was also discovered that at 20 °C, cells expressing pMMO exhibited faster turnover of methane than sMMO-expressing cells, unlike that found earlier at 30 °C, suggesting that temperature may exert selective pressure on methanotrophic communities to express sMMO or pMMO.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75464/1/j.1574-6968.2008.01314.x.pd

Assessing The Health Of Fringing Salt Marshes Along The Fore River And Its Tributaries

Casco Bay has experienced two significant oil spills in recent history - the Tamano Tanker spill in 1972 and the Julie N spill in 1996. In addition, the Fore River and its tributaries have experienced numerous small spills over the years, including the August 2002 fuel oil spill (2,900 gallons) and the April 2003 jet fuel spill (6,000 gallons). The impacts of these spills on the fringing salt marshes that line the edges of the Fore River and its tributaries are not well understood. Are these salt marshes resilient enough to withstand these impacts and still act as healthy marshes should? Or are they functioning at lower levels, compared to other fringing salt marshes in Casco Bay? The salt marshes that line the Fore River provide an important suite of functions and values to the citizens of southern Maine. The results of this study will help resource managers in their efforts to protect these important and unique natural resources

A Comprehensive Wetland Program For Fringing Salt Marshes In The York River, Maine

The overall goal of this project was to assist the Town of York, Maine, in its efforts to monitor and protect the fringing salt marshes along the York River. In particular, the project focused on potential impacts to the marshes due to shoreline development pressures. Specific objectives included (1) gathering baseline data about the marshes (2) developing a set of indicators to be used in future monitoring, and (3) generating management recommendations

Measuring Entangled Qutrits and Their Use for Quantum Bit Commitment

We produce and holographically measure entangled qudits encoded in transverse spatial modes of single photons. With the novel use of a quantum state tomography method that only requires two-state superpositions, we achieve the most complete characterisation of entangled qutrits to date. Ideally, entangled qutrits provide better security than qubits in quantum bit-commitment: we model the sensitivity of this to mixture and show experimentally and theoretically that qutrits with even a small amount of decoherence cannot offer increased security over qubits.Comment: Paper updated to match published version; 5 pages, 4 figures, images have been included at slightly lower quality for the archiv

Tigard Walks (A Plan for Walkable Neighborhoods in Tigard)

The Walkable Neighborhoods Plan for Tigard outlines a set of strategies to help Tigard’s residents, businesses, and leaders build their city into a more walkable place. These five strategies are based on three core values gleaned from StepUP Studio’s outreach efforts to the people living and working in and for the city of Tigard. This project was conducted under the supervision of Sy Adler, Marisa A. Zapata and Gil Kelle