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BACKGROUND Polyhydroxyalkanoates (PHAs) can be degraded by many microorganisms using intra- or extracellular PHA depolymerases. PHA depolymerases are very diverse in sequence and substrate specificity, but share a common alpha/beta-hydrolase fold and a catalytic triad, which is also found in other alpha/beta-hydrolases. RESULTS The PHA Depolymerase(More)
To obtain the highest-resolution ray-based tomographic images from crosshole ground-penetrating radar ͑GPR͒ data, wide angular ray coverage of the region between the two boreholes is required. Unfortunately, at borehole spacings on the order of a few meters, high-angle traveltime data ͑i.e., traveltime data corresponding to transmitter-receiver angles(More)
Traveltimes of direct arrivals in vertical radar profiles ͑VRPs͒ are tomographically inverted to estimate the earth's electromagnetic ͑EM͒ velocity between a surface transmitter and a downhole receiver. We determine the 1D interval velocity model that best fits the first-arrival traveltimes by using a weighted, damped, least-squares inversion scheme. We(More)
In this study, we investigate the use of crosswell P-wave seismic tomography to obtain spatially extensive information about subsurface sedimentary architecture and hetero-geneity in alluvial aquifers. Our field site was a research wellfield in an unconfined aquifer near Boise, Idaho. The aquifer consists of a ϳ 20-m-thick sequence of alluvial cobble and(More)
—This paper presents a high-performance maximum power point tracker (MPPT) optimized for fast cloudy conditions, e.g., rapidly changing irradiation on the photovoltaic panels. The rapidly changing conditions are tracked by an optimized hill– climbing MPPT method called dP-P&O. This algorithm separates the effects of the irradiation change from the effect of(More)
SUMMARY The Cytochrome P450 Engineering Database (CYPED) has been designed to serve as a tool for a comprehensive and systematic comparison of protein sequences and structures within the vast and diverse family of cytochrome P450 monooxygenases (CYPs). The CYPED currently integrates sequence and structure data of 3911 and 25 proteins, respectively. Proteins(More)
Major horizons in radar reflection profiles may correlate with contacts between stratigraphic units or with structural breaks such as fault surfaces. Minor reflections may be caused by clutter or, in some cases, may indicate material properties or structure within stratigraphic units. In this study, we examine the physical basis for major and minor(More)
Georadar attenuation-difference tomography is a useful tool for imaging temporal and spatial changes in bulk electrical conductivity due to fluid flow and other subsurface processes. The most common method of attenuation-difference tomography employs the ray approximation where waves are assumed to propagate at infinite frequency. Ray approximation causes(More)
We tested a prototype capacitive-conductivity borehole tool in a shallow, unconfined aquifer with coarse, unconsoli-dated sediments and very-low-conductivity water at the Boi-se Hydrogeophysical Research Site ͑BHRS͒. Examining such a high-resistivity system provides a good test for the ca-pacitive-conductivity tool because the conventional induction(More)
Limitations of imaging using electrical resistivity tomography (ERT) arise because of the difficulty of quantifying the reliability of tomographic images. A major source of uncertainty in tomographic inversion is data error. Data error due to electrode mislocations is characterized by the sensitivity of electrical potential to both source and receiver(More)