Incubation of (3S)-3-fluoro-3-deoxy-D-arabino-heptulosonate 7-phosphate with dehydroquinate (DHQ) synthase from three phylogenetically distinct sources resulted in the production of (6S)-6-fluoroDHQ and its epimer 1-epi-(6S)-6-fluoroDHQ. The differences in the product ratios of the reactions catalysed by each enzyme imply that 1-epi-(6S)-6-fluoroDHQ formation occurs by an unusual partial leakag...

Water vapor content in the atmosphere is very significant for atmospheric correction of optical remote sensing data. Nowadays, the common atmospheric correction models use a single value of the average water vapor content of the study area to perform atmospheric correction. As the distribution of water vapor content varies greatly with time and space, it is obviously inaccurate to represent the...

The enantioselective syntheses of two stereoisomers, (2R,6S,10S) and (2S,6S,10S), of methyl 2,6,10-trimethyldodecanote, out of eight possible isomers, are described , employing the stereoselective hydroboration of (-)-isopulegol (2) and (+)-neo-isopulegol (2a) as the key reaction.

Radiative Transfer Models (RTMs) are widely used to simulate the passage of solar radiation through atmospheres on Earth and other planets. They have a range of uses including atmospheric research and solar energy system design, and are widely used within remote sensing and Earth observation, but they are often seen as difficult to use with respect to the numerous input and outputs parameters. ...

A collaborative peer network application called 6Search (6S) is proposed to address the scalability limitations of centralized search engines. 6S peers depend on a local adaptive routing algorithm to dynamically change the topology of the peer network and search for the best neighbors to answer their queries. We validate prototypes of the 6S network via simulations with 70− 500 model users base...

Coxiella burnetii, an obligate intracellular bacterial pathogen that causes Q fever, undergoes a biphasic developmental cycle that alternates between a metabolically-active large cell variant (LCV) and a dormant small cell variant (SCV). As such, the bacterium undoubtedly employs complex modes of regulating its lifecycle, metabolism and pathogenesis. Small RNAs (sRNAs) have been shown to play i...

Heparanase is an endo-beta-D-glucuronidase that cleaves the heparan sulfate chains of heparan sulfate proteoglycans and is implicated in angiogenesis and metastasis. With the aim of establishing a simple and reliable method for studying the susceptibility of heparin/heparan sulfate oligosaccharides to be cleaved by heparanase, an on-line ion pair reversed-phase high-performance liquid chromatog...

6S RNA is a noncoding RNA that inhibits bacterial transcription by sequestering RNA polymerase holoenzyme (Eσ(70)) in low-nutrient conditions. This transcriptional block can be relieved by the synthesis of a short product RNA (pRNA) using the 6S RNA as a template. Here, we selected a range of 6S RNA release-defective mutants from a high diversity in vitro pool. Studying the release-defective va...

The 6S RNA in Escherichia coli suppresses housekeeping transcription by binding to RNA polymerase holoenzyme (core polymerase + s) under low nutrient conditions and rescues s-dependent transcription in high nutrient conditions by the synthesis of a short product RNA (pRNA) using itself as a template. Here we characterize a kinetic intermediate that arises during 6S RNA release. This state, cons...

We present a lifetime measurements of the 6s level of rubidium. We use a time-correlated singlephoton counting technique on two different samples of rubidium atoms. A vapor cell with variable rubidium density and a sample of atoms confined and cooled in a magneto-optical trap. The 5P1/2 level serves as the resonant intermediate step for the two step excitation to the 6s level. We detect the dec...