We will begin by defining some logical connectives. The first logical connective is implication. Luckily, implication is already built in to the Haskell type system in the form of arrow types. The type p -> q is equivalent to the logical statement P → Q. We can now prove a very simple theorem called Modus Ponens. Modus Ponens states that if P implies Q and P is true, then Q is true. It is often...

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Shewanella loihica strain PV-4 harbors both a functional denitrification (NO3 (-)→N2) and a respiratory ammonification (NO3 (-)→NH4 (+)) pathway. Batch and chemostat experiments revealed that NO2 (-) affects pathway selection and the formation of reduced products. Strain PV-4 cells grown with NO2 (-) as the sole electron acceptor produced exclusively NH4 (+). With NO3 (-) as the electron accept...

[1] We present an approach to infer ground-level nitrogen dioxide (NO2) concentrations by applying local scaling factors from a global three-dimensional model (GEOS-Chem) to tropospheric NO2 columns retrieved from the Ozone Monitoring Instrument (OMI) onboard the Aura satellite. Seasonal mean OMI surface NO2 derived from the standard tropospheric NO2 data product (Version 1.0.5, Collection 3) v...

194 JADA, Vol. 135, February 2004 R E S E A R C H Background. Light-activated bleaching is a method of tooth whitening. The authors conducted a study to compare the whitening effects and tooth temperature changes induced by various combinations of peroxide bleaches and light sources. Methods. The authors randomly assigned 250 extracted human teeth halves into experimental groups (n = 10). A pla...

194 NATURE | VOL 410 | 8 MARCH 2001 | www.nature.com ture. The integrated PL also increases with temperature in the same manner as the EL, indicating that the temperature dependence is intrinsic to the recombination, rather than the injection mechanism. The strong temperature quenching of PL and EL in most semiconductors is primarily the result of the strong temperature dependence of the compet...

Colorectal cancer (CRC) is a major cause of premature death in the UK and many developed countries. However, the risk of developing CRC is well recognised to be associated not only with diet but also with obesity and lack of exercise. While epidemiological evidence shows an association with factors such as high red meat intake and low intake of vegetables, fibre and fish, the mechanisms underly...

We investigate the effects of aerosol optical depth (AOD), single scattering albedo (SSA), aerosol peak height (APH), measurement geometry (solar zenith angle (SZA) and viewing zenith angle (VZA)), relative azimuth angle, and surface reflectance on the accuracy of NO2 slant column density using synthetic radiance. High AOD and APH are found to decrease NO2 SCD retrieval accuracy. In moderately ...

Surface NO2 volume mixing ratio (VMR) at a specific time (13:45 Local time) (NO2 VMRST) and monthly mean surface NO2 VMR (NO2 VMRM) are estimated for the first time using three regression models with Ozone Monitoring Instrument (OMI) data in four metropolitan cities in South Korea: Seoul, Gyeonggi, Daejeon, and Gwangju. Relationships between the surface NO2 VMR obtained from in situ measurement...

Nitric oxide (NO) in oxygen-containing aqueous solution has a short half-life that is often attributed to a rapid oxidation to both NO2- and NO3-. The chemical fate of NO in aqueous solution is often assumed to be the same as that in air, where NO is oxidized to NO2 followed by dimerization to N2O4. Water then reacts with N2O4 to form both NO2- and NO3-. We report here that NO in aqueous soluti...