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The Surface Ocean CO2 Atlas (SOCAT) is a synthesis of quality-controlled fCO2 (fugacity of carbon dioxide) values for the global surface oceans and coastal seas with regular updates. Version 3 of SOCAT has 14.5 million fCO2 values from 3646 data sets covering the years 1957 to 2014. This latest version has an additional 4.4 million fCO2 values relative to version 2 and extends the record from 2011 to 2014. Version 3 also significantly increases the data availability for 2005 to 2013. SOCAT has an average of approximately 1.2 million surface water fCO2 values per year for the years 2006 to 2012. Quality and documentation of the data has improved. A new feature is the data set quality control (QC) flag of E for data from alternative sensors and platforms. The accuracy of surface water fCO2 has been defined for all data set QC flags. Automated range checking has been carried out for all data sets during their upload into SOCAT. The upgrade of the interactive Data Set Viewer (previously known as the Cruise Data Viewer) allows better interrogation of the SOCAT data collection and rapid creation of high-quality figures for scientific presentations. Automated data upload has been launched for version 4 and will enable more frequent SOCAT releases in the future. High-profile scientific applications of SOCAT include quantification of the ocean sink for atmospheric carbon dioxide and its long-term variation, detection of ocean acidification, as well as evaluation of coupled-climate and ocean-only biogeochemical models. Users of SOCAT data products are urged to acknowledge the contribution of data providers, as stated in the SOCAT Fair Data Use Statement. This ESSD (Earth System Science Data) "Living Data" publication documents the methods and data sets used for the assembly of this new version of the SOCAT data collection and compares these with those used for earlier versions of the data collection (Pfeil et al., 2013; Sabine et al., 2013; Bakker et al., 2014).

The electric field of a laser pulse exerts a force on charged particles which can be on the order of (or exceed) the forces that bind electrons to atoms, molecules, solids or that bind atoms together in molecules or solids. With modern laser technology, this force can be applied with almost 1 fs, 1 µm precision. Even if the field is lower than the field required to ionize atoms or molecules, large nonresonant Stark shifts can be achieved. The Stark shift gives us a means to control molecules. The dependence of the Stark shift with respect to the intensity profile of the laser focus determines the spatial force exerted on the molecule. The dependence of the Stark shift on the orientation of the molecule with respect to the laser polarization determines the torque exerted on the molecule. Through these forces we can control position, orientation, and linear and/or angular velocity. The Stark shift also depends on the internuclear co-ordinates, giving us some degree of control over the structure of the potential energy surface in molecules. The ability to control these basic forces with precision depends on our ability to control optical pulses. Progress towards producing high power pulses with almost arbitrary time-dependent infrared fields will be discussed. In even stronger fields, where ionization occurs, the shifting and mixing of states becomes extreme. Measurement in this complex spectroscopic environment is difficult. Intuition based on perturbation theory is of limited value. Yet strong field probing allows us to supply a lot of electronic energy to a molecule very rapidly and to localize measurements in space and time. We illustrate molecular alignment and strong field probing together in one experiment where we study femtosecond dissociative ionization.

The transcriptional induction of the GAL genes of Saccharomyces cerevisiae occurs when galactose and ATP interact with Gal3p. This protein-small molecule complex associates with Gal80p to relieve its inhibitory effect on the transcriptional activator Gal4p. Gal3p shares a high degree of sequence homology to galactokinase, Gal1p, but does not itself possess galactokinase activity. By constructing chimeric proteins in which regions of the GAL1 gene are inserted into the GAL3 coding sequence, we have been able to impart galactokinase activity upon Gal3p as judged in vivo and in vitro . Remarkably, the insertion of just two amino acids from Gal1p into the corresponding region of Gal3p confers galactokinase activity onto the resultant protein. The chimeric protein, termed Gal3p+SA, retains its ability to efficiently induce the GAL genes. Kinetic analysis of Gal3p+SA reveals that the K m for galactose is similar to that of Gal1p, but the K m for ATP is increased. The chimeric enzyme was found to have a decreased turnover number in comparison to Gal1p. These results are discussed in terms of both the mechanism of galactokinase function and that of transcriptional induction.