The structure of NMB1585, a MarR-family regulator from Neisseria meningitidis

The structure of the MarR-family regulator NMB1585 from N. meningitidis has been solved using data extending to 2.1 Å resolution

Crystal structure of nitrogen regulatory protein IIA(Ntr )from Neisseria meningitidis

BACKGROUND: The NMB0736 gene of Neisseria meningitidis serogroup B strain MC58 encodes the putative nitrogen regulatory protein, IIA(Ntr )(abbreviated to NM-IIA(Ntr)). The homologous protein present in Escherichia coli is implicated in the control of nitrogen assimilation. As part of a structural proteomics approach to the study of pathogenic Neisseria spp., we have selected this protein for structure determination by X-ray crystallography. RESULTS: The NM-IIA(Ntr )was over-expressed in E. coli and was shown to be partially mono-phosphorylated, as assessed by mass spectrometry of the purified protein. Crystals of un-phosphorylated protein were obtained and diffraction data collected to 2.5 Å resolution. The structure of NM-IIA(Ntr )was solved by molecular replacement using the coordinates of the E. coli nitrogen regulatory protein IIA(ntr )[PDB: 1A6J] as the starting model. The overall fold of the Neisseria enzyme shows a high degree of similarity to the IIA(Ntr )from E. coli, and the position of the phosphoryl acceptor histidine residue (H67) is conserved. The orientation of an adjacent arginine residue (R69) suggests that it may also be involved in coordinating the phosphate group. Comparison of the structure with that of E. coli IIA(mtl )complexed with HPr [PDB: 1J6T] indicates that NM-IIA(Ntr )binds in a similar way to the HPr-like enzyme in Neisseria. CONCLUSION: The structure of NM-IIA(Ntr )confirms its assignment as a homologue of the IIA(Ntr )proteins found in a range of other Gram-negative bacteria. We conclude that the NM- IIA(Ntr )protein functions as part of a phosphorylation cascade which, in contrast to E. coli, shares the upstream phosphotransfer protein with the sugar uptake phosphoenolpyruvate:sugar phosphotransferase system (PTS), but in common with E. coli has a distinct downstream effector mechanism

Mesozoic climates and oceans – a tribute to Hugh Jenkyns and Helmut Weissert

This is the author accepted manuscript. The final version is available from Wiley via the DOI in this record.The study of past greenhouse climate intervals in Earth history, such as the Mesozoic, is an important, relevant and dynamic area of research for many sedimentary geologists, geochemists, palaeontologists and climate modellers. The Mesozoic sedimentary record provides key insights into the mechanics of how the Earth system works under warmer conditions, providing examples of natural climate change and perturbations to ocean chemistry, including anoxia, that are of societal relevance for understanding and contextualizing ongoing and future environmental problems. Furthermore, the deposition of widespread organic-carbon-rich sediments (‘black shales’) during the Mesozoic means that this is an era of considerable economic interest. In July 2015, an international group of geoscientists attended a workshop in Ascona, Switzerland, to discuss all aspects of the Mesozoic world and to celebrate the four-decade-long contributions made by Hugh Jenkyns (University of Oxford) and Helmut Weissert (ETH Zürich) to our understanding of this fascinating era in Earth history. This volume of Sedimentology arose from that meeting and contains papers inspired by (and co-authored by!) Hugh and Helmi. Here, a brief introduction to the volume is provided that reviews aspects of Hugh and Helmi's major achievements; contextualizes the papers of the Thematic Issue; and discusses some of the outstanding questions and areas for future research

Reducing car-use for leisure: can organised walking groups switch from car travel to bus and train walks?

This paper deals with the significant leisure travel sector, focusing on the attitudes of organised walking groups towards public transport use. A series of interviews with walking group leaders explored the design of organised walks, and factors affecting journeys to and from start points. The themes presented suggest an overlying group culture involving mainly circular walks, reached by car. The research indicates an underlying engrained dependency on cars to reach walks and a degree of opposition to using public transport, which generally contradicts widely–held attitudes towards protecting the environment. Future research should focus more in depth on the long-term removal of psychological barriers to using public transport for leisure, and persuasive measures aimed at groups

Origins of the Ambient Solar Wind: Implications for Space Weather

The Sun's outer atmosphere is heated to temperatures of millions of degrees, and solar plasma flows out into interplanetary space at supersonic speeds. This paper reviews our current understanding of these interrelated problems: coronal heating and the acceleration of the ambient solar wind. We also discuss where the community stands in its ability to forecast how variations in the solar wind (i.e., fast and slow wind streams) impact the Earth. Although the last few decades have seen significant progress in observations and modeling, we still do not have a complete understanding of the relevant physical processes, nor do we have a quantitatively precise census of which coronal structures contribute to specific types of solar wind. Fast streams are known to be connected to the central regions of large coronal holes. Slow streams, however, appear to come from a wide range of sources, including streamers, pseudostreamers, coronal loops, active regions, and coronal hole boundaries. Complicating our understanding even more is the fact that processes such as turbulence, stream-stream interactions, and Coulomb collisions can make it difficult to unambiguously map a parcel measured at 1 AU back down to its coronal source. We also review recent progress -- in theoretical modeling, observational data analysis, and forecasting techniques that sit at the interface between data and theory -- that gives us hope that the above problems are indeed solvable.Comment: Accepted for publication in Space Science Reviews. Special issue connected with a 2016 ISSI workshop on "The Scientific Foundations of Space Weather." 44 pages, 9 figure

Measurement of the Isolated Photon Cross Section in p-pbar Collisions at sqrt{s}=1.96 TeV

The cross section for the inclusive production of isolated photons has been measured in p anti-p collisions at sqrt{s}=1.96 TeV with the D0 detector at the Fermilab Tevatron Collider. The photons span transverse momenta 23 to 300 GeV and have pseudorapidity |eta|<0.9. The cross section is compared with the results from two next-to-leading order perturbative QCD calculations. The theoretical predictions agree with the measurement within uncertainties.Comment: 7 pages, 5 figures, submitted to Phys.Lett.

Aluminum oxide barrier coatings on polymer films for food packaging applications

In the field of packaging, barrier layers are functional films, which can be applied to polymeric substrates with the objective of enhancing their end-use properties. For food packaging applications, the packaging material is required to preserve packaged food stuffs and protect them from a variety of environmental influences, particularly moisture and oxygen ingress and UV radiation. Aluminum metallized films are widely used for this purpose. More recently, transparent barrier coatings based on aluminum oxide or silicon oxide have been introduced in order to fulfill requirements such as product visibility, microwaveability or retortability. With the demand for transparent barrier films for low-cost packaging applications growing, the use of high-speed vacuum deposition techniques, such as roll-to-roll metallizers, has become a favorable and powerful tool. In this study, aluminum oxide barrier coatings have been deposited onto biaxially oriented polypropylene and polyethylene terephthalate film substrates via reactive evaporation using an industrial 'boat-type' roll-to-roll metallizer. The coated films have been investigated and compared to uncoated films in terms of barrier properties, surface topography, roughness and surface energy using scanning electron microscopy, atomic force microscopy and contact angle measurement. Coating to substrate adhesion and coating thickness have been examined via peel tests and transmission electron microscopy, respectively. © 2013 Elsevier B.V

Genome-wide association and Mendelian randomisation analysis provide insights into the pathogenesis of heart failure

Heart failure (HF) is a leading cause of morbidity and mortality worldwide. A small proportion of HF cases are attributable to monogenic cardiomyopathies and existing genome-wide association studies (GWAS) have yielded only limited insights, leaving the observed heritability of HF largely unexplained. We report results from a GWAS meta-analysis of HF comprising 47,309 cases and 930,014 controls. Twelve independent variants at 11 genomic loci are associated with HF, all of which demonstrate one or more associations with coronary artery disease (CAD), atrial fibrillation, or reduced left ventricular function, suggesting shared genetic aetiology. Functional analysis of non-CAD-associated loci implicate genes involved in cardiac development (MYOZ1, SYNPO2L), protein homoeostasis (BAG3), and cellular senescence (CDKN1A). Mendelian randomisation analysis supports causal roles for several HF risk factors, and demonstrates CAD-independent effects for atrial fibrillation, body mass index, and hypertension. These findings extend our knowledge of the pathways underlying HF and may inform new therapeutic strategies

Measurement of the differential cross section for the production of an isolated photon with associated jet in ppbar collisions at sqrt(s)=1.96 TeV

The process ppbar -> photon + jet + X is studied using 1.0 fb^-1 of data collected by the D0 detector at the Fermilab Tevatron ppbar collider at a center-of-mass energy sqrt(s)=1.96 TeV. Photons are reconstructed in the central rapidity region |y_gamma|<1.0 with transverse momenta in the range 30<Pt_gamma<400 GeV while jets are reconstructed in either the central |y_jet|15 GeV. The differential cross section d^3sigma/dPt_gamma dy_gamma dy_jet is measured as a function of Pt_gamma in four regions, differing by the relative orientations of the photon and the jet in rapidity. Ratios between the differential cross sections in each region are also presented. Next-to-leading order QCD predictions using different parameterizations of parton distribution functions and theoretical scale choices are compared to the data. The predictions do not simultaneously describe the measured normalization and Pt_gamma dependence of the cross section in any of the four measured regions.Comment: 13 pages, 10 figure

The impact of employee perceptions of training on organisational commitment and turnover intentions: a study of multinationals in the Chinese service sector.

This study examines the impact of employee perceptions of training on organizational commitment, and the latter’s relationship with turnover intentions. Structured equation modelling is conducted on survey data from 437 Chinese employees of five multinational enterprises operating in the Chinese service sector. The results of the survey are consistent with social exchange theory. They highlight the importance of training as a tool to enhance the affective organisational commitment of employees, and reduce turnover. The findings differ from previous studies in non-Chinese settings. No evidence was found of any impact of motivation to learn and perceived benefits of training on organizational commitment. This may be explained by three factors; the involuntary nature of employee training, the limited career development opportunities on offer to local employees of multinational enterprises and the difficulty employees face in applying learnt skills given cultural differences. The implications for research and practice are discussed