Production of Lambda and Sigma^0 hyperons in proton-proton collisions

This paper reports results on simultaneous measurements of the reaction channels pp -> pK+\Lambda and pp -> pK+\Sigma^0 at excess energies of 204, 239, and 284 MeV (\Lambda) and 127, 162, and 207 MeV (\Sigma^0). Total and differential cross sections are given for both reactions. It is concluded from the measured total cross sections that the high energy limit of the cross section ratio is almost reached at an excess energy of only about 200 MeV. From the differential distributions observed in the overall CMS as well as in the Jackson and helicity frames, a significant contribution of interfering nucleon resonances to the \Lambda production mechanism is concluded while resonant \Sigma^0-production seems to be of lesser importance and takes place only through specific partial waves of the entrance channel. The data also indicate that kaon exchange plays a minor role in the case of \Lambda- but an important role for \Sigma^0-production. Thus the peculiar energy dependence of the \Lambda-to-\Sigma^0 cross section ratio appears in a new light as its explanation requires more than mere differences between the p\Lambda and the p\Sigma^0 final state interaction. The data provide a benchmark for theoretical models already available or yet to come.Comment: 18 pages, 10 figures; accepted by The European Physical Journal A (EPJ A

An aminostratigraphy for the British Quaternary based on Bithynia opercula

Aminostratigraphies of Quaternary non-marine deposits in Europe have been previously based on the racemization of a single amino acid in aragonitic shells from land and freshwater molluscs. The value of analysing multiple amino acids from the opercula of the freshwater gastropod Bithynia, which are composed of calcite, has been demonstrated. The protocol used for the isolation of intra-crystalline proteins from shells has been applied to these calcitic opercula, which have been shown to more closely approximate a closed system for indigenous protein residues. Original amino acids are even preserved in bithyniid opercula from the Eocene, showing persistence of indigenous organics for over 30 million years. Geochronological data from opercula are superior to those from shells in two respects: first, in showing less natural variability, and second, in the far better preservation of the intra-crystalline proteins, possibly resulting from the greater stability of calcite. These features allow greater temporal resolution and an extension of the dating range beyond the early Middle Pleistocene. Here we provide full details of the analyses for 480 samples from 100 horizons (75 sites), ranging from Late Pliocene to modern. These show that the dating technique is applicable to the entire Quaternary. Data are provided from all the stratotypes from British stages to have yielded opercula, which are shown to be clearly separable using this revised method. Further checks on the data are provided by reference to other type-sites for different stages (including some not formally defined). Additional tests are provided by sites with independent geochronology, or which can be associated with a terrace stratigraphy or biostratigraphy. This new aminostratigraphy for the non-marine Quaternary deposits of southern Britain provides a framework for understanding the regional geological and archaeological record. Comparison with reference to sites yielding independent geochronology, in combination with other lines of evidence, allows tentative correlation with the marine oxygen isotope record

To align or not to align? Research methods and its relationship with dissertation marks across sport undergraduate degree programmes within a UK-based HE institution

Much research has referred to the complexity of research methods modules within undergraduate degree programmes. Less attention has been paid to the objective understanding of alignment between research methods and final year dissertations. This study explored relationships across Sport and Exercise Science (SES) and Sports Therapy (ST) programmes within a UK-based Higher Education institution. Analysis revealed females (N=73) outperformed males (N=117) at Levels 4/5, and SES students outperformed ST at Level 6. The Level 5 statistics assessment explained the lowest variance in the dissertation, suggesting poor alignment in curriculum design. Future research should consider the efficacy of statistics-based modules

Survey of Surveys (SoS) ‐ Mapping The Landscape of Survey Papers in Information Visualization

Information visualization as a field is growing rapidly in popularity since the first information visualization conference in 1995.However, as a consequence of its growth, it is increasingly difficult to follow the growing body of literature within the field.Survey papers and literature reviews are valuable tools for managing the great volume of previously published research papers,and the quantity of survey papers in visualization has reached a critical mass. To this end, this survey paper takes a quantumstep forward by surveying and classifying literature survey papers in order to help researchers understand the current landscapeof Information Visualization. It is, to our knowledge, the first survey of survey papers (SoS) in Information Visualization. Thispaper classifies survey papers into natural topic clusters which enables readers to find relevant literature and develops thefirst classification of classifications. The paper also enables researchers to identify both mature and less developed researchdirections as well as identify future directions. It is a valuable resource for both newcomers and experienced researchers in andoutside the field of Information Visualization and Visual Analytic