The V_H gene repertoire of splenic B cells and somatic hypermutation in systemic lupus erythematosus

In systemic lupus erythematosus (SLE) it has been hypothesized that self-reactive B cells arise from virgin B cells that express low-affinity, nonpathogenic germline V genes that are cross-reactive for self and microbial antigens, which convert to high-affinity autoantibodies via somatic hypermutation. The aim of the present study was to determine whether the V<sub>H</sub> family repertoire and pattern of somatic hypermutation in germinal centre (GC) B cells deviates from normal in SLE. Rearranged immunoglobulin V<sub>H</sub> genes were cloned and sequenced from GCs of a SLE patient's spleen. From these data the GC V gene repertoire and the pattern of somatic mutation during the proliferation of B-cell clones were determined. The results highlighted a bias in V<sub>H</sub>5 gene family usage, previously unreported in SLE, and under-representation of the V<sub>H</sub>1 family, which is expressed in 20–30% of IgM+ B cells of healthy adults and confirmed a defect in negative selection. This is the first study of the splenic GC response in human SLE

Lessons and Prospects from the pMSSM after LHC Run I: Neutralino LSP

We study SUSY signatures at the 7, 8 and 14 TeV LHC employing the 19-parameter, R-Parity conserving p(henomenological)MSSM, in the scenario with a neutralino LSP. Our results were obtained via a fast Monte Carlo simulation of the ATLAS SUSY analysis suite. The flexibility of this framework allows us to study a wide variety of SUSY phenomena simultaneously and to probe for weak spots in existing SUSY search analyses. We determine the ranges of the sparticle masses that are either disfavored or allowed after the searches with the 7 and 8 TeV data sets are combined. We find that natural SUSY models with light squarks and gluinos remain viable. We extrapolate to 14 TeV with both 300 fb$^{-1}$ and 3 ab$^{-1}$ of integrated luminosity and determine the expected sensitivity of the jets + MET and stop searches to the pMSSM parameter space. We find that the high-luminosity LHC will be powerful in probing SUSY with neutralino LSPs and can provide a more definitive statement on the existence of natural Supersymmetry.Comment: 41 pages, 27 figures. arXiv admin note: substantial text overlap with arXiv:1307.844

Density Matrix Renormalization for Model Reduction in Nonlinear Dynamics

We present a novel approach for model reduction of nonlinear dynamical systems based on proper orthogonal decomposition (POD). Our method, derived from Density Matrix Renormalization Group (DMRG), provides a significant reduction in computational effort for the calculation of the reduced system, compared to a POD. The efficiency of the algorithm is tested on the one dimensional Burgers equations and a one dimensional equation of the Fisher type as nonlinear model systems.Comment: 12 pages, 12 figure

Linear models for control of cavity flow oscillations

Models for understanding and controlling oscillations in the flow past a rectangular cavity are developed. These models may be used to guide control designs, to understand performance limits of feedback, and to interpret experimental results. Traditionally, cavity oscillations are assumed to be self-sustained: no external disturbances are necessary to maintain the oscillations, and amplitudes are limited by nonlinearities. We present experimental data which suggests that in some regimes, the oscillations may not be self-sustained, but lightly damped: oscillations are sustained by external forcing, such as boundary-layer turbulence. In these regimes, linear models suffice to describe the behaviour, and the final amplitude of oscillations depends on the characteristics of the external disturbances. These linear models are particularly appropriate for describing cavities in which feedback has been used for noise suppression, as the oscillations are small and nonlinearities are less likely to be important. It is shown that increasing the gain too much in such feedback control experiments can lead to a peak-splitting phenomenon, which is explained by the linear models. Fundamental performance limits indicate that peak splitting is likely to occur for narrow-bandwidth actuators and controllers

Soil Nutrients and Vegetation Characteristics of a Dorset/Thule Site in the Canadian Arctic

We conducted a systematic study of soils and vegetation present at Arnaqquaksaat on Igloolik Island, Nunavut, a site occupied by Dorset and Thule people prior to 1823 and probably for over a thousand years. We compared this site to an area affected by ongoing mammal and bird activity and an area of relatively unfertilized polar semidesert. At these locations, we estimated percent cover of vegetation, identified vascular plant species, measured soil depth, and collected soil samples. The soil samples were analyzed for total nitrogen, sodium bicarbonate-extractable phosphorus, available potassium, available magnesium, and pH.Percent plant cover, abundance of plant species indicative of enrichment, and soil depth were greatest within the area of anthropogenic influence and decreased downslope to the sea. Total nitrogen level in the upslope area of anthropogenic influence (2.61% ±0.88) was similar to that in areas of bird and mammal activity (2.54% ±0.78); it was higher than the levels in the downslope area of human fertilization (0.65% ±0.82) and the unaltered polar semidesert area (0.28% ±0.38). Phosphorus levels in the influenced areas were 5 to 6 times those in the uninfluenced polar semidesert. The magnesium level was highest in the area of bird and mammal activity (766.8 mg/L ±53.35), whereas potassium levels were similar throughout the study area. The lowest pH was found in the upslope area of past human occupation, and pH differences among sites paralleled those observed for nitrogen.On a effectué une étude systématique des sols et de la végétation présents à Arnaqquaksaat dans l'île Igloolik au Nunavut, un site occupé par les peuples de Dorset et de Thulé avant 1823 et probablement durant plus de mille ans. On a comparé ce site à une zone affectée par l'activité continue de mammifères et d'oiseaux et à une zone de semi-désert polaire relativement non fertilisé. À ces endroits, on a évalué le pourcentage de couvert végétal, identifié les espèces de plantes vasculaires, mesuré la profondeur du sol et prélevé des échantillons de sol. On a analysé ces derniers pour en évaluer la teneur en azote total, phosphore extractible par le bicarbonate de soude, potassium disponible, magnésium disponible et le pH. On a trouvé que le pourcentage de couvert végétal, l'abondance d'espèces végétales révélatrice d'un enrichissement et la profondeur du sol étaient les plus importants à l'intérieur de la zone qui avait subi une influence anthropique et qu'ils décroissaient en descendant vers la mer. Le niveau d'azote total dans la zone supérieure de la pente, qui avait subi une influence anthropique (2,61 p. cent ± 0,88), était semblable à celui des zones où s'exerçait l'activité des oiseaux et des mammifères (2,54 p. cent ± 0,78); il était supérieur aux niveaux trouvés dans la partie inférieure qui avait connu une fertilisation humaine (0,65 p. cent ± 0,82) et dans la zone polaire semi-désertique non altérée (0,28 ± 0,38). Les niveaux de phosphore dans les zones ayant subi une influence étaient de 5 à 6 fois ceux des zones semi-désertiques polaires n'ayant pas subi d'influence. Le niveau de magnésium était le plus haut dans la zone où s'exerçait l'activité des oiseaux et des mammifères (766,8 mg/L ± 53,35), alors que les niveaux de potassium étaient semblables dans toute la zone d'étude. Le pH le plus bas se trouvait dans la zone supérieure de l'endroit ayant jadis été occupé par l'être humain, et les différences dans le pH parmi les sites s'alignaient sur celles observées pour l'azote

Japanese multinationals in the post-bubble era:new challenges and evolving capabilities

Since the bursting of Japan's bubble economy, from 1990 onwards, Japanese multinational companies (MNCs) have faced new competitive challenges and questions about the management practices on which they had built their initial success in global markets. Japanese engagement in the international economy has undergone a number of phases. In the period before the Second World War, Japanese companies learnt from foreign MNCs in trading, shipping, and manufacturing, frequently through strategic alliances, and leveraged their capabilities to succeed in overseas and largely Asian markets. In the immediate post-war decades, during the Japanese ‘economic miracle’, there were notable examples of MNC investment in raw materials and labour intensive production, but both inward and outward foreign direct investment were not significant. Japanese companies achieved leadership in management and technology, in order to support a strategy of export-orientated industrialization. Changes in government policies in the developed economies of the US and Western Europe forced leading Japanese manufacturers to convert themselves into MNCs and to transfer their home-grown capabilities to overseas subsidiaries. The period after 1990 marked declining Japanese competitiveness and it asked questions about the ability of Japanese MNCs to be more responsive and global in their strategies, organization and capabilities.No Full Tex

Use of domesticated pigs by Mesolithic hunter-gatherers in northwestern Europe

Acknowledgements We thank the Archaeological State Museum Schleswig-Holstein, the Archaeological State Offices of Brandenburg, Lower Saxony and Saxony and the following individuals who provided sample material: Betty Arndt, Jo¨rg Ewersen, Frederick Feulner, Susanne Hanik, Ru¨diger Krause, Jochen Reinhard, Uwe Reuter, Karl-Heinz Ro¨hrig, Maguerita Scha¨fer, Jo¨rg Schibler, Reinhold Schoon, Regina Smolnik, Thomas Terberger and Ingrid Ulbricht. We are grateful to Ulrich Schmo¨lcke, Michael Forster, Peter Forster and Aikaterini Glykou for their support and comments on the manuscript. We also thank many institutions and individuals that provided sample material and access to collections, especially the curators of the Museum fu¨r Naturkunde, Berlin; Muse´um National d0 Histoire Naturelle, Paris; Smithsonian Institution, National Museum of Natural History, Washington D.C.; Zoologische Staatssammlung, Mu¨nchen; Museum fu¨r Haustierkunde, Halle; the American Museum of Natural History, New-York. This work was funded by the Graduate School ‘Human Development in Landscapes’ at Kiel University (CAU) and supported by NERC project Grant NE/F003382/1. Radiocarbon dating was carried out at the Leibniz Laboratory, CAU. This work is licensed under a Creative Commons AttributionNonCommercial-NoDerivs 3.0 Unported License.Peer reviewedPublisher PD

Morphological and Mechanical Biomimetic Bone Structures

© 2016 American Chemical Society. Cortical bone is an example of a mineralized tissue containing a compositional distribution of hard and soft phases in 3-dimensional space for mechanical function. X-ray computed tomography (XCT) is able to describe this compositional and morphological complexity but methods to provide a physical output with comparable mechanical function is lacking. A workflow is presented here to establish a method of using high contrast XCT to establish a virtual model of cortical bone that is manufactured using a multiple material capable 3D printer. Resultant 3D printed structures were produced based on more and less remodelled bone designs exhibiting a range of secondary osteon density. Variation in resultant mechanical properties of the 3D printed composite structures for each bone design was achieved using a combination of material components and reasonable prediction of elastic modulus provided using a Hashin-Shtrikman approach. The ability to 3D print composite structures using high contrast XCT to distinguish between compositional phases in a biological structure promises improved anatomical models as well as next-generation mechano-mimetic implants