317 research outputs found

    Sensing inertial rotation with tuning forks

    Get PDF

    Sequential Combination Therapy Leading to Sustained Remission in a Patient with SAPHO Syndrome

    Get PDF
    The SAPHO syndrome represents a variety of clinically similar disorders with the key features of hyperostotic bone lesions in combination with chronic pustular skin disease. The respective pathophysiology of bone and joint manifestations in SAPHO syndrome is still a matter of discussion. For example it does not appear to represent reactive arthritis and HLA B27 antigen, with the latter being typically present in patients with spondyloarthopathies. Treatment of SAPHO syndrome is also not well established and consists of various antiinflammatory and antirheumatic drugs. Here, we report a female patient with active SAPHO syndrome suffering from sternal swelling of unknown origin that had been known for 10 years and a 4-year-history of severe lower back pain. Remarkable were also a typical pustulous palmar erythema associated with swelling and decreased motility of both MCP-I joints. Inflammation parameters were high with an ESR 68 mm/1st hour and a CRP of 19.6 mg/l. She was initially treated with rofecoxib and doxycycline, followed by sulfasalazine with only partial clinical response. Thereafter, both articular symptoms as well as cutaneous lesions responded well to a combination therapy with methotrexate and sulfasalazine. Thus, the case illustrates nicely that methotrexate in combination with another DMARD can be successfully applied to patients with long-term active SAPHO syndrome

    Perfect Secrecy Systems Immune to Spoofing Attacks

    Full text link
    We present novel perfect secrecy systems that provide immunity to spoofing attacks under equiprobable source probability distributions. On the theoretical side, relying on an existence result for tt-designs by Teirlinck, our construction method constructively generates systems that can reach an arbitrary high level of security. On the practical side, we obtain, via cyclic difference families, very efficient constructions of new optimal systems that are onefold secure against spoofing. Moreover, we construct, by means of tt-designs for large values of tt, the first near-optimal systems that are 5- and 6-fold secure as well as further systems with a feasible number of keys that are 7-fold secure against spoofing. We apply our results furthermore to a recently extended authentication model, where the opponent has access to a verification oracle. We obtain this way novel perfect secrecy systems with immunity to spoofing in the verification oracle model.Comment: 10 pages (double-column); to appear in "International Journal of Information Security

    Optimum electrode configurations for fast ion separation in microfabricated surface ion traps

    Full text link
    For many quantum information implementations with trapped ions, effective shuttling operations are important. Here we discuss the efficient separation and recombination of ions in surface ion trap geometries. The maximum speed of separation and recombination of trapped ions for adiabatic shuttling operations depends on the secular frequencies the trapped ion experiences in the process. Higher secular frequencies during the transportation processes can be achieved by optimising trap geometries. We show how two different arrangements of segmented static potential electrodes in surface ion traps can be optimised for fast ion separation or recombination processes. We also solve the equations of motion for the ion dynamics during the separation process and illustrate important considerations that need to be taken into account to make the process adiabatic

    Origin of Life

    Full text link
    The evolution of life has been a big enigma despite rapid advancements in the fields of biochemistry, astrobiology, and astrophysics in recent years. The answer to this puzzle has been as mind-boggling as the riddle relating to evolution of Universe itself. Despite the fact that panspermia has gained considerable support as a viable explanation for origin of life on the Earth and elsewhere in the Universe, the issue remains far from a tangible solution. This paper examines the various prevailing hypotheses regarding origin of life like abiogenesis, RNA World, Iron-sulphur World, and panspermia; and concludes that delivery of life-bearing organic molecules by the comets in the early epoch of the Earth alone possibly was not responsible for kick-starting the process of evolution of life on our planet.Comment: 32 pages, 8 figures,invited review article, minor additio

    Evaluation of hydrochars from lignin hydrous pyrolysis to produce biocokes after carbonization

    Get PDF
    Hydrochars were obtained after hydrous pyrolysis of a pine Kraft lignin using different reaction conditions (temperature, water content and residence time) and the residues were characterized through a wide range of analytical techniques including high-temperature rheometry, solid-state 13C nuclear magnetic resonance (NMR), thermal gravimetric analysis (TGA), diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and field emission scanning electron microscopy (FE-SEM). The results indicated that an increase in reaction temperature, an increase in residence time or a decrease in water content reduces the amount of fluid material in the residue. The hydrous pyrolysis conditions studied were not able to increase the maturation of lignin, which would result in an increase in the resolidification temperature, but reduced the amount of mineral matter in the hydrochar produced. On the other hand, the hydrochars obtained from pristine lignin, torrefied lignin (300 °C, 1 h) and their 50:50 wt.%/wt.% blend at temperatures of 350 °C after 6 h using 30 ml of water had lower ash contents (45%) is excessively high compared to that of the good coking coal (10%) and the micro-strength of the biocokes (R139%) and high microporous surface areas ( > 400 m2/g) of the biocokes and high alkalinity index of the lignins (>27%) compared to those of the coke (27% and 145 m2/g) and coal (0.6%), respectively. Furthermore, the biocoke derived from the hydrous pyrolysed torrefied lignin did not agglomerate, which could not be explained by changes in the chemical properties of the material and requires further investigation

    Charged pion form factor between Q^2=0.60 and 2.45 GeV^2. II. Determination of, and results for, the pion form factor

    Get PDF
    The charged pion form factor, Fpi(Q^2), is an important quantity which can be used to advance our knowledge of hadronic structure. However, the extraction of Fpi from data requires a model of the 1H(e,e'pi+)n reaction, and thus is inherently model dependent. Therefore, a detailed description of the extraction of the charged pion form factor from electroproduction data obtained recently at Jefferson Lab is presented, with particular focus given to the dominant uncertainties in this procedure. Results for Fpi are presented for Q^2=0.60-2.45 GeV^2. Above Q^2=1.5 GeV^2, the Fpi values are systematically below the monopole parameterization that describes the low Q^2 data used to determine the pion charge radius. The pion form factor can be calculated in a wide variety of theoretical approaches, and the experimental results are compared to a number of calculations. This comparison is helpful in understanding the role of soft versus hard contributions to hadronic structure in the intermediate Q^2 regime.Comment: 18 pages, 11 figure

    Virtual Compton Scattering and Neutral Pion Electroproduction in the Resonance Region up to the Deep Inelastic Region at Backward Angles

    Full text link
    We have made the first measurements of the virtual Compton scattering (VCS) process via the H(e,ep)γ(e,e'p)\gamma exclusive reaction in the nucleon resonance region, at backward angles. Results are presented for the WW-dependence at fixed Q2=1Q^2=1 GeV2^2, and for the Q2Q^2-dependence at fixed WW near 1.5 GeV. The VCS data show resonant structures in the first and second resonance regions. The observed Q2Q^2-dependence is smooth. The measured ratio of H(e,ep)γ(e,e'p)\gamma to H(e,ep)π0(e,e'p)\pi^0 cross sections emphasizes the different sensitivity of these two reactions to the various nucleon resonances. Finally, when compared to Real Compton Scattering (RCS) at high energy and large angles, our VCS data at the highest WW (1.8-1.9 GeV) show a striking Q2Q^2- independence, which may suggest a transition to a perturbative scattering mechanism at the quark level.Comment: 20 pages, 8 figures. To appear in Phys.Rev.
    corecore