Resonances in small scatterers with impedance boundary

With analytical (generalized Mie scattering) and numerical (integral-equation-based) considerations we show the existence of strong resonances in the scattering response of small spheres with lossless impedance boundary. With increasing size, these multipolar resonances are damped and shifted with respect to the magnitude of the surface impedance. The electric-type resonances are inductive and magnetic ones capacitive. Interestingly, these subwavelength resonances resemble plasmonic resonances in small negative-permittivity scatterers and dielectric resonances in small high-permittivity scatterers. The fundamental dipolar mode is also analyzed from the point of view of surface currents and the effect of the change of the shape into a non-spherical geometry

Status of COLDDIAG: A Cold Vacuum Chamber for Diagnostics

One of the still open issues for the development of superconducting insertion devices is the understanding of the beam heat load. With the aim of measuring the beam heat load to a cold bore and the hope to gain a deeper understanding in the beam heat load mechanisms, a cold vacuum chamber for diagnostics is under construction. The following diagnostics will be implemented: i) retarding field analyzers to measure the electron energy and flux, ii) temperature sensors to measure the total heat load, iii) pressure gauges, iv) and mass spectrometers to measure the gas content. The inner vacuum chamber will be removable in order to test different geometries and materials. This will allow the installation of the cryostat in different synchrotron light sources. COLDDIAG will be built to fit in a short straight section at ANKA. A first installation at the synchrotron light source Diamond is foreseen in June 2011. Here we describe the technical design report of this device and the planned measurements with beam.Comment: Presented at First International Particle Accelerator Conference, IPAC'10, Kyoto, Japan, from 23 to 28 May 201

Polarizability of conducting sphere-doublets using series of images.

The classical electrostatic problem of two nonintersecting conducting spheres in a uniform incident electric field is considered. Starting from the basic Kelvin’s image principle, the two spheres are replaced with equivalent series of image sources, from which the polarizability is calculated. Explicit expressions for the axial and transversal components of the polarizability dyadic are found by solving the recurrence equations. Efficient numerical evaluation of the different series is also discussed.Peer reviewe

Improved Linear Cryptanalysis of SOSEMANUK

Abstract. The SOSEMANUK stream cipher is one of the finalists of the eSTREAM project. In this paper, we improve the linear cryptanalysis of SOSEMANUK presented in Asiacrypt 2008. We apply the generalized linear masking technique to SOSEMANUK and derive many linear approximations holding with the correlations of up to 2 −25.5. We show that the data complexity of the linear attack on SOSEMANUK can be reduced by a factor of 2 10 if multiple linear approximations are used. Since SOSEMANUK claims 128-bit security, our attack would not be a real threat on the security of SOSEMANUK. Keywords: Stream Ciphers, Linear Cryptanalysis, SOSEMANUK, SOBER-128.

Citrullinated histone H3 as a novel prognostic blood marker in patients with advanced cancer

Citrullinated histone H3 (H3Cit) is a central player in the neutrophil release of nuclear chromatin, known as neutrophil extracellular traps (NETs). NETs have been shown to elicit harmful effects on the host, and were recently proposed to promote tumor progression and spread. Here we report significant elevations of plasma H3Cit in patients with advanced cancer compared with age-matched healthy individuals. These elevations were specific to cancer patients as no increase was observed in severely ill and hospitalized patients with a higher non-malignant comorbidity. The analysis of neutrophils from cancer patients showed a higher proportion of neutrophils positive for intracellular H3Cit compared to severely ill patients. Moreover, the presence of plasma H3Cit in cancer patients strongly correlated with neutrophil activation markers neutrophil elastase (NE) and myeloperoxidase (MPO), and the inflammatory cytokines interleukin-6 and -8, known to induce NETosis. In addition, we show that high levels of circulating H3Cit strongly predicted poor clinical outcome in our cohort of cancer patients with a 2-fold increased risk for short-term mortality. Our results also corroborate the association of NE, interleukin-6 and -8 with poor clinical outcome. Taken together, our results are the first to unveil H3Cit as a potential diagnostic and prognostic blood marker associated with an exacerbated inflammatory response in patients with advanced cancer

Is there an ideal way to initiate antiplatelet therapy with aspirin? A crossover study on healthy volunteers evaluating different dosing schemes with whole blood aggregometry

<p>Abstract</p> <p>Background</p> <p>Guidelines recommend an early initiation of aspirin treatment in patients with acute cerebral ischemia. Comparative studies on the best starting dose for initiating aspirin therapy to achieve a rapid antiplatelet effect do not exist. This study evaluated the platelet inhibitory effect in healthy volunteers by using three different aspirin loading doses to gain a model for initiating antiplatelet treatment in acute strokes patients.</p> <p>Methods</p> <p>Using whole blood aggregometry, this study with a prospective, uncontrolled, open, crossover design examined 12 healthy volunteers treated with three different aspirin loading doses: intravenous 500 mg aspirin, oral 500 mg aspirin, and a course of 200 mg aspirin on two subsequent days followed by a five-day course of 100 mg aspirin. Aspirin low response was defined as change of impedance exceeding 0 Ω after stimulation with arachidonic acid.</p> <p>Results</p> <p>Sufficient antiplatelet effectiveness was gained within 30 seconds when intravenous 500 mg aspirin was used. The mean time until antiplatelet effect was 74 minutes for 500 mg aspirin taken orally and 662 minutes (11.2 hours) for the dose scheme with 200 mg aspirin with a high inter- and intraindividual variability in those two regimes. Platelet aggregation returned to the baseline range during the wash-out phase within 4 days.</p> <p>Conclusion</p> <p>Our study reveals that the antiplatelet effect differs significantly between the three different aspirin starting dosages with a high inter- and intraindividual variability of antiplatelet response in our healthy volunteers. To ensure an early platelet inhibitory effect in acute stroke patients, it could be advantageous to initiate the therapy with an intravenous loading dose of 500 mg aspirin. However, clinical outcome studies must still define the best way to initiate antiplatelet treatment with aspirin.</p

Neutrophils and neutrophil extracellular traps enhance venous thrombosis in mice bearing human pancreatic tumors

Pancreatic cancer is associated with a high incidence of venous thromboembolism. Neutrophils have been shown to contribute to thrombosis in part by releasing neutrophil extracellular traps (NET). A recent study showed that increased plasma levels of the NET biomarker, citrullinated histone H3 (H3Cit), are associated with venous thromboembolism in patients with pancreatic and lung cancer but not in those with other types of cancer, including breast cancer. In this study, we examined the contribution of neutrophils and NET to venous thrombosis in nude mice bearing human pancreatic tumors. We found that tumor-bearing mice had increased circulating neutrophil counts and levels of granulocyte-colony stimulating factor, neutrophil elastase, H3Cit and cell-free DNA compared with controls. In addition, thrombi from tumor-bearing mice contained increased levels of the neutrophil marker Ly6G, as well as higher levels of H3Cit and cell-free DNA. Thrombi from tumor-bearing mice also had denser fibrin with thinner fibers consistent with increased thrombin generation. Importantly, either neutrophil depletion or administration of DNase I reduced the thrombus size in tumor-bearing but not in control mice. Our results, together with clinical data, suggest that neutrophils and NET contribute to venous thrombosis in patients with pancreatic cancer

Stress and prevalence of hearing problems in the Swedish working population

<p>Abstract</p> <p>Background</p> <p>Current human and experimental studies are indicating an association between stress and hearing problems; however potential risk factors have not been established. Hearing problems are projected to become among the top ten disabilities according to the WHO in the near future. Therefore a better understanding of the relationships between stress and hearing is warranted. Here we describe the prevalence of two common hearing problems, i.e. hearing complaints and tinnitus, in relation to different work-and health-related stressors.</p> <p>Methods</p> <p>A total of 18,734 individuals were invited to participate in the study, out of which 9,756 (52%) enrolled.</p> <p>Results</p> <p>The results demonstrate a clear and mostly linear relationship between higher prevalence of hearing problems (tinnitus or hearing loss or both) and different stressors, e.g. occupational, poorer self-rated health, long-term illness, poorer sleep quality, and higher burnout scores.</p> <p>Conclusions</p> <p>The present study unambiguously demonstrates associations between hearing problems and various stressors that have not been previously described for the auditory system. These findings will open new avenues for future investigations.</p

Androgen regulation of the androgen receptor coregulators

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