Aspects of the Mass Distribution of Interstellar Dust Grains in the Solar System from In-Situ Measurements

The in-situ detection of interstellar dust grains in the Solar System by the dust instruments on-board the Ulysses and Galileo spacecraft as well as the recent measurements of hyperbolic radar meteors give information on the properties of the interstellar solid particle population in the solar vicinity. Especially the distribution of grain masses is indicative of growth and destruction mechanisms that govern the grain evolution in the interstellar medium. The mass of an impacting dust grain is derived from its impact velocity and the amount of plasma generated by the impact. Because the initial velocity and the dynamics of interstellar particles in the Solar System are well known, we use an approximated theoretical instead of the measured impact velocity to derive the mass of interstellar grains from the Ulysses and Galileo in-situ data. The revised mass distributions are steeper and thus contain less large grains than the ones that use measured impact velocities, but large grains still contribute significantly to the overall mass of the detected grains. The flux of interstellar grains with masses $> 10^{-14} {\rm kg}$ is determined to be $1\cdot 10^{-6} {\rm m}^{-2} {\rm s}^{-1}$. The comparison of radar data with the extrapolation of the Ulysses and Galileo mass distribution indicates that the very large ($m > 10^{-10} {\rm kg}$) hyperbolic meteoroids detected by the radar are not kinematically related to the interstellar dust population detected by the spacecraft.Comment: 14 pages, 11 figures, to appear in JG

Mission design for LISA Pathfinder

Here we describe the mission design for SMART-2/LISA Pathfinder. The best trade-off between the requirements of a low-disturbance environment and communications distance is found to be a free-insertion Lissajous orbit around the first co-linear Lagrange point of the Sun-Earth system L1, 1.5x 10^6 km from Earth. In order to transfer SMART-2/LISA Pathfinder from a low Earth orbit, where it will be placed by a small launcher, the spacecraft carries out a number of apogee-raise manoeuvres, which ultimatively place it to a parabolic escape trajectory towards L1. The challenges of the design of a small mission are met, fulfilling the very demanding technology demonstration requirements without creating excessive requirements on the launch system or the ground segment.Comment: 7 pages, 6 figures, 5th International LISA Symposium, see http://www.landisoft.de/Markus-Landgra

High Rate Performance of Drift Tubes

This article describes calculations and measurements of space charge effects due to high rate irradiation in high resolution drift tubes. Two main items are studied: the reduction of the gas gain and changes of the drift time. Whereas the gain reduction is similar for all gases and unavoidable, the drift time changes depend on the kind of gas that is used. The loss in resolution due to high particle rate can be minimized with a suitable gas. This behaviour is calculable, allowing predictions for new gas mixtures.Comment: 20 pages, submitted to Nuclear Instruments and Methods

Development of the A/H6N1 influenza vaccine candidate based on A/Leningrad/134/17/57 (H2N2) master donor virus and the genome composition analysis using high resolution melting (HRM)

The avian influenza viruses of H6N1subtype present a potential danger for humans. The cold-adapted (ca) reassortant influenza virus А/17/herring gull/Sarma/2006/887 (H6N1) was obtained in chicken embryos by the genetic reassortment based on the coldadapted A/Leningrad/134/17/57 (H2N2) master strain. The genome composition of the obtained reassortant was analyzed by means of real-time PCR with the high resolution melting (HRM) analysis using the intercalating fluorescent dye EvaGreen. Analysis of the gene segments showed that the reassortant А/17/herring gull/Sarma/2006/887 (H6N1) contains the internal proteins coding genes (PB2, PB1, PA, NP, M, and NS) of the master donor virus and the surface antigens coding genes of the A/herring gull/Sarma/51c/2006 (H6N1) avian influenza virus. The study of the phenotypic properties showed that the virus А/17/herring gull/Sarma/2006/887 (H6N1) is temperature sensitive (ts), ca in chicken embryos, and attenuated in mice when administered intranasally. This reassortant can be recommended as a live influenza vaccine candidate for humans.The avian influenza viruses of H6N1subtype present a potential danger for humans. The cold-adapted (ca) reassortant influenza virus А/17/herring gull/Sarma/2006/887 (H6N1) was obtained in chicken embryos by the genetic reassortment based on the coldadapted A/Leningrad/134/17/57 (H2N2) master strain. The genome composition of the obtained reassortant was analyzed by means of real-time PCR with the high resolution melting (HRM) analysis using the intercalating fluorescent dye EvaGreen. Analysis of the gene segments showed that the reassortant А/17/herring gull/Sarma/2006/887 (H6N1) contains the internal proteins coding genes (PB2, PB1, PA, NP, M, and NS) of the master donor virus and the surface antigens coding genes of the A/herring gull/Sarma/51c/2006 (H6N1) avian influenza virus. The study of the phenotypic properties showed that the virus А/17/herring gull/Sarma/2006/887 (H6N1) is temperature sensitive (ts), ca in chicken embryos, and attenuated in mice when administered intranasally. This reassortant can be recommended as a live influenza vaccine candidate for humans

SU(2Nf)⊗O(3)SU(2N_{f})\otimes O(3) light diquark symmetry and current-induced heavy baryon transition form factors

We study the current-induced bottom baryon to charm baryon transitions in the Heavy Quark Symmetry limit as $m_{q}\rightarrow \infty$. Our discussion involves $s$-wave to $s$-wave as well as $s$-wave to $p$-wave transitions. Using a constituent quark model picture for the light diquark system with an underlying $SU(2N_{f})\otimes O(3)$ symmetry and the heavy quark symmetry we arrive at a number of new predictions for the reduced form factors that describe these transitions.Comment: Corrected spelling mistake in title, 19 pages, latex, no figure

Outcome of renal grafts after simultaneous kidney/ pancreas transplantation

Nineteen patients with endstage renal failure due to Type 1 (insulin-dependent) diabetes mellitus received simultaneous pancreas/kidney transplants using bladder drainage technique. Another group of 25 Type 1 diabetic patients received pancreas/kidney transplants by the duct occlusion technique. We observed a higher incidence of rejection episodes in the patients of the bladder drainage group than those in the duct occlusion group, 14 of 19 patients (74%) vs 7 of 25 (28%) respectively. Anti CD3 antibodies (Orthoclone, OKT3) as a part of induction treatment was used more often in the bladder drainage group (58%) than in the control group (20%)

Follow-up study of sensory-motor polyneuropathy in Type 1 (insulin-dependent) diabetic subjects after simultaneous pancreas and kidney transplantation and after graft rejection

The influence of successful simultaneous pancreas and kidney transplantation on peripheral polyneuropathy was investigated in 53 patients for a mean observation period of 40.3 months. Seventeen patients were followed-up for more than 3 years. Symptoms and signs were assessed every 6 months using a standard questionnaire, neurological examination and measurement of sensory and motor nerve conduction velocities. While symptoms of polyneuropathy improved (pain, paraesthesia, cramps, restless-legs) and nerve conduction velocity increased, there was no change of clinical signs (sensation, muscle-force, tendon-reflexes). Following kidney-graft-rejection there was a slight decrease of nerve conduction verlocity during the first year, which was not statistically significant. Following pancreas-graft rejection there was no change of nerve conduction velocity during the first year. Comparing the maximum nerve conduction velocity of the patients with pancreas-graft-rejection to the nerve conduction velocities of these patients at the end of the study, there was a statistically significant decrease of 6.5 m/s. In conclusion, we believe that strict normalization of glucose metabolism alters the progressive course of diabetic polyneuropathy. It may be stabilized or partly reversed after successful grafting even in long-term diabetic patients