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We propose to install a storage ring at an ISOL-type radioactive beam facility for the first time. Specifically, we intend to setup the heavy-ion, low-energy ring TSR at the HIE-ISOLDE facility in CERN, Geneva. Such a facility will provide a capability for experiments with stored secondary beams that is unique in the world. The envisaged physics programme is rich and varied, spanning from investigations of nuclear ground-state properties and reaction studies of astrophysical relevance, to investigations with highly-charged ions and pure isomeric beams. The TSR might also be employed for removal of isobaric contaminants from stored ion beams and for systematic studies within the neutrino beam programme. In addition to experiments performed using beams recirculating within the ring, cooled beams can also be extracted and exploited by external spectrometers for high-precision measurements. The existing TSR, which is presently in operation at the Max-Planck Institute for Nuclear Physics in Heidelberg, is well-suited and can be employed for this purpose. The physics cases as well as technical details of the existing ring facility and of the beam and infrastructure requirements at HIE-ISOLDE are discussed in the present technical design report.

Cardiovascular diseases account for more than half of total mortality before the age of 75 in industrialized countries. To develop therapies promoting the compensatory growth of blood vessels could be superior to palliative surgical surgical interventions. Therefore, much effort has been put into investigating underlying mechanisms. Depending on the initial trigger, growth of blood vessels in adult organisms proceeds viatwo major processes, angiogenesis and arteriogenesis. While angiogenesis is induced by hypoxia and results in new capillaries, arteriogenesis is induced by physical forces, most importantly fluid shear stress. Consequently, chronically elevated fluid shear stress was found to be the strongest trigger under experimental conditions. Arteriogenesis describes the remodelling of pre‐existing arterio‐arteriolar anastomoses to completely developed and functional arteries. In both growth processes, enlargement of vascular wall structures was proposed to be covered by proliferation of existing wall cells. Recently, increasing evidence emerges, implicating a pivotal role for circulating cells, above all blood monocytes, in vascular growth processes. Since it has been shown that monocytes/macrophage release a cocktail of chemokines, growth factors and proteases involved in vascular growth, their contribution seems to be of a paracrine fashion. A similar role is currently discussed for various populations of bone‐marrow derived stem cells and endothelial progenitors. In contrast, the initial hypothesis that these cells ‐after undergoing a (trans‐)differentiation‐ contribute by a structural integration into the growing vessel wall, is increasingly challenged.

We present the first mathematical model to account for the evolution of the abdominal aortic aneurysm. The artery is modelled as a two-layered, cylindrical membrane using nonlinear elasticity and a physiologically realistic constitutive model. It is subject to a constant systolic pressure and a physiological axial prestretch. The development of the aneurysm is assumed to be a consequence of the remodelling of its material constituents. Microstructural ‘recruitment’ and fibre density variables for the collagen are introduced into the strain energy density functions. This enables the remodelling of collagen to be addressed as the aneurysm enlarges. An axisymmetric aneurysm, with axisymmetric degradation of elastin and linear differential equations for the remodelling of the fibre variables, is simulated numerically. Using physiologically determined parameters to model the abdominal aorta and realistic remodelling rates for its constituents, the predicted dilations of the aneurysm are consistent with those observed in vivo. An asymmetric aneurysm with spinal contact is also modelled, and the stress distributions are consistent with previous studies.We present the first mathematical model to account for the evolution of the abdominal aortic aneurysm. The artery is modelled as a two-layered, cylindrical membrane using nonlinear elasticity and a physiologically realistic constitutive model. It is subject to a constant systolic pressure and a physiological axial prestretch. The development of the aneurysm is assumed to be a consequence of the remodelling of its material constituents. Microstructural ‘recruitment’ and fibre density variables for the collagen are introduced into the strain energy density functions. This enables the remodelling of collagen to be addressed as the aneurysm enlarges. An axisymmetric aneurysm, with axisymmetric degradation of elastin and linear differential equations for the remodelling of the fibre variables, is simulated numerically. Using physiologically determined parameters to model the abdominal aorta and realistic remodelling rates for its constituents, the predicted dilations of the aneurysm are consistent with those observed in vivo. An asymmetric aneurysm with spinal contact is also modelled, and the stress distributions are consistent with previous studies.

DANCE (Device for Advanced Neutron Capture Experiments) is a 4π162 element BaF2array under development at Los Alamos National Laboratory. It is designed to provide high granularity, fast timing and high photon detection efficiency. It will be located at the Los Alamos Neutron Scattering Center where neutrons are produced using 800 MeV proton induced spallation reactions on heavy element production targets. Using the pulsed high neutron fluence available at this facility combined with time of flight techniques it will be possible to make neutron capture measurements in the neutron energy range from eV to 100’s of keV on rare and radioactive target material at the milligram and below level. These measurements will provide critically needed data for the interpretation of the astrophysical s-process “branching point” nuclei as well as information for reactions needed in understanding transmutation processes of radioactive species.

Neutron capture nucleosynthesis, which is producing essentially all elements between Fe and the actinides, takes place in the He burning zones of evolved stars (sprocess) and presumably in supemovae (rprocess). The slow time scale of stellar burning scenarios implies that the associated neutron capture path follows the stability valley and that the resulting abundances are to good approximation inversely proportional to the respective (n,γ) cross sections. The experimental program at the Karlsruhe Van de Graaff accelerator, which is focused on this field, includes time-of-flight measurements with a 4πBaF2array, activations in a quasi-stellar neutron spectrum, and complementing studies of important α-induced reactions. Recent examples will be presented for each of these areas to illustrate the actual status as well as the need for further efforts. The consequences of these laboratory results for deriving constraints on the physical parameters of the He burning zones are discussed at the example of the stellar neutron flux.

With spherical counteranions such as chloride or hexafluorophosphate, the glycine-derived guanidiniocarbonyl pyrrole cation 1 self-assembles into discrete dimers in DMSO, as can be seen by NMR and ESI mass spectral analysis. According to concentration- and temperature-dependent NMR studies, the dimerization is endothermic and therefore entropy driven. Molecular modeling suggests that the dimers are held together by hydrogen bonding in combination with π−π interactions. In the presence of picrate anions, dimerization of cation 1 does not occur, probably due to the formation of π-stacked ion pairs.

Abstract:  We determined chitinase activity in leaves of four myrmecophytic and four non-myrmecophytic leguminous species at the plants' natural growing sites in Mexico. Myrmecophytic plants (or 'ant plants') have obligate mutualisms with ants protecting them against herbivores and pathogenic fungi. Plant chitinases can be considered a reliable measure of plant resistance to pathogenic fungi. The myrmecophytic Acacia species, which were colonised by mutualistic ants, exhibited at least six-fold lower levels of chitinase activity compared with the non-myrmecophytic Acacia farnesiana and three other non-myrmecophytes. Though belonging to different phylogenetic groups, the myrmecophytic Acacia species formed one distinct group in the data set, which was clearly separated from the non-myrmecophytic species. These findings allowed for comparison between two recent hypotheses that attempt to explain low chitinase activity in ant plants. Most probably, chitinases are reduced in myrmecophytic plant species because these are effectively defended indirectly due to their symbiosis with mutualistic ants.

Stationary modes of the incompressible Stokes equation are derived using the method of potentials. Their relation to instationary modes is discussed.

This paper examines the post-buckling deformations of cylindrical shells conveying viscous fluid. The wall deformation is modelled using geometrically nonlinear shell theory, and lubrication theory is used to model the fluid flow. The coupled fluid-solid problem is solved using a parallelized FEM technique. It is found that the fluid-solid interaction leads to a violent collapse of the tube such that immediate opposite-wall contact occurs after the buckling if the volume flux is kept constant during buckling. If the pressure drop through the tube is kept constant during the buckling, the fluid-solid coupling slows down the collapse (compared to buckling under a dead load). The effects of various parameters (upstream pressure, axial pre-stretch and the geometry of the tube) on the post-buckling behaviour are examined and the exact geometrically nonlinear shell theory is compared to Sanders’ (1963) moderate rotation theory. Finally, the implications of the results for previous models which described the wall deformation using so called “tube laws” are discussed.

This paper examines the stability of cylindrical shells conveying viscous flow. Geometrically nonlinear Lagrangian shell theory is used to describe the deformation of the tube wall. The fluid flow is modelled using lubrication theory. The coupled fluid-solid problem is discretized with finite differences and the critical parameter combinations (upstream pressure and volume flux) for which the tube buckles are examined. The most unstable circumferential buckling wavenumber and the buckling modes are determined for an experimental procedure in which the upstream pressure is held at a constant value while the volume flux is increased until buckling occurs. Finally, the effect of variations in the tube geometry and the effects of the axial pre-stretch are examined.

An inhibitor isolated from the serum-free culture medium of human myeloid leukemic HL-60 cells was able to suppress mitogen- and alloantigen-stimulated proliferative responses of normal lymphocytes in a dose-dependent manner. In vitro production, concentration, and purification by column chromatography and electrophoresis revealed that the inhibitor was produced constitutively, required RNA synthesis, and had a molecular weight in the range of 40,000-60,000. The inhibitor was also produced in vitro by myeloid leukemia cells isolated from patients with acute myelogenous leukemia. In a similar manner, the inhibitory material suppressed proliferative responses of allogeneic and autologous lymphocytes. Suppression was accompanied by drastically reduced production of interleukin 2 and lymphokines, which regulate differentiation of myeloid leukemia cells, and suppression was reversed by addition of exogenous interleukin 2. The inhibitor did not suppress clonogenic proliferation of normal granulocytes and macrophages suggesting that inhibition of production or interference with interleukin 2 activity as a possible mechanism. These interactions between leukemia cells and lymphocytes have shed new light on the immunosuppression and growth advantage of leukemia cells. Inhibitory activity of HL-60 cells was diminished after they were induced to differentiate, indicating that differentiation induced by lymphokines may be an effective means of controlling leukemia.

Summary In the past years the cultivation of maize in the Federal Republic of Germany has been intensified, and with the processing of localy bred maize a production of maize germ oil from German varieties could be expected.

Summary Investigations were conducted on the composition of fatty acids in the fat of the embryo, the endosperm and several crush fractions of the maize kernel.

The availability of zinc from isolated casein (CasD) was compared with that from whey protein (WpD) in 23–25 day old rats. The study was designed to show the course of the gastrointestinal transit time of either chyme (radiolabeled by141Ce as a non-absorbable marker) or zinc (as65Zn) in groups of 9 to 12 animals each. Animals were killed either 1/4, 1/2, 1, 2, 6, 12 or 24 hours after intragastric intubation of the protein suspensions. Immediately afterwards, intragastric pH was measured and the determination of zinc retention in intestinal tissues and liver as well as in the carcass was performed. 30 and 60 minutes after intubation the intragastric pH of the CasD group was significantly lower than that of the WpD group. The precipitation behaviour of the two protein fractions — compact curd formation by the CasD versus flocculent structure of the WpD — was determining for the pattern of gastric emptying. With the WpD the chyme was emptied according to an exponential function; while the CasD precipitate left the stomach in three distinct phases. With either protein suspension zinc left the stomach earlier than the bulk of the chyme, indicating a partial disintegration of the zinc-protein-complexes. With the WpD, zinc was emptied exponentially, whereas with the CasD a biphasic emptying pattern was found. Ileum was found to be the main zinc absorbing segment, mainly due to the long time of contact with zinc. After 2 and 12 hours zinc retention from the CasD was significantly higher than that from the WpD, however, after 24 hours retention was significantly better from the WpD. From the present study it can be concluded that, for comparison of zinc availability from diets containing different proteins, short-term experiments are not appropriate. Furthermore, it can be supposed that preabsorptive processes in the stomach are crucial for the availability of zinc. Ziel der an 23 bis 25 Tage alten Ratten durchgeführten Untersuchungen war es, die Verfügbarkeit von Zink aus intragastral verabreichten Casein-(CasD-) bzw. Molkenprotein-(WpD-)Suspensionen zu vergleichen. Um den zeitabhängigen Verlauf des gastrointestinalen Durchgangs des Chymus (mit nichtresorbierbarem141Ce markiert) und des Zinks (als65Zn) zu ermitteln, wurden je 9 bis 12 Tiere 1/4, 1/2, 1, 2, 6, 12 und 24 Stunden nach dem Sonden getötet. Unmittelbar danach wurde der intragastrale pH-Wert sowie die Retention von Zink im Darmgewebe, Leber und Restkörper gemessen. 30 Minuten nach Intubation der Proteine war der pH-Wert im Magen der CasD-Gruppe signifikant niedriger als der der WpD-Gruppe. Die unterschiedliche intragastrale Präzipitation der beiden Proteine — kompaktes Präzipitat bei Casein, feinflockiges bei Molkenprotein — dürfte ausschlaggebend sein für das Entleerungsmuster aus dem Magen: der Chymus aus WpD wurde einer Exponentialfunktion entsprechend entleert, während der Chymus aus CasD den Magen in drei Phasen mit unterschiedlicher Geschwindigkeit verließ. Das Zink aus beiden Proteinsuspensionen wurde schneller aus dem Magen entleert als die Masse des Chymus, woraus auf eine zumindest partielle Loslösung des Zinks aus der Proteinbindung geschlossen werden kann. Das Zink aus der WpD wurde exponentiell, das Zink aus der CasD nach einem biphasischen Muster entleert. Als Folge der besonders langen Verweildauer des Zinks im Ileum erwies sich dieser Darmabschnitt als Hauptresorptionsort. Die Zink-Retention war 2 und 12 Stunden nach Verabreichung der Nahrungen signifikant höher aus der CasD als aus der WpD, nach 24 Stunden jedoch war aus der WpD signifikant mehr Zink retiniert worden als aus der CasD. Aus dieser Untersuchung ist zu folgern, daß zur Beurteilung der Zink-Verfügbarkeit aus unterschiedlichen Proteinen Kurzzeitversuche ungeeignet sind. Weiterhin muß angenommen werden, daß die präresorptiven Prozesse im Magen für die Zinkverfügbarkeit von wesentlicher Bedeutung sind.

The efficacy and safety of lifibrol, a novel cholesterol-lowering drug, was investigated in a double-blind clinical study in 168 patients with primary hypercholesterolaemia. Placebo and four lifibrol dose groups (150, 300, 450 and 600 mg/day) were tested over a period of 4 weeks.

Large axisymmetric deformations of collapsible tubes conveying a viscous flow are examined. Geometrically nonlinear Lagrangian shell theory is used to describe the deformation of the tube. The fluid flow is modelled using lubrication theory. The coupled fluid-solid problem is solved numerically using an FEM technique. In order to explain the mechanisms involved in the tube deformation, the effects of bending stiffness, wall shear stress and axial pre-stretch are examined in detail. The dependence of the tube resistance on the volume flux is investigated for two different experimental set-ups (constant pressure at either upstream or downstream end of the collapsible tube). Finally, the exact nonlinear shell theory used in this paper is compared to Sanders' moderate rotation theory and an improvement to his theory is suggested.