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Zusammenfassung: Mit dem Begriff der individualisierten Medizin werden neuere Ansätze zur positiven Beeinflussung des Krankheitsverlaufs oder zur Primärprävention bezeichnet, die auf die individuelle genetische Disposition von Patienten zugeschnittenen therapeutischen, präventiven und rehabilitativen Interventionen beruhen. Neu entwickelte Technologien, etwa die Genotypisierung von Mutationen und Metaboliten, bieten die Möglichkeit einer auf das Individuum maßgeschneiderten medizinischen Versorgung. In diesem Beitrag werden angebots- und nachfrageseitige Herausforderungen sowohl für die Gesundheitswirtschaft als auch für die Gesundheitsversorgung und deren zukünftige Finanzierung durch diese Entwicklung diskutiert. Individualisierte Medizin wird tendenziell zu höheren Gesamtkosten auf Systemebene führen, was nur unter der Voraussetzung entsprechend nachweisbaren Nutzengewinns akzeptiert werden wird. Daher sind generalisierende Aussagen weder für die Gesamtkosten noch für die Erstattungsfähigkeit von Leistungen der individualisierten Medizin möglich, sondern diese sind in jedem Einzelfall auf ihre Kosten- und Nutzeneffekte hin zu beurteilen. Abschließend wird auf die Notwendigkeit einer hinreichenden Informationsbasis auf beiden Marktseiten sowie einer ausreichenden Risikobereitschaft, bisherige Behandlungsmuster und Organisationsformen ständig zu überprüfen, hingewiesen.

Nuclear reactions leading to formation of new superheavy elements and isotopes are discussed. The scope and limitations of different nuclear reactions ("cold" and "hot" synthesis, fusion of fission fragments, transfer reactions and reactions with radioactive ion beams) are analyzed, trying to find most promising reactions which may be used at available facilities.

Within a thermal model we estimate possible multiplicities of scalar glueballs in central Au+Au collisions at AGS, SPS, RHIC and LHC energies. For the glueball mass in the region 1.5-1.7 GeV, the model predicts on average (per event) 0.5-1.5 glueballs at RHIC and 1.5-4 glueballs at LHC energies. Possible enhancement mechanisms are discussed.

Within the mean-field approximation to the Lagrangian field theory, we study the effects of isovector-scalar meson δ on nucleon effective masses and the equation of state (EOS) of neutron-star matter in strong magnetic fields. We find that the δ-field leads to a large splitting of proton and neutron effective masses in neutron-star matter. The strength of the δ-field decreases, however, with the increase of the magnetic field and is near zero at ultrastrong field. Although the proton effective mass is found to be highly influenced by magnetic fields, the effect of magnetic fields on the neutron effective mass is negligible. The EOS of neutron-star matter turns out to be stiffer at B < 1015 G but becomes softer at stronger magnetic field after including the δ-field. The effect due to the anomalous magnetic moments of both nucleons and lepton is also studied and is found to be appreciable only at ultrastrong magnetic field (B > 1019 G). In the range of 1015–1018 G, the properties of neutron-star matter remain similar to those without magnetic fields.

Properties of a hypothetical scalar baryonium with the quark content

Dissociation and fission of small neutral, singly and doubly charged strontium clusters are studied by means of ab initio density functional theory methods and high-resolution time-of-flight mass spectrometry. Magic numbers for small strontium clusters possessing enhanced stability towards monomer evaporation and fission are determined. It is shown that ionization of small strontium clusters results in the alteration of the magic numbers. Thermal promotion of Coulombic fission for the Sr²⁺₇ cluster is predicted.

We predict strong enhancement in the photoabsorption of small Mg clusters in the region of 4–5 eV due to the resonant excitation of the plasmon oscillations of cluster electrons. Photoabsorption spectra for neutral Mg clusters consisting of up to N = 11 atoms have been calculated using an ab initio framework based on the time-dependent density functional theory (TDDFT). The nature of predicted resonances has been elucidated by comparison of the results of the an ab initio calculations with the results of the classical Mie theory. The splitting of the plasmon resonances caused by the cluster deformation is analysed. The reliability of the calculation scheme used has been proved by performing the test calculation for a number of sodium clusters and the comparison of the results obtained with the results of other methods and experiment.

Results of molecular dynamics simulations of fission reactions

Based on the cold valley description of cold fission and fusion we investigate the cluster radioactivity phenomenon for the N &equal; Z nucleus 114Ba, in the region of actinide nuclei and for some newly discovered superheavy nuclei. Using ground-state deformations of fragments as predicted by the macroscopic–microscopic model and taking the optimal orientation at scission, the pole–pole one, we obtain minima in the driving potential which are confirming the observed clusterization for mother nuclei with Z between 88 and 94 in majority of cases. Based on this we predict new cases of clusterization for nuclei up to Z &equal; 100.

A recently published experimental dependence of the J/ψ to Drell–Yan ratio on the measured, by a zero degree calorimeter, forward energy EZDC in Pb + Pb collisions at the CERN SPS is analysed. Using a model-independent approach it is shown that the data are at variance with an earlier published experimental dependence of the same quantity on the transverse energy of neutral hadrons ET. The discrepancy is related to a moderate centrality region: 100 ≲ Np ≲ 200 (Np is the number of participant nucleons) and is peculiar only to the data obtained within the &lquot;minimum bias&rquot; analysis (using the &lquot;theoretical Drell–Yan&rquot;). This could result from systematic experimental errors in the minimum bias sample. A possible source of the errors is discussed.

We calculate the sequential decays a₁ &rightarrow; πσ &rightarrow; 3π and a₁ &rightarrow; πρ &rightarrow; 3π using chiral SU(2) ⊗ SU(2) current commutation relations. Proper vertices a₁πσ, σππ, a₁πρ, ρππ are derived from Ward identities and yield energy-dependent decay widths Γ_{ρ&rightarrow;ππ} and Γ_{σ&rightarrow;ππ} necessary for the total Γ_{a1&rightarrow;3π}

We give a quantum description of the ternary cold fission process within a stationary scattering formalism. The dynamics of the light particle and heavy fragments is described by a self-consistent system of equations for radial wavefunctions. We consider the spontaneous cold ternary fission of ²⁵²Cf accompanied by ⁴He and ¹⁰Be. The light cluster decays from some resonant eigenstate in the Coulomb plus nuclear potential. It turns out that for the angular momentum projection K &equal; 0 the light cluster emission is concentrated in the polar direction. By increasing K the maximum of the angular distribution moves towards the equator, as measured in the experiment. For ⁴He we predict short living decaying states. Due to a large repulsive core, proportional to K², such states are hindered in the case of ¹⁰Be. The motion of the two heavy fragments with −K compensates the rotation of the light fragment. We call this collective motion tri-rotor mode and it should be detected in the fragment yields by magnetic transitions.

The dependence of the driving potential on the orientation of fragments at scission is investigated for the case of cold fission of ²⁵²Cf. It is shown that in the case of cold fission the fragments exclusively emerge at scission in the pole–pole configuration. However, quantum fluctuations enable small deviations from this configuration during the tunnelling process. The mass yields of fission fragment pairs in the cold fission of ²⁵²Cf are computed for pole–pole and equator–equator orientations and are compared to the experimental data.

With new high statistic data, new isotopes and new high-spin structures are observed in neutron-rich nuclei populated in the spontaneous fission of 252Cf. The 135Te levels are extended, and many new levels in 139,141Ba observed. The coexistence of collective and single particle-hole states is found in 135Te. The N= 83 135Te and 139Ba show marked differences associated with differences in their particle and hole states. New levels in 141Ba complete evidence for two opposite-parity doublets characteristic of stable octupole deformation. In 114,116Pd a second backbend is observed for the first time in this mass region and the backbend in 118Pd occurs earlier than in 112-116Pd because of a reduction in pairing. Gamma-type vibrational bands are seen up to 13+to 15+in 104,106Mo, 108-112Ru, and 112-116Pd. Their behavior reflects prolate to triaxial shapes in these nuclei. The levels of 162,164Gd are observed for the first time. As Nincreases toward mid-shell at 104, the moments of inertia in N= 100 164Gd show an unexpected decrease compared to N= 98 162Gd. The levels in 162,164Gd form remarkable shifted identical bands with nuclei separated by 2n, 2p, α, and 2α.

We consider the production of the open charm and J/ψ mesons in heavy-ion collisions at BNL RHIC. We discuss several recently developed pictures for J/ψ production and argue that a measurement at RHIC energies is crucial for disentangling these different descriptions.

The dependence of the J/ψ yield on the transverse energy E_T in heavy ion collisions is considered within the statistical c&barc; coalescence model. The model fits the NA50 data for Pb+Pb collisions at the CERN SPS even in the high-E_T region (E_T &gtrsim; 100 GeV). Here E_T fluctuations and E_T losses in the dimuon event sample naturally create the celebrated drop in the J/ψ to Drell–Yan ratio.

We give a description of the binary cold fission process of ²⁵²Cf within the stationary scattering formalism. The decay of the dinuclear system (quasi-molecule) consists in the tunnelling of a metastable state from an internal region, where the nucleus–nucleus potential makes a quasi-molecular pocket due to the interplay of repulsive and attractive nuclear forces and the Coulomb force, to the asymptotic region which is governed solely by the Coulomb repulsion. As a transverse internal motion, we suppose angular oscillations of the fragments up to the scission point. In the external region these vibrations transform into rotations. The nuclear interaction is given by a double-folding procedure using M3Y forces plus a repulsive contact potential. For the experimental Q-value we find several resonant states of the binary system, depending on the repulsive strength. We predict a strong dependence of decay widths upon the internal structure of the considered resonant state. Therefore the measured yields of the two fragments with given angular momenta in coincidence are able to provide more insight into the internal molecular dynamics of the decaying dinuclear system.

We consider J/ψproduction in heavy ion collisions at RHIC energies in the statistical coalescence model with exact (canonical ensemble) charm conservation. Charm quark–antiquark pairs are assumed to be created in primary hard parton collisions, but open and hidden charm particles are formed at the hadronization stage according to the laws of statistical mechanics. The dependence of the J/ψproduction on both the number of nucleon participants and the collision energy is studied. The model predicts J/ψsuppressionfor low energies, whereas at the highest RHIC energy the model reveals J/ψenhancement.

We derive the equation of state (EOS) for electrically charged neutral dense matter using the quantum hadrodynamics (QHD) model. This is carried out in a non-perturbative manner including quantum corrections for baryons through a realignment of vacuum with baryon–antibaryon condensates. This yields the results of relativistic Hartree approximation of summing over baryonic tadpole diagrams. The quantum corrections from the scalar meson is also taken into account in a similar way. This leads to a softening of the EOS for the hyperonic matter. The formalism also allows us to make a self-consistent calculation of the in-medium sigma meson mass. The effects of such quantum corrections on the composition of charged neutral dense matter is considered. The effect of the resulting EOS on the structure of neutron stars is also studied.

We argue that the color deconfinement in heavy ion collisions may lead to enhanced production of hadrons with open heavy flavor (charm or bottom). We estimate the upper bound of this enhancement.

We investigate various properties of neutron star matter within an effective chiral SU(3)L× SU(3)Rmodel. The predictions of this model are compared with a Walecka-type model. It is demonstrated that the importance of hyperon degrees depends strongly on the interaction used, even if the equation of state near saturation density is nearly the same in both models. While the Walecka-type model predicts a neutron star core with strangeness fraction fS? , the chiral model allows only for fS? and predicts that ?0, ?+, and ?0will not exist in stars, in contrast to the Walecka-type model.

Abstract: We investigate the excitation function of quark-gluon plasma formation and of directed in-plane flow of nucleons in the energy range of the BNL-AGS and for the E Labkin = 40AGeV Pb + Pb collisions performed recently at the CERN-SPS. We employ the three-fluid model with dynamical unification of kinetically equilibrated fluid elements. Within our model with first-order phase transition at high density, droplets of QGP coexisting with hadronic matter are produced already at BNL-AGS energies, E Labkin ≃ 10AGeV. A substantial decrease of the isentropic velocity of sound, however, requires higher energies, E Labkin ≃ 0AGeV. We show the effect on the flow of nucleons in the reaction plane. According to our model calculations, kinematic requirements and EoS effects work hand-in-hand at E Labkin = 40AGeV to allow the observation of the dropping velocity of sound via an increase of the directed flow around midrapidity as compared to top BNL-AGS energy.

Zusammenfassung: □ Finanzielle Restriktionen und eine stärkere Ergebnisorientierung erfordern mehr und mehr rationale Entscheidungen über den Mitteleinsatz im Gesundheitswesen. Solche Entscheidungen sind Gegenstand medizinischer, ethischer und wirtschaftlicher Erwägungen. Die Steuerung des Gesundheitswesens bedarf sowohl auf gesamtwirtschaftlicher Ebene der medizinischen und wirtschaftlichen Orientierung als auch bei der Auswahl von geeigneten Versorgungsformen in Klinik und Praxis. Die evaluative Gesundheitsökonomie kann dabei ein wichtiges Hilfsmittel zur Entscheidungsfindung sein. □ Damit die Ergebnisse von gesundheitsökonomischen Evaluationsstudien valide interpretiert werden können, ist ein Mindestmaß an gemeinsamer Methodik und ausreichender Transparenz erforderlich. Zu diesem Zweck wurden Empfehlungen entwickelt. Sie sollen einerseits Standards vermitteln, andererseits den methodischen Fortschritt und die wissenschaftliche Freiheit in der Gesundheitsökonomie nicht unnötig einengen. □ Für die Zukunft ist eine ständige Weiterentwicklung der Empfehlungen und ihre Anpassung an den jeweiligen Stand der gesundheitsökonomischen Forschung anzustreben.

The hypothesis of local equilibrium (LE) in relativistic heavy ion collisions at energies from AGS to RHIC is checked in the microscopic transport model. We find that kinetic, thermal, and chemical equilibration of the expanding hadronic matter is nearly reached in central collisions at AGS energy for t ≥ 10 fm/ c in a central cell. At these times the equation of state may be approximated by a simple dependence P ≅ (0.12 − 0.15) ε. Increasing deviations of the yields and the energy spectra of hadrons from statistical model values are observed for increasing bombarding energies. The origin of these deviations is traced to the irreversible multiparticle decays of strings and many-body ( N ≥ 3) decays of resonances. The violations of LE indicate that the matter in the cell reaches a steady state instead of idealized equilibrium. The entropy density in the cell is only about 6% smaller than that of the equilibrium state.

The modification of the width of the rho meson due to in-medium decays and collisions is evaluated. In high temperature and/or high density hadronic matter, the collision width is much larger than the one-loop decay width. The large width of the ρ meson in matter seems to be consistent with some current interpretations of the e e mass spectra measured at the CERN/SPS.

Freeze out of particles across three dimensional space-time hypersurface is discussed in a simple kinetic model. The final momentum distribution of qemitted particles, for freeze out surfaces with space-like normal, shows a non-exponential transverse momentum spectrum. The slope parameter of the ptdistribution increases with increasing pt, in agreement with recently measured SPS pion and h−spectra.

We present the thermodynamically consistent procedure to introduce the excluded volume effect into the equation of state of nuclear matter. Implications are discussed in the framework of a mean-field model for hadrons with eigenvolume.

We consider the influence of the bulk properties of nuclear matter, namely the ground state incompressibility and the effective nucleon mass, and of the MIT bag constant on the phase transition from hadron matter to quark gluon plasma. It is mainly the effective nucleon mass which determines the stiffness of the equation of state and therefore also the behaviour of the phase transition curves. The energy densities in the coexistence region are found to increase for finite chemical potentials and softer equations of state up to 10 GeV/fm3. For small bag constants and for softer nuclear equations of state the phase boundary exhibits unusual deformations, due to the fact that the phase transition sets in already at pressures not too far from the saturation value. Although this would increase the experimental possibility to create the QGP, it is more likely that one must regard bag constants in the range of the original MIT value as not producing a realistic behaviour of the quark-hadron matter phase transition in the context of an MIT bag equation of state for the quark side.

Hadron production in soft hadronic collisions is successfully described by a longitudinal excitation and subsequent decay of color flux tubes. We consider the dynamics of interacting unstable strings as a generalization designed forhA andAA interactions at ultrarelativistic energies. The constituent quarks at the ends of the decaying strings and the produced hadrons can interact with the surrounding matter. The effect of secondary interactions in molecular dynamics calculations forAA collisions at CERN energies (200A GeV) can be seen in an enhancement of transverse energy, particle production and the mean transverse momenta. The results agree very well with the experimental measurements at ultrarelativistic beam energies inpp, hA and the recentAA collisions.

We investigate the reaction O+Au at 200 AGeV in an ideal relativistic (3+1)-dimensional one-fluid hydrodynamical model. We correct former calculations which contained acausal matter transport, leading to contradictions with experimental data for the baryonic rapidity distribution. We find that the corrected results are in good agreement with data, casting new light on the question of the applicability of ideal one-fluid hydrodynamics to heavy-ion collisions.

Enhanced yields of lambdas and other strange hadrons in experiments on nuclear targets at incident energies of 200 GeV have been recently reported by several experimental groups. We calculated events for proton projectiles on different targets in the framework of the relativistic quantum molecular dynamics approach which is based on string excitation and fragmentation with subsequent hadronic collisions. Here we address the question whether the experimentally found lambda enhancement in hadron-nucleus collisions can be understood by interactions of secondary hadrons formed in the target nucleus. Our results for ?'s, kaons and agree well with the experimental measurements. We find a doubling of lambda production in the target fragmentation region forp collisions on heavy targets due to nuclear cascading of the produced mesons. Resonances play an important role in creating strange quark pairs confirming earlier findings of their outstanding role inAA collisions.

3+1 dimensional relativistic calculations of the space-time evolution of heavy ion collisions at bombarding energies from 5 to 200 GeV/n are presented. Collisions with heavier projectiles seem to be more rewarding to form extended regimes of highly excited nuclear matter containing enough baryons for a sufficient time span to enable a transition of the hadron matter into a quark gluon plasma. A strong impact parameter dependence has to be taken into account when comparing the final baryon rapidity distributions with experimental results. Experimental results of the reactions16O(60, 200 GeV/n)?Pb are compared with hydrodynamical calculations.

An improved two-center model has been used to describe the elastic scattering potentials for the collision of identical nuclei. The macroscopic-microscopic approach includes liquid drop (LD) deformation energies, shell corrections and pairing energy corrections. As basis for the microscopic part a two-center shell model has been used with a Hamiltonian including a Thomas-type spin-orbit potential and an l2 correction term. The model is applied to the sudden and adiabatic type of scattering process, including a compression energy term in the LD part for the former case. Results are given as potential energy surfaces for the adiabatic scattering process and potential energy curves for the sudden scattering process.