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The borosilicate 0106-B1-bioactive glass (BG) composition (in wt%: 37.5 SiO2, 22.6 CaO, 5.9 Na2O, 4.0P2O5, 12.0 K2O, 5.5 MgO, 12.5 B2O3) has shown favorable processing characteristics and bone regeneration ability. This study investigated the addition of zinc (Zn) to 0106-B1-BG as an approach to improve this BG's biological properties. Different proportions of ZnO were substituted for CaO in 0106-B1-BG, resulting in three new BG-compositions: 1-Zn-BG, 2-Zn-BG, 3-Zn-BG (in wt%: 37.5 SiO2, 21.6/20.1/17.6 CaO, 4.0 P2O5, 5.9 Na2O, 12.0 K2O, 5.5 MgO, 12.5 B2O3and 1.0/2.5/5.0 ZnO). Effects of the BG compositions on cytocompatibility, osteogenic differentiation, extracellular matrix deposition, and angiogenic response of human bone marrow-derived mesenchymal stromal cells (BMSCs) were evaluated in vitro. Angiogenic effects were assessed using a tube formation assay containing human umbilical vein endothelial cells. The in vivoosteogenic and angiogenic potentials of 3-Zn-BG were investigated in comparison to the Zn-free 0106-B1-BG in a rodent critical-size femoral defect model. The osteogenic differentiation of BMSCs improved in the presence of Zn. 3-Zn-BG showed enhanced angiogenic potential, as confirmed by the tube formation assay. While Zn-doped BGs showed clearly superior biological properties in vitro, 3-Zn-BG and 0106-B1-BG equally promoted the formation of new bone in vivo; however, 3-Zn-BG reduced osteoclastic cells and vascular structures in vivo. The acquired data suggests that the differences regarding the in vivoand in vitroresults may be due to modulation of inflammatory responses by Zn, as described in the literature. The inflammatory effect should be investigated further to promote clinical applications of Zn-doped BGs.

Die Hüftdysplasie ist eine der häufigsten Erkrankungen der Hüfte im Kindesalter. Oft bleibt die Fehlstellung asymptomatisch bis ins Erwachsenenalter, jedoch gilt sie als Präarthrose und stellt einen der Hauptgründe für eine vorzeitige Koxarthrose dar. Die Deformität betrifft das Acetabulum, kann jedoch auch mit Formveränderungen am proximalen Femur einhergehen. Reicht die konservative Therapie bei milder Dysplasie nicht aus oder besteht eine mittelschwere bis schwere Dysplasie, sollte ggf. eine operative Therapie beispielsweise durch Umstellungen am Becken und/oder am Femur sowie ggf. zusätzlich durch Hüftgelenkarthroskopie erfolgen, um die Präarthrose zu beseitigen und eine vorzeitige Koxarthrose zu verhindern. Im Rahmen dieses Manuskripts werden die Deformität, die notwendige Diagnostik zur Diagnosestellung und die Behandlungen zur Verhinderung einer Arthrose erläutert.

Der Schiefhals ist eine häufige Pathologie beim neugeborenen und älteren Kind. Die Differenzialdiagnosen unterscheiden sich stark in Schwere, der Möglichkeit von Spätfolgen und ihrer Behandlung. Der Artikel gibt einen Überblick über die Differenzialdiagnostik des Schiefhalses beim Kind, die aktuelle Literatur sowie einen Einblick in unseren diagnostischen und therapeutischen Algorithmus. Man unterscheidet angeborene von erworbenen und schmerzhafte von nichtschmerzhaften Schiefhaltungen. In der Regel handelt es sich um einen kongenitalen muskulären Schiefhals, mit einer geschätzten Inzidenz von 0,3–1,9 %. Die wichtigste Differenzialdiagnose des angeborenen muskulären Schiefhalses ist das Klippel-Feil-Syndrom. Erworbene Schiefhaltungen haben zum Teil schwerer wiegende Ursachen und sollten immer abgeklärt werden. Die Kenntnis der möglichen Ursachen und ihrer Behandlung ist essenziell, um dem betroffenen Kind und seiner Familie adäquat helfen zu können und etwaige Spätfolgen zu verhindern. Torticollis is a common neck deformity in both newborn and older children. The various causes of the abnormal posturing of the head differ in severity, long-term consequences and their treatment. This article gives an overview of the differential diagnoses of torticollis in children and current literature, and provides insight into our diagnostic and therapeutic algorithm. A distinction is drawn between congenital and acquired deformities and whether or not they are painful. Most commonly, children present with a congenital muscular torticollis, which has an estimated incidence of 0.3 to 1.9%. The main differential diagnosis of congenital muscular torticollis is Klippel-Feil syndrome. Acquired torticollis often has more severe causes and always needs a thorough diagnostic clarification. The knowledge of possible causes and their treatment is essential to provide adequate care for affected children and their families and to prevent long-term consequences.

The 45S5-bioactive glass (BG) composition is the most commonly investigated amongst BG-based bone substitutes. By changing BG compositions and by addition of therapeutically active ions such as boron, the biological features of BGs can be tailored towards specific needs and possible drawbacks can be overcome. The borosilicate glass 0106-B1 (composition in wt%: 37.5 SiO2, 22.6 CaO, 5.9 Na2O, 4.0 P2O5, 12.0 K2O, 5.5 MgO, 12.5 B2O3) has demonstrated pro-angiogenic properties. However, the osteogenic performance of the 0106-B1-BG and its influence on cell viability and proliferation in vitroas well as its osteogenic and angiogenic properties in vivohave not been investigated. Therefore, in this study, the impact of 0106-B1-BG and 45S5-BG on osteogenic differentiation, viability and proliferation on human mesenchymal stromal cells (MSCs) was assessed in vitro. Furthermore, MSC-seeded scaffolds made from both BG types were implanted subcutaneously in immunodeficient mice for 10 weeks. Osteoid formation was quantified by histomorphometry, vascularization was visualized by immunohistological staining. Additionally, the in vivoexpression patterns of genes correlating with osteogenesis and angiogenesis were analyzed. In vitro, the impact of 45S5-BG and 0106-B1-BG on the proliferation, viability and osteogenic differentiation of MSCs was comparable. In vivo, scaffolds made from 0106-B1-BG significantly outperformed the 45S5-BG-based scaffolds regarding the amount and maturation of the osteoid. Furthermore, 0106-B1-BG-based scaffolds showed significantly increased angiogenic gene expression patterns. In conclusion, the beneficial angiogenic properties of 0106-B1-BG result in improved osteogenic properties in vivo, making the 0106-B1-BG a promising candidate for further investigation, e.g.in a bone defect model.

Particle and photon polarization phenomena occurring in collisions of relativistic ions with matter have recently attracted particular interest. Investigations of the emitted characteristic x-ray and radiative electron capture radiation has been found to be a versatile tool for probing our present understanding of the dynamics of particles in extreme electromagnetic fields. Owing to the progress in x-ray detector technology, in addition, accurate measurements of the linear polarization for hard x-ray photons as well as the determination of the polarization plane became possible. This new diagnostic tool enables one today to derive information about the polarization of the ion beams from the photon polarization features of the radiative electron capture process.

The two-photon 2E1 transition from the singlet 2s state of heliumlike tin was measured. An alternative experimental approach was adopted in the present investigation where the two-photon emission results from the decay of the 2s state by selective K-shell ionization of Li-like tin ions in relativistic collisions with a low-Z gaseous target, which allowed for a measurement of the undistorted two-photon spectral shape. The measured 2E1 energy distribution was compared with fully relativistic calculations, which predict a Z dependence of the distribution. The preliminaryresults indicate the best agreement with the relativistic many body calculations for tin, and thus confirm the sensitivity on Z. Detailed data analysis is still in progress.

We report the results of the x-ray radiative recombination (RR) experiment at the electron cooler of the ESR storage ring performed, for the first time, for detuned (off-cooling) electron energies. In this experiment the recombination of stored, decelerated bare uranium ions with electrons in the energy range 0–1000 meV was studied by observing K-RR x-ray photons emitted from direct radiative recombination to the lowest n=1 state. In this way the RR process was studied in a state selective manner for several off-cooling electron energies. The measured dependency of the recombination rate on the relative electron energies for K-shell RR x-ray photons are compared with the predictions of both nonrelativistic and fully relativistic calculations for the radiative recombination. A role of the relativistic effects, which contribute substantially for higher relative electron energies, are discussed. Strong enhancement of the recombination rate is observed for the the zero relative electron energy (cooling condition) for the K-shell.

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.

Abstract: 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.

The two-photon 2E1 transition from the singlet 2s state of heliumlike tin was measured. An alternative experimental approach was adopted in the present investigation where the two-photon emission results from the decay of the 2s state by selective K-shell ionization of Li-like tin ions in relativistic collisions with a low-Z gaseous target, which allowed for a measurement of the undistorted two-photon spectral shape. The measured 2E1 energy distribution was compared with fully relativistic calculations, which predict a Z dependence of the distribution. The preliminary results indicate the best agreement with the relativistic many body calculations for tin, and thus confirm the sensitivity on Z. Detailed data analysis is still in progress.

We report the results of the x-ray radiative recombination (RR) experiment at the electron cooler of the ESR storage ring performed, for the first time, for detuned (off-cooling) electron energies. In this experiment the recombination of stored, decelerated bare uranium ions with electrons in the energy range 0?1000?meV was studied by observing K-RR x-ray photons emitted from direct radiative recombination to the lowest n=1 state. In this way the RR process was studied in a state selective manner for several off-cooling electron energies. The measured dependency of the recombination rate on the relative electron energies for K-shell RR x-ray photons are compared with the predictions of both nonrelativistic and fully relativistic calculations for the radiative recombination. A role of the relativistic effects, which contribute substantially for higher relative electron energies, are discussed. Strong enhancement of the recombination rate is observed for the the zero relative electron energy (cooling condition) for the K-shell.

Particle and photon polarization phenomena occurring in collisions of relativistic ions with matter have recently attracted particular interest. Investigations of the emitted characteristic x-ray and radiative electron capture radiation has been found to be a versatile tool for probing our present understanding of the dynamics of particles in extreme electromagnetic fields. Owing to the progress in x-ray detector technology, in addition, accurate measurements of the linear polarization for hard x-ray photons as well as the determination of the polarization plane became possible. This new diagnostic tool enables one today to derive information about the polarization of the ion beams from the photon polarization features of the radiative electron capture process.

Abstract: Particle and photon polarization phenomena occurring in collisions of relativistic ions with matter have recently attracted particular interest. Investigations of the emitted characteristic x-ray and radiative electron capture radiation has been found to be a versatile tool for probing our present understanding of the dynamics of particles in extreme electromagnetic fields. Owing to the progress in x-ray detector technology, in addition, accurate measurements of the linear polarization for hard x-ray photons as well as the determination of the polarization plane became possible. This new diagnostic tool enables one today to derive information about the polarization of the ion beams from the photon polarization features of the radiative electron capture process.

Abstract: The two-photon 2E1 transition from the singlet 2s state of heliumlike tin was measured. An alternative experimental approach was adopted in the present investigation where the two-photon emission results from the decay of the 2s state by selective K-shell ionization of Li-like tin ions in relativistic collisions with a low-Z gaseous target, which allowed for a measurement of the undistorted two-photon spectral shape. The measured 2E1 energy distribution was compared with fully relativistic calculations, which predict a Z dependence of the distribution. The preliminary results indicate the best agreement with the relativistic many body calculations for tin, and thus confirm the sensitivity on Z. Detailed data analysis is still in progress.

Abstract: We report the results of the x-ray radiative recombination (RR) experiment at the electron cooler of the ESR storage ring performed, for the first time, for detuned (off-cooling) electron energies. In this experiment the recombination of stored, decelerated bare uranium ions with electrons in the energy range 0–1000 meV was studied by observing K-RR x-ray photons emitted from direct radiative recombination to the lowest n=1 state. In this way the RR process was studied in a state selective manner for several off-cooling electron energies. The measured dependency of the recombination rate on the relative electron energies for K-shell RR x-ray photons are compared with the predictions of both nonrelativistic and fully relativistic calculations for the radiative recombination. A role of the relativistic effects, which contribute substantially for higher relative electron energies, are discussed. Strong enhancement of the recombination rate is observed for the the zero relative electron energy (cooling condition) for the K-shell.

Highly differential cross sections have been obtained for dissociative single ionization of H2 by 6 MeV proton impact by measuring the momentum vectors of the electron and the H+ fragment in coincidence. The investigation of the momentum balance of the fragments along the projectile beam provided detailed insight into the four-particle dynamics, even though the H atom is not detected. Within the axial recoil approximation, molecular-frame angular distributions of emitted electrons have been determined for molecules oriented perpendicular to the projectile beam. They are compared with the predictions of a CDW-EIS calculation.

Highly differential cross sections have been obtained for dissociative single ionization of H₂ by 6 MeV proton impact by measuring the momentum vectors of the electron and the H⁺ fragment in coincidence. The investigation of the momentum balance of the fragments along the projectile beam provided detailed insight into the four-particle dynamics, even though the H atom is not detected. Within the axial recoil approximation, molecular-frame angular distributions of emitted electrons have been determined for molecules oriented perpendicular to the projectile beam. They are compared with the predictions of a CDW-EIS calculation.

Highly differential cross sections have been obtained for dissociative single ionization of H2by 6 MeV proton impact by measuring the momentum vectors of the electron and the H+fragment in coincidence. The investigation of the momentum balance of the fragments along the projectile beam provided detailed insight into the four-particle dynamics, even though the H atom is not detected. Within the axial recoil approximation, molecular-frame angular distributions of emitted electrons have been determined for molecules oriented perpendicular to the projectile beam. They are compared with the predictions of a CDW-EIS calculation.

Experimental evidence for intra-atomic double scattering of fast Binary Encounter (BE) electrons produced in collisions of 5.9 MeV/u U29+with various gas targets is presented. A broad distribution of electrons displaying the shape of the (BE) peak at twice of the velocity of the ion beam at angles up to 135° is observed in the double differential electron emission spectra. This emission is attributed to target electrons ejected in a knock-on collision that are subsequently elastically scattered at their own target nuclear potential.

The energy and angular distribution of δ-electrons produced in collisions of swift heavy ions with helium gas targets are presented. Double differential electron emission cross sections d2σ/dEedΩefor different projectiles have been measured as a function of the electron emission energy Eeand the polar electron emission angle ϑe. For systematics the cross sections were investigated for different projectiles from neon up to bismuth at ionic charge states between q=7+ and 24+. The specific projectile energy was kept constant within 10%, i.e. 5.4⩽EP⩽6.0 MeV/u for the different projectiles. The investigations are focussed on the emission cross sections of the Binary Encounter (BE) electrons. The BE electron emission cross section depends strongly on the ionic qas well as on the nuclear charge state ZP. At small emission angles ϑethe electrons are most enhanced but converging towards the q2-scaling at larger angles. An appropriate parameter was found to be the ratio of the ionic charge and the nuclear charge q/ZP. The observation of forward peaked, enhanced electron emission is of great importance for the understanding of radiation damages in dense targets caused by heavy ion collisions.

A new electron spectrograph has been developed to study electron emission in ion–atom collisions and in particular for use in 0° Auger projectile spectroscopy. It incorporates a hemispherical analyser, a 2-dimensional position-sensitive detector (PSD) with multichannel plates and a resistive anode encoder. A novel feature of this analyser is the use of an asymmetric entrance aperture and a non-zero entrance potential to improve focusing by correcting for fringing field effects. A four-element lens mounted at the entrance of the analyser, provides a virtual slit, focusing and decelerating incoming electrons for improved energy resolution and reduction of the ion beam scattering at the spectrometer entrance. The analyser has an acceptance energy range of 20%. As a first test of the apparatus, the production of Binary Encounter electrons from 20 MeV F9+,8++H2collisions was measured. The bare F9+results were used for an in situ calibration of the 2D-PSD overall efficiency. The F8+data were found to be in good agreement with the elastic electron scattering model.

Double differential cross-sections for the production of binary encounter electrons were measured for collisions of 30 MeV bare O8+projectiles with H2, He, Ne, Ar, Kr and Xe targets at an electron ejection angle of θ = 0° with respect to the beam direction. Results were analyzed in terms of the impulse approximation (IA), in which target electrons in the projectile frame undergo 180° Rutherford scattering in the field of the bare projectile ion. Excellent agreement with the data was found for the H2and He targets, while for the multi-electron targets good agreement was established only when target electrons whose velocities were lower than the projectile velocity were included in the calculation.

The velocity of the quasimolecular x-ray emitter is found via Doppler shift measurements. It is in agreement with the center of mass velocity. Applying Doppler shift corrections the intrinsic anisotropy of the quasi-molecularM radiation is determined as a function of x-ray energy for 6 to 45 MeV I bombardment on thin Au targets. Position and amplitude of the maximum anisotropy in the x-ray spectrum depend on impact energy.

The emission probabilities for quasimolecular K-x-radiation (K-MOR) have been measured in208Pb +208Pb collisions at 4.3 MeV/u and 4.8 MeV/u as a function of the scattering angle using the particle-photon-coincidence technique. The probabilities exhibit a superposition of two exponential slopes with different fall-off constants. We identify the sharp fall off at very small impact parameters (<60 fm) with the K-MOR contribution from the decay of 1ss-vacancies. The flatter slope for impact parameters larger than 60 fm is attributed to the radiative decay of holes in 2p1/2s molecular states. In this way, experimental “1ss-MOR-emission probabilities” could be extracted and compared with theory. For 4.3 MeV/u the1ss- and 2p1/2s-excitation probabilities could also be determined and have been compared to coupled-channel calculations and to a scaling law for 1ss excitation.

The 90°-line width ofK x-ray lines induced in heavy ion collisions is mainly determined by the kinematical broadening. Its conversion into mean impact parameters together with total excitation cross section allows to obtain mean excitation probabilities. Within the energy range (1.4–5.9) MeV/u mean excitation probabilities for 2p1/2s-excitation are deduced. Collision systems in theZ-range (150–180) are investigated. A very poor agreement between experiment and theoretical predictions has been found. The excitation probabilities are larger than predicted and are nearly independent of the atomic numberZ of the united atom. The collision energy dependence is much weaker than predicted. Even a decrease of the mean excitation probabilities at high collision energies has been found.

For heavy collision systems withZUA≧100 the excitation mechanism for electrons in molecular orbitals from 2p1/2 1/2 up to 3d3/2 1/2, which end up inK andL levels of the collision partners, is investigated for Iodine projectile velocityv between 1.3 and 3.7 a.u. (i.e. 6.3 MeV≦Ei≦45 MeV). For 2p1/2 1/2 excitation a prevailing radial coupling excitation mechanism is found. In a two state approximation coupling strengths are derived for decisive isolated crossings; for the strong variation of the projectileL x-ray spectra with targetZ and impact velocity a Landau Zener type model is suggested.

Projectile and targetK-shell ionization cross sections induced by 3.6-, 4.7-, and 5.9 MeV/u132Xe ions and 1.4-, 3.6-, 4.7-, and 5.9 MeV/u208Pb ions from the UNILAC in thin solid targets between C and U are measured. The cross sections are discussed in terms of the molecular model of innershell vacancy production in heavy ion-atom collisions. The sharing of 2p1/2s vacancies between theK shells of the two collision partners in these very heavy ion-atom collisions is found to deviate from the Meyerhof-Demkov formula forR?10-2. The measured ionization cross sections are compared with theoretical calculations for 1ss and 2p1/2s excitation cross sections. AZUA=Z1+Z2 dependence is found independent ofZ1/Z2. Outer-shell vacancy configurations measured in these close encounters are reported.

Projectile (Z1) and target (Z2)K-vacancy production cross sections induced by 3.6-, 4.75-, and 5.9-MeV/amu238U ions in selected targets between C and U are reported. The cross sections are discussed within the context of the molecular model of inner-shell vacancy production in heavy-ion-atom collisions. The measured 1ss and 2ps excitation cross sections are compared with semiempirical formulas, and with the perturbed-stationary-states calculations of Betz et al. The dependence of these cross sections onZu=Z1+Z2 agrees well with the Betz calculations. However, the measured cross sections are factors of 2 to 4 (1ss) and 4 to 5 (2ps) larger than the theoretical values.

K-, L- andM-x ray production cross sections for the molecular excitation regime in heavy ion-atom collisions (Z1+Z2≧100) are reported for the projectile velocity range 1.3–3.7 a.u. Outer-shell vacancy configurations of the collision partners having experienced inner shell vacancy creating collisions are deduced from the x-ray spectra. The influence of outer shell vacancy occupation on fluorescence yields is discussed and vacancy production cross sections are derived from x-ray production cross sections.

From 90° line width analysis ofKa1 lines excited in very heavy ion-atom collisions (Z1 +Z2>137) mean impact parameters for the ionization probability are derived. The experimental mean impact parameters are shown to obey the Bang-Hansteen scaling rule¯bE(R)=C · hv correlating the minimum momentum transferE(R)/v and the mean impact parameterb. Theoretical values of the constantC are (0.8±0.1) for 2p1/2s excitation and (1.0±0.1) for 1ss excitation in the rangeZ1+Z2=140–160. It is proposed to apply the scaling rule as a spectroscopic tool to study the 1ss and 2p1/2s levels in superheavy quasimolecules. The need of a sound theoretical base justifying the application of the scaling rule is emphasized.

Using particle x-ray coincidence techniques, the probability to produceK-shell vacancies in 4.7 MeV/u Pb+Z2 (42?Z2?92) collisions for impact parametersb<100 fm was measured. For these impact parameters, the 1ss excitation probability is greater than 1 s 10-2 and the 2p1/2s excitation probability is greater than 1 s 10-1. Binding energies of the 1ss state derived from the measured probabilities agree well with theoretical calculations.

TheM4, 5N4, 5N4, 5 Auger spectrum of xenon has been measured with high resolution. Theoretical line intensities and relative line energies for this spectrum have been calculated applyingjj coupling to the initial states and intermediate coupling and configuration interaction to the final states. Two facts indicate that correlation effects are only small in the present case: The application of configuration interaction gives only small changes in line intensities and the experimental line intensities are found to be in good agreement with theoretical results, calculated without configuration interaction.

Using particle x-ray coincidence techniques, the probability forK shell ionization has been measured absolutely at two impact parameters for collisions of 5.8 MeV/amu208Pb on Ag and Au. In the asymmetric collision system Pb-Ag, the 1ss excitation probability of the PbK shell is 2.2% at 25 fm impact parameter, and an exponential probability distribution falls off too quickly to account for the measured total cross section. For the symmetric system Pb-Au, the latter conclusion is also made for the 2ps excitation probability although in this case, the probability is much larger being 29% at 42 fm.

The impact parameter dependence of the 1ss excitation probability for 4.7 MeV/u Xe + Au collisions has been measured for impact parameters between 40 and 200 fm. A determination of the total 1ss excitation cross section from the data gives (10,8 ± 2)b in good agreement with results of an independent measurement.