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Intrinsically disordered protein (IDP) duplexes composed of two IDP chains cross-linked by bivalent partner proteins form scaffolds for assembly of multiprotein complexes. The N-terminal domain of dynein intermediate chain (N-IC) is one such IDP that forms a bivalent scaffold with multiple dynein light chains including LC8, a hub protein that promotes duplex formation of diverse IDP partners. N-IC also binds a subunit of the dynein regulator, dynactin. Here we characterize interactions of a yeast ortholog of N-IC (N-Pac11) with yeast LC8 (Dyn2) or with the intermediate chain-binding subunit of yeast dynactin (Nip100). Residue level changes in Pac11 structure are monitored by NMR spectroscopy, and binding energetics are monitored by isothermal titration calorimetry (ITC). N-Pac11 is monomeric and primarily disordered except for a single α-helix (SAH) at the N terminus and a short nascent helix, LH, flanked by the two Dyn2 recognition motifs. Upon binding Dyn2, the only Pac11 residues making direct protein-protein interactions are in and immediately flanking the recognition motifs. Dyn2 binding also orders LH residues of Pac11. Upon binding Nip100, only Pac11 SAH residues make direct protein-protein interactions, but LH residues at a distant sequence position and L1 residues in an adjacent linker are also ordered. The long distance, ligand-dependent ordering of residues reveals new elements of dynamic structure within IDP linker regions.
Emerging evidence indicates that protein synthesis and degradation are necessary for the remodeling of synapses. These two processes govern cellular protein turnover, are tightly regulated, and are modulated by neuronal activity in time and space. The anisotropic anatomy of the neurons presents a challenge for the study of protein turnover, but the understanding of protein turnover in neurons and its modulation in response to activity can help us to unravel the fine-tuned changes that occur at synapses in response to activity. Here we review the key experimental evidence demonstrating the role of protein synthesis and degradation in synaptic plasticity, as well as the turnover rates of specific neuronal proteins.
Background: Tumor associated macrophages (TAMs) are known to support tumor progression and their accumulation is generally associated with poor prognosis. The shift from a tumor-attacking to a tumor-supportive macrophage phenotype is based on an educational program that, at least in part, is initiated by apoptotic tumor cells.
Aims: We explored the macrophage phenotype shift during tumor progression by analyzing the macrophage NO-output system and examining potential NO targets.
Methods: Biochemical and Molecular Biology-orientated cell culture experiments, in part using 3d-tumor spheroid models as well as animal experiments were used.
Results: Apoptotic cells polarize macrophages towards a healing, tumor-supportive phenotype. Soluble mediators released from apoptotic cells, among them the lipid sphingosine-1-phosphate (S1P), cause expression of arginase 2 in macrophages, thereby lowering citrulline/NO formation but enhancing ornithine production. Mechanistically, this is achieved via the S1P2 receptor and the CRE (cAMP-response element) binding site in the arginase 2 promoter. Reduced NO-formation is also seen in ex vivo macrophages from a xenograft model allowing restricted vs. unrestricted tumor growth based on tumor-associated S1P-formation. The theoretical ability of NO to target hypoxia-inducible factor-1 (HIF-1) and jumonji histone demethylases (JHDMs) in cells of the tumor microenvironment will be discussed in light of the iNOS/arginase balance. Moreover, data on the importance of HIF-1 in macrophages for their interaction with tumor cells, polarization, and angiogenic potential will be presented.
Conclusions: We hypothesize that apoptotic death of tumor cells and associated macrophage activation facilitates the progression of malignant disease. The macrophage polarization program affects the NO-output system and the capacity of macrophages to support or restrict tumor growth.
Combination chemotherapy with gemcitabine and cisplatin in patients with metastatic urothelial cancer of the bladder frequently results in the development of acquired drug resistance. Availability of cell culture models with acquired resistance could help to identify candidate treatments for an efficient second-line therapy. Six cisplatin- and six gemcitabine-resistant cell lines were established. Cell viability assays were performed to evaluate the sensitivity to 16 different chemotherapeutic substances. The activity of the drug transporter ATP-binding cassette transporter, subfamily B, member 1 (ABCB1, a critical mediator of multidrug resistance in cancer) was evaluated using fluorescent ABCB1 substrates. For functional assessment, cells overexpressing ABCB1 were generated by transduction with a lentiviral vector encoding for ABCB1, while zosuquidar was used for selective inhibition. In this study, 8 of 12 gemcitabine- or cisplatin-resistant cell lines were cross-resistant to carboplatin, 5 to pemetrexed, 4 to methotrexate, 3 to oxaliplatin, 5-fluorouracil, and paclitaxel, and 2 to cabazitaxel, larotaxel, docetaxel, topotecan, doxorubicin, and mitomycin c, and 1 of 12 cell lines was cross-resistant to vinflunine and vinblastine. In one cell line with acquired resistance to gemcitabine (TCC-SUPrGEMCI20), cross-resistance seemed to be mediated by ABCB1 expression. Our model identified the vinca alkaloids vinblastine and vinflunine, in Europe an already approved second-line therapeutic for metastatic bladder cancer, as the most effective compounds in urothelial cancer cells with acquired resistance to gemcitabine or cisplatin. These results demonstrate that this in vitro model can reproduce clinically relevant results and may be suitable to identify novel substances for the treatment of metastatic bladder cancer.
We present an angular thin-lens formula giving the angle of refraction β for arbitrary values of the angle of incidence α. With this formula, we find analytical results for the focal length f of a thin-lens system. The number of lenses n and their focal lengths f1,f2,…,fn are abitrary, as are the mutual distances D12,…,D(n−1)n between the lenses. All these results are exact, i.e. not restricted to small or even paraxial angles. In the literature, the 2-lens and 3-lens versions (the last one without proof or derivation) are known [1]. We present the general result for n lenses and for (the positions of) its principal planes.
Linking mathematics with reality is not new. It is also not new to use outdoor activities to learn mathematics. It seems to be new, to combine such mathematical outdoor activities with mobile technology, like the geocache community which makes use of GPS technology to guide their members to special places and points of interest. The use of mobile technologies to learn at any time and any location is known as “mobile learning”. This type of learning can be seen as an extension of eLearning. Considering the definition of O’Malley one notices that this definition does not exactly match with the idea of the MathCityMap-Project (MCM), because the learning environment in the MCM-Project is predetermined. Combined with the math trail method the project enables mobile learning within math trails with latest technology.In the MCM-Project students experience mathematics at real places and within real situations in out-of-school activities,with help of GPS-enabled smartphones and special math problems. In contrast to the paper versions of math trails we are able to give direct feedback on the solutions by using “mobile devices” such as smartphones or tablets. If the user has difficulties in solving the modeling task, stepped hints can be provided. The teacher is able to use the MCM-Portal to upload tasks developed by himself or by his students and he is also able to build a personal math trail for his students.
The hepatitis C virus (HCV) was discovered in the late 1980s. Interferon (IFN)-α was proposed as an antiviral treatment for chronic hepatitis C at about the same time. Successive improvements in IFN-α-based therapy (dose finding, pegylation, addition of ribavirin) increased the rates of sustained virologic response, i.e. the rates of curing HCV infection. These rates were further improved by adding the first available direct-acting antiviral (DAA) drugs to the combination of pegylated IFN-α and ribavirin. An IFN-free era finally started in 2014, yielding rates of sustained virologic response over 90% in patients treated for 8 to 24 weeks with all-oral regimens. Major challenges however remain in implementation of these new treatment strategies, not only in low- to middle-income countries, but also in high-income countries where the price of these therapies is still prohibitive. Elimination of HCV infection through treatment in certain areas is possible but raises major public health issues.
In many neural systems anatomical motifs are present repeatedly, but despite their structural similarity they can serve very different tasks. A prime example for such a motif is the canonical microcircuit of six-layered neo-cortex, which is repeated across cortical areas, and is involved in a number of different tasks (e.g. sensory, cognitive, or motor tasks). This observation has spawned interest in finding a common underlying principle, a ‘goal function’, of information processing implemented in this structure. By definition such a goal function, if universal, cannot be cast in processing-domain specific language (e.g. ‘edge filtering’, ‘working memory’). Thus, to formulate such a principle, we have to use a domain-independent framework. Information theory offers such a framework. However, while the classical framework of information theory focuses on the relation between one input and one output (Shannon’s mutual information), we argue that neural information processing crucially depends on the combination of multiple inputs to create the output of a processor. To account for this, we use a very recent extension of Shannon Information theory, called partial information decomposition (PID). PID allows to quantify the information that several inputs provide individually (unique information), redundantly (shared information) or only jointly (synergistic information) about the output. First, we review the framework of PID. Then we apply it to reevaluate and analyze several earlier proposals of information theoretic neural goal functions (predictive coding, infomax and coherent infomax, efficient coding). We find that PID allows to compare these goal functions in a common framework, and also provides a versatile approach to design new goal functions from first principles. Building on this, we design and analyze a novel goal function, called ‘coding with synergy’, which builds on combining external input and prior knowledge in a synergistic manner. We suggest that this novel goal function may be highly useful in neural information processing.
Sleep has been shown to subtly disrupt the spatial organization of functional connectivity networks in the brain, but in a way that largely preserves the connectivity within sensory cortices. Here we evaluated the hypothesis that sleep does impact sensory cortices, but through alteration of activity dynamics. We therefore examined the impact of sleep on hemodynamics using a method for quantifying non-random, high frequency signatures of the blood-oxygen-level dependent (BOLD) signal (amplitude variance asymmetry; AVA). We found that sleep was associated with the elimination of these dynamics in a manner that is restricted to auditory, motor and visual cortices. This elimination was concurrent with increased variance of activity in these regions. Functional connectivity between regions showing AVA during wakefulness maintained a relatively consistent hierarchical structure during wakefulness and N1 and N2 sleep, despite a gradual reduction of connectivity strength as sleep progressed. Thus, sleep is related to elimination of high frequency non-random activity signatures in sensory cortices that are robust during wakefulness. The elimination of these AVA signatures conjointly with preservation of the structure of functional connectivity patterns may be linked to the need to suppress sensory inputs during sleep while still maintaining the capacity to react quickly to complex multimodal inputs.
Dilatometric studies on single crystalline barlowite – a structurally perfect spin-1/2 Kagome system
(2015)
We present results of high-resolution thermal expansion measurements on single crystalline barlowite – a structurally perfect spin-1/2 kagome system. The data reveal strongly pronounced and anisotropic second-order phase transition anomalies at the Néel transition at TN = 16K. From these data, together with literature results on the specific heat, the uniaxial-pressure dependences of TN are derived. We find a rather large positive pressure coefficient for uniaxial pressure along the hexagonal c axis of ∂TN/∂pc = (2.3 ± 0.2) K/GPa and smaller negative in-plane pressure coefficient of ∂TN/∂pin-plane = -(0.6 ± 0.03) K/GPa. These effects result in a small positive pressure coefficient under hydrostatic-pressure conditions of ∂TN/∂phydr = (1.1 ± 0.2) K/GPa. Bond-lengths considerations indicate that inter-layer Cu-O bonds, being larger than those typically found in stable Cu-O complexes, are responsible for this behavior.
Injury of the sciatic nerve results in regulations of pro- and anti-oxidative enzymes at sites of nociceptive signaling including the injured nerve, dorsal root ganglia (DRGs), dorsal horn of the spinal cord, thalamus and somatosensory cortex (Valek et al., 2015) [1]. The present DiB paper shows immunohistochemistry of redoxins including peroxiredoxins (Prdx1–6), glutaredoxins (Glrx1, 2, 3, 5), thioredoxins (Txn1, 2) and thioredoxin reductases (Txnrd1, 2) in the DRGs, spinal cord and sciatic nerve and thalamus in naïve mice and 7 days after Spared sciatic Nerve Injury (SNI) in control mice (Hif1α-flfl) and in mice with a specific deletion of hypoxia inducible factor 1 alpha (SNS-HIF1α−/−) in DRG neurons. The sciatic nerves were immunostained for the respective redoxins and counterstained with hematoxylin. The redoxin immunoreactivity was quantified with ImageJ. For the DRGs and spinal cord the data show the quantitative assessment of the intensity of redoxin immunoreactivity transformed to rainbow pseudocolors. In addition, some redoxin examples of the ipsi and contralateral dorsal and ventral horns of the lumbar spinal cord and some redoxin examples of the thalamus are presented.
We have performed the first measurement of the coherent ψ(2S) photo-production cross section in ultra-peripheral PbPb collisions at the LHC. This charmonium excited state is reconstructed via the ψ(2S)→l+l− and ψ(2S)→J/ψπ+π− decays, where the J/ψ decays into two leptons. The analysis is based on an event sample corresponding to an integrated luminosity of about 22 μb−1. The cross section for coherent ψ(2S) production in the rapidity interval −0.9<y<0.9 is dσψ(2S)coh/dy=0.83±0.19(stat+syst) mb. The ψ(2S) to J/ψ coherent cross section ratio is 0.34−0.07+0.08(stat+syst). The obtained results are compared to predictions from theoretical models.
We present measurements of the azimuthal dependence of charged jet production in central and semi-central √sNN=2.76 TeV Pb–Pb collisions with respect to the second harmonic event plane, quantified as v2ch jet. Jet finding is performed employing the anti-kT algorithm with a resolution parameter R=0.2 using charged tracks from the ALICE tracking system. The contribution of the azimuthal anisotropy of the underlying event is taken into account event-by-event. The remaining (statistical) region-to-region fluctuations are removed on an ensemble basis by unfolding the jet spectra for different event plane orientations independently. Significant non-zero v2ch jet is observed in semi-central collisions (30–50% centrality) for 20<pTch jet<90 GeV/c. The azimuthal dependence of the charged jet production is similar to the dependence observed for jets comprising both charged and neutral fragments, and compatible with measurements of the v2 of single charged particles at high pT. Good agreement between the data and predictions from JEWEL, an event generator simulating parton shower evolution in the presence of a dense QCD medium, is found in semi-central collisions.
The production of electrons from heavy-flavour hadron decays was measured as a function of transverse momentum (pT) in minimum-bias p–Pb collisions at sNN=5.02 TeV using the ALICE detector at the LHC. The measurement covers the pT interval 0.5<pT<12 GeV/c and the rapidity range −1.065<ycms<0.135 in the centre-of-mass reference frame. The contribution of electrons from background sources was subtracted using an invariant mass approach. The nuclear modification factor RpPb was calculated by comparing the pT-differential invariant cross section in p–Pb collisions to a pp reference at the same centre-of-mass energy, which was obtained by interpolating measurements at s=2.76 TeV and s=7 TeV. The RpPb is consistent with unity within uncertainties of about 25%, which become larger for pT below 1 GeV/c. The measurement shows that heavy-flavour production is consistent with binary scaling, so that a suppression in the high-pT yield in Pb–Pb collisions has to be attributed to effects induced by the hot medium produced in the final state. The data in p–Pb collisions are described by recent model calculations that include cold nuclear matter effects.
We present results of a search for two hypothetical strange dibaryon states, i.e. the H-dibaryon and the possible Λn‾ bound state. The search is performed with the ALICE detector in central (0–10%) Pb–Pb collisions at √sNN=2.76 TeV, by invariant mass analysis in the decay modes Λn‾→d‾π+ and H-dibaryon →Λpπ−. No evidence for these bound states is observed. Upper limits are determined at 99% confidence level for a wide range of lifetimes and for the full range of branching ratios. The results are compared to thermal, coalescence and hybrid UrQMD model expectations, which describe correctly the production of other loosely bound states, like the deuteron and the hypertriton.
The pseudorapidity (η) and transverse-momentum (pT) distributions of charged particles produced in proton–proton collisions are measured at the centre-of-mass energy √s=13 TeV. The pseudorapidity distribution in |η|<1.8 is reported for inelastic events and for events with at least one charged particle in |η|<1. The pseudorapidity density of charged particles produced in the pseudorapidity region |η|<0.5 is 5.31±0.18 and 6.46±0.19 for the two event classes, respectively. The transverse-momentum distribution of charged particles is measured in the range 0.15<pT<20 GeV/c and |η|<0.8 for events with at least one charged particle in |η|<1. The evolution of the transverse momentum spectra of charged particles is also investigated as a function of event multiplicity. The results are compared with calculations from PYTHIA and EPOS Monte Carlo generators.
We construct net baryon number and strangeness susceptibilities as well as correlations between electric charge, strangeness and baryon number from experimental data at midrapidity of the ALICE Collaboration at CERN. The data were taken in central Pb–Pb collisions at sNN=2.76 TeV and cover one unit of rapidity. The resulting fluctuations and correlations are consistent with Lattice QCD results at the chiral crossover pseudocritical temperature Tc≃155 MeV. This agreement lends strong support to the assumption that the fireball created in these collisions is of thermal origin and exhibits characteristic properties expected in QCD at the transition from the quark gluon plasma to the hadronic phase. The volume of the fireball for one unit of rapidity at Tc is found to exceed 3000 fm3. A detailed discussion on uncertainties in the temperature and volume of the fireball is presented. The results are linked to pion interferometry measurements and predictions from percolation theory.
Background. Bile leakage testing may help to detect and reduce the incidence of biliary leakage after hepatic resection. This review was performed to investigate the value of the White-test in identifying intraoperative biliary leakage and avoiding postoperative leakage.
Material and methods. A systematic review and meta-analysis was performed. Two researchers performed literature research. Primary outcome measure was the incidence of post-hepatectomy biliary leakage; secondary outcome measure was the ability of detecting intraoperative biliary leakage with the help of the White-test.
Results. A total of 4 publications (including original data from our center) were included in the analysis. Evidence levels of the included studies had medium quality of 2b (individual cohort studies including low quality randomized controlled trials). Use of the White-test led to a significant reduction of post-operative biliary leakage [OR: 0.3 (95% CI: 0.14, 0.63), p = 0.002] and led to a significant higher intraoperative detection of biliary leakages [OR: 0.03 (95%CI: 0.02, 0.07), p < 0.00001].
Conclusion. Existing evidence implicates the use of the White-test after hepatic resection to identify bile leaks intraoperatively and thus reduce incidence of post-operative biliary leakage. Nonetheless, there is a requirement for a high-quality randomized controlled trial with adequately powered sample-size to confirm findings from the above described studies and further increase evidence in this field.
Hepatology highlights
(2015)
Previous study showed that kaffir lime leaf contains alkaloid, flavonoid, terpenoid, tannin and saponin. The objective of this study was to examine the cytotoxic effect of kaffir lime leaf extract on cervical cancer and neuroblastoma cell lines. The method used for this research to determine cell viability was an 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Results showed that an ethyl acetate extract had an IC50 for HeLa cells, UKF-NB3, IMR-5 and SK-N-AS parental cells of 40.7 μg · mL–1, 28.4 μg · mL–1, 14.1 μg · mL–1, and 25.2 μg · mL–1 respectively. Furthermore, the IC50 of chloroform extracts for HeLa cells, UKF-NB3, IMR-5 and SK-N-AS parental were 17.6 μg · mL–1, 18.9 μg · mL–1, 6.4 μg · mL–1, and 9.4 μg · mL–1 respectively. These data showed that kaffir lime extract reduces the viability of cervical and neuroblastoma cell lines and may have potential as anti-cancer compounds.
Intrinsic covariation of brain activity has been studied across many levels of brain organization. Between visual areas, neuronal activity covaries primarily among portions with similar retinotopic selectivity. We hypothesized that spontaneous inter-areal co-activation is subserved by neuronal synchronization. We performed simultaneous high-density electrocorticographic recordings across several visual areas in awake monkeys to investigate spatial patterns of local and inter-areal synchronization. We show that stimulation-induced patterns of inter-areal co-activation were reactivated in the absence of stimulation. Reactivation occurred through both, inter-areal co-fluctuation of local activity and inter-areal phase synchronization. Furthermore, the trial-by-trial covariance of the induced responses recapitulated the pattern of inter-areal coupling observed during stimulation, i.e. the signal correlation. Reactivation-related synchronization showed distinct peaks in the theta, alpha and gamma frequency bands. During passive states, this rhythmic reactivation was augmented by specific patterns of arrhythmic correspondence. These results suggest that networks of intrinsic covariation observed at multiple levels and with several recording techniques are related to synchronization and that behavioral state may affect the structure of intrinsic dynamics.
Die Sammlung von Aufsätzen des Frankfurter Lehrers, Erziehungswissenschaftlers und Soziologen besteht aus drei Teilen: In dem ersten Teil wird der Frage nachgegangen, aus welcher Perspektive heraus Unterricht hermeneutisch erschlossen werden und in welche Theorietradition sich eine hermeneutische Unterrichtsforschung stellen kann bzw. sollte. In dem zweiten Teil sind sodann Aufsätze versammelt, in denen grundlegende Fragen des Unterrichts neu aufgegriffen werden: Welche Probleme stellen sich zu Beginn einer jeden Unterrichtsstunde und welche Möglichkeiten gibt es, diese zu lösen? Worauf beruht die Autorität einer Lehrperson und wie wird diese im Unterricht durch die beteiligten Akteure kommunikativ erzeugt oder auch vermindert? Wie sind Unterrichtsstörungen zu deuten und wie ist mit ihnen umzugehen, wenn davon ausgegangen wird, dass diese Momente eines Interaktionsprozesses sind, die jeweils situativ emergieren? Was bedeutet es für Schüler, sich am Unterricht zu beteiligen? Und welche Situationen können sich ergeben, wenn die Schülerschaft einer Klasse in kultureller Hinsicht äußerst heterogen ist? Die Art und Weise, wie diese Fragen behandelt werden, ist nicht nur durch das besondere methodische Vergehen gekennzeichnet, sondern auch durch einen kasuistischen Zugang: Auf der Basis theoretischer Vorüberlegungen wird stets ein empirisches Beispiel herangezogen, um an diesem diese theoretischen Überlegungen nicht nur zu überprüfen, sondern schließlich auch weiterzuentwickeln. Dabei ist die Stoßrichtung stets dieselbe: Die Vielzahl möglicher Deutungen von Unterricht wird nicht bestritten, doch die Fruchtbarkeit einer dezidiert pädagogischen Deutung dieses Geschehens wird immer wieder hervorgehoben. Abgeschlossen wird der Band mit Aufsätzen zu Fragen der Professionalisierung von Lehrerinnen und Lehrern. So wird das Verhältnis zwischen der Didaktik, vor allem didaktischer Theorien und der Theorie der Professionalisierung ausgelotet. Und es wird der Frage nachgegangen, welche Konsequenzen sich aus der pädagogischen Kasuistik für die Professionalisierung von Lehrpersonen sowie für die Theorie der Professionalisierung ziehen lassen. Auch diese Fragen werden jeweils mit Bezug auf empirische Beispiele erörtert. (DIPF/Verlag)
Plant communities provide floral resource-landscapes for pollinators. Yet, it is insufficiently understood how these landscapes shape pollinator-mediated interactions among multiple plant species. Here, we study how pollinators and the seed set of plants respond to the distribution of a floral resource (nectar sugar) in space and across plant species, inflorescences and flowering phenologies. In a global biodiversity hotspot, we quantified floral resource-landscapes on 27 sites of 4 ha comprising 127,993 shrubs of 19 species. Visitation rates of key bird pollinators strongly depended on the phenology of site-scale resource amounts. Seed set of focal plants increased with resources of conspecific neighbours and with site-scale resources, notably with heterospecific resources of lower quality (less sugar per inflorescence). Floral resources are thus a common currency determining how multiple plant species interact via pollinators. These interactions may alter conditions for species coexistence in plant communities and cause community-level Allee effects that promote extinction cascades.
Two types of particles exist in the atmosphere, primary and secondary particles. While primary particles such as soot, mineral dust, sea salt particles or pollen are introduced directly as particles into the atmosphere, secondary particles are formed in the atmosphere by condensation of gases. The formation of such new aerosol particles takes place frequently and at a broad variety of atmospheric conditions and geographic locations. A considerable fraction of the atmospheric particles is formed by such nucleation processes. The newly formed particles may grow by condensation to sizes where they are large enough to act as cloud condensation nuclei and therefore may affect cloud properties. The fundamental processes of aerosol nucleation are described and typical atmospheric observations are discussed. Two recent studies are introduced that potentially change our current understanding of atmospheric nucleation substantially.
The method of relative self absorption is based on the technique of nuclear resonance fluorescence measurements. It allows for a model-independent determination of ground-state transition widths, natural level widths, and, consequently, of branching ratios to the ground state for individual excitations. Relative self–absorption experiments have been performed on the nuclei 6Li and 140Ce. In order to investigate the total level width for the 0+1, T = 1 level at 3563 keV in 6Li, a high-precision self-absorption measurement has been performed. In the case of 140Ce, self absorption has been applied for the first time to study decay widths of dipole-excited states in the energy regime of the pygmy dipole resonance.
A series of photon scattering experiments has been performed on the double-beta decay partners 76Ge and 76Se, in order to investigate their dipole response up to the neutron separation threshold. Gamma-ray beams from bremsstrahlung at the S-DALINAC and from Compton-backscattering at HIGS have been used to measure absolute cross sections and parities of dipole excited states, respectively. The HIGS data allows for indirect measurement of averaged branching ratios, which leads to significant corrections in the observed excitation cross sections. Results are compared to statistical calculations, to test photon strength functions and the Axel-Brink hypothesis.
The dynamics of strange pseudoscalar and vector mesons in hot and dense nuclear matter is studied within a chiral unitary framework in coupled channels. Our results set up the starting point for implementations in microscopic transport approaches of heavy-ion collisions, particularly at the conditions of the forthcoming experiments at GSI/FAIR and NICA-Dubna. In the K̄ N sector we focus on the calculation of (off-shell) transition rates for the most relevant binary reactions involved in strangeness production close to threshold energies, with special attention to the excitation of sub-threshold hyperon resonances and isospin effects (e.g. K̄ p vs K̄ n). We also give an overview of recent theoretical developments regarding the dynamics of strange vector mesons (K*, K̄* and ϕ) in the nuclear medium, in connection with experimental activity from heavy-ion collisions and nuclear production reactions. We emphasize the role of hadronic decay modes and the excitation of hyperon resonances as the driving mechanisms modifying the properties of vector mesons.
We analysed our experimental recent findings of the dipole response of the odd-mass stable nucleus 205Tl within the quasi-particle phonon model. Using the phonon basis constructed for the neighbouring 204Hg and wave function configurations for 205Tl consisting of a mixture of quasiparticle ⊗ N-phonon configurations (N=0,1,2), only one group of fragmented dipole excited states has been reproduced at 5.5 MeV in comparison to the experimental distribution which shows a second group at about 5 MeV. The computed dipole transition strengths are mainly of E1 character which could be associated to the pygmy dipole resonance.
In addition to the well-established quadrupole mixed-symmetry states, octupole and hexadecapole excitations with mixed-symmetry character have been recently proposed for the N = 52 isotones 92Zr and 94Mo. We performed two inelastic proton-scattering experiments to study this kind of excitations in the heaviest stable N = 52 isotone 96Ru. From the combined experimental data of both experiments absolute transition strengths were extracted.
The decay behavior of low-lying dipole states in 140Ce was investigated exploiting the γ3-setup at the HIγS facility using quasi-monochromatic photon beams. Branching ratios of individual excited states as well as average branching ratios to low-lying states have been extracted using γ – γ coincidence measurements. The comparison of the average branching ratios to QPM calculations shows a remarkable agreement between experiment and theory in the energy range from 5.0 to 8.5 MeV.
The complementary (γ, γ′) and (α, α′γ) reactions were used to study the isospin properties of low-lying E1 excitations in the doubly-magic nucleus 48Ca. In contrast to heavier nuclei, a state-to-state change in isospin character was revealed in 48Ca and a dominant isoscalar excitation was found which is interpreted as an isoscalar oscillation. Recently, protons at 80 MeV were used as an additional hadronic probe in a p-γ coincidence experiment on 140Ce for the first time. Results of the experiments on 48Ca and first results of the 140Ce will be presented in this contribution.
The p nucleus 92Mo is believed to be mainly produced through photodisintegration reactions in type II supernovae. However, this production scenario cannot solely account for the observed solar relative isotopic abundance of 92Mo. Additional production scenarios have been suggested to explain this discrepancy. One of these scenarios could be the production of 92Mo in type Ia supernovae via a chain of proton-capture reactions. To verify this scenario, an accurate knowledge of the involved reaction rates is important. We measured the cross section of 90Zr(p,γ) reaction using an enriched 90Zr target by means of in-beam γ-ray spectroscopy in the energy range between 3.6MeV and 5.1MeV. Since the reactions 90Zr(p,γ) and 91Zr(p,n) produce the same nucleus, the contributions of both reactions have to be disentangled. This procedure is explained in this contribution in detail.
We present a nucleosynthesis sensitivity study for the γ-process in a Supernova type II model within the NuGrid research platform. The simulations aimed at identifying the relevant local production and destruction rates for the p-nuclei of molybdenum and at determining the sensitivity of the final abundances to these rates. We show that local destruction rates strongly determine the abundance of 92Mo and 94Mo, and quantify the impact.
The ALICE detector at the LHC is used to study the properties of the Quark-Gluon Plasma produced in heavy-ion collisions. As a reference measurement, also the analysis of proton-proton (pp) collisions is very important. In the study presented here, event-by-event fluctuations of the mean transverse momentum are analysed in pp collisions at √s = 0.9, 2.76 and 7 TeV, and Pb–Pb collisions at √sNN = 2.76 TeV as a function of the charged-particle multiplicity. In both systems, dynamical fluctuations beyond the statistical expectation are observed. In pp collisions, no significant dependence on collision energy is found, even in comparison to inclusive results at much lower collision energies. Likewise, central A–A collisions show only little dependence on collision energy. The multiplicity dependence observed in peripheral Pb–Pb data is in agreement with that in pp collisions. Going to more central Pb–Pb collisions, a clear deviation from this trend is found, reaching a significant reduction of the fluctuations in most central collisions. Comparisons toMonte Carlo event generators show good agreement in pp, but rather large differences in Pb–Pb collisions.
The advent of improved experimental and theoretical techniques has brought a lot of attention to the electric dipole (E1) response of atomic nuclei in the last decade. The extensive studies have led to the observation and interpretation of a concentration of E1 strength energetically below the Giant Dipole Resonance in many nuclei. This phenomenon is commonly denoted as Pygmy Dipole Resonance (PDR). This contribution will summarize the most important results obtained using different experimental probes, define the challenges to gain a deeper understanding of the excitations, and discuss the newest experimental developments.
his contribution aims to give a basic overview of the latest results regarding the production of resonances in different collision systems. The results were extracted from experimental data collected with HADES that is a multipurpose detector located at the GSI Helmholtzzentrum, Darmstadt. The main points discussed here are: the properties of the strange resonances Λ(1405) and Σ(1385), the role of Δ’s as a source of pions in the final state, the production dynamics reflected in form of differential cross sections, and the role of the ϕ meson as a source for K− particles.
n this paper we report on the investigation of baryonic resonance production in proton-proton collisions at the kinetic energies of 1.25 GeV and 3.5 GeV, based on data measured with HADES. Exclusive channels npπ+ and ppπ0 as well as ppe+e− were studied simultaneously in the framework of a one-boson exchange model. The resonance cross sections were determined from the one-pion channels for Δ(1232) and N(1440) (1.25 GeV) as well as further Δ and N* resonances up to 2 GeV/c2 for the 3.5 GeV data. The data at 1.25 GeV energy were also analysed within the framework of the partial wave analysis together with the set of several other measurements at lower energies. The obtained solutions provided the evolution of resonance production with the beam energy, showing a sizeable non-resonant contribution but with still dominating contribution of Δ(1232)P33. In the case of 3.5 GeV data, the study of the ppe+e− channel gave the insight on the Dalitz decays of the baryon resonances and, in particular, on the electromagnetic transition form-factors in the time-like region. We show that the assumption of a constant electromagnetic transition form-factors leads to underestimation of the yield in the dielectron invariant mass spectrum below the vector mesons pole. On the other hand, a comparison with various transport models shows the important role of intermediate ρ production, though with a large model dependency. The exclusive channels analysis done by the HADES collaboration provides new stringent restrictions on the parameterizations used in the models.
Evidence for hydrodynamical flow in AA or in pA collisons is to a large extent obtained from the observation of identified hadrons, such as pions, kaons, and protons. But much more information in particular about the late stage can be obtained by also considering unstable particles, which decay during the lifetime of the expanding hadronic matter. We therefore started to use EPOS3, a unified approach for pp, pA, and AA scattering, to investigate the production of stable and unstable particles.
We discuss the behavior of dynamically-generated charmed baryonic resonances in matter within a unitarized coupled-channel model consistent with heavy-quark spin symmetry. We analyze the implications for the formation of D-meson bound states in nuclei and the propagation of D mesons in heavy-ion collisions from RHIC to FAIR energies.
The neutron capture cross section of 58Ni was measured at the neutron time of flight facility n_TOF at CERN, from 27 meV to 400 keV neutron energy. Special care has been taken to identify all the possible sources of background, with the so-called neutron background obtained for the first time using high-precision GEANT4 simulations. The energy range up to 122 keV was treated as the resolved resonance region, where 51 resonances were identified and analyzed by a multilevel R-matrix code SAMMY. Above 122 keV the code SESH was used in analyzing the unresolved resonance region of the capture yield. Maxwellian averaged cross sections were calculated in the temperature range of kT = 5 – 100 keV, and their astrophysical implications were investigated.
After reviewing the description of an unstable state in the framework of nonrelativistic Quantum Mechanics (QM) and relativistic Quantum Field Theory (QFT), we consider the effect of pulsed, ideal measurements repeated at equal time intervals on the lifetime of an unstable system. In particular, we investigate the case in which the ‘bare’ survival probability is an exact exponential (a very good approximation in both QM and QFT), but the measurement apparatus can detect the decay products only in a certain energy range. We show that the Quantum Zeno Effect can occur in this framework as well.
In the framework of the so-called extended linear sigma model (eLSM), we include a pseudoscalar glueball with a mass of 2.6 GeV (as predicted by Lattice-QCD simulations) and we compute the two- and three-body decays into scalar and pseudoscalar mesons. This study is relevant for the future PANDA experiment at the FAIR facility. As a second step, we extend the eLSM by including the charm quark according to the global U(4)R × U(4)L chiral symmetry. We compute the masses, weak decay constants and strong decay widths of open charmed mesons. The precise description of the decays of open charmed states is important for the CBM experiment at FAIR.
Dilepton production in heavy-ion collisions at top SPS energy is investigated within a coarse-graining approach that combines an underlying microscopic evolution of the nuclear reaction with the application of medium-modified spectral functions. Extracting local energy and baryon density for a grid of small space-time cells and going to each cell’s rest frame enables to determine local temperature and chemical potential by application of an equation of state. This allows for the calculation of thermal dilepton emission. We apply and compare two different spectral functions for the ρ: A hadronic many-body calculation and an approach that uses empirical scattering amplitudes. Quantitatively good agreement of the model calculations with the data from the NA60 collaboration is achieved for both spectral functions, but in detail the hadronic many-body approach leads to a better description, especially of the broadening around the pole mass of the ρ and for the low-mass excess. We further show that the presence of a pion chemical potential significantly influences the dilepton yield.
Due to their penetrating nature, electromagnetic probes, i.e., lepton-antilepton pairs (dileptons) and photons are unique tools to gain insight into the nature of the hot and dense medium of strongly-interacting particles created in relativistic heavy-ion collisions, including hints to the nature of the restoration of chiral symmetry of QCD. Of particular interest are the spectral properties of the electromagnetic current-correlation function of these particles within the dense and/or hot medium. The related theoretical investigations of the in-medium properties of the involved particles in both the partonic and hadronic part of the QCD phase diagram underline the importance of a proper understanding of the properties of various hadron resonances in the medium.
Future FAIR experiments have to deal with very high input rates, large track multiplicities, make full event reconstruction and selection on-line on a large dedicated computer farm equipped with heterogeneous many-core CPU/GPU compute nodes. To develop efficient and fast algorithms, which are optimized for parallel computations, is a challenge for the groups of experts dealing with the HPC computing. Here we present and discuss the status and perspectives of the data reconstruction and physics analysis software of one of the future FAIR experiments, namely, the CBM experiment.
We compute potentials of two static antiquarks in the presence of two quarks qq of finite mass using lattice QCD. In a second step we solve the Schrödinger equation, to determine, whether the resulting potentials are sufficiently attractive to host a bound state, which would indicate the existence of a stable qqb¯b¯ tetraquark. We find a bound state for qq=(ud−du)/2–√ with corresponding quantum numbers I(JP)=0(1+) and evidence against the existence of bound states with isospin I=1 or qq∈{cc,ss}.
The neutron capture cross section of the s-process branch nucleus 63Ni affects the abundances of other nuclei in its region, especially 63Cu and 64Zn. In order to determine the energy-dependent neutron capture cross section in the astrophysical energy region, an experiment at the Los Alamos National Laboratory has been performed using the calorimetric 4πBaF2 array DANCE. The (n,γ) cross section of 63Ni has been determined relative to the well-known 197Au standard with uncertainties below 15%. Various 63Ni resonances have been identified based on the Q value. Furthermore, the s-process sensitivity of the new values was analyzed with the new network calculation tool NETZ.
Neutron capture cross sections of unstable isotopes are important for neutron-induced nucleosynthesis as well as for technological applications. A combination of a radioactive beam facility, an ion storage ring and a high flux reactor would allow a direct measurement of neutron induced reactions over a wide energy range on isotopes with half lives down to minutes. The idea is to measure neutron-induced reactions on radioactive ions in inverse kinematics. This means, the radioactive ions will pass through a neutron target. In order to efficiently use the rare nuclides as well as to enhance the luminosity, the exotic nuclides can be stored in an ion storage ring. The neutron target can be the core of a research reactor, where one of the central fuel elements is replaced by the evacuated beam pipe of the storage ring. Using particle detectors and Schottky spectroscopy, most of the important neutron-induced reactions, such as (n,γ), (n,p), (n,α), (n,2n), or (n,f), could be investigated.
The measurement of the mass differences for systems bound by the strong force has reached a very high precision with protons and anti-protons1,2. The extension of such measurement from (anti-)baryons to (anti-)nuclei allows one to probe any difference in the interactions between nucleons and anti-nucleons encoded in the (anti-)nuclei masses. This force is a remnant of the underlying strong interaction among quarks and gluons and can be described by effective theories3, but cannot yet be directly derived from quantum chromodynamics. Here we report a measurement of the difference between the ratios of the mass and charge of deuterons (d) and anti-deuterons (), and 3He and nuclei carried out with the ALICE (A Large Ion Collider Experiment)4 detector in Pb–Pb collisions at a centre-of-mass energy per nucleon pair of 2.76 TeV. Our direct measurement of the mass-over-charge differences confirms CPT invariance to an unprecedented precision in the sector of light nuclei5,6. This fundamental symmetry of nature, which exchanges particles with anti-particles, implies that all physics laws are the same under the simultaneous reversal of charge(s) (charge conjugation C), reflection of spatial coordinates (parity transformation P) and time inversion (T).
Exclusive measurements of quasi-free proton scattering reactions in inverse and complete kinematics
(2015)
Quasi-free scattering reactions of the type (p, 2p)were measured for the first time exclusively in com-plete and inverse kinematics, using a 12C beam at an energy of ∼400MeV/u as a benchmark. This new technique has been developed to study the single-particle structure of exotic nuclei in experiments with radioactive-ion beams. The outgoing pair of protons and the fragments were measured simultaneously, enabling an unambiguous identification of the reaction channels and a redundant measurement of the kinematic observables. Both valence and deeply-bound nucleon orbits are probed, including those leading to unbound states of the daughter nucleus. Exclusive (p, 2p)cross sections of 15.8(18)mb, 1.9(2)mb and 1.5(2)mb to the low-lying 0p-hole states overlapping with the ground state (3/2−) and with the bound excited states of 11B at 2.125MeV (1/2−) and 5.02MeV (3/2−), respectively, were determined via γ-ray spectroscopy. Particle-unstable deep-hole states, corresponding to proton removal from the 0s-orbital, were studied via the invariant-mass technique. Cross sections and momentum distributions were ex-tracted and compared to theoretical calculations employing the eikonal formalism. The obtained results are in a good agreement with this theory and with direct-kinematics experiments. The dependence of the proton–proton scattering kinematics on the internal momentum of the struck proton and on its sep-aration energy was investigated for the first time in inverse kinematics employing a large-acceptance measurement.
Partial wave analysis of the reaction p(3.5 GeV) + p → pK +Λ to search for the "ppK−" bound state
(2015)
Employing the Bonn–Gatchina partial wave analysis framework (PWA), we have analyzed HADES data of the reaction p(3.5 GeV) + p → pK +Λ. This reaction might contain information about the kaonic cluster “ppK −” (with quantum numbers J P = 0− and total isospin I = 1/2) via its decay into pΛ. Due to interference effects in our coherent description of the data, a hypothetical KNN (or, specifically “ppK −”) cluster signal need not necessarily show up as a pronounced feature (e.g. a peak) in an invariant mass spectrum like pΛ. Our PWA analysis includes a variety of resonant and non-resonant intermediate states and delivers a good description of our data (various angular distributions and two-hadron invariant mass spectra) without a contribution of a KNN cluster. At a confidence level of CLs = 95% such a cluster cannot contribute more than 2–12% to the total cross section with a pK +Λ final state, which translates into a production cross-section between 0.7 μb and 4.2 μb, respectively. The range of the upper limit depends on the assumed cluster mass, width and production process.
A data-driven method was applied to Au+Au collisions at √sNN = 200 GeV made with the STAR detector at RHIC to isolate pseudorapidity distance η-dependent and η-independent correlations by using two- and four-particle azimuthal cumulant measurements. We identified a η-independent component of the correlation, which is dominated by anisotropic flow and flow fluctuations. It was also found to be independent of η within the measured range of pseudorapidity |η| < 1. In 20–30% central Au+Au collisions, the relative flow fluctuation was found to be 34%±2%(stat.)±3%(sys.) for particles with transverse momentum pT less than 2 GeV/c. The η-dependent part, attributed to nonflow correlations, is found to be 5% ± 2%(sys.) relative to the flow of the measured second harmonic cumulant at |η| > 0.7.
The transverse momentum (pT) spectrum and nuclear modification factor (RAA) of reconstructed jets in 0–10% and 10–30% central Pb–Pb collisions at √sNN = 2.76 TeV were measured. Jets were reconstructed using the anti-kT jet algorithm with a resolution parameter of R = 0.2 from charged and neutral particles, utilizing the ALICE tracking detectors and Electromagnetic Calorimeter (EMCal). The jet pT spectra are reported in the pseudorapidity interval of |ηjet| < 0.5 for 40 < pT, jet < 120 GeV/c in 0–10% and for 30 < pT, jet < 100 GeV/c in 10–30% collisions. Reconstructed jets were required to contain a leading charged particle with pT > 5 GeV/c to suppress jets constructed from the combinatorial background in Pb–Pb collisions. The leading charged particle requirement applied to jet spectra both in pp and Pb–Pb collisions had a negligible effect on the RAA. The nuclear modification factor RAA was found to be 0.28 ± 0.04 in 0–10% and 0.35 ± 0.04 in 10–30% collisions, independent of pT, jet within the uncertainties of the measurement. The observed suppression is in fair agreement with expectations from two model calculations with different approaches to jet quenching.
Measurement of electrons from heavy-flavour hadron decays in p–Pb collisions at √sNN = 5.02 TeV
(2015)
The production of electrons from heavy-flavour hadron decays was measured as a function of transverse momentum (pT) in minimum-bias p–Pb collisions at √sNN = 5.02 TeV using the ALICE detector at the LHC. The measurement covers the pT interval 0.5 < pT < 12 GeV/c and the rapidity range −1.065 < ycms < 0.135 in the centre-of-mass reference frame. The contribution of electrons from background sources was subtracted using an invariant mass approach. The nuclear modification factor RpPb was calculated by comparing the pT-differential invariant cross section in p–Pb collisions to a pp reference at the same centre-of-mass energy, which was obtained by interpolating measurements at √s = 2.76 TeV and √s = 7 TeV. The RpPb is consistent with unity within uncertainties of about 25%, which become larger for pT below 1 GeV/c. The measurement shows that heavy-flavour production is consistent with binary scaling, so that a suppression in the high-pT yield in Pb–Pb collisions has to be attributed to effects induced by the hot medium produced in the final state. The data in p–Pb collisions are described by recent model calculations that include cold nuclear matter effects.
Effect of event selection on jetlike correlation measurement in d+Au collisions at √sNN = 200 GeV
(2015)
Dihadron correlations are analyzed in √sNN = 200 GeV d + Au collisions classified by forward charged particle multiplicity and zero-degree neutral energy in the Au-beam direction. It is found that the jetlike correlated yield increases with the event multiplicity. After taking into account this dependence, the non-jet contribution on the away side is minimal, leaving little room for a back-to-back ridge in these collisions.
We report on the production of inclusive Υ (1S) and Υ (2S) in p–Pb collisions at √sNN = 5.02 TeV at the LHC. The measurement is performed with the ALICE detector at backward (−4.46 < ycms < −2.96) and forward (2.03 .< ycms < 3.53) rapidity down to zero transverse momentum. The production cross sections of the Υ (1S) and Υ (2S) are presented, as well as the nuclear modification factor and the ratio of the forward to backward yields of Υ (1S). A suppression of the inclusive Υ (1S) yield in p–Pb collisions with respect to the yield from pp collisions scaled by the number of binary nucleon–nucleon collisions is observed at forward rapidity but not at backward rapidity. The results are compared to theoretical model calculations including nuclear shadowing or partonic energy loss effect.
Two-particle angular correlations between unidentified charged trigger and associated particles are measured by the ALICE detector in p–Pb collisions at a nucleon–nucleon centre-of-mass energy of 5.02 TeV. The transverse-momentum range 0.7 < pT,assoc < pT,trig < 5.0 GeV/c is examined, to include correlations induced by jets originating from low momentum-transfer scatterings (minijets). The correlations expressed as associated yield per trigger particle are obtained in the pseudorapidity range |η| < 0.9. The near-side long-range pseudorapidity correlations observed in high-multiplicity p–Pb collisions are subtracted from both near-side short-range and away-side correlations in order to remove the non-jet-like components. The yields in the jet-like peaks are found to be invariant with event multiplicity with the exception of events with low multiplicity. This invariance is consistent with the particles being produced via the incoherent fragmentation of multiple parton–parton scatterings, while the yield related to the previously observed ridge structures is not jet-related. The number of uncorrelated sources of particle production is found to increase linearly with multiplicity, suggesting no saturation of the number of multi-parton interactions even in the highest multiplicity p–Pb collisions. Further, the number scales only in the intermediate multiplicity region with the number of binary nucleon–nucleon collisions estimated with a Glauber Monte-Carlo simulation.
A measurement of dijet correlations in p–Pb collisions at √sNN = 5.02 TeV with the ALICE detector is presented. Jets are reconstructed from charged particles measured in the central tracking detectors and neutral energy deposited in the electromagnetic calorimeter. The transverse momentum of the full jet (clustered from charged and neutral constituents) and charged jet (clustered from charged particles only) is corrected event-by-event for the contribution of the underlying event, while corrections for underlying event fluctuations and finite detector resolution are applied on an inclusive basis. A projection of the dijet transverse momentum, kTy = pch+ne T,jet sin(ϕdijet) with ϕdijet the azimuthal angle between a full and charged jet and pch+ne T,jet the transverse momentum of the full jet, is used to study nuclear matter effects in p–Pb collisions. This observable is sensitive to the acoplanarity of dijet production and its potential modification in p–Pb collisions with respect to pp collisions. Measurements of the dijet kTy as a function of the transverse momentum of the full and recoil charged jet, and the event multiplicity are presented. No significant modification of kTy due to nuclear matter effects in p–Pb collisions with respect to the event multiplicity or a PYTHIA8 reference is observed.
We have performed the first measurement of the coherent ψ(2S) photo production cross section in ultraperipheral Pb–Pb collisions at the LHC. This charmonium excited state is reconstructed via the ψ(2S) → l +l − and ψ(2S) → J/ψπ+π− decays, where the J/ψ decays into two leptons. The analysis is based on an event sample corresponding to an integrated luminosity of about 22 μb−1. The cross section for coherent ψ(2S) production in the rapidity interval −0.9 < y < 0.9 is dσcoh ψ(2S)/dy = 0.83±0.19 stat+syst mb. The ψ(2S) to J/ψ coherent cross section ratio is 0.34+0.08 −0.07(stat + syst). The obtained results are compared to predictions from theoretical models.
Dihadron angular correlations in d + Au collisions at √sNN = 200 GeV are reported as a function of the measured zero-degree calorimeter neutral energy and the forward charged hadron multiplicity in the Au-beam direction. A finite correlated yield is observed at large relative pseudorapidity (η) on the near side (i.e. relative azimuth φ ∼ 0). This correlated yield as a function of η appears to scale with the dominant, primarily jet-related, away-side (φ ∼ π) yield. The Fourier coefficients of the φ correlation, Vn = (cosnφ), have a strong η dependence. In addition, it is found that V1 is approximately inversely proportional to the mid-rapidity event multiplicity, while V2 is independent of it with similar magnitude in the forward (d-going) and backward (Au-going) directions.
Die Bestandsaufnahme der Fachkräftesituation 2014 zeigt, dass sich aus Sicht der hessischen Betriebe die Anzeichen für künftige Probleme eher verdichten. Deutlich mehr Betriebe erwarten, bei einzelnen der neu zu besetzenden Fachkraft-stellen Probleme zu bekommen, und nur noch wenige Betriebe erwarten gar keine Probleme. Hierbei ließe sich einwenden, dass negative Erwartungen noch keine realen Schwierigkeiten bedeuten müssen, zumal der Anteil der Betriebe, die aktuell bereits Stellen nicht besetzen können, weiterhin eher gering ausfällt, und die Beurteilung vor dem Hintergrund einer sehr hohen Arbeitskräftenachfrage stattfindet, die sich in dieser Form nicht fortsetzen muss. Demgegenüber stehen aber andere Daten, die einen skeptischen Blick in die Zukunft eher stützen. Insbesondere der deutliche Anstieg der Zahl der Fachkraftstellen, die im letzten halben Jahr nicht besetzt wurden, ist hier zu nennen; darüber hinaus sind hiervon, anders als in der Vergangenheit, nicht nur die kleinsten Betriebe, sondern auch kleine und mittelgroße Betriebe häufiger betroffen. Es lässt sich demnach festhalten, dass bereits heute bei der Besetzung von Fachkraftstellen nicht nur punktuell Schwierigkeiten bestehen, die sich aus Sicht der hessischen Betriebe tendenziell verstärken werden. Diese Erwartung führt mehrheitlich zu der Reaktion, stärker in das eigene betriebliche Humankapital zu investieren, insbesondere durch Qualifizierungsmaßnahmen, aber auch durch betriebliche Ausbildung. Besonders an Bedeutung gewonnen haben aber Strategien, die die Erhaltung der innerbetrieblichen Potenziale zum Ziel haben, wie eine längerfristig angelegte spezifische Personalentwicklung oder die längere Bindung älterer Fachkräfte an den Betrieb. Die Hinwendung zu den eigenen, bereits vorhandenen Potenzialen zeigt, dass die Betriebe um die Schwierigkeiten bei der externen Besetzung wissen. Absehbar ist jedoch darüber hinaus, dass für eine effektive Hebung bislang ungenutzter Potenziale die Betriebe Impulse und Unterstützungen durch Dritte brauchen. Dies betrifft z.B. die Ausweitung der Beschäftigung von Frauen, aber auch die rasche und qualifikationsadäquate berufliche Integration von Zuwanderern, bei denen die Betriebe allein und ohne flankierende Maßnahmenrasch überfordert sind. Eines der Instrumente, mittels derer eine bessere Arbeitsmarktintegration von Nichtdeutschen und somit einer Erschließung von ungenutzten Potenzialen erreicht werden kann, ist das sog. Anerkennungsgesetz. Eine erste Bilanz der betrieblichen Einschätzung des Gesetzes fällt jedoch schwer. Das Gesetz ist einer Mehrheit der Betriebe bislang unbekannt, und auch die Betriebe, die damit vertraut sind, sehen nur selten eine Relevanz für die eigene Personalgewinnung. Es gibt jedoch Anzeichen, dass insbesondere Betriebe, die aktuell oder zukünftig mit Stellenbesetzungsproblemen kämpfen, das Gesetz für ihre Personalrekrutierung nutzen möchten, auch in Branchen, in denen das bislang kaum geschah. Somit erscheint es förderlich für die Fachkräftesicherung, die Möglichkeiten des Anerkennungsgesetzes spezifisch für diese Betriebe bekannter zu machen, so dass ein höherer Anteil der Betriebe dieses Instrumentarium nutzen kann.
Beschäftigungsprognose 2016/2017 für die Region Rhein-Main :
IWAK-Betriebsbefragung im Herbst 2015
(2015)
Folgende Beschäftigungstrends in der Region Rhein-Main sind für die Jahre 2016 und 2017 zu erwarten: Die Gesamtbeschäftigung in der Region Rhein-Main wird bis Ende 2016 voraussichtlich um 1,3 Prozent steigen, was einem Zuwachs von hochgerechnet 27.400 Beschäftigten entspricht. Die Zahl der sozialversicherungspflichtig Beschäftigten steigt nach Einschätzung der Betriebe etwas weniger an, nachdem in den vergangenen Jahren hier meist höhere Zuwächse zu beobachten waren. Die künftige Beschäftigungsentwicklung verläuft in den Wirtschaftszweigen unterschiedlich. Mit einem leichten Stellenabbau rechnen in 2016 nur die Öffentliche Verwaltung und die Betriebe des Logistiksektors. Insbesondere im IuK-Sektor und im Handel werden deutliche Beschäftigungsanstiege prognostiziert. Dies gilt auch für das Gastgewerbe, das den dritthöchsten Zuwachs aller Branchen erwartet. Die Unterschiede zwischen der erwarteten Entwicklung der Gesamtbeschäftigung und der sozialversicherungspflichtigen Beschäftigung sind in den Wirtschaftszweigen eher gering. Ein Jobmotor der Region sind erneut die kleineren Betriebe, die bis Ende 2016 mit einem Beschäftigungszuwachs von zwei Prozent rechnen. Mittel- und Großbetriebe erwarten eher unterdurchschnittliche Zuwächse, wobei letztere in der Vergangenheit zumeist rückläufige Beschäftigtenzahlen meldeten. Auch mittelfristig erwarten die Betriebe in der Region Rhein-Main eher einen Anstieg der Beschäftigung; für 2017 wird mit einem weiteren Zuwachs um rund ein Prozent gerechnet. Hierbei ist aber, wie bereits bei den letztjährigen Prognosen, zu berücksichtigen, dass Prognosen über einen längeren Zeitraum auch mit höheren Unsicherheiten verbunden sind. Auch in diesem Zeithorizont rechnen die Kleinstbetriebe sowie die Gastronomiebetriebe mit deutlich mehr Beschäftigten, während in der Öffentlichen Verwaltung bzw. im Finanz-und Versicherungsbereich sowie in Großbetrieben 2017 ein leichter Rückgang der Beschäftigtenzahlen erwartet werden kann.
Zwei große Theaterzettelsammlungen mit über 100.000 Stück sind seit dem ersten Drittel des 20. Jahrhunderts in der damaligen Stadt- und heutigen Universitätsbibliothek Frankfurt am Main beheimatet und machen sie in dieser Hinsicht zu einer bedeutenden theaterhistorischen Institution im deutschsprachigen Raum: die Sammlung der Städtischen Bühnen Frankfurt am Main und ihrer Vorläufer sowie die Sammlung des Manskopfschen Musik- und Theaterhistorischen Museums...
Folgende zentrale Befunde lassen sich für Ergebnisse der Befragung 2014 festhalten: Im Herbst 2014 konnten knapp 20 Prozent aller Betriebe in der Region Rhein-Main offene Stellen nicht besetzen. Dies ist im Vergleich zu den zurückliegenden Jahren ein hoher Wert. Hochgerechnet entspricht dies etwa 38.000 offenen Stellen, was ebenfalls einen hohen Wert darstellt, der aber in der Vergangenheit schon übertroffen wurde. Größere Probleme bei der Stellenbesetzung gibt es sowohl in den personenbezogenen als auch den technischen Dienstleistungen wie auch im Baugewerbe. Besonders viele offene Stellen finden sich in den Kleinstbetrieben, nur wenige in Großbetrieben. Dieses Muster hat sich in den letzten Jahren nochmals deutlich verstärkt. Bei Ausbildungsstellen haben Betriebe die relativ höchsten Schwierigkeiten bei der Rekrutierung, bei Stellen mit niedrigem Anforderungsprofil hingegen kaum. Der Mangel an Bewerbungen ist bei allen Qualifikationsgruppen der Hauptgrund für die Schwierigkeit der Betriebe, offene Stellen zu besetzen. Sieben Jahre zuvor waren es hingegen vor allem fehlende Qualifikationen der Bewerber.
Bereits heute stellt jeder fünfte Betrieb der Region einen Arbeitskräfterückgang fest. Besonders spürbar ist dies in Sektoren, die auch über Stellenbesetzungsprobleme klagen: Erziehung und Unterricht, Gesundheits- und Sozialwesen, Baugewerbe. Als Reaktion auf den zunehmenden Mangel an Arbeitskräften setzen die Betriebe auf vielfältige interne und externe Maßnahmen, am häufigsten zeigen sie sich bei Einstellungen kompromissbereiter als in der Vergangenheit. Die Ausweitung betrieblicher Aus- und Weiterbildung hat hingegen als Strategie deutlich an Bedeutung verloren. Grund hierfür könnte sein, dass die entsprechenden Potenziale vielfach ausgereizt sind. Trotzdem bilden 44 Prozent der Betriebe der Region grundsätzlich aus. Von diesen ist knapp die Hälfte nicht zu Kompromissen bei der Besetzung von Ausbildungsstellen bereit. Am ehesten werden Zugeständnisse bei den schulischen Vorkenntnissen gemacht, aber auch Kompromisse bei den sozialen Qualifikationen finden sich deutlich häufiger als in der Vergangenheit. Die Gründe für die Nichtausbildung sind unterschiedlich, für die Mehrheit der nichtausbildenden Betriebe kommt eine Ausbildung jedoch generell nicht in Frage.
Beschäftigungsprognose 2015/2016 für die Region Rhein-Main :
IWAK-Betriebsbefragung im Herbst 2014
(2015)
Folgende Beschäftigungstrends in der Region Rhein-Main sind für die Jahre 2015 und 2016 zu erwarten: Die Gesamtbeschäftigung in der Region Rhein-Main wird bis Ende 2015 voraussichtlich um 1,2 Prozent steigen, was einem Zuwachs von hochgerechnet 24.500 Beschäftigten entspricht. Die Zahl der sozialversicherungspflichtig Beschäftigten steigt nach Einschätzung der Betriebe noch leicht stärker an – eine Verdrängung sozialversicherungspflichtiger Beschäftigung durch andere Beschäftigungsformen findet demnach 2015 nicht statt. Die künftige Beschäftigungsentwicklung verläuft in den Sektoren unterschiedlich. Mit einem Stellenabbau rechnet in 2015 nur das Gastgewerbe, aber auch im verarbeitenden Gewerbe und der Öffentlichen Verwaltung werden nur geringe Zuwächse erwartet. Insbesondere im Informations- und Kommunikationssektor, aber auch im Bereich der wirtschaftsnahen Dienstleistungen sowie der Sonstigen Dienstleistungen werden deutliche Beschäftigungsanstiege prognostiziert. Dies gilt überraschender Weise auch für das Baugewerbe, das den zweithöchsten Zuwachs aller Branchen erwartet. Die Unterschiede zwischen der Gesamtbeschäftigung und der sozialversicherungspflichtigen Beschäftigung sind in den Sektoren eher gering. Ein Jobmotor der Region sind erneut die sehr kleinen Betriebe, die bis Ende 2015 mit einem kräftigen Beschäftigungszuwachs rechnen. Klein- und Mittelbetriebe erwarten eher durchschnittliche Zuwächse. Anders ist dies bei den Großbetrieben, die von einer Stagnation der Gesamtbeschäftigung und einem nur leichten Zuwachs der sozialversicherungspflichtigen Beschäftigung ausgehen. Mittelfristig erwarten die Betriebe in der Region Rhein-Main eher einen weiteren Anstieg der Beschäftigung; bis Ende 2016 wird mit einem Zuwachs von zwei Prozent gerechnet. Hierbei ist aber – wie bereits bei den letztjährigen Prognosen - zu berücksichtigen, dass Prognosen über einen längeren Zeitraum auch mit höheren Unsicherheiten verbunden sind. Auch in diesem Zeithorizont rechnen die Kleinstbetriebe sowie die Dienstleistungsbetriebe, insbesondere der IuK-Sektor mit deutlich mehr Beschäftigten, während in der Öffentlichen Verwaltung sowie dem Verarbeitenden Gewerbe eine Stagnation bzw. im Finanzbereich ein leichter Rückgang der Beschäftigtenzahlen erwartet werden kann.
Die Ursachen für eine vorzeitige Lösung von Ausbildungsverträgen können vielfältig sein. Falls das Ausbildungsverhältnis gleich zu Beginn wieder gelöst wird oder der Auszubildende seine Stelle gar nicht erst antritt, liegt es nahe, die Ursachen in einer defizitären Berufsorientierung und Berufswahl auf Seiten der Jugendlichen zu suchen. Hierbei können unzureichende Kenntnisse über die Ausbildung selbst ebenso wie falsche Erwartungen an die Berufsinhalte oder auch eine mangelnde Integration in die betriebliche Praxis maßgeblich sein; auf der anderen Seite kann auch von Seiten der Betriebe eine nicht adäquate Betreuung der Auszubildenden für ein schnelles Ende des Ausbildungsverhältnisses sorgen. Die Daten des IAB-Betriebspanels Hessen 2014 belegen, dass dies ein durchaus auch quantitativ nennenswertes Problem ist: Jeder neunte im Ausbildungsjahr 2013/2014 abgeschlossene Ausbildungsvertrag wurde noch im gleichen Jahr wieder aufgelöst,
und 15 Prozent der ausbildenden Betriebe in Hessen waren von einer vorzeitigen Lösung betroffen.
Von den frei werdenden Stellen wiederum wird ein sehr kleiner Anteil nachbesetzt, der Großteil der Ausbildungsplätze bleibt vakant.Dieses Problem trifft nicht die gesamte betriebliche Ausbildungslandschaft gleichermaßen. Besonders häufig finden sich vorzeitige Vertragslösungen im Verarbeitenden Gewerbe, wo jeder fünfte Neuvertrag wieder gelöst wird, und in den kleineren betrieben Hessens mit weniger als 50 Beschäftigten. Im Bereich der wirtschaftsnahen und wissenschaftlichen Dienstleistungen kommen vorzeitige Vertragslösungen hingegen nahezu gar nicht vor, und auch in der Öffentlichen Verwaltung und den Großbetrieben werden nur selten Ausbildungsverträge gleich zu Beginn wieder aufgehoben. Die deutlichen Unterschiede belegen, dass es einer genauen Analyse der Gründe für die Vertragslösungen bedarf, die mit den Daten des IAB-Betriebspanels allerdings nicht möglich ist. Bei aller Differenziertheit der Betrachtung bleibt festzuhalten: Die vorzeitige Lösung eines abgeschlossenen Ausbildungsvertrags ist in der Regel weder für den Betrieb noch für den Auszubildenden wünschenswert. Die Anstrengungen aller Beteiligten sollten daher auf eine Vermeidung einer Vertragslösung zielen, wobei alle Phasen von der Berufsorientierung über die Berufswahl und die Einmündung in den Betrieb bis hin zur Begleitung der Ausbildung betrachtet und bei Bedarf fachlich begleitet werden sollten.
Betriebliche Ausbildung in Hessen 2014 : Stand und Entwicklung
IAB-Betriebspanel-Report Hessen
(2015)
Die Daten des IAB-Betriebspanels zeigen, dass sich die Verbreitung und die Intensität der betrieblichen Ausbildung in Hessen über die Jahre nicht massiv verändert hat. Auch 2014 ist die Ausbildungsbereitschaft ähnlich hoch wie in den Vorjahren, die Ausbildungsquote ist leicht höher als zuletzt.
Dass dies nicht Ausdruck von Stagnation ist, im Ausbildungsmarkt vielmehr große Bewegung herrscht, zeigen vor allem zwei andere Daten: Noch nie im Zeitraum der Panelbeobachtung boten die hessischen Betriebe mehr Ausbildungsstellen an und noch nie konnten so viele angebotene Stellen nicht besetzt werden wie im Jahr 2014. Die Betriebe sind demnach bereit, mehr auszubilden als in Vergangenheit; dass dies auch aufgrund der demografischen Erwartungen geschieht, liegt dabei nahe und wird von einer anderen Erkenntnis gestützt: Besonders hoch ist die Ausbildungsbeteiligung bei Betreiben, die bereits heute Schwierigkeiten bei der Rekrutierung von Fachkräften haben oder eine Überalterung der Belegschaft erwarten. Eigene Ausbildung ist hier ein quasi „natürliches“ Gegenmittel, das allerdings angesichts des zurückgehenden Potenzials an ausbildungswilligen und ausbildungsfähigen Jugendlichen ebenfalls schwieriger wird. Besonders große Schwierigkeiten, Ausbildungsstellen zu besetzen, haben wie in der Vergangenheit die kleineren Betriebe sowie Betriebe des Produzierenden Gewerbes. Dies sind Betriebe die traditionell viele Auszubildende beschäftigen, aber möglicherweise seitens der Jugendlichen gegenüber Großbetrieben und Betrieben aus dem Bereich der Öffentlichen Verwaltung weniger attraktiv gesehen werden.
Es lässt sich also festhalten: Das Bemühen der hessischen Betriebe, eigene Fachkräfte auszubilden, ist überaus groß, die hierbei auftretenden Schwierigkeiten derzeit offenkundig auch. Was von den Betrieben getan wird, um trotzdem viele Jugendliche für eine Ausbildung zu gewinnen und sie dort zu halten, wird Gegenstand des zweiten Ausbildungsreports sein.
Anfangs war die Erwartung skizziert worden, dass aufgrund der bislang nur sehr langsamen Angleichung der Beschäftigungs‐ und Karrierechancen zwischen den Geschlechtern größere Veränderungen binnen zwei Jahren eher nicht zu beobachten sein werden.
Die aktuellen Ergebnisse des IAB‐Betriebspanels bestätigen dies weitgehend: Die strukturellen Differenzen in der Beschäftigungssituation haben sich im Wesentlichen erneut gezeigt. Frauen sind in qualifizierten Tätigkeiten noch immer unterrepräsentiert, zugleich aber deutlich häufiger auf Teilzeitstellen beschäftigt oder befristet eingestellt als ihre männlichen Kollegen, zudem bleibt die Verteilung der Geschlechter auf die Sektoren sehr ungleich. Dass die Zahl der beschäftigten Frauen generell ebenso wie die Zahl der teilzeit‐ und befristet beschäftigten Frauen einen neuen Höchststand erreicht hat, ist dem generellen Beschäftigungsaufschwungs geschuldet und unterstreicht die strukturellen Differenzen eher noch. Auch bei Betrachtung der betrieblichen Führungsetagen bietet sich ein ähnliches Bild: Die Zahl der Frauen, die die höchste Hierarchiestufe erreichen, hat sich zwar erhöht, ihr Anteil liegt nahezu unverändert bei knapp einem Viertel aller Führungskräfte. Auf der zweiten Führungsebene findet sich eine deutlich größere Zahl von Frauen, aber auch hier war zuletzt kein Zuwachs mehr zu verzeichnen. Zudem konzentriert sich dies auf spezifische Wirtschaftszweige mit ohnehin hohen Frauenanteilen – im Produzierenden Gewerbe arbeiten und führen nur wenige Frauen. Nur punktuell finden sich auch Anzeichen für eine Verbesserung der Situation. So steigt in Großbetrieben der Anteil weiblicher Führungskräfte auf der zweiten Ebene kontinuierlich und deutlich, was Anlass zu der Erwartung gibt, dass dies mittelfristig auch auf der ersten Ebene wirksam wird. In mittelgroßen Betrieben ist dies bereits der Fall – dort hat sich der Anteil der Frauen auf der ersten Führungsebene in den letzten zehn Jahren mehr als verdoppelt. Die erstmals erhobene Verbreitung von Führungskräften, die ihre Aufgabe in Teilzeit wahrnehmen, liefert ebenfalls interessante Erkenntnisse. In jedem fünften hessischen Betrieb besteht diese Möglichkeit, und über 22.000 Führungskräfte machen hiervon Gebrauch. Von diesen ist immerhin ein Drittel männlich, wobei vor allem in Branchen mit vielen beschäftigten Frauen beide Geschlechter an Teilzeitführung partizipieren. Zusammengenommen zeigt dies, dass weiterhin große Anstrengungen nötig sind, wenn am Ziel einer größeren Gleichverteilung der Beschäftigungs‐ und Karrierechancen festgehalten werden soll. Zudem gibt es Anhaltspunkte, dass die stetige Etablierung von Maßnahmen zur Chancengleichheit in den betrieblichen Alltag zu deren Akzeptanz beiträgt, weshalb die gezielte Werbung und Unterstützung der Betriebe somit eine wichtige Aufgabe für die Akteure bleibt.
Die Diskussion um einen möglichen Fachkräftemangel ist in den letzten Jahren wieder stärker geworden. Aktuell berichten Betriebe verschiedener Branchen über Schwierigkeiten, geeignete Arbeits- und Fachkräfte zu finden. Hierbei bestehen jedoch deutliche Unterschiede, nicht nur zwischen einzelnen Berufsgruppen oder Branchen, sondern auch zwischen unterschiedlichen regionalen Arbeitsmärkten. Bedingt wird dies durch einen wanderungsbedingten Bevölkerungszuwachs in Ballungszentren, während ländliche und strukturschwache Regionen vermehrt von Abwanderung betroffen sind. Wie immer man den gegenwärtigen Fachkräftemangel bewertet: Absehbar ist, dass sich die genannten Entwicklungen fortsetzen und verstärken werden. Zukünftig werden - bei gleichbleibenden Bedingungen - weniger Menschen in Deutschland und Hessen leben. Damit geht unweigerlich ein Rückgang der potentiellen Erwerbspersonen einher. Gerade in den nächsten beiden Jahrzehnten scheidet eine große Anzahl an Erwerbstätigen rentenbedingt aus dem Arbeitsmarkt aus – die sogenannten geburtenstarken Nachkriegsjahrgänge. Gleichzeitig werden deutlich weniger junge Menschen auf den Arbeitsmarkt nachrücken als in der Vergangenheit, weil die Geburtenraten seit Jahren konstant niedrig sind. Nicht nur in Hessen werden sich demnach auf dem Arbeitsmarkt die Relationen von Angebot an und Nachfrage nach Arbeits- und Fachkräften verschieben. Bereits bestehende regionale Differenzen verschärfen sich dadurch vorraussichtlich noch. Um geeignete Strategien gegen drohende Arbeitskräfteengpässe zu planen und die Leistungsfähigkeit der regionalen Wirtschaft zu erhalten, bedarf es regionaldifferenzierter Informationen über die zukünftige Entwicklung auf dem hessischen Arbeitsmarkt. Derartige Daten liefert das Informations- und Prognosesystem regio pro.
Das vorliegende Papier stellt den Endbericht des Projektes „regio pro – Flächendeckende Einführung des Frühinformationssystems zur Qualifikations- und Beschäftigungsentwicklung in Hessen“ dar. Erstellt wurde der vorliegende Bericht im Dezember 2014. Der gesamte Projektzeitraum erstreckte sich vom 01.06.2011 bis zum 31.12.2014. Gefördert wird das Projekt vom Hessischen Ministerium für Wirtschaft, Energie, Verkehr und Landesentwicklung aus dem Europäischen Sozialfonds und Landesmitteln.