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Methods. We analysed the energy-resolved light curve and the time-resolved X-ray spectra provided by the EPIC cameras on board XMM-Newton. We also analysed the first high-resolution spectrum of this source provided by the Reflection Grating Spectrometer. Results. An X-ray pulse of 9350 +/- 160 s was measured. Comparison with previous measurements confirms the secular spin up of this source. We successfully fit the pulse-phase-resolved spectra with Comptonisation models. These models imply a very small (r similar to 3 km) and hot (kT similar to 2-3 keV) emitting region and therefore point to a hot spot over the neutron star (NS) surface as the most reliable explanation for the X-ray pulse. The long NS spin period, the spin-up rate, and persistent X-ray emission can be explained within the theory of quasi-spherical settling accretion, which may indicate that the magnetic field is in the magnetar range. Thus, 4U0114+65 could be a wind-accreting magnetar. We also observed two episodes of low luminosity. The first was only observed in the low-energy light curve and can be explained as an absorption by a large over-dense structure in the wind of the B1 supergiant donor. The second episode, which was deeper and affected all energies, may be due to temporal cessation of accretion onto one magnetic pole caused by non-spherical matter capture from the structured stellar wind. The light curve displays two types of dips that are clearly seen during the high-flux intervals. The short dips, with durations of tens of seconds, are produced through absorption by wind clumps. The long dips, in turn, seem to be associated with the rarefied interclump medium. From the analysis of the X-ray spectra, we found evidence of emission lines in the X-ray photoionised wind of the B1Ia donor. The Fe K alpha line was found to be highly variable and much weaker than in other X-ray binaries with supergiant donors. The degree of wind clumping, measured through the covering fraction, was found to be much lower than in supergiant donor stars with earlier spectral types. Conclusions. The XMM-Newton spectroscopy provided further support for the magnetar nature of the neutron star in 4U0114+65. The light curve presents dips that can be associated with clumps and the interclump medium in the stellar wind of the mass donor.
The active ions in typical laser crystals were studied with Resonant Inelastic X-ray Scattering (RIXS) and Partial Fluorescence Yield X-ray Absorption (PFY-XAS) spectroscopies as solid state model systems for dilute active centers. We analyzed Ti3+ and Cr3+ in alpha-Al2O3:Ti3+ and LiCaAlF6:Cr3+, respectively. The comparison of experimental data with semi-empirical multiplet calculations provides insights into the electronic structure and shows how measured crystal field energies are related across different spectroscopies.
Massive runaway stars produce bow shocks through the interaction of their winds with the interstellar medium, with the prospect for particle acceleration by the shocks. These objects are consequently candidates for non-thermal emission. Our aim is to investigate the X-ray emission from these sources. We observed with XMM-Newton a sample of five bow shock runaways, which constitutes a significant improvement of the sample of bow shock runaways studied in X-rays so far. A careful analysis of the data did not reveal any X-ray emission related to the bow shocks. However, X-ray emission from the stars is detected, in agreement with the expected thermal emission from stellar winds. On the basis of background measurements we derive conservative upper limits between 0.3 and 10 keV on the bow shocks emission. Using a simple radiation model, these limits together with radio upper limits allow us to constrain some of the main physical quantities involved in the non-thermal emission processes, such as the magnetic field strength and the amount of incident infrared photons. The reasons likely responsible for the non-detection of non-thermal radiation are discussed. Finally, using energy budget arguments, we investigate the detectability of inverse Compton X-rays in a more extended sample of catalogued runaway star bow shocks. From our analysis we conclude that a clear identification of non-thermal X-rays from massive runaway bow shocks requires one order of magnitude (or higher) sensitivity improvement with respect to present observatories.
WR 148 (HD 197406) is an extreme runaway system considered to be a potential candidate for a short-period (4.3173 d) rare WR + compact object binary. Provided with new high-resolution, high signal-to-noise spectra from the Keck observatory, we determine the orbital parameters for both the primary WR and the secondary, yielding respective projected orbital velocity amplitudes of 88.1 ± 3.8 km s−1 and 79.2 ± 3.1 km s−1 and implying a mass ratio of 1.1 ± 0.1. We then apply the shift-and-add technique to disentangle the spectra and obtain spectra compatible with a WN7ha and an O4-6 star. Considering an orbital inclination of ∼67°, derived from previous polarimetry observations, the system's total mass would be a mere 2–3M⊙⁠, an unprecedented result for a putative massive binary system. However, a system comprising a 37M⊙ secondary (typical mass of an O5V star) and a 33M⊙ primary (given the mass ratio) would infer an inclination of ∼18°. We therefore reconsider the previous methods of deriving the orbital inclination based on time-dependent polarimetry and photometry. While the polarimetric results are inconclusive requiring better data, the photometric results favour low inclinations. Finally, we compute WR 148’s space velocity and retrace the runaway's trajectory back to the Galactic plane (GP). With an ejection velocity of 198 ± 27 km s−1 and a travel time of 4.7 ± 0.8 Myr to reach its current location, WR 148 was most likely ejected via dynamical interactions in a young cluster.
Work-anxieties are costly and need early intervention. The perception of being able to cope with work is a basic requirement for work ability. This randomized controlled trial investigates whether a cognitive behavioural, work-anxiety-coping group (WAG) intervention leads to better work-coping perception than an unspecific recreational group (RG). Heterogeneous people in medical rehabilitation, who were due to return to work, were interviewed concerning their work-anxieties, and either randomly assigned to a WAG (n=85) or a RG (n=95). The participants (with an average of 50years old [range 23-64]; 51% women; 70% workers or employees, 25% academics, 5% unskilled) followed the group intervention for four or six sessions. The perceived work-coping was assessed by self-rating (Inventory for Job-Coping and Return Intention JoCoRi) after each group session. Although participants had a slight temporary decrease in work-coping after group session two (from M-1=2.47 to M-2=2.28, d(Cohen)=-.22), the WAG led to the improvement of perceived work-coping over the intervention course (from M-1=2.47 to M-6=2.65, d(Cohen)=.18). In contrast, participants from the RG reported lower work-coping after six group sessions (from M-1=2.26 to M-6=2.02, d(Cohen)=-.18). It is considered that people with work-anxieties need training in work-coping. By focusing on recreation only, this may lead to deterioration of work-coping. Indeed, intervention designers should be aware of temporary deterioration (side effects) when confronting participants with work-coping.
word-object mappings
(2017)
This study set out to examine whether shyness, an aversion to novelty and unfamiliar social situations, can affect the processes that underlie early word learning. Twenty-four-month-old children (n =32) were presented with sets of one novel and two familiar objects, and it was found that shyer children were less likely to select a novel object as the referent of a novel label. Furthermore, not-shy children then showed evidence of retaining these novel mappings, but shy children did not. These findings suggest that shy children's aversion to novelty and to the unfamiliar context can impact on their word learning.
Electrophysiological research using verbal response paradigms faces the problem of muscle artifacts that occur during speech production or in the period preceding articulation. In this context, this paper has two related aims. The first is to show how the nature of the first phoneme influences the alignment of the ERPs. The second is to further characterize the EEG signal around the onset of articulation, both in temporal and frequency domains. Participants were asked to name aloud pictures of common objects. We applied microstate analyses and time-frequency transformations of ERPs locked to vocal onset to compare the EEG signal between voiced and unvoiced labial plosive word onset consonants. We found a delay of about 40 ms in the set of stable topographic patterns for /b/ relative to /p/ onset words. A similar shift was observed in the power increase of gamma oscillations (30-50 Hz), which had an earlier onset for /p/ trials (similar to 150 ms before vocal onset). This 40-ms shift is consistent with the length of the voiced proportion of the acoustic signal prior to the release of the closure in the vocal responses. These results demonstrate that phonetic features are an important parameter affecting response-locked ERPs, and hence that the onset of the acoustic energy may not be an optimal trigger for synchronizing the EEG activity to the response in vocal paradigms. The indexes explored in this study provide a step forward in the characterization of muscle-related artifacts in electrophysiological studies of speech and language production.
The integration of balance and plyometric training has been shown to provide significant improvements in sprint, jump, agility, and other performance measures in young athletes. It is not known if a specific within session balance and plyometric exercise sequence provides more effective training adaptations. The objective of the present study was to investigate the effects of using a sequence of alternating pairs of exercises versus a block (series) of all balance exercises followed by a block of plyometric exercises on components of physical fitness such as muscle strength, power, speed, agility, and balance. Twenty-six male adolescent soccer players ( 13.9 +/- 0.3 years) participated in an 8-week training program that either alternated individual balance (e. g., exercises on unstable surfaces) and plyometric (e. g., jumps, hops, rebounds) exercises or performed a block of balance exercises prior to a block of plyometric exercises within each training session. Pre- and post-training measures included proxies of strength, power, agility, sprint, and balance such as countermovement jumps, isometric back and knee extension strength, standing long jump, 10 and 30-m sprints, agility, standing stork, and Y-balance tests. Both groups exhibited significant, generally large magnitude (effect sizes) training improvements for all measures with mean performance increases of approximately > 30%. There were no significant differences between the training groups over time. The results demonstrate the effectiveness of combining balance and plyometric exercises within a training session on components of physical fitness with young adolescents. The improved performance outcomes were not significantly influenced by the within session exercise sequence.
Winter precipitation forecast in the European and mediterranean regions using cluster analysis
(2017)
The European climate is changing under global warming, and especially the Mediterranean region has been identified as a hot spot for climate change with climate models projecting a reduction in winter rainfall and a very pronounced increase in summertime heat waves. These trends are already detectable over the historic period. Hence, it is beneficial to forecast seasonal droughts well in advance so that water managers and stakeholders can prepare to mitigate deleterious impacts. We developed a new cluster-based empirical forecast method to predict precipitation anomalies in winter. This algorithm considers not only the strength but also the pattern of the precursors. We compare our algorithm with dynamic forecast models and a canonical correlation analysis-based prediction method demonstrating that our prediction method performs better in terms of time and pattern correlation in the Mediterranean and European regions.
The strength of the North Atlantic Oscillation (NAO) is considered to be the main driver of climate changes over the European and western Asian continents throughout the last millennium. For example, the predominantly warm Medieval Climate Anomaly (MCA) and the following cold period of the Little Ice Age (LIA) over Europe have been associated with long-lasting phases with a positive and negative NAO index. Its climatic imprint is especially pronounced in European winter seasons. However, little is known about the influence of NAO with respect to its eastern extent over the Eurasian continent. Here we present speleothem records (PC, 8180 and Sr/Ca) from the southern rim of Fergana Basin (Central Asia) revealing annually resolved past climate variations during the last millennium. The age control of the stalagmite relies on radiocarbon dating as large amounts of detrital material inhibit accurate 230Th dating. Present-day calcification of the stalagmite is most effective during spring when the cave atmosphere and elevated water supply by snow melting and high amount of spring precipitation provide optimal conditions. Seasonal precipitation variations cause changes of the stable isotope and Sr/ Ca compositions. The simultaneous changes in these geochemical proxies, however, give also evidence for fractionation processes in the cave. By disentangling both processes, we demonstrate that the amount of winter precipitation during the MCA was generally higher than during the LIA, which is in line with climatic changes linked to the NAO index but opposite to the higher mountain records of Central Asia. Several events of strongly reduced winter precipitation are observed during the LIA in Central Asia. These dry winter events can be related to phases of a strong negative NAO index and all results reveal that winter precipitation over the central Eurasian continent is tightly linked to atmospheric NAO modes by the westerly wind systems. (C) 2017 Elsevier Ltd. All rights reserved.
Wings of the butterfly
(2017)
The spatio-temporal evolution of sunspot activity, the so-called Maunder butterfly diagram, has been continously available since 1874 using data from the Royal Greenwich Observatory, extended by SOON network data after 1976. Here we present a new extended butterfly diagram of sunspot group occurrence since 1826, using the recently digitized data from Schwabe (1826-1867) and Sporer (1866-1880). The wings of the diagram are separated using a recently developed method based on an analysis of long gaps in sunspot group occurrence in different latitude bands. We define characteristic latitudes, corresponding to the start, end, and the largest extent of the wings (the F, L, and H latitudes). The H latitudes (30 degrees-45 degrees) are highly significantly correlated with the strength of the wings (quantified by the total sum of the monthly numbers of sunspot groups). The F latitudes (20 degrees-30 degrees) depict a weak tendency, especially in the southern hemisphere, to follow the wing strength. The L latitudes (2 degrees-10 degrees) show no clear relation to the wing strength. Overall, stronger cycle wings tend to start at higher latitudes and have a greater wing extent. A strong (5-6)-cycle periodic oscillation is found in the start and end times of the wings and in the overlap and gaps between successive wings of one hemisphere. While the average wing overlap is zero in the southern hemisphere, it is two to three months in the north. A marginally significant oscillation of about ten solar cycles is found in the asymmetry of the L latitudes. The new long database of butterfly wings provides new observational constraints to solar dynamo models that discuss the spatio-temporal distribution of sunspot occurrence over the solar cycle and longer.
The objective of this study was to determine the relationship between having a special educational needs background (SEN) and the likelihood of having friends in inclusive classes. We assumed that a combination of individual, dyadic and contextual variables can sufficiently explain the relation between a SEN diagnosis and the likelihood of friendship. Data analysis was based on a cross-sectional sample of students (N = 1241) in second and third grade primary-school classes. To address the different levels adequately, the present study improves upon previous research in two ways: First, the sociometric data were analyzed with the p2 model, a specialized multilevel network model. Second, the study focused solely on friendships and emphasized the concept’s unique features with respect to inclusive education. Data analysis indicated that students with SEN had a decreased probability of becoming friends with their classmates compared to students without SEN. Even when individual, dyadic, and contextual variables were included into the model, the association between a SEN diagnosis and the likelihood of friendship persisted. The implications of the results are discussed with respect to their implications for inclusive teaching practice.
Theoretischer Hintergrund: Einflüsse von therapeutenorientiertem Kompetenz-Feedback in der Psychotherapieausbildung wurden bislang wenig untersucht.
Fragestellung: Wie gehen Ausbildungstherapeuten mit Feedback um? Welchen Einfluss hat ein regelmäßiges Kompetenz-Feedback auf die Qualität psychotherapeutischer Behandlungen (insbesondere Therapiesitzungen, therapeutische Beziehung, Person des Therapeuten, Supervision)?
Methode: Elf Therapeuten wurden mithilfe eines halbstrukturierten Interviewleitfadens befragt. Die Auswertung erfolgte mittels qualitativer Inhaltsanalyse nach Mayring (2015).
Ergebnisse: Das auf Basis der Interviews erstellte Kategoriensystem umfasste die Kategorien „Erwartungen an das Feedback“, „Wahrnehmung des Feedbacks“, „Verarbeitung von und Umgang mit Feedback“, „Folgen, Auswirkungen und Veränderungen durch Feedback“ sowie „Verbesserungswünsche“.
Schlussfolgerungen: Therapeuten streben eine Umsetzung des Feedbacks an, welches sich auf die Behandlung, die Supervision, die eigene Person und die therapeutische Beziehung auswirkt.
Theoretischer Hintergrund: Einflüsse von therapeutenorientiertem Kompetenz-Feedback in der Psychotherapieausbildung wurden bislang wenig untersucht.
Fragestellung: Wie gehen Ausbildungstherapeuten mit Feedback um? Welchen Einfluss hat ein regelmäßiges Kompetenz-Feedback auf die Qualität psychotherapeutischer Behandlungen (insbesondere Therapiesitzungen, therapeutische Beziehung, Person des Therapeuten, Supervision)?
Methode: Elf Therapeuten wurden mithilfe eines halbstrukturierten Interviewleitfadens befragt. Die Auswertung erfolgte mittels qualitativer Inhaltsanalyse nach Mayring (2015).
Ergebnisse: Das auf Basis der Interviews erstellte Kategoriensystem umfasste die Kategorien „Erwartungen an das Feedback“, „Wahrnehmung des Feedbacks“, „Verarbeitung von und Umgang mit Feedback“, „Folgen, Auswirkungen und Veränderungen durch Feedback“ sowie „Verbesserungswünsche“.
Schlussfolgerungen: Therapeuten streben eine Umsetzung des Feedbacks an, welches sich auf die Behandlung, die Supervision, die eigene Person und die therapeutische Beziehung auswirkt.
Kurz vor ihrem sechzigsten Geburtstag ist die europäische Union mit inneren und äußeren Herausforderungen konfrontiert und befindet sich in einer tiefen Krise. Am 1. März 2017 legte Kommissionspräsident Juncker das „Weißbuch über die Zukunft der Europäischen Union“ vor, in dem er verschiedene Szenarien darlegt und zur Diskussion über die anste-henden Entscheidungen einlädt. Diese Papier versteht sich als ein solcher Diskussionsbei-trag.
Im kognitiven Vulnerabilitäts-Stress-Modell der Depression von A.T. Beck (1967, 1976) spielen dysfunktionale Einstellungen bei der Entstehung von Depression in Folge von erlebtem Stress eine zentrale Rolle. Diese Theorie prägt seit Jahrzehnten die ätiologische Erforschung der Depression, jedoch ist die Bedeutung dysfunktionaler Einstellungen im Prozess der Entstehung einer Depression insbesondere im Kindes- und Jugendalter nach wie vor unklar. Die vorliegende Arbeit widmet sich einigen in der bisherigen Forschung wenig behandelten Fragen. Diese betreffen u. a. die Möglichkeit nichtlinearer Effekte dysfunktionaler Einstellungen, Auswirkungen einer Stichprobenselektion, Entwicklungseffekte sowie die Spezifität etwaiger Zusammenhänge für eine depressive Symptomatik.
Zur Beantwortung dieser Fragen wurden Daten von zwei Messzeitpunkten der PIER-Studie, eines großangelegten Längsschnittprojekts über Entwicklungsrisiken im Kindes- und Jugendalter, genutzt. Kinder und Jugendliche im Alter von 9 bis 18 Jahren berichteten zweimal im Abstand von ca. 20 Monaten im Selbstberichtsverfahren über ihre dysfunktionalen Einstellungen, Symptome aus verschiedenen Störungsbereichen sowie über eingetretene Lebensereignisse.
Die Ergebnisse liefern Evidenz für ein Schwellenmodell, in dem dysfunktionale Einstellungen unabhängig von Alter und Geschlecht nur im höheren Ausprägungsbereich eine Wirkung als Vulnerabilitätsfaktor zeigen, während im niedrigen Ausprägungsbereich keine Zusammenhänge zur späteren Depressivität bestehen. Eine Wirkung als Vulnerabilitätsfaktor war zudem nur in der Subgruppe der anfänglich weitgehend symptomfreien Kinder und Jugendlichen zu beobachten. Das Schwellenmodell erwies sich als spezifisch für eine depressive Symptomatik, es zeigten sich jedoch auch (teilweise ebenfalls nichtlineare) Effekte dysfunktionaler Einstellungen auf die Entwicklung von Essstörungssymptomen und aggressivem Verhalten. Bei 9- bis 13-jährigen Jungen standen dysfunktionale Einstellungen zudem in Zusammenhang mit einer Tendenz, Stress in Leistungskontexten herbeizuführen.
Zusammen mit den von Sahyazici-Knaak (2015) berichteten Ergebnissen aus der PIER-Studie weisen die Befunde darauf hin, dass dysfunktionale Einstellungen im Kindes- und Jugendalter – je nach betrachteter Subgruppe – Ursache, Symptom und Konsequenz der Depression darstellen können. Die in der vorliegenden Arbeit gezeigten nichtlinearen Effekte dysfunktionaler Einstellungen und die Effekte der Stichprobenselektion bieten eine zumindest teilweise Erklärung für die Heterogenität früherer Forschungsergebnisse. Insgesamt lassen sie auf komplexe – und nicht ausschließlich negative – Auswirkungen dysfunktionaler Einstellungen schließen. Für eine adäquate Beurteilung der „Dysfunktionalität“ der von A.T. Beck so betitelten Einstellungen erscheint daher eine Berücksichtigung der betrachteten Personengruppe, der absoluten Ausprägungen und der fraglichen Symptomgruppen geboten.
Recent reports of increasing iron (Fe) concentrations in freshwaters are of concern, given the fundamental role of Fe in biogeochemical processes. Still, little is known about the frequency and geographical distribution of Fe trends or about the underlying drivers. We analyzed temporal trends of Fe concentrations across 340 water bodies distributed over 10 countries in northern Europe and North America in order to gain a clearer understanding of where, to what extent, and why Fe concentrations are on the rise. We found that Fe concentrations have significantly increased in 28% of sites, and decreased in 4%, with most positive trends located in northern Europe. Regions with rising Fe concentrations tend to coincide with those with organic carbon (OC) increases. Fe and OC increases may not be directly mechanistically linked, but may nevertheless be responding to common regional-scale drivers such as declining sulfur deposition or hydrological changes. A role of hydrological factors was supported by covarying trends in Fe and dissolved silica, as these elements tend to stem from similar soil depths. A positive relationship between Fe increases and conifer cover suggests that changing land use and expanded forestry could have contributed to enhanced Fe export, although increases were also observed in nonforested areas. We conclude that the phenomenon of increasing Fe concentrations is widespread, especially in northern Europe, with potentially significant implications for wider ecosystem biogeochemistry, and for the current browning of freshwaters.