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We investigated the interaction of a coronal mass ejection (CME) and a coronal hole (CH) in its vicinity using remote-sensing and 1 AU in situ data. We used extreme-ultraviolet images and magnetograms to identify coronal structures and coronagraph images to analyze the early CME propagation. The Wind spacecraft and the Advanced Composition Explorer (ACE) provide plasma and magnetic field data of near-Earth interplanetary space. We applied various diagnostic tools to the images and to the time-series data. We find that the CME erupts under a streamer and causes the evacuation of material at its far end, which is observable as dimming and subsequent CH formation. The CME is likely deflected in its early propagation and travels southwest of the Sun-Earth line. In situ data lack signatures of a large magnetic cloud, but show a small flux rope at the trailing edge of the interplanetary CME (ICME), followed by an Alfvénic wave. This wave is identified as exhaust from a Petschek-type reconnection region following the successful application of a Walén test. We infer that the two spacecraft at 1 AU most likely traverse the ICME leg that is in the process of reconnection along the heliospheric current sheet that separates the ICME and the high-speed stream outflowing from the CH.

The interaction of interplanetary coronal mass ejections (ICMEs) and stream interaction regions (SIRs) gives rise to complex heliospheric plasma and magnetic field conditions. Considering the different magnetic configurations of both phenomena as well as the source regions in the solar corona, there is also the possibility of magnetic reconnection either at coronal heights or farther out in the heliosphere.The event of February 7th, 2014 shows clear signatures of a qualitative alteration of the ICME structure in ACE plasma and magnetic field data. There is a significant drop of the magnetic field strength inside the FR simultaneously to an enhancement in temperature and a high variability of speed. The flow angle reversal expected to take place at the stream interface sharply coincides with the onset of the ICME magnetic field rotations and drop of temperature below expected temperature. The speed inside the flux rope, yet showing the aforementioned variations, overall features a decline from the front to the rear of the ICME. The launch site of the ICME is derived from SDO AIA data, showing its location to be 30° West from a N-S elongated coronal hole.These results imply a deterioration of the FR due to magnetic reconnection, either caused by the proximity of CH and CME eruption site and favorable magnetic configurations, or the heliospheric interaction of the associated SIR and ICME. WSA-ENLIL simulations suggest that the ICME catches up with the SIR close to Earth, which, along with the in-situ signatures, implies the simultaneous occurrence of stream interface and flux rope onset. The declining speed profile that is characteristic for quiescent ICME spatial evolution suggests no high-speed stream is inhibiting expansion from behind. Due to its complexity, this event provides a great opportunity to study the interaction of ICMEs and SIRs.

Magnetosheath jets constitute a significant coupling effect between the solar wind (SW) and the magnetosphere of the Earth. In order to investigate the effects and forecasting of these jets, we present the first-ever statistical study of the jet production during large-scale SW structures like coronal mass ejections (CMEs), stream interaction regions (SIRs) and high speed streams (HSSs). Magnetosheath data from Time History of Events and Macroscale Interactions during Substorms (THEMIS) spacecraft between January 2008 and December 2020 serve as measurement source for jet detection. Two different jet definitions were used to rule out statistical biases induced by our jet detection method. For the CME and SIR + HSS lists, we used lists provided by literature and expanded on incomplete lists using OMNI data to cover the time range of May 1996 to December 2020. We find that the number and total time of observed jets decrease when CME-sheaths hit the Earth. The number of jets is lower throughout the passing of the CME-magnetic ejecta (ME) and recovers quickly afterward. On the other hand, the number of jets increases during SIR and HSS phases. We discuss a few possibilities to explain these statistical results.

The purpose of this study is to examine the prevalence of different workplace accommodation request strategies, the effectiveness of different request approaches, and situational and individual factors associated with different request strategies for individuals with disabilities. Common action plans of accommodation requests may vary depending on decisions about mentioning the Americans With Disabilities Act (ADA) (or not) and whether a formal (or informal) request is submitted, though past literature has focused primarily on formal accommodation requests made under the auspices of the ADA. Participants ( n = 408) were recruited from rehabilitation agencies and organizations serving people with disabilities in the United States. The results indicated that informal requests without mentioning the ADA were found most often, followed by formal requests while not mentioning the ADA, formal requests while mentioning the ADA, and informal requests while mentioning the ADA. The odds of acquiring the requested accommodation were significantly higher, relative to other strategies, for requests made informally without mentioning the ADA. A variety of individual attributes capable of discerning when participants chose one strategy over another were observed; these included self-efficacy and outcome expectancy, negative affect, and an array of situational and personal attributes. Implications for research and practice were discussed.

We inspect the evolution of stream interaction regions from Earth to Mars for the declining solar cycle 24. In particular, the opposition phases of the two planets are analyzed in more detail. So far, there is no study comparing the long-term properties of stream interaction regions and accompanying high-speed streams at both planets for the same time period. We build a catalogue covering a dataset of all measured stream interaction regions at Earth and Mars for the time period December 2014 – November 2018. The number of events (>120) allows for a strong statistical basis. To build the catalogue we use near-earth OMNI data as well as measurements from the Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft. For the opposition phase, we additionally use image data from the Solar Dynamics Observatory to complement the in-situ observations. Bulk speed, proton density, temperature, magnetic field magnitude and total perpendicular pressure are statistically evaluated using a superposed epoch analysis. For the opposition phase, coronal holes that are linked to individual streams are identified. The extracted coronal hole areas (using CATCH) and their longitudinal/latitudinal extension are correlated to the duration and maximum bulk speed of the high-speed stream following the passage of a stream interaction region. We find that an expansion of the stream interface from 1 to 1.5 AU is most visible in magnetic field and total perpendicular pressure. The duration of the high-speed stream does not increase significantly from Earth to Mars, however, the stream crest seems to increase. The amplitudes of the SW parameters are found to only slightly increase or stagnate from 1 – 1.5 AU. We arrive at similar correlation coefficients for both planets with the properties of the related coronal holes. There is a stronger linking of maximum bulk speed to latitudinal extent of the coronal hole than to the longitudinal. On average, the occurrence rate of fast forward shocks increases from Earth to Mars.

We inspect the evolution of SIRs from Earth to Mars (distance range 1-1.5 AU) over the declining phase of solar cycle 24 (2014-2018). So far, studies only analyzed SIRs measured at Earth and Mars at different times. We compare existing catalogs for both heliospheric distances and arrive at a clean dataset for the identical time range. This allows a well-sampled statistical analysis and for the opposition phases of the planets an in-depth analysis of SIRs as they evolve with distance. We use in-situ solar wind data from OMNI and the MAVEN spacecraft as well as remote sensing data from SDO. A superposed epoch analysis is performed for bulk speed, proton density, temperature, magnetic field magnitude and total perpendicular pressure. Additionally, a study of events during the two opposition phases of Earth and Mars in the years 2016 and 2018 is conducted. SIR related coronal holes with their area as well as their latitudinal and longitudinal extent are extracted and correlated to the maximum bulk speed and duration of the corresponding high speed solar wind streams following the stream interaction regions. We find that while the entire solar wind HSS shows no expansion as it evolves from Earth to Mars, the crest of the HSS profile broadens by about 17%, and the magnetic field and total pressure by about 45% around the stream interface. The difference between the maximum and minimum values in the normalized superposed profiles increases slightly or stagnates from 1-1.5 AU for all parameters, except for the temperature. A sharp drop at zero epoch time is observed in the superposed profiles for the magnetic field strength at both heliospheric distances. Maximum solar wind speed has a stronger dependence on the latitudinal extent of the respective coronal hole than on its longitudinal extent. We arrive at an occurrence rate of fast forward shocks three times as high at Mars than at Earth., Comment: Accepted for Publication in A&A

The cultural turn of the 1980s led to a kind of self-sociologicization in many areas of the former ‘liberal arts and humanities’ (Geisteswissenschaften) and, particularly, in the (ancient) philologies. The findings of the so-called cultural studies will, however, only be met with a weary smile by genuine sociologists. One superficial paradigm shift is followed by another, each producing new, arbitrary descriptions lacking any standard of relevance—descriptions whose regulatory idea is a vague notion of diversity. The corresponding self-inflicted marginalization of cultural studies can only be rectified by an epistemological break from the dominant, simplistic, symbolic-interactionist notion of culture. The hypocritical notion of critique in cultural studies must undergo a transcendental critique that undoes the dedifferentiation of the concepts ‘culture’ and ‘civilization’. By this way, the futile ‘cultural studies’ will become a future ‘science of culture’.

Montesquieu, der Begrunder der modernen (Rechts-)Soziologie, gibt in seinem Hauptwerk De l’Esprit des Loix (Vom Geist der Gesetze) (1748) auch eine moderne, wissenschaftliche Fassung des Geist-Begriffes. Ausgehend von den positiv geltenden Gesetzen verschiedener Gesellschaften zu verschiedenen Zeiten und an verschiedenen Orten entwirft er eine soziale Typenlehre und fragt nach den materiellen (beispielsweise Klima) und ideellen (wie Religion und Gebrauche) Bedingungen fur die Herausbildung eines bestimmten sozialen Typus. Diese Bedingungen synthetisiert er dann zum ›Geist‹ der Gesetze einer bestimmten Gesellschaft, was man frei auch mit ihrem kollektiven Bewusstsein oder der herrschenden Mentalitat wiedergeben konnte.

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Für die vorliegende Arbeit sind als Korpus die drei folgenden Romane aus unterschiedlichen Schaffensphasen des Autors Luigi Pirandello relevant: Il fu Mattia Pascal von 1904, Quaderni di Serafino Gubbio operatore von 1915 und Uno, nessuno e centomila von 1925. Diese Romane werden in der Pirandelloforschung als Trilogie gelesen, so auch hier. Die theoretische Grundlage bildet das Kapitel zu Pirandellos Aufsatz L’Umorismo, welches der Analyse vorangestellt ist. Dabei wird „umorismo“ in der Bedeutung einer Denkfigur verstanden, die als prä-existenzialistische Theorie gelesen werden kann. Unter diesem Aspekt erfolgt auch die Analyse des Korpus . Dabei wird gezeigt, dass Pirandello seine Theorie ebenso literarisch abbildet, wie die Existenzialisten Sartre und Camus. Die thematische Nähe, die zwischen Pirandello, Sartre und Camus besteht, ist an entsprechender Stelle herausgearbeitet.

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