Hunting for Stellar Coronal Mass Ejections

Coronal mass ejections (CMEs) are explosive events that occur basically daily on the Sun. It is thought that these events play a crucial role in the angular momentum and mass loss of late-type stars, and also shape the environment in which planets form and live. Stellar CMEs can be detected in optical spectra in the Balmer lines, especially in Halpha, as blue-shifted extra emission/absorption. To increase the detection probability one can monitor young open clusters, in which the stars are due to their youth still rapid rotators, and thus magnetically active and likely to exhibit a large number of CMEs. Using ESO facilities and the Nordic Optical Telescope we have obtained time series of multi-object spectroscopic observations of late-type stars in six open clusters with ages ranging from 15 Myrs to 300 Myrs. Additionally, we have studied archival data of numerous active stars. These observations will allow us to obtain information on the occurrence rate of CMEs in late-type stars with different ages and spectral types. Here we report on the preliminary outcome of our studies.Comment: 6 pages, submitted to the proceedings of IAU Symposium 328 'Living Around Active Stars

Theoretical mass sensitivity of Love wave and layer guided acoustic plate mode sensors

A model for the mass sensitivity of Love wave and layer guided shear horizontal acoustic plate mode (SH–APM) sensors is developed by considering the propagation of shear horizontally polarized acoustic waves in a three layer system. A dispersion equation is derived for this three layer system and this is shown to contain the dispersion equation for the two layer system of the substrate and the guiding layer plus a term involving the third layer, which is regarded as a perturbing mass layer. This equation is valid for an arbitrary thickness perturbing mass layer. The perturbation, Δν, of the wave speed for the two-layer system by a thin third layer of density, ρp and thickness Δh is shown to be equal to the mass per unit area multiplied by a function dependent only on the properties of the substrate and the guiding layer, and the operating frequency of the sensor. The independence of the function from the properties of the third layer means that the mass sensitivity of the bare, two-layer, sensor operated about any thickness of the guiding layer can be deduced from the slope of the numerically or experimentally determined dispersion curve. Formulas are also derived for a Love wave on an infinite thickness substrate describing the change in mass sensitivity due to a change in frequency. The consequences of the various formulas for mass sensing applications are illustrated using numerical calculations with parameters describing a (rigid) poly(methylmethacrylate) wave-guiding layer on a finite thickness quartz substrate. These calculations demonstrate that a layer-guided SH–APM can have a mass sensitivity comparable to, or higher, than that of Love waves propagating on the same substrate. The increase in mass sensitivity of the layer guided SH–APMs over previously studied SH–APM sensors is of significance, particularly for liquid sensing applications. The relevance of the dispersion curve to experiments using higher frequencies or frequency hopping and to experiments using thick guiding layers is discussed

Nabel- und mediane Narbenhernioplastik: eine retrospektive Kohortenstudie konventioneller versus laparoskopischer Netzversorgung in der Abteilung für Allgemein- und Viszeralchirurgie der Klinik Hallerwiese Nürnberg in den Jahren 2011 bis 2013

Background Primary ventral and incisional hernia repairs are one of the most commonly conducted operations in Visceral Surgery. Many different surgical procedures including mesh implantation are available, the number of them still increasing especially with the development of minimally invasive procedures. Still there is no proved ideal, standardized method, although laparoscopic surgery is said to have advantages regarding inpatient stay, surgical site infections (SSIs) and pain. The objective of this study was to assess possible advantages of the different surgical procedures accomplished on patients with umbilical and incisional hernias of the midline in the Klinik Hallerwiese in terms of short and long term complications and results. Results The study collective (n=64) could be regarded as representative for the entire patient group (n=117). Laparoscopic umbilical hernia repair resulted in longer inpatient stay (5,8 vs. 4,6 days), more frequent intraoperative complications (2,8% (1/36) vs. 0/17 pat.) and inpatient reoperations (2,8% (1/36) vs. 0/17 pat.), as well as increased case fatality rate (2,8% (1/36) vs. 0/17 pat.). Postoperative SSIs only occurred once after open repair. Concerning long term results, as i.e. recurrence (0/16 vs. 11,1% (1/9)), chronic pain (25% (4/25) vs. 33,3% (3/16)) and post-inpatient reoperations (0/16 vs. 11,1% (1/9)) the laparoscopic procedure was advantageous. In contrast laparoscopic incisional hernia surgery showed benefits in matters of inpatient stay (8,4 vs. 9,3 days) and secondary haemorrhage (0/20 vs. 4,5% (2/44)), as well as long term complications as SSIs (0/11 vs. 10,7% (3/28)) and non-infectious wound healing disorders (0/11 vs. 7,1% (2/28)), whereas recurrences (18,2% (2/11) vs. 10,7% (3/28)), chronic pain (45,5% (5/11) vs. 32,1% (9/28)) and seromas (27,3% (3/11) vs. 21,4% (6/28)) appeared more frequently and thus more reoperations (27,3% (3/11) vs. 21,4% (6/28)) had to be performed. Patient satisfaction was superior with laparoscopic procedures in regard to most enquired parameters. All previously mentioned differences in our collective were stated as statistically non-significant. Conclusion Regarding the more difficult incisional hernia repair only short-term advantages can be stated with the laparoscopic procedure, on long term however rather disadavantages. The slightly better long time results of the laparoscopic umbilical hernia repair stood in contrast to an increased acute complication rate of an actually facile disease. Consequently the supposedly more gentle since minimally invasive methods in use with umbilical and median incisional hernias should be assessed with reserve. Ideally prospectively randomized and multicentric clinical trials with a larger patient population and longer follow-up times are required for the more reliable evaluation of laparoscopic operation methods.Hintergrund Die operative Versorgung von primären Ventral-, sowie Narbenhernien stellt eine der häufigsten Eingriffe der Abdominalchirurgie dar. Hierzu stehen zahlreiche Operationsverfahren u.a. mit Netzimplantation zur Verfügung und insbesondere durch die Weiterentwicklung minimalinvasiver Operationsmethoden kommen immer noch neue hinzu. Hierbei gibt es allerdings kein nachweislich ideales, standardisiertes Verfahren, obwohl der laparoskopischen Hernienversorgung zunehmend Vorteile hinsichtlich Wundinfektionen, Schmerzen und der stationären Aufenthaltsdauer zugeschrieben werden. Ziel der Arbeit war es, anhand der in der Klinik Hallerwiese operierten Patienten eventuelle Unterschiede der entsprechenden Operationsverfahren bezüglich verschiedener Kurz- und Langzeitkomplikationen bzw. -resultate herauszufinden. Ergebnisse Das nachuntersuchte Studienkollektiv (n=64) konnte als repräsentativ für das Gesamtkollektiv (n=117) angesehen werden. Bei der Nabelhernienversorgung resultierte das laparoskopische Vorgehen in einem längeren stationären Aufenthalt (5,8 vs. 4,6 Tagen), häufigeren intraoperativen Komplikationen (2,8% (1/36) vs. 0/17 Pat.) und stationären Reoperationen (2,8% (1/36) vs. 0/17Pat.), sowie einer erhöhten Letalität (2,8% (1/36) vs. 0/17Pat.). Eine postoperative Wundinfektion trat nur bei der konventionellen Operation auf. Bezüglich der Langzeitergebnisse, wie Rezidive (0/16 vs. 11,1% (1/9)), persistierenden Schmerzen (25% (4/16) vs. 33,3% (3/9)) sowie poststationären Reoperationen (0/16 vs. 11,1% (1/9)) war das laparoskopische Verfahren hingegen im Vorteil. Demgegenüber hatte bei der Inzisionalhernienversorgung die laparoskopische Operation Vorteile bei der Dauer des stationären Aufenthalts (8,4 vs. 9,3 Tage) und Nachblutungen (0/20 vs. 4,5% (2/44)), sowie hinsichtlich der Langzeitkomplikationen aufgrund geringerer Wundinfektionen (0/11 vs. 10,7% (3/28)) und nichtinfektiösen Wundheilungsstörungen (0/11 vs. 7,1% (2/28)), jedoch kam es häufiger zu Rezidiven (18,2% (2/11) vs. 10,7% (3/28)), persistierenden Schmerzen (45,5% (5/11) vs. 32,1% (9/28)) und Serombildung (27,3% (3/11) vs. 7,1% (2/28)) und somit häufiger zu Reoperationen (27,3% (3/11) vs. 21,4% (6/28)). Die Patientenzufriedenheit war mit dem minimalinvasiven Operationsverfahren in den allermeisten erfragten Parameter höher. Alle zuvor genannten Unterschiede der Ergebnisse waren in unserem Kollektiv statistisch nicht signifikant. Schlussfolgerung Bei der aufwändigeren Narbenhernienversorgung fielen durch die laparoskopische Technik nur kurzfristig Vorteile, auf lange Sicht allerdings Nachteile auf. Die diskret besseren Langzeitresultate bei der laparoskopischen Nabelhernioplastik wurden durch eine erhöhte Akutkomplikationsrate einer eigentlich banalen Erkrankung erkauft. Die vermeintlich schonenderen weil minimalinvasiven Methoden sind deshalb im Einsatz bei Nabel- und medianen Narbenhernien mit Zurückhaltung zu bewerten. Idealerweise prospektiv randomisiert kontrollierte und multizentrische Studien mit größeren Patientenzahlen und längerer Nachbeobachtungzeit sind zur verlässlichen Einordnung der laparoskopischen OP-Methoden notwendig

Ein zeitloser Heros: Hercules auf spätantikem Gelagegeschirr

Der alte griechische Heros Herakles erfuhr bis in die römische Kaiserzeit und Spätantike eine enorme Konjunktur. Sowohl in häuslichen Zusammenhängen als auch in der kaiserlichen Repräsentation fungierte Hercules als wichtige Referenzfigur für exemplarische virtus, Tatkraft und Stärke. Insbesondere in der Gelagekultur des 4. und 5. Jhs. n. Chr. lassen sich in Gestalt zahlreicher Hayes 53A-Trinkschalen ganze Sets nachweisen, die nicht nur die berühmten zwölf Taten des Heros zeigen, sondern, gewissermaßen als Konsequenz seines cursus honorum die Erhebung des Hercules unter die Götter suggerieren. Auch der zuvor und seit der Archaik nur selten im Bild nachweisbare Mythos wie der Kampf des Heros gegen Kyknos, der auf den Schalen mitunter gar als suggestiver Sieg des Hercules gegen Mars inszeniert wird, verdeutlicht die Zielrichtung der Bilder, die den Helden als paradigmatisches Beispiel für Unbesiegbarkeit und Kampfkraft feiern. Demgegenüber fällt auf, dass andere Episoden oder auch andere Nuancierungen des Charakters des Hercules nur in anderen Bildmedien jener Zeit, wie insbesondere auf Mosaiken, vorkommen. Im Kontrast etwa zu den ausführlichen, komplexeren biographischen Schilderungen des Mythos des Achill in der Terra Sigillata erweist sich die Verengung und Vereinfachung der Narrative um Hercules als bemerkenswert.The ancient Greek hero Herakles experienced an enormous boom up to the Roman imperial period and Late Antiquity. Both in domestic contexts and in imperial representation, Hercules functioned as an important reference figure for exemplary virtus, energy and strength. Particularly in the feast culture of the 4th and 5th century AD, entire sets can be found in the form of numerous Hayes 53A drinking bowls, which not only show the famous twelve deeds of the hero, but also, because of his cursus honorum, suggest the elevation of Hercules among the gods. Even myths that were rarely depicted before and since the Archaic period, such as the battle of the hero against Cycnus, which is sometimes even staged on the bowls as a suggestive victory of Hercules against Mars, clarify the aim of the images, which celebrate the hero as a paradigmatic example of invincibility and fighting strength. In contrast, it is striking that other episodes or even other nuances of Hercules' character only appear in other pictorial media of the time, such as mosaics in particular. In contrast, for example, to the detailed, more complex biographical descriptions of the myth of Achilles in the Terra Sigillata, the narrowing, and the simplification of the narratives around Hercules proves remarkable

What is the role of ethics in accreditation guidelines for engineering programmes in Europe?

The Washington Accord emphasises the role of ethical and societal considerations in the practice of engineering. Increasingly, national accrediting bodies are alsoexpecting to see evidence in the delivery and assessment of ethics throughoutengineering programmes. Nevertheless, there is still little known on how the process of evaluating ethics can best serve the function of accreditation ensuring quality assurance and quality improvement. The aim of this paper is to look at the top-down approach and analyse what role engineering ethics plays in national accreditation documentations in Europe. A multi-country analysis of how and where ethics appears in the systems of accreditation was carried out for the UK, Ireland, France, and Switzerland. The competencies, programme outcomes or learning outcomes were reviewed and explicit or implicit references to ethics education were identified. A quantitative and qualitative word analysis was carried out by extracting verbs and comparing verb definitions that were stated. Verbs were categorised under Doing actions, Thinking actions or both and compared to Bloom’s Taxonomy of Learning. In all cases, ethics was explicitly mentioned however limited to 1 or 2 sections of the documents reviewed. The majority of statements linking to ethics were implicit,opening room for interpretation. A more conscious effort to engage engineeringethics in all aspects of engineering programmes as well as using higher levels ofBloom’s taxonomy should be made where engineering ethics education is applied in practice

What is the role of ethics in accreditation guidelines for engineering programmes in Europe?

The Washington Accord emphasises the role of ethical and societal considerations in the practice of engineering. Increasingly, national accrediting bodies are alsoexpecting to see evidence in the delivery and assessment of ethics throughoutengineering programmes. Nevertheless, there is still little known on how the process of evaluating ethics can best serve the function of accreditation ensuring quality assurance and quality improvement. The aim of this paper is to look at the top-down approach and analyse what role engineering ethics plays in national accreditation documentations in Europe. A multi-country analysis of how and where ethics appears in the systems of accreditation was carried out for the UK, Ireland, France, and Switzerland. The competencies, programme outcomes or learning outcomes were reviewed and explicit or implicit references to ethics education were identified. A quantitative and qualitative word analysis was carried out by extracting verbs and comparing verb definitions that were stated. Verbs were categorised under Doing actions, Thinking actions or both and compared to Bloom’s Taxonomy of Learning. In all cases, ethics was explicitly mentioned however limited to 1 or 2 sections of the documents reviewed. The majority of statements linking to ethics were implicit,opening room for interpretation. A more conscious effort to engage engineeringethics in all aspects of engineering programmes as well as using higher levels ofBloom’s taxonomy should be made where engineering ethics education is applied in practice