Marco J. Maier

Effects of irradiation, presence of females, and sugar supply on the longevity of sterile males Aedes albopictus (Skuse) under semi-field conditions on Reunion Island.

BACKGROUND The development of the sterile insect technique (SIT) for reducing populations of Aedes albopictus (Skuse), (the vector of Chikungunya and Dengue fever), was studied in Reunion Island. For some mosquito species the sterilization process and mating activity may alter male survival. Most previous studies were carried out in the laboratory and may inadequately reflect the field situation. We conducted a semi-field experiment to evaluate the impact of sugar supply and mating activity under natural climatic conditions on wild and sterile male Ae. albopictus longevity, using large cages set up in an open clearing between trees and shrubs in Reunion Island. RESULTS Wild males had a mean longevity of 15.5 days in the absence of females and with an immediate sugar supply; longevity in sterile males was similar. The presence of females greatly reduced both wild and especially sterile male lifespan; however, an immediate sugar supply could counteract this effect and allow sterile males to live an average of 11.6 days. CONCLUSION The outcomes indicate that sugar feeding could compensate for sterilization-induced damage, and that mating activity is not deleterious for well-fed males. This study stresses the critical importance of providing suitable sugar sources prior to release during SIT programmes.

Towards a deeper understanding of managerial green investment patterns – a USA–Germany comparison

Green investments are crucial mechanisms for translating green operation strategies into managerial action. We examine the impact of external pressures on green investment patterns in terms of their scope, type and time horizon across 251 German and US managers. A scenario-based experiment was conducted using a 2 × 2 × 2 factorial design in which managers were assigned to high and low consumer, community, and resource treatment groups before being asked to make green investment decisions. Our hypotheses are developed based on resource advantage theory and tested in a number of regression models. The results demonstrate that German and US managers respond differently to external pressures in their green investment decisions. Regarding the scope of green investments, German and US managers invest differently if end consumer pressure increases and partially differently if resource scarcity increases, but they act in a similar way if community pressure increases. Moreover, we detected specific variations in the type and time horizon of green investments across US and German managers. The theoretical and practical implications of these findings for green operations management research and for firms operating in multinational settings are explained.

Die Universität – ein kohärentes Setting?

ZusammenfassungHintergrundDie vorliegende Studie untersucht das Kohärenzgefühl von Studierenden im Setting „Universität“ sowie deren subjektiv wahrgenommene Lebensqualität.MethodenEin bestehendes Instrument zur Erhebung des Kohärenzgefühls bei universitären MitarbeiterInnen wurde für Studierende adaptiert und gemeinsam mit einem Fragebogen zur subjektiven Lebensqualität 191 Studierenden an einer österreichischen Universität vorgelegt.ErgebnisseDie konfirmatorische Faktorenanalyse belegt die Dreidimensionalität der Skala zum Kohärenzgefühl von Studierenden (GFI=0,091). Der „Students‘ Sense of Coherence“ (S-SoC) hat signifikante Effekte auf die Lebensqualität.SchlussfolgerungDie Bewältigbarkeit und Sinnhaftigkeit von universitären Ereignissen sind mit dem Befinden der Befragten assoziiert. Gesundheitsförderung sollte daran setzen, klare Strukturen und mehr Mitsprachemöglichkeiten für Studierende zu schaffen.AbstractBackgroundThis study examined the sense of coherence (SOC) of students, especially for those in the university setting, as well as their perceived quality of life.MethodsA questionnaire that assesses SOC of university staff was adapted for students; 191 students at an Austrian university answered these items and questions regarding their quality of life.ResultsConfirmatory factor analysis supported the three-dimensionality of the“Students’ SoC” scale, which showed significant effects regarding the students’ quality of life.ConclusionThe manageability and meaningfulness of university events is associated with respondents’ well-being. Health promotion should implement interventions that ensure well-defined structures and more codetermination and participation for students.

Linear Logistic Models with Relaxed Assumptions in R

Linear logistic models with relaxed assumptions (LLRA) are a flexible tool for item-based measurement of change or multidimensional Rasch models. Their key features are to allow for multidimensional items and mutual dependencies of items as well as imposing no assumptions on the distribution of the latent trait in the population. Inference for such models becomes possible within a framework of conditional maximum likelihood estimation. In this paper we introduce and illustrate new functionality from the R package eRm for fitting, comparing and plotting of LLRA models for dichotomous and polytomous responses with any number of time points, treatment groups and categorical covariates.

Perspectives on Destination Competitiveness – National Destination Competitiveness’ Influence on Regional Attractiveness

Destination competitiveness as such is central for all National Tourist Offices (NTOs) and Destination Marketing Organizations (DMOs) as it is considered as the main outcome of all marketing endeavor (Pike 2008). The Osterreich Werbung (Austrian NTO) explicitly states that its main concern is “gemeinsam mit allen osterreichischen Tourismuspartnern fur den Erhalt bzw. den Ausbau der Wettbewerbsfahigkeit des Tourismuslandes Osterreich zu sorgen”1 (Osterreich Werbung 2011). In academia, Ritchie and Crouch’s (2003) notion seems to be the one other researchers agree to rely on. They argue that

Deutschlands klügste Köpfe: Was Herkunft und Hauptfach über das Allgemeinwissen aussagen

Der Beitrag vergleicht die Ergebnisse der Studierenden im Studentenpisa-Test anhand mehrerer Kriterien: dem Bundesland, in dem sie das Abitur erworben haben, dem Studienfach, das sie gewahlt haben, und der Hochschule, an der sie studieren. Welche Unterschiede gibt es zwischen Bundeslandern, Fachern und Hochschulen? Auf der Grundlage eines komplexen regressionsstatistischen Verfahrens, der so genannten Mehrebenenanalyse, zeigen sich nur geringe Unterschiede zwischen Bundeslandern, aber sehr deutliche Wissensunterschiede zwischen Studierenden verschiedener Fachrichtungen. Studierende der Politologie und der Geschichte erzielen die besten Gesamtwerte, Informatiker und Sportwissenschaftler die schlechtesten. Eine Betrachtung der Ergebnisse fur die einzelnen Wissensgebiete ergibt jedoch ein differenzierteres Bild. Demnach reflektieren die Ergebnisse die Begabung und das Interesse der Teilnehmer, welche ihren Ausdruck sowohl im Resultat des Wissenstests als auch in der Wahl einer bestimmten Studienrichtung finden.