Search for the magnetic field of the O7.5 III star xi Persei

Cyclical wind variability is an ubiquitous but as yet unexplained feature among OB stars. The O7.5 III(n)((f)) star xi Persei is the brightest representative of this class on the Northern hemisphere. As its prominent cyclical wind properties vary on a rotational time scale (2 or 4 days) the star has been already for a long time a serious magnetic candidate. As the cause of this enigmatic behavior non-radial pulsations and/or a surface magnetic field are suggested. We present a preliminary report on our attempts to detect a magnetic field in this star with high-resolution measurements obtained with the spectropolarimeter Narval at TBL, France during 2 observing runs of 5 nights in 2006 and 5 nights in 2007. Only upper limits could be obtained, even with the longest possible exposure times. If the star hosts a magnetic field, its surface strength should be less than about 300 G. This would still be enough to disturb the stellar wind significantly. From our new data it seems that the amplitude of the known non-radial pulsations has changed within less than a year, which needs further investigation.Comment: 2 pages, 6 figures, contributed poster at IAU Symposium 259 "Cosmic Magnetic Fields: from Planets, to Stars and Galaxies", Tenerife, Spain, November 3-7, 200

Organizational Communication and Burnout Symptoms

Job burnout is a psychological response to work stress. Many studies have been conducted measuring burnout and its causes and consequences. The research into causes of burnout brings up various communication-related constructs, but the relationships with feedback employees receive and communication climate is underexposed. This study investigates these relationships. Data for the current study were collected through a web-based questionnaire held among employees of a Dutch subsidiary of an international financial consultancy firm. The questionnaire included the following clusters of independent variables: (a) background variables, (b) work characteristics, (c) communication, and (d) organizational engagement. Of the four clusters of variables, the organizational engagement variables appeared to be the strongest predictors of job burnout. Still, the communication variables also made an important contribution. Particularly the communication climate and the co-worker social support appeared to be important antecedents of job burnout

Validating and optimizing the effects of model progression in simulation-based inquiry learning

Model progression denotes the organization of the inquiry learning process in successive phases of increasing complexity. This study investigated the effectiveness of model progression in general, and explored the added value of either broadening or narrowing students’ possibilities to change model progression phases. Results showed that high-school students in the ‘standard’ model progression condition (n = 19), who could enter subsequent phases at will, outperformed students from a control condition (n = 30) without model progression. The unrestricted condition (n = 22) had the additional option of returning to previous phases, whereas the restricted condition (n = 20) disallowed such downward progressions as well as upward progressions in case insufficient knowledge was acquired. Both variants were found to be more effective in terms of performance than the ‘standard’ form of model progression. However, as performance in all three model progression conditions was still rather weak, additional support is needed for students to reach full understanding of the learning content

Scanning tunnelling miscroscopy/spectroscopy and X-ray absorption spectroscopy studies of Co adatoms and anoislands on highly oriented pyrolytic graphite

In this paper, the scanning tunneling microscopy, scanning tunneling spectroscopy and X-ray absorption spectroscopy of cobalt adatoms and nanoislands were studied on a highly oriented pyrolytic graphite. Local electronic structure were observed by STS.\ud \u

Aernout van Buchel’s Iter Italicum on-line

Review of: Arnoldus Buchellius (Aernout van Buchel), Diarium (Commentarius rerum quotidianarum, including Iter Italicum). Transcription with preface and annotations of Hs. 798 (parts I and II), in the University Library of Utrech

Invasion of the Computer Culture: What You Need to Know About the New World We Live In (Book Review)

Reviewed Title: The Invasion of the Computer Culture: What You Need to Know About the New World We Live In, by Allen Emerson and Cheryl Forbes (Downers Grove, IL: Inter Varsity Press) 1989. 189 pages

Created in God\u27s Image (Book Review)

Reviewed Title: Created in God\u27s Image. Anthony A. Hoekema, Wm. B. Eerdmans Publishing Company, Grand Rapids, Michigan, 1986