29 research outputs found
Die "Jenaer Erklärung" als Herausforderung und Chance für eine rassismussensible Bildungsarbeit
Die deutsche Wiedervereinigung und ihr Einfluss auf die Darstellung der Evolutionsbiologie im Biologielehrbuch der Klasse 10 aus dem Verlag Volk und Wissen
Schoolbook research is in particular topical after radical political changes and if it concerns the reputation of the publisher (cp. Pöggeler 2003). Both were the case in 1989 due to political and social changes on the territory of the German Democratic Republic (GDR), which ultimately led to changes in the socially favored values and standard notions as well. Since schoolbooks and curricula are subject to governmental influences (cp. Wiater 2006), the question of modifications in the presentation of the subjects arises. The aim of this analysis is, in the context of social political transformation, the amendment of aim, context and presentation in biology schoolbooks of the publishing house Volk und Wissen, using the example of 10th grade evolutionary biology. For that purpose relevant schoolbooks were, in the context of a quantitative analysis of the content, evaluated product-oriented. The analysis of the computer-based transliterated schoolbooks was carried out via QDA-Software based on an open encoding process. To broaden the understanding, additional material will be used for the explication of relevant contents (broad content analysis). In particular this refers to the presentation of ideologies, which are according to Berck and Graf (2010) present in biology schoolbooks in the majority of cases. In the concluding discussion the impact of the social change on the chosen educational media is pointed out to eventually contribute to “a better understanding of the school as broadcaster of knowledge in the society” (Depaepe/Simon 2003, p. 66). (DIPF/Orig.
Unterrichtsprojekt "(Anti-)Rassismus - Wir begeben uns auf eine Zeitreise!"
Chelsea Vogel, Uwe Hoßfeld und Karl Porges fragen, wie sich (Anti-)Rassismus im Biologieunterricht behandeln lässt und bieten die Idee, mithilfe eines Workbooks die Lernenden auf eine Zeitreise mitzunehmen. (DIPF/Orig.
Frequency drift in MR spectroscopy at 3T
Purpose: Heating of gradient coils and passive shim components is a common cause of instability in the B-0 field, especially when gradient intensive sequences are used. The aim of the study was to set a benchmark for typical drift encountered during MR spectroscopy (MRS) to assess the need for real-time field-frequency locking on MRI scanners by comparing field drift data from a large number of sites.Method: A standardized protocol was developed for 80 participating sites using 99 3T MR scanners from 3 major vendors. Phantom water signals were acquired before and after an EPI sequence. The protocol consisted of: minimal preparatory imaging; a short pre-fMRI PRESS; a ten-minute fMRI acquisition; and a long post-fMRI PRESS acquisition. Both pre- and post-fMRI PRESS were non-water suppressed. Real-time frequency stabilization/adjustment was switched off when appropriate. Sixty scanners repeated the protocol for a second dataset. In addition, a three-hour post-fMRI MRS acquisition was performed at one site to observe change of gradient temperature and drift rate. Spectral analysis was performed using MATLAB. Frequency drift in pre-fMRI PRESS data were compared with the first 5:20 minutes and the full 30:00 minutes of data after fMRI. Median (interquartile range) drifts were measured and showed in violin plot. Paired t-tests were performed to compare frequency drift pre- and post-fMRI. A simulated in vivo spectrum was generated using FID-A to visualize the effect of the observed frequency drifts. The simulated spectrum was convolved with the frequency trace for the most extreme cases. Impacts of frequency drifts on NAA and GABA were also simulated as a function of linear drift. Data from the repeated protocol were compared with the corresponding first dataset using Pearson's and intraclass correlation coefficients (ICC).Results: Of the data collected from 99 scanners, 4 were excluded due to various reasons. Thus, data from 95 scanners were ultimately analyzed. For the first 5:20 min (64 transients), median (interquartile range) drift was 0.44 (1.29) Hz before fMRI and 0.83 (1.29) Hz after. This increased to 3.15 (4.02) Hz for the full 30 min (360 transients) run. Average drift rates were 0.29 Hz/min before fMRI and 0.43 Hz/min after. Paired t-tests indicated that drift increased after fMRI, as expected (p < 0.05). Simulated spectra convolved with the frequency drift showed that the intensity of the NAA singlet was reduced by up to 26%, 44 % and 18% for GE, Philips and Siemens scanners after fMRI, respectively. ICCs indicated good agreement between datasets acquired on separate days. The single site long acquisition showed drift rate was reduced to 0.03 Hz/min approximately three hours after fMRI.Discussion: This study analyzed frequency drift data from 95 3T MRI scanners. Median levels of drift were relatively low (5-min average under 1 Hz), but the most extreme cases suffered from higher levels of drift. The extent of drift varied across scanners which both linear and nonlinear drifts were observed.</p
The James Webb Space Telescope Mission
Twenty-six years ago a small committee report, building on earlier studies,
expounded a compelling and poetic vision for the future of astronomy, calling
for an infrared-optimized space telescope with an aperture of at least .
With the support of their governments in the US, Europe, and Canada, 20,000
people realized that vision as the James Webb Space Telescope. A
generation of astronomers will celebrate their accomplishments for the life of
the mission, potentially as long as 20 years, and beyond. This report and the
scientific discoveries that follow are extended thank-you notes to the 20,000
team members. The telescope is working perfectly, with much better image
quality than expected. In this and accompanying papers, we give a brief
history, describe the observatory, outline its objectives and current observing
program, and discuss the inventions and people who made it possible. We cite
detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space
Telescope Overview, 29 pages, 4 figure
Lespedeza virginica Britton.
https://thekeep.eiu.edu/herbarium_specimens_byname/6026/thumbnail.jp
Lespedeza virginica Britton.
https://thekeep.eiu.edu/herbarium_specimens_byname/6026/thumbnail.jp
Die Evokids-Boxen im Praxistest. Ein didaktisch-methodisches Konzept für einen inklusiven Unterricht
In 2015, the 2nd Evokids Congress was held in Gießen. The meeting adopted a resolution for a stronger consideration of evolutionary biology in the German education policy. The collaboration between Biology teachers, evolutionary biologists, philosophers, and educators resulted in teaching material for lessons about evolution in primary schools (cp. Graf/Schmidt-Salomon 2016). From a current perspective, a possible expansion of the material to an inclusive education setting is explained, which allows a capacity to deal with heterogeneous target groups. This approach is based on the differentiation matrices by Sasse and Schulzeck (2013). (DIPF/Orig.
Lespedeza virginica Britton.
https://thekeep.eiu.edu/herbarium_specimens_byname/6026/thumbnail.jp