252 research outputs found
A Survey of Teachers’ Media Literacy in Chinese Vocational Schools
Media in the context of education, especially new media like Web 2.0, has attracted the public’s attention for more than a decade now. Trendsetting research and publications have been carried out and published in this field and so it remains a popular topic nowadays. This paper focusses on the descriptions of media-pedagogic activities and attitudes of Chinese teachers in vocational education schools. Therefore, the research methodology and main findings of the empirical study, which involved questionnaires at Chinese vocational schools, will be presented
Wissensgemeinschaften: Digitale Medien – Öffnung und Offenheit in Forschung und Lehre
Die Herausgeber, die zugleich Ausrichter der 16. Europäischen Jahrestagung der Gesellschaft für Medien in der Wissenschaft „GMW 2011“ sind, freuen sich, den E-Learning-Akteuren aus dem deutschsprachigen Raum und den Nachbarländern im 20. Jahr des Bestehens der GMW als Fortsetzung eines bisher sehr fruchtbaren Dialoges diesen Sammelband, der in der Reihe „Medien in der Wissenschaft“ beim Waxmann Verlag erscheint, vorzulegen. Unter dem Motto „WissensGemeinschaften in Forschung und Lehre“ liegt ein besonderer Schwerpunkt auf der Verzahnung von E-Learning-Angeboten in der Ausbildung an der Universität mit solchen für allgemein- und berufsbildende Schulen. Dabei soll auch der didaktische Aspekt Beachtung finden. (... aus dem Vorwort
Photocycle of a cyanobacteriochrome: a charge defect on ring C impairs conjugation in chromophore
A large number of novel phytochromes named cyanobacteriochromes (CBCRs) have been recently identified. CBCRs appear to be attractive for further in-depth studies as paradigms for phytochromes because of their related photochemistry, but simpler domain architecture. Elucidating the mechanisms of spectral tuning for the bilin chromophore down to the molecular/atomic level is a prerequisite to design fine-tuned photoswitches for optogenetics. Several explanations for the blue shift during photoproduct formation associated with the red/green CBCRs represented by Slr1393g3 have been developed. There are, however, only sparse mechanistic data concerning the factors controlling stepwise absorbance changes along the reaction pathways from the dark state to the photoproduct and vice versa in this subfamily. Conventional cryotrapping of photocycle intermediates of phytochromes has proven experimentally intractable for solid-state NMR spectroscopy within the probe. Here, we have developed a simple method to circumvent this hindrance by incorporating proteins into trehalose glasses which allows four photocycle intermediates of Slr1393g3 to be isolated for NMR use. In addition to identifying the chemical shifts and chemical shift anisotropy principal values of selective chromophore carbons in various photocycle states, we generated QM/MM models of the dark state and photoproduct as well as of the primary intermediate of the backward-reaction. We find the motion of all three methine bridges in both reaction directions but in different orders. These molecular events channel light excitation to drive distinguishable transformation processes. Our work also suggests that polaronic self-trapping of a conjugation defect by displacement of the counterion during the photocycle would play a role in tuning the spectral properties of both the dark state and photoproduct
Patterns of biomedical science production in a sub-Saharan research center
<p>Abstract</p> <p>Background</p> <p>Research activities in sub-Saharan Africa may be limited to delegated tasks due to the strong control from Western collaborators, which could lead to scientific production of little value in terms of its impact on social and economic innovation in less developed areas. However, the current contexts of international biomedical research including the development of public-private partnerships and research institutions in Africa suggest that scientific activities are growing in sub-Saharan Africa. This study aims to describe the patterns of clinical research activities at a sub-Saharan biomedical research center.</p> <p>Methods</p> <p>In-depth interviews were conducted with a core group of researchers at the Medical Research Unit of the Albert Schweitzer Hospital from June 2009 to February 2010 in Lambaréné, Gabon. Scientific activities running at the MRU as well as the implementation of ethical and regulatory standards were covered by the interview sessions.</p> <p>Results</p> <p>The framework of clinical research includes transnational studies and research initiated locally. In transnational collaborations, a sub-Saharan research institution may be limited to producing confirmatory and late-stage data with little impact on economic and social innovation. However, ethical and regulatory guidelines are being implemented taking into consideration the local contexts. Similarly, the scientific content of studies designed by researchers at the MRU, if local needs are taken into account, may potentially contribute to a scientific production with long-term value on social and economic innovation in sub-Saharan Africa.</p> <p>Conclusion</p> <p>Further research questions and methods in social sciences should comprehensively address the construction of scientific content with the social, economic and cultural contexts surrounding research activities.</p
Alltagsbewußtsein und Milieustruktur der westdeutschen Studierenden in den 80er und 90er Jahren: Studierende im Spiegel der Milieulandschaft Deutschlands
"Ziel der Studie ist es, mit einem lebensstilanalytischen Ansatz Aussagen über die Struktur und Beschaffenheit der Studierenden als soziale Gruppe insgesamt und vor allem in ihrer lebensweltlichen Differenziertheit und Entwicklung zu machen. Die Ebene der sozialstatistischen Daten zu Einkommen, Studienzeiten, Fachwahl oder Berufsvorstellungen wird dabei bewußt verlassen. Die Analyse hat vielmehr den Rahmen, den die Werte und Lebensweisen der großen sozialen Milieus unserer Gesellschaft vorgeben, und die sich - wie angenommen wird - auch in den Hochschulen wiederfinden, zur Grundlage. Was 'Studieren' und 'Studium' jeweils bedeutet, ist auch Ergebnis historischer sozialer Prozesse und Konflikte, die in Form von Milieukonstellationen in einer diachronen Perspektive, in zwei Momentaufnahmen mit einem Abstand von zehn Jahren, nachskizziert werden soll. Das Studierendenmilieu wird dabei als komplexe, heterogene und oft disparate Einheit verstanden, dessen einheitsstiftende Momente - die als legitim anerkannten Werte, Lebensweisen und Studienziele - permanent umkämpft sind. Es gibt also Milieufraktionen, die nicht als gut abgegrenzte oder auch einander überschneidende Typen, als bloß analytische Einheiten zu verstehen sind, sondern als soziale Gesellschaftsgruppen, denen sich die Studierenden nicht nur im Verlauf ihres Studiums, sondern immerwährend und mit aller Leidenschaft zuordnen, zuzuordnen versuchen oder von denen sie sich abgrenzen bzw. ausgegrenzt werden. Unter dieser zunächst makrosoziologischen milieuanalytischen Perspektive geraten die sozialen, d.h. subjektiven und objektiven Strukturierungen, die internen Ausgrenzungen und Fraktionierungen im Studierendenmilieu ins Zentrum der Betrachtung. Unterhalb der Ebene der Großmilieus bedarf ein lebensstilanalytischer Ansatz in der Studierendenforschung aber auch einer mikrosoziologischen Auseinandersetzung mit den individuellen Biografien, Lebensweisen und Lebensstilen, um so den Verknüpfungen zu den gelebten 'Studienstilen' auf die Spur zu kommen. Das Studierendenmilieu soll hier deshalb als ein transitorisches Feld der Möglichkeiten verstanden werden. Die Studierenden kommen mit Dispositionen und Aspirationen, ihrem Habitus und den Kapitalressourcen ihrer Herkunftsmilieus in dieses Kräftefeld der Hochschulen, das auf sie mit Angeboten und Zurückweisungen einwirkt. Die Kräfte sind von den Fachkulturen am Standort repräsentiert und in ihrer jeweiligen Profession verkörpert. Gliederung: 1. Einleitung; 2. Die Datenbasis der Untersuchung; 3. Wertorientierungen und Alltagsbewußtsein westdeutscher Studierender Mitte der 90er Jahre; 4. Zentrale Dimensionen des Alltagsbewußtseins; 5. Das Konzept der Sinus Lebensweltforschung; 6. Struktur und Entwicklung der westdeutschen Milieulandschaft von 1986 bis 1996; 7. Zur Milieustruktur der westdeutschen Studierenden 1986 und 1996; 8. Anhang." (Textauszug
Chip technology for fast serological determination of Salmonella serovars
The nucleotide sequence encoding the Salmonella plasmid virulence factor D (SpvD) was determined in 17 Salmonella strains that were different in O and H antigen patterns, animal host and geographical origin, and year of isolation. Nucleotide sequence comparison revealed the existence of at least nine spvD alleles resulting in 8 SpvD protein variants although the nucleotide sequences were highly similar (identity 98.8- 100 %)
Light- and pH-dependent structural changes in cyanobacteriochrome AnPixJg2
Cyanobacteriochromes (CBCRs) are phytochrome-related photosensory proteins that play an essential role in regulating phototaxis, chromatic acclimation, and cell aggregation in cyanobacteria. Here, we apply solid-state NMR spectroscopy to the red/green GAF2 domain of the CBCR AnPixJ assembled in vitro with a uniformly 13C- and 15N-labeled bilin chromophore, tracking changes in electronic structure, geometry, and structural heterogeneity of the chromophore as well as intimate contacts between the chromophore and protein residues in the photocycle. Our data confirm that the bilin ring D is strongly twisted with respect to the B–C plane in both dark and photoproduct states. We also identify a greater structural heterogeneity of the bilin chromophore in the photoproduct than in the dark state. In addition, the binding pocket is more hydrated in the photoproduct. Observation of interfacial 1H contacts of the photoproduct chromophore, together with quantum mechanics/molecular mechanics (QM/MM)-based structural models for this photoproduct, clearly suggests the presence of a biprotonated (cationic) imidazolium side-chain for a conserved histidine residue (322) at a distance of ~2.7 Å, generalizing the recent theoretical findings that explicitly link the structural heterogeneity of the dark-state chromophore to the protonation of this specific residue. Moreover, we examine pH effects on this in vitro assembled holoprotein, showing a substantially altered electronic structure and protonation of the photoproduct chromophore even with a small pH drop from 7.8 to 7.2. Our studies provide further information regarding the light- and pH-induced changes of the chromophore and the rearrangements of the hydrogen-bonding and electrostatic interaction network around it. Possible correlations between structural heterogeneity of the chromophore, protonation of the histidine residue nearby, and hydration of the pocket in both photostates are discussed
Intercellular communication inArabidopsis thalianapollen discovered viaAHG3transcript movement from the vegetative cell to sperm
An Arabidopsis pollen grain (male gametophyte) consists of three cells: the vegetative cell, which forms the pollen tube, and two sperm cells enclosed within the vegetative cell. It is still unclear if there is intercellular communication between the vegetative cell and the sperm cells. Here we show that ABA-hypersensitive germination3 (AHG3), encoding a protein phosphatase, is specifically transcribed in the vegetative cell but predominantly translated in sperm cells. We used a series of deletion constructs and promoter exchanges to document transport of AHG3 transcripts from the vegetative cell to sperm and showed that their transport requires sequences in both the 5' UTR and the coding region. Thus, in addition its known role in transporting sperm during pollen tube growth, the vegetative cell also contributes transcripts to the sperm cells.US Department of Agriculture-Agricultural Research Service Current Research Information System Grant: (5335–21000–030–00D), European Research Council Starting Independent Researcher grant
An Enigmatic Pointlike Feature within the HD 169142 Transitional Disk
We report the detection of a faint pointlike feature possibly related to
ongoing planet-formation in the disk of the transition disk star HD 169142. The
pointlike feature has a mag(L)6.4, at a separation of 0.11"
and PA0. Given its lack of an H or K counterpart despite
its relative brightness, this candidate cannot be explained by purely
photospheric emission and must be a disk feature heated by an as yet unknown
source. Its extremely red colors make it highly unlikely to be a background
object, but future multi-wavelength followup is necessary for confirmation and
characterization of this feature.Comment: Accepted to ApJ Letters, see also Reggiani et al. 201
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