Kinder schreiben auf einer Internetplattform : Resultate aus der Interventionsstudie myMoment2.0

myMoment ist eine Internetplattform, auf der Grundschulkinder in bestimmten Grenzen frei ihre eigenen Texte veröffentlichen können. In einer Interventionsstudie wurde verglichen, wie sich Klassen, die auf myMoment arbeiten, in der Schreibleistungsentwicklung von Klassen unterscheiden, die nicht auf myMoment arbeiten. Die Lehrpersonen beider Gruppen wurden vom selben Team schreibdidaktisch weitergebildet. Überprüft wurde die Leistungsentwicklung im Verfassen von instruktiven und narrativen Texten sowie im Überarbeiten. Die Resultate zeigen, dass myMoment-Klassen sich hauptsächlich in der Entwicklung narrativer Schreibfähigkeiten deutlich besser entwickeln als die anderen Klassen. Besonders markant sind die Effekte bei Elementen der Textoberfläche, die als Resultate von literalen Prozeduren gedeutet werden können. Es scheint, dass sich das Wissen um literale Prozeduren teilweise über das Lesen von myMoment-Texten aufbaut

Sources and distribution of trace species in Alpine precipitation inferred from two 60-year ice core paleorecords

International audienceThe Alps represent the largest barrier to meridional air flow in Europe, strongly influencing the weather and hence the distribution of atmospheric trace components. Here for the first time, chemical records from two ice cores retrieved from glaciers located in the northern and southern Swiss Alps were compared in conjunction with an analysis of "weather type", in order to assess geographical and seasonal trends in the deposition of trace species and to identify source regions and transport patterns. Using a correlation analysis, investigated trace species (NH4+, NO3?, SO42?, Ca2+, Mg2+, Na+, K+, and Cl? were grouped into classes of different origin (anthropogenic, sea salt, or Saharan dust). Over the last 60 years, precipitation chemistry at both sites was dominated by NH4+, NO4?, and SO42?, all of anthropogenic origin and deposited mainly in summer by way of convective precipitation. The similarity of the SO42? profiles with historical records of SO4 emissions from France and Italy indicated these two countries as key source areas for the anthropogenic species. In contrast, sea salt and Saharan dust showed major differences in transport pattern and deposition across the Alps. Currently, the sea-salt constituents Na+, K+, and Cl? are transported to the northern site during advective westerly-wind situations, independent of Saharan dust events. At the southern site, sea salt and Saharan dust are deposited simultaneously, indicating a coupled transport active mainly in summer during south-westerly wind situations

Analysis of C. elegans intestinal gene expression and polyadenylation by fluorescence-activated nuclei sorting and 3′-end-seq

Despite the many advantages of Caenorhabditis elegans, biochemical approaches to study tissue-specific gene expression in post-embryonic stages are challenging. Here, we report a novel experimental approach for efficient determination of tissue-specific transcriptomes involving the rapid release and purification of nuclei from major tissues of post-embryonic animals by fluorescence-activated nuclei sorting (FANS), followed by deep sequencing of linearly amplified 3′-end regions of transcripts (3′-end-seq). We employed these approaches to compile the transcriptome of the developed C. elegans intestine and used this to analyse tissue-specific cleavage and polyadenylation. In agreement with intestinal-specific gene expression, highly expressed genes have enriched GATA-elements in their promoter regions and their functional properties are associated with processes that are characteristic for the intestine. We systematically mapped pre-mRNA cleavage and polyadenylation sites, or polyA sites, including more than 3000 sites that have previously not been identified. The detailed analysis of the 3′-ends of the nuclear mRNA revealed widespread alternative polyA site use (APA) in intestinally expressed genes. Importantly, we found that intestinal polyA sites that undergo APA tend to have U-rich and/or A-rich upstream auxiliary elements that may contribute to the regulation of 3′-end formation in the intestin

Development of Random Vibration Profiles for Test Deployers to Simulate the Dynamic Environment in the Poly-Picosatellite Orbital Deployer

TestPODs and P-PODs have different structures with different resonant frequencies. This causes a change in the frequency response for CubeSats integrated into TestPODs compared to P-PODs. Adjusted random vibration profiles were developed for TestPODs to simulate the dynamic environment of the P-POD so CubeSats would have a consistent response in both deployers. Testing has shown that, with proper characterization of TestPODs and P-PODs, adjusted profiles can be used for TestPODs to simulate the P-POD dynamic environment

A splicing-dependent transcriptional checkpoint associated with prespliceosome formation

There is good evidence for functional interactions between splicing and transcription in eukaryotes, but how and why these processes are coupled remain unknown. Prp5 protein (Prp5p) is an RNA-stimulated adenosine triphosphatase (ATPase) required for prespliceosome formation in yeast. We demonstrate through in vivo RNA labeling that, in addition to a splicing defect, the prp5-1 mutation causes a defect in the transcription of intron-containing genes. We present chromatin immunoprecipitation evidence for a transcriptional elongation defect in which RNA polymerase that is phosphorylated at Ser5 of the largest subunit’s heptad repeat accumulates over introns and that this defect requires Cus2 protein. A similar accumulation of polymerase was observed when prespliceosome formation was blocked by a mutation in U2 snRNA. These results indicate the existence of a transcriptional elongation checkpoint that is associated with prespliceosome formation during cotranscriptional spliceosome assembly. We propose a role for Cus2p as a potential checkpoint factor in transcription

From the workshop of Touareg silversmith Hamid Kumama in Agadez (Niger)

The essay documents and comments on the production of an "Iférouane cross" (silver pendant) using the lost wax process ("cire perdu"). The focus is on the Touareg silversmith Hamid Kumama working in his simple workshop in Agadez in 1973. The original workshop equipment, the simple tools, the traditional typical Touareg jewellery can hardly be found in the Sahel region today – machines and modern trends and designs have partly made the old techniques disappear

Analysis and Mitigation of the CubeSat Dynamic Environment

A vibration model was developed for CubeSats inside the Poly-Picosatellite Orbital Deployer (P-POD). CubeSats are fixed in the Z axis of deployers, and therefore resonate with deployer peaks. CubeSats generally start fixed in the X and Y axes, and then settle into an isolated position. CubeSats do not resonate with deployers after settling into an isolated position. Experimental data shows that the P-POD amplifies vibration loads when CubeSats are fixed in the deployer, and vibration loads are reduced when the CubeSats settle into an isolated position. A concept for a future deployer was proposed that isolates CubeSats from the deployer at the rail interface using viscoelastic foam sandwiched in the deployer rails. By creating an isolator frequency far below the deployer resonant frequency, CubeSats loads are not amplified at the deployer’s resonant peak. Feasibility tests show that CubeSat vibration loads can be reduced to 50% of the vibration input in certain cases. Testing also shows that it is much easier to define vibration loads for isolated CubeSats than CubeSats in the current P-POD

Aus der Werkstatt des Touareg-Silberschmiedes Hamid Kumama in Agadez (Niger)

Der Aufsatz dokumentiert und kommentiert die Herstellung eines «Iférouane-Kreuzes» (Silber-Anhänger) im Wachsausschmelzverfahren («cire perdu»). Im Zentrum steht der Touareg-Silberschmied Hamid Kumama, der 1973 in seiner einfachen Werkstatt in Agadez arbeitet. Die ursprüngliche Werkstatteinrichtung, die einfachen Werkzeuge, die traditionellen typischen Touareg-Schmuckstücke sind heute kaum mehr im Sahelgebiet anzutreffen – Maschinen und moderne Trends und Designs haben die alten Techniken teilweise zum Verschwinden gebracht

Quantification of topographic venting of boundary layer air to the free troposphere

International audienceNet vertical air mass export by thermally driven flows from the atmospheric boundary layer (ABL) to the free troposphere (FT) above deep Alpine valleys was investigated. The vertical export of pollutants above mountainous terrain is presently poorly represented in global chemistry transport models (GCTMs) and needs to be quantified. Air mass budgets were calculated using aircraft observations obtained in deep Alpine valleys. The results show that on average 3 times the valley air mass is exported vertically per day under fair weather conditions. During daytime the type of valleys investigated in this study can act as an efficient "air pump" that transports pollutants upward. The slope wind system within the valley plays an important role in redistributing pollutants. Nitrogen oxide emissions in mountainous regions are efficiently injected into the FT. This could enhance their ozone (O3) production efficiency and thus influences tropospheric pollution budgets. Once lifted to the FT above the Alps pollutants are transported horizontally by the synoptic flow and are subject to European pollution export. Forward trajectory studies show that under fair weather conditions two major pathways for air masses above the Alps dominate. Air masses moving north are mixed throughout the whole tropospheric column and further transported eastward towards Asia. Air masses moving south descend within the subtropical high pressure system above the Mediterranean

Alternative polyadenylation: less than meets the eye?

With the advances in deep-sequencing techniques over the last decade, the study of alternative cleavage and polyadenylation (APA) has shifted from individual gene to whole transcriptome analysis. Findings from such global studies have elevated APA to its currently accepted status as a major player in the regulation of eukaryotic gene expression. Although ~70% of human genes have been shown to contain multiple cleavage and polyadenylation sites, the extent of the consequences of APA and its role in regulating physiological processes are still largely unknown. The present review aims to summarize the experimental evidence that supports a physiological role of APA and highlights some of the shortcomings that need addressing to substantiate the widely proposed claim that APA is a key player in global gene regulation