121 research outputs found
Childhood Memories of Valdemar Lenschow, Morten Jørgensen, Rose Hallmann and Lasse Holmelund
No full text<p>This is a student project, not meant for proper publication, but for testing and learning the techniques and uses of data management.</p><p> </p><p>The following dataset is based on childhood artifacts or memories. The Data collected was made by four students at the Aarhus Universitet in the year 2023.The four authors have chosen widely different objects, such as childhood toys, artifacts with personal meaning, family photos associated with childhood memories etc. <br>The idea is the data can be expanded by other users, who in turn have to fill out a data overview document, in which they follow already existing categories, as well as filling out metadata and keywords, to make the data usable by researchers. <br>The significance of each chosen data is individual for each author, but with both context and significance for their respective childhood.<br><br>As for the naming of the files we decided to start with the person the item belonged to, which we found relevant as the digital collection only have items belonging to the four of us. Then a number for the item, as to make the digital sorting easier to handle and sort ind. Then a category description such as manga, video, picture to further ease categorizing, sometimes more to further ease categorizing. Finally, a name, number or description for the specific item, or page, again sometimes more to ease access.</p>
Molecular and cellular dynamics of early embryonic cell divisions in Volvox carteri
No full textvon der Heyde EL, Hallmann A. Molecular and cellular dynamics of early embryonic cell divisions in Volvox carteri. Plant Cell. 2022;34(4):1326–1353.Cell division is fundamental to all organisms, and the green alga used here exhibits both key animal and plant functions. Specifically, we analyzed the molecular and cellular dynamics of early embryonic divisions of the multicellular green alga Volvox carteri (Chlamydomonadales). Relevant proteins related to mitosis and cytokinesis were identified in silico, the corresponding genes were cloned, fused to yfp, and stably expressed in Volvox, and the tagged proteins were studied by live-cell imaging. We reveal rearrangements of the microtubule cytoskeleton during centrosome separation, spindle formation, establishment of the phycoplast and generation of previously unknown structures. The centrosomes participate in initiation of spindle formation and determination of spindle orientation. Although the nuclear envelope does not break down during early mitosis, intermixing of cytoplasm and nucleoplasm results in loss of nuclear identity. Finally, we present a model for mitosis in Volvox. Our study reveals enormous dynamics, clarifies spatio-temporal relationships of subcellular structures and provides insight into the evolution of cell division. © The Author(s) 2022. Published by Oxford University Press on behalf of American Society of Plant Biologists
A New Eulerian Model for Turbulent Evaporating Sprays in Recirculating Flows
No full textA new Eulerian model for the computation of turbulent evaporating sprays in recirculating flows is derived. It comprises droplet heating and evaporation processes by solving separate transport equations for the droplet's temperature and diameter. Full coupling of the droplet and the gaseous phase is achieved by the exchange of source terms due to momentum, heat and mass transfer. The partial differential equations describing the droplet's transport and evaporation in the new method can be solved using the same numerical procedure as for the gas phase equations. The validity of the model is established by comparison with a well known Lagrangian approach and with experimental data. For this purpose calculations of a recirculating droplet charged air flow within a model combustor are presented.Aerospace Engineerin
First report of barley yellow dwarf virus PAS in maize in Türkiye
No full text[Abstract Not Available]Julius Kuhn Institute, Leibniz Institute DSMZ; European Virus Archive Global (EVAg) Project; Tekirdag Namimath;k Kemal University; Scientific Research Projects Coordination Unit (NKU-BAP)This work was supported by the Julius Kuhn Institute, Leibniz Institute DSMZ, Germany, and the European Virus Archive Global (EVAg) Project. Additional funding for the work came from the Tekirdag Nam & imath;k Kemal University, The Scientific Research Projects Coordination Unit (NKU-BAP). The author would like to thank Prof. Dr. Frank Ordon and Dr. Johannes Hallmann for their support of the research
Clay, stones, shards ...
No full textIn der vorliegenden Arbeit wird die Entwicklungsgeschichte der in historischen Gärten in Deutschland angewandten baulich-konstruktiven Methoden des Wasser- und Wegebaus von 1800 und 1930 untersucht. Diese Analyse stellt einerseits einen Beitrag zur Fachgeschichte des Garten- und Landschaftsbaus dar, andererseits ist sie die erste, umfassende Untersuchung zur Bauforschung in der Gartendenkmalpflege, einem bisher wenig erforschten Spezialgebiet der Denkmalpflege. Gegenstand der Untersuchung sind historische Wasser- und Wegebauweisen, die häufig in Gartenanlagen vorkommen. Als Erdbauwerke repräsentieren sie die Entwicklung der Fachdisziplin des Garten- und Landschaftsbaus. Die Untersuchung erfolgt durch eine vergleichende Betrachtung der im entsprechenden Zeitraum veröffentlichten Fachliteratur. Um den allgemeinen Stand der Technik zu zeigen, werden ergänzend einschlägige Werke aus den Ende des 18. Jahrhunderts aufkommenden Ingenieurwissenschaften des Teich- und Flußbaus sowie des Straßen- und Wegebaus herangezogen. Neben der chronologischen Entwicklung einzelner Bauweisen des Wasser- und Wegebaus konnte durch diese Betrachtung außerdem eine zunehmende Identifikation der Gartenkünstler mit den baulich-konstruktiven Aspekten ihrer Fachdisziplin nachvollzogen werden, die sich Anfang des 20. Jahrhunderts in der neuen Berufsbezeichnung "Gartenarchitekt" niederschlug. Da von den Beschreibungen in der Fachliteratur nicht deduktiv auf die praktische Anwendung bestimmter Bauweisen geschlossen werden kann, werden im zweiten Teil der Untersuchung Teiche und wassergebundene Wege in historischen Gartenanlagen anhand von Projektbeispielen aus der Gartendenkmalpflege untersucht. Die Auswertung der Beispiele erfolgt auf der Basis der allgemeinen Grundsätze der Denkmalpflege. Ein Teil der Angaben in den Lehrbüchern konnte durch die untersuchten Beispiele bestätigt werden, bei anderen Beispielen ergaben sich jedoch Widersprüche. Teilweise blieben Fragen offen oder es ergaben sich weiterführende Erkenntnisse. Deutlich wurde die dringende Notwendigkeit einer bisher noch nicht erfolgten systematischen, anlagenübergreifenden Auswertung dieser Daten. Weiterhin ist festzustellen, daß für die Befunderhebung und Dokumentation von historischen Wasseranlagen und Wegen zur Zeit keine einheitliche, wissenschaftlich fundierte Methode angewendet wird. Außerdem wird bei der Instandhaltung und Sanierung historischer Wege- und Wasseranlagen der denkmalpflegerische Grundsatz des behutsamen Umgangs mit der Originalsubstanz nicht immer beachtet. Diese Ergebnisse zeigen die dringende Notwendigkeit einer Diskussion über eine Vereinheitlichung dieser Methoden innerhalb der Gartendenkmalpflege. Im letzten Teil der Untersuchung wird deshalb eine wissenschaftliche Methode der Befunderhebung und Dokumentation sowie der Instandhaltung und Sanierung unter der Prämisse einer möglichst weitgehenden Erhaltung der Originalsubstanz vorgelegt
The perspective for proactive Cluster policies in Bavaria against the background of positioning the SME (small and medium sized enterprises) sector
No full textIm Rahmen der Struktur- und Regionalpolitik werden zunehmend tragfähige Netzwerkkonzepte zur wirtschaftlichen Stärkung der Regionen diskutiert. Hierbei erfolgt ein Paradigmenwechsel weg von der früheren kostenbezogenen Subventionsmentalität zu einer angebotsorientierten Förderung der Wettbewerbsstärken über sogenannte "Cluster". Vor dem Hintergrund der Einbindung des Clusterkonzepts in die Mittelstandspolitik der Bayerischen Staatsregierung wird eine quantitative und qualitative Abgrenzung des Begriffs "Mittelstand" vorgenommen. Anschließend werden in Anlehnung an die Neue Ökonomische Geographie unter Würdigung der regional- und innovationspolitischen Ansätze in der wissenschaftlichen Literatur die zentralen Zielsetzungen von Netzwerkkonzepten und Clusterinitiativen dargestellt. Hierbei werden anstelle eines "Best Practice"-Musters eine Reihe von Mustern guter Praxis vorgestellt. Die Zentrale These, wonach Cluster nicht ad hoc darstellbar sind, sondern auf einen Stärkenfundus der Region zurückzugreifen ist, wird ausdrücklich bestätigt. Die bisherige Clusterpolitik des Freistaats Bayern wird erläutert und kritisch geprüft. Zur besseren Positionierung des Mittelstands wird die engere Verzahnung zwischen den Finanzmärkten und den Clusterinitiativen gefordert.There has been a shift in regional policy away from the mentality of cost-based subsidies towards a supply-side microeconomic approach of raising the potential in innovation and competitiveness of regions through "Clusters". As the State of Bavaria has declared cluster policy one of the key elements to promote SMEs, a clearer definition of that enterprise category underlines the importance ot the sector for the Bavarian economy. Along the lines of the New Economic Geography, network and cluster concepts are discussed against the background of promoting innovation and competition. Rather than concluding on ways of "Best Practice" , a number of examples of good practice are brought forward to emphasize the crucial elements of clusters. By drawing on a region's existing strengths, cluster promotion will be successful. Cluster initiatives will not succeed in creating clusters ab initio. The past and current cluster policies of the Sate of Bavaria and their implications for SMEs are discussed. As a supporting measure, the author advocates a stronger link between the financial markets and the cluster initiatives
Nematode dynamics under minimum tillage
No full textAgriculture has transformed over the past centuries dramatically to become highly dependent on non-renewable fossil fuels, synthetic fertilizers and plant protection agents. This often occurs at the cost of soil degradation and soil food web disturbance. Future agriculture must not only be productive but also provide ecosystem services such as carbon sequestration, pest and disease suppression, nutrient cycling and water storage to become sustainable in the long-term. Sustainability is especially fostered by reduced tillage and the presence of a permanent layer of plant residues. Under such conditions, soil compaction is reduced, soil structure improved, water infiltration enhanced, soil organic content increased and microbial activity stimulated. However, continuous soil cover, especially associated with permanent growth of plants, might also enhance plant-parasitic nematode densities due to permanent food supply. The effect of minimum tillage on nematode dynamics was studied within the EU-funded project “Optimizing subsidiary crop applications in rotations”. The rotation consisted of clover-grass, winter wheat, cover crop, and potato. The following treatments were studied: Plough versus minimum tillage, white clover versus subterranean clover as undersown crops in winter wheat, vetch versus a 1:4 mix of fodder radish and black oats as cover crop following winter wheat, and with and without 5t DM ha-1 compost application. Initially, the field was infested with Helicotylenchus, Meloidogyne, Paratylenchus, Pratylenchus and Tylenchorhynchus. Pratylenchus and Helicotylenchus increased under wheat and Meloidogyne was supported by white clover and subterranean clover as undersown crops. Population densities of all nematode taxa declined during the following catch crop and potato. There was no difference in nematode population dynamics between plough versus minimum tillage, nor between compost versus no compost. Results will be discussed considering the recent literature
Influence of an Angular Hatching Exposure Strategy on the Surface Roughness During Picosecond Laser Ablation of Hard Materials
No full textAbstractInnovative chip breakers for cutting tools made of very hard materials require laser ablation and demand a high quality regarding the manufactured surface. When processing materials such as polycrystalline cubic boron-nitride or tungsten carbide the surface roughness by laser ablation reaches Sa = 1,0-2,9 μm compared to Sa = 0,42 μm achieved by grinding. Therefore in the presented research the influence of the hatching exposure strategy on surface roughness during picosecond laser ablation of tungsten carbide is examined. The areal, layerwise ablation process is separated into its elements which are represented by intersection zones between single and multiple laser vectors. Thus two mechanisms of roughness formation are identified and described by model functions. Further the mechanisms are transferred to areal ablation in which surface roughness decreases due to improved hatching angles compared to a commonly used one of φ= 0°/90°. With this approach the roughness is reduced by approximately factor 2,0-3,5 to Sa = 0,82 μm. In conclusion guidelines are derived which present favorable settings for high quality laser ablation processes
Polyphenols vs. Caffeine in Coffee from Franchise Coffee Shops: Which Serving of Coffee Provides the Optimal Amount of This Compounds to the Body
No full textThe scientific literature indicates that there is a limited number of data on the content of bioactive components in coffees consumed “on the go”. Therefore, this study examined the polyphenol and caffeine content of different types of coffee from franchise coffee shops, and the caffeine/total polyphenol ratio. The five most popular types of coffee purchased in six franchise coffee shops in Warsaw were analysed. A total of 120 coffee samples were tested. A significant positive (r = 0.7407, p < 0.001) correlation was found between the total polyphenol and caffeine content in all coffee types tested. Per unit volume, espresso coffee had the highest significant (p < 0.005) average total polyphenol and caffeine contents (232.9 ± 63.9 mg/100 mL and 198.6 ± 68.3 mg/100 mL, respectively). After taking into account the coffee’s serving size, a serving of Americano provided significantly (p < 0.05) the most total polyphenol (average 223.5 ± 81.5 mg), while the highest caffeine content was provided by a serving of ice latte/latte frappe (average 136 ± 57.0 mg). The most favourable ratio of caffeine to total polyphenols (0.56) was found in a serving of Americano coffee; therefore, it seems that this coffee can be considered optimal in terms of the content of both compounds. These findings demonstrate that the polyphenol and caffeine contents of coffees offered in franchise coffee shops are closely related to the serving size
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