39 research outputs found

    The application of Synchrotron X-ray micro-tomography in insect morphology

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    Die herkömmliche Methode der Untersuchung anatomischer Verhältnisse bei Insekten ist die manuelle Präparation und das Erstellen von Schnittserien eines eingebetteten Objektes in zwei, besser drei orthogonalen Raumrichtungen (frontal, axial und sagittal). Diese Schnitte werden dann spezifisch angefärbt und über Zeichnungen und / oder Fotographien ausgewertet. Mit speziellen zeichnerischen Verfahren oder mittels Graphikprogrammen können daraus 3D-Objekte „rekonstruiert“ werden. Eine neue vielversprechende Methode in der Insektenmorphologie ist die (phasenverstärkte) Synchrotron Mikro-Röntgentomographie. Ähnlich wie etwa bei den von Hörnschemeyer et al. (2002) genutzten Desktopgeräten wird hier mit relativ geringem Zeitaufwand der Vergleich kompletter „virtueller“ Schnittserien auch einer größeren Anzahl von Taxa, wie sie zum Beispiel für vergleichend-morphologische evolutionsbiologische Studien erforderlich sind, ermöglicht. Man erhält mittels der Tomographie-Datensätze die Möglichkeit, beliebige Schnittrichtungen am Computer zu bearbeiten und auszuwerten. Die Methode arbeitet zerstörungsfrei und ist somit auch für Museumsleihgaben oder seltene Einzelfunde geeignet.The (synchrotron-based) method of computer tomography is a non-invasive technique novel to insect morphology. It provides the researcher with the opportunity to investigate virtual serial sections through millimeter-sized objects of interest without destroying them. Here, we explain the principle of the technique and provide two illustrative examples. The first example relates to the muscles of the head and the structure of the inner head skeleton (tentorium) of Gyrophaena fasciata (Marsham) (Coleoptera, Staphylinidae: Aleocharinae). It is shown that SR-μCT is a useful technique to track muscles within the head and also to graphically represent the results. Moreover, it is demonstrated that the inner head skeleton elements can be three-dimensionally modeled and visualized. Our second example refers to the hind leg of Altica sp. (Coleoptera, Chrysomelidae: Alticini), in which details of the jumping mechanism could be further elucidated

    Reduction of radiation transmission through functionalization of textiles from man-made cellulosic fibers

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    Both ultraviolet (UV) and infrared (IR) light have negative impact on the human health. With this background it is the main aim of the current research to realize a textile material which is able to protect against both UV light and IR light. For this research, regenerated cellulosic fibers from the Lyocell process are used and modified. Main analytical investigations are done by photo-spectroscopy in arrangement of diffuse transmission for the spectral range from 220 nm to 1400 nm. Additionally, microscopic investigations are done by scanning electron microscopy (SEM). For material development, Lyocell fibers functionalized with TiO2 particles are first processed into yarns and then into knitted fabrics. Compared to non-functionalized textiles, the transmission is reduced in the UV range due to the absorption behavior of TiO2. Subsequent dyeing with anthraquinone or reactive dyes enhanced the UV protective effect. To reduce the transmission in the near IR range (NIR), non-functionalized Lyocell knitted fabrics are functionalized with various IR absorbers in different concen­trations. With increasing concentration, the transmission de­creased. However, a grey coloration of the textile is observed simultaneously, with increased concentration. This must be con­sidered in further processing steps. With these methods for function­alization, it is possible to produce textiles that offer increased protection against UV and IR radiation. These are promising materials for the production of clothing or work wear

    Fouling community composition on a pilot floating solar-energy installation in the coastal Dutch North Sea

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    The increasing need for renewable energy has led to the transition of renewable energy devices to the marine environment. Currently, mainly offshore wind farms have been completely developed and are operational in the North Sea. The solar energy sector is also rapidly evolving and floating photovoltaics are continuously created and deployed. In this study, we investigated the colonisation patterns and community changes with time of fouling fauna on the first floating photovoltaics in the coastal Dutch North Sea. Samples were collected by divers from the underwater side of 4 floaters, coated with different anti-fouling techniques (Intersleek, GreenPowerNano PPDura, Finsulate and Pato) at two different moments, shortly after the deployment of the floaters and approximately a year later. In total, 72 fouling taxa were identified on the floaters, from which ca. 11% are known to be non-indigenous species for the region. The anti-fouling coating Intersleek seemed to work the most efficiently against fouling colonisation, since the fouling community sampled from this floater contained the least taxa. However, the small number of samples collected from the different floaters did not allow for a direct comparison between the anti-fouling coatings. The communities evolved with time, with young communities accommodating a larger number of individuals and old communities having less individuals but higher biomass, indicating that the organisms become bigger in size and compete for the available space. Nevertheless, the communities had not reached a stable climax yet, while this process might take multiple years due to the dynamic environment in which floating photovoltaics are deployed. Monitoring the fouling communities occurring on floating photovoltaics in the North Sea for a long-term is necessary to understand the effects of these new man-made structures on the marine environment, especially since floating photovoltaics are moving to offshore locations and will be possibly co-located with offshore wind farms in the future

    Herausforderung Inklusion: Schule - Unterricht - Profession

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    Das Übereinkommen der Vereinten Nationen über die Rechte von Menschen mit Behinderungen sowie das dazu gehörende Fakultativprotokoll zum Übereinkommen der Vereinten Nationen über die Rechte von Menschen mit Behinderungen trat am 26.03.2009 ohne Einschränkung als innerstaatliches deutsches Recht in Kraft. Sich mit diesen vielschichtigen Themenkomplexen auseinanderzusetzen war das Ziel der Tagung „Herausforderung Inklusion: Schule – Unterricht – Profession“, die am 27. und 28. März 2014 an der Otto-Friedrich-Universität in Bamberg stattfand und sowohl betroffene Eltern, als auch Praktikerinnen und Praktiker und Wissenschaftlerinnen und Wissenschaftler zur Diskussion einlud. Der vorliegende Band geht auf diese Tagung zurück und möchte die vielfältigen Facetten der theoretischen, konzeptuellen und didaktisch-methodischen Zugänge im Kontext der derzeit geführten Debatten und Argumentationsmuster um ein inklusives Bildungswesen abbilden und neue Perspektiven für Forschung, Disziplin und Profession anregen. Demzufolge liegt der Fokus der Beiträge zum einen auf der Auseinandersetzung mit theoretischen Zugängen zur Inklusion sowie der Diskussion von nationalen und internationalen empirischen Erkenntnissen aus Studien der Inklusionsforschung, zum anderen auf der Präsentation von inklusiven Konzepten einer Schulentwicklung, (fach)didaktisch-methodischen Überlegungen und Modellprojekten aus der Praxis

    Guidelines for the use and interpretation of assays for monitoring autophagy (3rd edition)

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    In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. For example, a key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process versus those that measure fl ux through the autophagy pathway (i.e., the complete process including the amount and rate of cargo sequestered and degraded). In particular, a block in macroautophagy that results in autophagosome accumulation must be differentiated from stimuli that increase autophagic activity, defi ned as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (inmost higher eukaryotes and some protists such as Dictyostelium ) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the fi eld understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. It is worth emphasizing here that lysosomal digestion is a stage of autophagy and evaluating its competence is a crucial part of the evaluation of autophagic flux, or complete autophagy. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. Along these lines, because of the potential for pleiotropic effects due to blocking autophagy through genetic manipulation it is imperative to delete or knock down more than one autophagy-related gene. In addition, some individual Atg proteins, or groups of proteins, are involved in other cellular pathways so not all Atg proteins can be used as a specific marker for an autophagic process. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field

    An iterative approach to robust and integrated aircraft routing and crew scheduling

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    In airline scheduling a variety of planning and operational decision problems have to be solved. We consider the problems aircraft routing and crew pairing: aircraft and crew must be allocated to flights in a schedule in a minimal cost way. Although these problems are not independent, they are usually formulated as independent mathematical optimisation models and solved sequentially. This approach might lead to a suboptimal allocation of aircraft and crew, since a solution of one of the problems may restrict the set of feasible solutions of the problem solved later. Also, when minimal cost solutions are used in operations, a short delay of one flight can cause very severe disruptions of the schedule later in the day. We generate solutions that incur small costs and are also robust to typical stochastic variability in airline operations. We solve the two original problems iteratively. Starting from a minimal cost solution, we produce a series of solutions which are increasingly robust. Using data from domestic airline schedules we evaluate the benefits of the approach as well as the trade-off between cost and robustness. We extend our approach considering the aircraft routing problem together with two crew pairing problems, one for technical crew and one for flight attendants
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