4 Material und Umwelt
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- 2021 (5) (entfernen)
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- 3D printing (1)
- Anobium punctatum (1)
- DNA barcode (1)
- Drywood termite (1)
- Flügel (1)
- Gene expression (1)
- Insect biotechnology (1)
- Keratin (1)
- Korynetes caeruleus (1)
- Kulturelle Entomologie (1)
Organisationseinheit der BAM
- 4 Material und Umwelt (5)
- 4.1 Biologische Materialschädigung und Referenzorganismen (5)
- 4.0 Abteilungsleitung und andere (2)
- 5 Werkstofftechnik (1)
- 5.4 Multimateriale Fertigungsprozesse (1)
- 6 Materialchemie (1)
- 6.1 Oberflächen- und Dünnschichtanalyse (1)
- 8 Zerstörungsfreie Prüfung (1)
- 8.0 Abteilungsleitung und andere (1)
Viele Menschen erfreuen sich an Schmetterlingen. Besonders die farbfrohen Tagfalter lösen angenehme Gefühle aus. In der kulturellen Entomologie haben Schmetterlinge daher einen hohen Stellenwert, so auch in der schöngeistigen Literatur. Eine aktuelle stichprobenartige Untersuchung von 54 Büchern der deutschsprachigen Belletristik mit Insektenbezug im Titel oder auf dem Cover zeigte, dass sich zwei Drittel von ihnen des Schmetterlingnarrativs bedienten. Die folgende Analyse setzte das Ergebnis in einen historischen Bezug zur Verwendung von Insektenvorbildern in der Unterhaltungsliteratur und in Autorenbiografien. Die besondere Stellung der Schmetterlinge wird dabei geschichtlich als Relikt einer kulturellen Genese mit mythologisch-religiösen Wurzeln interpretiert. Im antiken Griechenland wurde die Bezeichnung Psyche mit bewusster Doppelbedeutung für Schmetterling und Seele verwendet. Im Hellenismus wurden die Seele und Seelenwesen wie z. B. die Daimons (Genien) oftmals mit Schmetterlingsflügeln dargestellt. Auch in den levantinischen Religionen wurden einzelne Gottheiten und Schutzgeister mit Flügeln nach Schmetterlingsart, jedoch aus Vogelfedern bestehend, abgebildet. Mit der Entstehung und Verbreitung der monotheistischen Lehren gingen viele dieser geflügelten Glaubenswesen dann in die Engelschöre über. Auch wenn die Flügel der Engel letztendlich wahrscheinlich von denen der Vögel abzuleiten sind, bleibt ein starker emotionaler Bezug zu den Schmetterlingen, der weit über den rein ästhetischen ausstrahlt.
Frass (fine powdery refuse or fragile perforated wood produced by the activity of boring insects) of larvae of the European house borer (EHB) and of drywood termites was tested as a natural and novel feedstock for 3D-printing of wood-based materials. Small particles produced by the drywood termite Incisitermes marginipennis and the EHB Hylotrupes bajulus during feeding in construction timber, were used. Frass is a powdery material of particularly consistent quality that is essentially biologically processed wood mixed with debris of wood and faeces. The filigree-like particles flow easily permitting the build-up of woodbased structures in a layer wise fashion using the Binder Jetting printing process. The Quality of powders produced by different insect species was compared along with the processing steps and properties of the printed parts. Drywood termite frass with a Hausner Ratio HR = 1.1 with ρBulk = 0.67 g/cm3 and ρTap = 0.74 g/cm3 was perfectly suited to deposition of uniformly packed layers in 3D printing. We suggest that a variety of naturally available feedstocks could be used in environmentally responsible approaches to scientific material sciences/additive manufacturing.
The clothes moth Tineola bisselliella is one of a few insects that can digest keratin, leading to the destruction of clothing, textiles and artwork. The mechanism of keratin digestion is not yet fully understood, partly reflecting the lack of publicly available genomic and transcriptomic data. Here we present a high-quality gut transcriptome of T. bisselliella generated from larvae reared on keratin-rich and keratin-free diets. The overall transcriptome consists of 428,221 contigs that were functionally annotated and screened for candidate enzymes involved in keratin utilization. As a mechanism for keratin digestion, we identified cysteine synthases, cystathionine β-synthases and cystathionine γ-lyases. These enzymes release hydrogen sulfite, which may reduce the disulfide bonds in keratin. The dataset also included 27 differentially expressed contigs with trypsin domains, among which 20 were associated with keratin feeding. Finally, we identified seven collagenases that were upregulated on the keratin-rich diet. In addition to this enzymatic repertoire potentially involved in breaking down keratin, our analysis of poly(A)-enriched and poly(A)-depleted transcripts suggested that T. bisselliella larvae possess an unstable intestinal microbiome that may nevertheless contribute to keratin digestion
Chemical modification of wood applying benzotriazolyl-activated carboxylic acids has proven to be a versatile method for the durable functionalization of its lignocellulosic biopolymers. Through this process, the material properties of Wood can be influenced and specifically optimized. To check the scope and limitations of this modification method, various benzamide derivatives with electron-withdrawing (EWG) or electron-donating (EDG) functional groups in different positions of the aromatic ring were synthesized and applied for covalent modification of Scots pine (Pinus sylvestris L.) sapwood in this study. The bonded amounts of substances (up to 2.20 mmol) were compared with the reactivity constants of the Hammett equation, revealing a significant correlation between the modification efficiency and the theoretical reactivity constants of the corresponding aromatic substitution pattern. The successful covalent attachment of the respective substituted benzamides was proven by attenuated total reflection infrared (ATR-IR) spectroscopy, while the stability of the newly formed ester bond was proven in a standardized leaching test.
Wood-destroying pests such as Anobium punctatum and Xestobium rufovillosum cause damage to art and cultural objects as well as to buildings. Monitoring population dynamics of pest species as well as of their naturally occurring counterparts are an essential part in the development of biological control measures as alternatives to conventional wood protection. Therefore, both the dispersal and homogeneity of pest and beneficial insect populations across multiple sites and buildings were investigated in the present study using DNA barcoding. Specifically, beetles of Anobium punctatum (de Geer 1774) (Coleoptera, Ptinidae), Xestobium rufovillosum (de Geer, 1974) (Coloeptera, Ptinidae), and Korynetes caeruleus (de Geer 1775) (Coleoptera, Cleridae) were collected from buildings at four different sites in Mecklenburg-Western Pomerania, North-Eastern Germany. DNA analysis was performed using mitochondrial cytochrome c oxidase subunit I (COI). For A. punctatum, low base pair variability was found in the gene segment studied (4-5 SNPs) within one building (Greven) and between four spatially separated sites. Conversely, in X. rufovillosum, the sequences from two sites studied were homogeneous within a site but differed between locations by nine base pair positions (SNPs). The main result of this study is that the pests A. punctatum and X. rufovillosum showed a higher variability in the investigated gene segment than the natural counterpart K. caeruleus.