The oriented and patterned growth of fluorescent metal–organic frameworks onto functionalized surfaces

A metal–organic framework (MOF) material, [Zn2(adc)2(dabco)] (adc = anthracene-9,10-dicarboxylate, dabco = 1,4-diazabicyclo[2.2.2]­octane), the fluorescence of which depends on the loading of its nanopores, was synthesized in two forms: as free-flowing nanocrystals with different shapes and as surface-attached MOFs (SURMOFs). For the latter, we used self-assembled monolayers (SAMs) bearing functional groups, such as carboxylate and pyridyl groups, capable of coordinating to the constituents of the MOF. It could be demonstrated that this directed coordination also orients the nanocrystals deposited at the surface. Using two different patterning methods, i.e., microcontact printing and electron-beam lithography, the lateral distribution of the functional groups could be determined in such a way that the highly localized deposition of the SURMOF films became possible

Einfluss von Stoppelhobel als Alternative zum Grubber auf Beikrautentwicklung und Dinkelertrag

Der modifizierte Schälpflug oder "Stoppelhobel" schützt den Boden durch seine flach wendende Arbeitsweise, unterdrückt Beikräuter durch das ganzflächige Unterschneiden des Bodens, reduziert den Energieverbrauch und ermöglicht höhere Arbeitsgeschwindigkeiten. Im Jahr 2016/17 wurde auf einem Biobauernhof im Waldviertel im nördlichen Niederösterreich ein Praxis-Feldversuch durchgeführt. Zwei Bodenbearbeitungsverfahren vor dem Dinkelanbau - Var. A: 3x Stoppelhobel, Var. B: 2x Grubber / 1x Stoppelhobel - wurden hinsichtlich Bodeneigenschaften, Beikrautdruck und Ertragsmerkmalen untersucht. Es wurden keine signifikanten Unterschiede zwischen dem Dinkel-Kornertrag (Var. A 17,2 dt TM ha-1 / Var. B 18,3 dt TM ha-1), den pflanzenverfügbaren Nährstoffen im Boden, Humusgehalt und der Beikrautdichte festgestellt. Die Versuchsergebnisse bestätigten den Stoppelhobel als Alternative zum Grubber, da die gleichen Ergebnisse mit einer geringeren Arbeitstiefe erzielt werden konnten

An optical-flow-based monitoring method for measuring translational motion in infrared-thermographic images of AFP processes

This paper presents a novel method for a precise localization of the automated-fiber-placement head, without the need for a data access to the machine control. It is based on a sub-pixel accurate optical-flow-algorithm which determines information about the heads movement by means of the material flow in sequences of IR images. Using local curvatures in the temperature field of the IR images, feature matrices are created which can locally be compared to the features of successive images. Thus, the translation between images become visible. This enables the possibility to perform an accurate (16.8μm) and self-sufficient process monitoring that additionally is capable of capturing the motion and position information of the AFP system and can be linked to existing algorithms for defect detection and classification. © 2021, The Author(s)

Erhöhung der Klima-Resilienz in einem ökologischen Ackerbausystem: auf die Kombination von Strategien kommt es an!

Die Klimawandel-bedingte Zunahme von Trockenperioden in Gegenden mit geringen Niederschlägen erfordert Anpassungsstrategien im ökologischen Ackerbau. Außer trockenheitstoleranten Sorten wurden in einem Langzeitversuch auf einem viehlosen Ackerbaubetrieb in der semi-humiden Region im Osten Österreichs vier hauptsächliche Strategien gemeinsam angewandt: eine Futterleguminosen-basierte Fruchtfolge mit Zwischenfruchtgemengen, organische Düngung mit Luzernemulch, Biokompost oder Stallmist, reduzierte, nicht-wendende Bodenbearbeitung und Gehölzstrukturen. Mit diesen kombinierten Strategien waren die Humusgehalte stabil bis ansteigend, die Wasserinfiltration und pilzliche Biomasse im Oberboden wurden gefördert, die Erträge der Marktfrüchte waren überdurchschnittlich hoch und die Erträge einiger Kulturen waren auf der Leeseite einer Hecke positiv beeinflusst. Durch die Kombination dieser Strategien konnte der Wasserknappheit offensichtlich erfolgreich begegnet werden

Monitoring der Auswirkungen einer Umstellung auf den biologischen Landbau (MUBIL II). Abschlussbericht

Since 2003, a long-term field monitoring of the development of Organic Farming has been performed at the bio-farm “Rutzendorf“ in the Marchfeld region east of Vienna. The overall project focus includes three topics: (1) effects of organic farming on soil and plant characteristics depending on three organic fertilization systems (variant 1: green manure: mulching lucerne; variant 2: green manure plus communal compost; variant 3: farmyard manure: harvesting and removal of lucerne crop and cereal straw) (2) effects of hedges on micro climate, water capacity of the soils and crop performances, (3) analyses and cultivation of existing biotopes and establishment of new biotope structures, effects of biotopes and organic farming on the biodiversity of the farm. In the current phase of the project (MUBIL II, 2006 to March 2009), first effects of the conversion have been confirmed and new developments have occurred. (1) Soil monitoring in the period 2003 – 2008 has shown that the concentrations of plant available, CAL-extractable P and K pools remained in the range of “sufficient availability”. An investigation on five additional sites has shown that also for sites with long term organic farming (12 – 18 years) a sufficient or even high availability of P and K can be expected. This assumption is supported by the fact that in all studied soils a very large pool of organically bound phosphorous (which becomes plant available due to microbial degradation) has been detected. Measurements of the soil water balance showed that biologically farmed fields had higher soil water contents than conventional fields, especially in dry years. A significant impact of the kind of fertilization was not observed. Lucerne in the crop rotation had a positive influence on soil physical parameters like bulk density, saturated hydraulic conductivity, aggregate stability and the N mineralization potential. The densities and diversities of the soil fauna (oribatid and gamasid mites and springtails) were very low at the onset of the study in 2003. Except for the conventional site, the abundance and species richness of Collembola and Gamasida considerably increased in all organic land use types after an initial lag phase. Generally, the conversion to organic farming had a positive effect on Collembola and Gamasida; however, there was no discernible difference between three manure treatments. It is not yet clear if the resulting large numbers will sustain in the following years. Compared to the conventional managed field the number of weed species on the permanent plots is clearly higher but no continuous increase over the investigated years was detected. Under lucerne and under field pea the highest species numbers were found. Due to a decrease in numbers during the following years of the crop rotation, no problems for the practice are assumed. The different fertilizers have neither shown an effect on the emergence of weeds nor on the number of seeds. The yield of winter wheat following lucerne was significantly lower in variant 3 because of the removal of lucerne biomass in this system in contrast to the systems with lucerne mulching. No significantly positive effect of a fertilisation with communal compost and farmyard manure on crop yield has been detected. However, interesting results can be found by analysis of all fertilised trials of the last years. Overall, the fertilisation with farmyard manure (system 3) reached tendentiously the highest crop yields. The communal compost fertilisation did not show so constant results because of the lower nitrogen effect of the compost in contrast to the farmyard manure. The yield development of the three organic fertilization systems was confirmed by the results of nutrient and humus balances calculated with the agro software REPRO. The nutritional value of wheat from organic farms has been examined. Based on these results, it is recommended to conduct regular feed analysis, implying crude protein analysis at least, if home-grown grains are fed to livestock on organic farms. Variant 1 achieved the highest average gross margin during the six years period. The assumed costs for the organic manure in variant 2 and 3 could not be covered by higher revenues. The main influence on the level of the gross margin was, among the climatic conditions, the fluctuating prices of the cash crops during the sample period. (2) Field studies have shown a total sphere of influence of hedgerows in relation to their orientation, permeability and height of about the 15 to 20 fold of the height. Furthermore, available water resulting from precipitation, reduced evapotranspiration due to wind breaks or dislocation of snow has a high impact on (soil) water balance and hence on agriculture at this relatively dry location in Rutzendorf. The impact of the hedgerow lead to reduced water losses and higher soil water contents within a distance of 3 times the barrier height. These positive effects were higher in years with low precipitation amounts. Furthermore a positive effect of a hedge on crop yield in the adjacent field was shown. Yield increases ranged from 9.5 to 23.7 percent depending on the cultivated crop, the temperature and the amount of rain in the period of growth. (3) Hedges and tree rows on the farm proved to be species-poor and the structure is more and more degenerating. Therefore cultivation measures have been identified to improve the multi-functionality of landscape elements as well as biodiversity. These measures have been mapped in a preservation concept for the biotope structures. Along hedges and between fields 6 m broad “eco-stripes” were established. An increase in species diversity was achieved by sowing authochthonal wild flowers in one part of the stripes. In the other part of the stripes, which was left to natural succession, low diversity was recorded. A total of 139 species of wild bees was recorded in the project area Rutzendorf. The results show high diversity and rare species in five year old “eco-stripes” in the east. The species richness of two year old “eco-stripes” was also high, but only euryeicous species were found. Carabids and hoover flies were accumulated in and alongside the eco-stripes due to their rich blossom supply. By single-plant countings of pea aphids and their antagonists in three different distances of a flowering strip, lower aphid densities were recorded close to the eco-stripe. These could not be attributed to higher beneficial efficacy there. The spatial distribution of arthropod group numbers emphasizes the significance of hedges and eco-stripes for arthropod biodiversity. In 2006-2008, the territories of breeding birds in the research area Rutzendorf were censused using the mapping method. The impoverished breeding bird community was dominated by skylark and pheasant. Diversity and abundance of breeding birds have clearly increased since the beginning of the project in 2003

Monitoring der Umstellung auf den biologischen Landbau (MUBIL). Abschlussbericht

Auf dem Biobetrieb Rutzendorf der BVW GmbH im Marchfeld wurde ein umfassendes Langzeitmonitoring zur Entwicklung des biologischen Landbaus eingerichtet. Das interdisziplinäre Projekt hat 2003 begonnen und untersucht die wichtigsten Systemkomponenten in einem Agrarökosystem. Ziele des Projekts: (a) Feststellen der Wirkungen der Umstellung auf Boden und Pflanzen, (b) Vergleichen der Nachhaltigkeit von drei Düngungsvarianten, (c) Analysieren der Auswirkungen von Biotopstrukturen und der Bewirtschaftung auf die Biodiversität am Betrieb. Im ersten Projektjahr wurden die Monitoringflächen eingerichtet und die Ausgangssituation erhoben. Ein Einfluss der biologischen Bewirtschaftung und der Düngung auf die untersuchten Bodenparameter konnte mit Ausnahme der Aggregatstabilität noch nicht festgestellt werden. Erste Ertragsdifferenzen aufgrund der unterschiedlichen Düngung liegen vor. Die biologische Bewirtschaftung und die Anlage von Ökostreifen hat sich positiv auf die Biodiversität, sowohl der Fauna als auch der Flora, ausgewirkt. In der Nähe einer Hecke waren die Erträge und die Bodenwassergehalte höher als im freien Feld

Auswirkungen unterschiedlicher Haupt- und Zwischenfrucht-Kombinationen auf Ertrag und den Schaderregerbefall der Folgefrucht Kartoffel

Infections with diseases like black scurf (Rhizoctonia solani) and common scab (Strep-tomyces scabies) cause tuber blemishes. In addition, black scurf has an adverse impact on tuber yield, size and shape. The aim of the study was to assess the effect of combinations of main and catch crops on tuber yield, quality and sanitary status. The tested variants were: var. 1: pea without a catch crop apart from volunteer peas, var. 2: pea with a catch crop consisting of white mustard, California bluebell and volunteer peas, var. 3: oat without a catch crop, var. 4: oat with an underseed of white clover. Although in the variants tested no significant difference was achieved for tuber yield, disease occurrence and degree of infection with black scurf and common scab, ten-dentiously similar results were obtained for single variants and over the whole testing period. Highest tuber yields and lowest infection rates with the diseases under investi-gation were obtained for variant two

Representative structural element approach for assessing the mechanical properties of automated fibre placement-induced defects

In this paper, a 3D finite element modelling approach is presented to assess the effects of manufacturing defects within composite structures. The mesoscale modelling approach derives the stress-strain response of a composite structure from a representative structural element. A set of tensile and bending loads is used to compute its ABD-Matrix. The boundary conditions of the model are described in detail as is the extraction of the strain and curvature response. The derived stiffness from the presented modelling approach is compared to the classical lamination theory and the models' shortcomings are discussed. Finally, the influence of a gap, an overlap and two different-sized fuzzballs on the macroscopic mechanical properties of a composite structure are evaluated using the presented multiscale modelling approach, thereby providing stiffness matrices influenced by the defects for the use in global models of composite parts

Common patterns in type II restriction enzyme binding sites

Restriction enzymes are among the best studied examples of DNA binding proteins. In order to find general patterns in DNA recognition sites, which may reflect important properties of protein–DNA interaction, we analyse the binding sites of all known type II restriction endonucleases. We find a significantly enhanced GC content and discuss three explanations for this phenomenon. Moreover, we study patterns of nucleotide order in recognition sites. Our analysis reveals a striking accumulation of adjacent purines (R) or pyrimidines (Y). We discuss three possible reasons: RR/YY dinucleotides are characterized by (i) stronger H-bond donor and acceptor clusters, (ii) specific geometrical properties and (iii) a low stacking energy. These features make RR/YY steps particularly accessible for specific protein–DNA interactions. Finally, we show that the recognition sites of type II restriction enzymes are underrepresented in host genomes and in phage genomes

Sortenvergleich von Körner- und Futtererbsen in Reinsaat und Gemenge

Problemstellung/Ziele: Die Erbse gilt als die wichtigste Körnerleguminose im Ökologischen Landbau, sowohl in ihrer Funktion als Leguminose zur Versorgung des Betriebes mit Stickstoff, als auch für die Futterproduktion (Geflügel und Schweine). Unter der Annahme einer richtigen Stellung in der Fruchtfolge gelten der Ertrag, die Stickstoff-Fixierungsleistung sowie die Konkurrenzkraft gegenüber Beikraut als die wichtigsten Merkmale in der Entscheidungsfindung der Sortenauswahl. Für die Tierernährung ist die Proteinqualität, im engeren Sinn der Gehalt an essentiellen Aminosäuren entscheidend. Ziel dieses Projektes ist die Untersuchung verschiedener Erbsensorten bzw. -gemenge im Hinblick auf ihre Biomassebildung, Stickstoff Fixierleistung, Konkurrenzkraft gegenüber Beikräutern, Futtermittelparameter und Vorfruchtwert