Kosten und externe Effekte des künstlichen Lichts sowie Ansätze der ökonomischen Bewertung

Printausgabe unter ISBN 978-3-7983-2502-9 erschienenDer vorliegende Band wurde im Rahmen des Teilprojekts 5 "Kosten des Verlusts der Nacht – Eine ökonomische Analyse der Folgen nächtlicher Beleuchtung" als Literaturbericht der ersten Projektphase erstellt. Der Text stellt einen Überblick über den Forschungsstand zu den direkten Kosten der zunehmenden künstlichen nächtlichen Beleuchtung sowie zu näherungsweisen Bewertungen von ökonomischen Wirkungen der externen Kosten zum Stand Ende 2011 dar

Evaluation of soil EDTA applications on crop performance and uptake of macro- and micronutrients by agricultural crops

Chelatoren wie das Ethylenediamintetraessigsäure (EDTA) gelangen über unterschiedliche Kontaminationspfade in die Umwelt. Dennoch wurde bislang die Wirkung von EDTA auf das Pflanzenwachstum im Allgemeinen und die Wirkung auf die Mineralstoffversorgung im Besonderen nur unzureichend erforscht. In einem Gefäßversuch wurde daher der Einfluss steigender EDTA Konzentrationen auf das Wachstum sowie die Aufnahme von Haupt- und Spurenelementen bei unterschiedlichen Kulturpflanzen untersucht. Die Sensitivität der untersuchten Kulturpflanzen hinsichtlich EDTA sank in der Reihenfolge Sonnenblume > Raps > Mais. Mais reagierte also am wenigsten sensitiv auf eine Behandlung mit EDTA und zeigte keine visuellen Symptome, die Hinweis auf eine EDTA Toxizität geben würden. Der Biomasseertrag war jedoch bei Mais in der höchsten EDTA Stufe deutlich reduziert. Im Vergleich dazu wurden an Winterraps und Sonnenblume nekrotische Läsionen in Verbindung mit EDTA festgestellt und die Biomasseentwicklung war signifikant reduziert, wenn EDTA dem Boden in höheren Mengen zugesetzt wurde.Die Aufnahme von Mangan (Mn) und Zink (Zn) in den Spross wurde bei allen drei untersuchten Kulturen durch die Applikation von EDTA zum Boden signifikant erhöht. Mn and Zn wurden auch stärker in die Wurzel aufgenommen, nur beim Raps wurde eine signifikant geringere Mn Aufnahme in die Wurzel in Verbindung mit EDTA festgestellt. Bei Mais wurden nicht nur Mn und Zn verstärkt in den Spross aufgenommen, wenn EDTA appliziert wurde, sondern auch alle anderen untersuchten Spurenelemente mit Ausnahme von Kupfer (Cu). Bei Raps zeigten sich unter­schiedliche Trends: während die Aufnahme von Cu, Mn und Zn in den Spross durch EDTA Applikation erhöht wurde, sank gleichzeitig der Gehalt an Eisen (Fe), Mn und Molybdän (Mo) in den Wurzeln. Bei der Sonnen­blume zeigten sich ähnliche Veränderungen in der Spu­ren­elementaufnahme wie beim Raps, nur der Mn Gehalt in der Wurzel stieg im Gegensatz zu Raps mit EDTA Appli­kation an. EDTA hatte nicht nur einen starken Einfluss auf die Verfügbarkeit der Spurenelemente, sondern beeinflusste auch die Aufnahme an Hauptnährelementen signifikant. DOI: 10.5073/JfK.2016.03.02, https://doi.org/10.5073/JfK.2016.03.02Chelates such as ethylenediaminetetraacetic acid (EDTA) enter the environment from various sources but its impact on crop growth and mineral uptake has been evaluated only sporadically. In a pot experiment with graded EDTA applications the impact of free EDTA on crop performance, macro- and microelement uptake was assessed. The sensitivity towards EDTA decreased from sunflower > oilseed rape > maize. Maize was the least sensitive crop showing no visual toxicity symptoms, however, a reduction in biomass development. In comparison, oilseed rape and sunflower displayed necrotic lesions on their leaves and biomass development was significantly reduced when higher rates of EDTA were applied. Soil EDTA appli­cation increased the uptake of Mn and Zn in shoots of all three crops and in roots of maize and sunflower. In maize EDTA increased not only the uptake of Mn and Zn, but also all other investigated micronutrients in shoots with the only exception of copper. In oilseed rape EDTA applications increased the uptake of Cu, Mn and Zn in shoots while the Fe, Mn and Mo content decreased in roots. Changes in the micronutrient content in shoots of sunflowers were similar to that in oilseed rape. In roots EDTA increased the Mn uptake. Next to micronutrients EDTA influenced the macronutrient uptake of the tested crop plants. DOI: 10.5073/JfK.2016.03.02, https://doi.org/10.5073/JfK.2016.03.0

Single cell analysis applied to antibody fragment production with Bacillus megaterium: development of advanced physiology and bioprocess state estimation tools

<p>Abstract</p> <p>Background</p> <p>Single cell analysis for bioprocess monitoring is an important tool to gain deeper insights into particular cell behavior and population dynamics of production processes and can be very useful for discrimination of the real bottleneck between product biosynthesis and secretion, respectively.</p> <p>Results</p> <p>Here different dyes for viability estimation considering membrane potential (DiOC₂(3), DiBAC₄(3), DiOC₆(3)) and cell integrity (DiBAC₄(3)/PI, Syto9/PI) were successfully evaluated for <it>Bacillus megaterium </it>cell characterization. It was possible to establish an appropriate assay to measure the production intensities of single cells revealing certain product secretion dynamics. Methods were tested regarding their sensitivity by evaluating fluorescence surface density and fluorescent specific concentration in relation to the electronic cell volume. The assays established were applied at different stages of a bioprocess where the antibody fragment D1.3 scFv production and secretion by <it>B. megaterium </it>was studied.</p> <p>Conclusions</p> <p>It was possible to distinguish between live, metabolic active, depolarized, dormant, and dead cells and to discriminate between high and low productive cells. The methods were shown to be suitable tools for process monitoring at single cell level allowing a better process understanding, increasing robustness and forming a firm basis for physiology-based analysis and optimization with the general application for bioprocess development.</p

The First Step of Neurospora crassa Molybdenum Cofactor Biosynthesis: Regulatory Aspects under N-Derepressing and Nitrate-Inducing Conditions

Molybdenum cofactor (Moco) is the active site prosthetic group found in all Moco dependent enzymes, except for nitrogenase. Mo-enzymes are crucial for viability throughout all kingdoms of life as they catalyze a diverse set of two electron transfer reactions. The highly conserved Moco biosynthesis pathway consists of four different steps in which guanosine triphosphate is converted into cyclic pyranopterin monophosphate, molybdopterin (MPT), and subsequently adenylated MPT and Moco. Although the enzymes and mechanisms involved in these steps are well characterized, the regulation of eukaryotic Moco biosynthesis is not. Within this work, we described the regulation of Moco biosynthesis in the filamentous fungus Neurospora crassa, which revealed the first step of the multi-step pathway to be under transcriptional control. We found, that upon the induction of high cellular Moco demand a single transcript variant of the nit-7 gene is increasingly formed pointing towards, that essentially the encoded enzyme NIT7-A is the key player for Moco biosynthesis activity in Neurospora

The Molybdenum Cofactor Biosynthesis Network: In vivo Protein-Protein Interactions of an Actin Associated Multi-Protein Complex

Survival of plants and nearly all organisms depends on the pterin based molybdenum cofactor (Moco) as well as its effective biosynthesis and insertion into apo-enzymes. To this end, both the central Moco biosynthesis enzymes are characterized and the conserved four-step reaction pathway for Moco biosynthesis is well-understood. However, protection mechanisms to prevent degradation during biosynthesis as well as transfer of the highly oxygen sensitive Moco and its intermediates are not fully enlightened. The formation of protein complexes involving transient protein-protein interactions is an efficient strategy for protected metabolic channelling of sensitive molecules. In this review, Moco biosynthesis and allocation network is presented and discussed. This network was intensively studied based on two in vivo interaction methods: bimolecular fluorescence complementation (BiFC) and split-luciferase. Whereas BiFC allows localisation of interacting partners, split-luciferase assay determines interaction strengths in vivo. Results demonstrate (i) interaction of Cnx2 and Cnx3 within the mitochondria and (ii) assembly of a biosynthesis complex including the cytosolic enzymes Cnx5, Cnx6, Cnx7, and Cnx1, which enables a protected transfer of intermediates. The whole complex is associated with actin filaments via Cnx1 as anchor protein. After biosynthesis, Moco needs to be handed over to the specific apo-enzymes. A potential pathway was discovered. Molybdenum-containing enzymes of the sulphite oxidase family interact directly with Cnx1. In contrast, the xanthine oxidoreductase family acquires Moco indirectly via a Moco binding protein (MoBP2) and Moco sulphurase ABA3. In summary, the uncovered interaction matrix enables an efficient transfer for intermediate and product protection via micro-compartmentation

Look Before You Leap: Improving the Users’ Ability to Detect Fraud in Electronic Marketplaces

Reputation systems in current electronic marketplaces can easily be manipulated by malicious sellers in order to appear more reputable than appropriate. We conducted a controlled experiment with 40 UK and 41 German participants on their ability to detect malicious behavior by means of an eBay-like feedback profile versus a novel interface involving an interactive visualization of reputation data. The results show that participants using the new interface could better detect and understand malicious behavior in three out of four attacks (the overall detection accuracy 77% in the new vs. 56% in the old interface). Moreover, with the new interface, only 7% of the users decided to buy from the malicious seller (the options being to buy from one of the available sellers or to abstain from buying), as opposed to 30% in the old interface condition

Surviving Volcanic Environments — Interaction of Soil Mineral Content and Plant Element Composition

Different plant species were investigated fromtwo Aeolian Islands located in close vicinity, one with fumarolic activity (Vulcano) and one without (Lipari). On Vulcano, elevated concentrations of SO2/H2S determined in ambient air indicated the need of plants to adapt to harmful sulphur concentrations by detoxification strategies. The current study was focused on evaluating the element composition of plant leaves in relation to soil mineral contents. The soil of Volcano was characterised by a significantly lower pH on all three sampling sites as well as very high amounts of sulphur and plant available sulphate due to volcanic activities, compared to Lipari. By contrast, a general difference in the composition of trace elements in the soil was not observed between the islands, apart from arsenic, which was increased at all three sampling sites on Vulcano. Element accumulation in the leaves differed between the two islands. The tested species showed a significant higher accumulation of numerous elements (Al, B, Fe, K, Mg, Mn, Ni, and Zn) on Vulcano compared to Lipari, while excluding Ca and Mo. These differences in element accumulation in the leaves between the islands may be caused by the lower soil pH on Vulcano. Extreme sulphur accumulation was found for all tested species on Vulcano, but was lower in woody species with higher dry matter content compared to herbaceous species with lower dry matter content. This caused a significantly negative correlation between plant sulphur and dry matter content. From these results, it is concluded that species with higher dry matter contents possess a more effective protection against extreme sulphur accumulation. Strategies to cope with other potentially toxic elements in the soil ranged from exclusion to hyper-accumulation. Hierarchical cluster analyses of the leaf element content revealed a clear separation between two groups: First, herbaceous perennial plants as strong accumulators; and second, woody perennial plants such as shrubs or trees as less strong accumulators, with the primordial species Fumaria capreolata representing an outside group

Sulfite Reductase Co-suppression in Tobacco Reveals Detoxification Mechanisms and Downstream Responses Comparable to Sulfate Starvation

Sulfite reductase (SIR) is a key enzyme in higher plants in the assimilatory sulfate reduction pathway. SIR, being exclusively localized in plastids, catalyzes the reduction of sulfite (SO32−) to sulfide (S2−) and is essential for plant life. We characterized transgenic plants leading to co-suppression of the SIR gene in tobacco (Nicotiana tabacum cv. Samsun NN). Co-suppression resulted in reduced but not completely extinguished expression of SIR and in a reduction of SIR activity to about 20–50% of the activity in control plants. The reduction of SIR activity caused chlorotic and necrotic phenotypes in tobacco leaves, but with varying phenotype strength even among clones and increasing from young to old leaves. In transgenic plants compared to control plants, metabolite levels upstream of SIR accumulated, such as sulfite, sulfate and thiosulfate. The levels of downstream metabolites were reduced, such as cysteine, glutathione (GSH) and methionine. This metabolic signature resembles a sulfate deprivation phenotype as corroborated by the fact that O-acetylserine (OAS) accumulated. Further, chlorophyll contents, photosynthetic electron transport, and the contents of carbohydrates such as starch, sucrose, fructose, and glucose were reduced. Amino acid compositions were altered in a complex manner due to the reduction of contents of cysteine, and to some extent methionine. Interestingly, sulfide levels remained constant indicating that sulfide homeostasis is crucial for plant performance and survival. Additionally, this allows concluding that sulfide does not act as a signal in this context to control sulfate uptake and assimilation. The accumulation of upstream compounds hints at detoxification mechanisms and, additionally, a control exerted by the downstream metabolites on the sulfate uptake and assimilation system. Co-suppression lines showed increased sensitivity to additionally imposed stresses probably due to the accumulation of reactive compounds because of insufficient detoxification in combination with reduced GSH levels

CPT and Lorentz Tests in Hydrogen and Antihydrogen

Signals for CPT and Lorentz violation at the Planck scale may arise in hydrogen and antihydrogen spectroscopy. We show that certain 1S-2S and hyperfine transitions can exhibit theoretically detectable effects unsuppressed by any power of the fine-structure constant.Comment: 4 pages REVTeX, submitted for publicatio

An Integrated-Photonics Optical-Frequency Synthesizer

Integrated-photonics microchips now enable a range of advanced functionalities for high-coherence applications such as data transmission, highly optimized physical sensors, and harnessing quantum states, but with cost, efficiency, and portability much beyond tabletop experiments. Through high-volume semiconductor processing built around advanced materials there exists an opportunity for integrated devices to impact applications cutting across disciplines of basic science and technology. Here we show how to synthesize the absolute frequency of a lightwave signal, using integrated photonics to implement lasers, system interconnects, and nonlinear frequency comb generation. The laser frequency output of our synthesizer is programmed by a microwave clock across 4 THz near 1550 nm with 1 Hz resolution and traceability to the SI second. This is accomplished with a heterogeneously integrated III/V-Si tunable laser, which is guided by dual dissipative-Kerr-soliton frequency combs fabricated on silicon chips. Through out-of-loop measurements of the phase-coherent, microwave-to-optical link, we verify that the fractional-frequency instability of the integrated photonics synthesizer matches the $7.0*10^{-13}$ reference-clock instability for a 1 second acquisition, and constrain any synthesis error to $7.7*10^{-15}$ while stepping the synthesizer across the telecommunication C band. Any application of an optical frequency source would be enabled by the precision optical synthesis presented here. Building on the ubiquitous capability in the microwave domain, our results demonstrate a first path to synthesis with integrated photonics, leveraging low-cost, low-power, and compact features that will be critical for its widespread use.Comment: 10 pages, 6 figure