94 research outputs found

    Water–Energy Nexus: Addressing Stakeholder Preferences in Jordan

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    The water and energy sectors are fundamentally linked. In Jordan, especially in the face of a changing climate, the water–energy nexus holds a number of challenges but also opportunities. A key point in exploring synergies is the identification of such, as well as the communication between the water and energy sectors. This paper promotes the importance of using a co-creative approach to help resolve opposing views and assessing stakeholder preferences in the context of the water–energy nexus in Jordan. A computer-supported, co-creative approach was used to evaluate stakeholder preferences and opinions on criteria and future scenarios for the energy and water sector in Jordan, identifying common difficulties and possibilities. The criteria describe socio-ecological aspects as well as techno-economic aspects for both systems. Discussing a set of preliminary scenarios describing possible energy and water futures ranked under a set of sector relevant criteria, a consensus between both stakeholder groups is reached. The robustness of results is determined, using a second-order probabilistic approach. The results indicate that there are no fundamental conflicts between the energy and water stakeholder groups. Applying a participatory multi-stakeholder, multi-criteria framework to the energy-water nexus case in Jordan promotes a clear understanding of where different stakeholder groups stand. This understanding and agreement can form the basis of a joint water–energy nexus policy used in the continued negotiation process between and within national and international cooperation, as well as promoting and developing acceptable suggestions to solve complex problems for both sectors

    Quantification and Evidence for Mechanically Metered Release of Pygidial Secretions in Formic Acid-Producing Carabid Beetles

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    This study is the first to measure the quantity of pygidial gland secretions released defensively by carabid beetles (Coleoptera: Carabidae) and to accurately measure the relative quantity of formic acid contained in their pygidial gland reservoirs and spray emissions. Individuals of three typical formic acid producing species were induced to repeatedly spray, ultimately exhausting their chemical compound reserves. Beetles were subjected to faux attacks using forceps and weighed before and after each ejection of chemicals. Platynus brunneomarginatus (Mannerheim) (Platynini), P. ovipennis (Mannerheim) (Platynini) and Calathus ruficollis Dejean (Sphodrini), sprayed average quantities with standard error of 0.313 ± 0.172 mg, 0.337 ± 0.230 mg, and 0.197 ± 0.117 mg per spray event, respectively. The quantity an individual beetle released when induced to spray tended to decrease with each subsequent spray event. The quantity emitted in a single spray was correlated to the quantity held in the reservoirs at the time of spraying for beetles whose reserves are greater than the average amount emitted in a spray event. For beetles with a quantity less than the average amount sprayed in reserve there was no significant correlation. For beetles comparable in terms of size, physiological condition and gland reservoir fullness, the shape of the gland reservoirs and musculature determined that a similar effort at each spray event would mechanically meter out the release so that a greater amount was emitted when more was available in the reservoir. The average percentage of formic acid was established for these species as 34.2%, 73.5% and 34.1% for for P. brunneomarginatus, P. ovipennis and C. ruficollis, respectively. The average quantities of formic acid released by individuals of these species was less than two-thirds the amount shown to be lethal to ants in previously published experiments. However, the total quantity from multiple spray events from a single individual could aggregate to quantities at or above the lethal level, and lesser quantities are known to act as ant alarm pheromones. Using a model, one directed spray of the formic acid and hydrocarbon mix could spread to an area of 5–8 cm diameter and persisted for 9–22 seconds at a threshold level known to induce alarm behaviors in ants. These results show that carabid defensive secretions may act as a potent and relatively prolonged defense against ants or similar predators even at a sub-lethal dose

    Multi-trait mimicry of ants by a parasitoid wasp

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    Many animals avoid attack from predators through toxicity or the emission of repellent chemicals. Defensive mimicry has evolved in many species to deceive shared predators, for instance through colouration and other morphological adaptations, but mimicry hardly ever seems to involve multi-trait similarities. Here we report on a wingless parasitoid wasp that exhibits a full spectrum of traits mimicing ants and affording protection against ground-dwelling predators (wolf spiders). In body size, morphology and movement Gelis agilis (Ichneumonidae) is highly similar to the black garden ant (Lasius niger) that shares the same habitat. When threatened, G. agilis also emits a volatile chemical that is similar to an ant-produced chemical that repels spiders. In bioassays with L. niger, G. agilis, G. areator, Cotesia glomerata and Drosophila melanogaster, ants and G. agilis were virtually immune to spider attack, in contrast the other species were not. Volatile characterisation with gas chromatography-mass spectrometry identified G. agilis emissions as 6-methyl-5-hepten-2-one, a known insect defence semiochemical that acts as an alarm pheromone in ants. We argue that multi-trait mimicry, as observed in G. agilis, might be much more common among animals than currently realized

    It’s Not a Bug, It’s a Feature: Functional Materials in Insects

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    Over the course of their wildly successful proliferation across the earth, the insects as a taxon have evolved enviable adaptations to their diverse habitats, which include adhesives, locomotor systems, hydrophobic surfaces, and sensors and actuators that transduce mechanical, acoustic, optical, thermal, and chemical signals. Insect‐inspired designs currently appear in a range of contexts, including antireflective coatings, optical displays, and computing algorithms. However, as over one million distinct and highly specialized species of insects have colonized nearly all habitable regions on the planet, they still provide a largely untapped pool of unique problem‐solving strategies. With the intent of providing materials scientists and engineers with a muse for the next generation of bioinspired materials, here, a selection of some of the most spectacular adaptations that insects have evolved is assembled and organized by function. The insects presented display dazzling optical properties as a result of natural photonic crystals, precise hierarchical patterns that span length scales from nanometers to millimeters, and formidable defense mechanisms that deploy an arsenal of chemical weaponry. Successful mimicry of these adaptations may facilitate technological solutions to as wide a range of problems as they solve in the insects that originated them.Insects have evolved manifold optimized solutions to everyday problems. The diversity and precision of their hierarchical material adaptations often outsmart and outperform current man‐made approaches. These materials hence provide an excellent basis for the inspiration of new technological approaches by taking design cues from nature’s solutions.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/143760/1/adma201705322.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/143760/2/adma201705322_am.pd

    Chemische Ökologie

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    Transformation of steroids by Bacillus strains isolated from the foregut of water beetles (Coleoptera: Dytiscidae): I. Metabolism of androst-4-en-3,17-dione (AD)

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    Two Bacillus strains were isolated from the foregut of the water beetle Agabus affinis (Payk.) and tested for their steroid transforming ability. After incubation with androst-4- en-3,17-dione (AD), 13 different transformation products were detected. A

    Chemische Ökologie

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    Chemical defense ofEudia (Saturnia) pavonia caterpillars

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