105 research outputs found

    Communicating canine and human emotions

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    Kujala (2017) reviews a topic of major relevance for the understanding of the special dog-human relationship: canine emotions (as seen through human social cognition). This commentary draws attention to the communication of emotions within such a particular social context. It highlights challenges that need to be tackled to further advance research on emotional communication, and it calls for new avenues of research. Efforts to disentangle emotional processes from cognitive functioning might be necessary to better comprehend how they contribute, alone and/or in combination, to the communication of emotions. Also, new research methods need to be developed to account for the rich sensory repertoire of dogs, likely involved in emotional communication

    Influence of Sodium Chloride on the Formation and Dissociation Behavior of CO2 Gas Hydrates

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    We present an experimental study on the formation and dissociation characteristics of carbon dioxide (CO2) gas hydrates using Raman spectroscopy. The CO2 hydrates were formed from sodium chloride/water solutions with salinities of 0–10 wt %, which were pressurized with liquid CO2 in a stirred vessel at 6 MPa and a subcooling of 9.5 K. The formation of the CO2 hydrate resulted in a hydrate gel where the solid hydrate can be considered as the continuous phase that includes small amounts of a dispersed liquid water-rich phase that has not been converted to hydrate. During the hydrate formation process we quantified the fraction of solid hydrate, xH, and the fraction of the dispersed liquid water-rich phase, xL, from the signature of the hydroxyl (OH)-stretching vibration of the hydrate gel. We found that the fraction of hydrate xH contained in the hydrate gel linearly depends on the salinity of the initial liquid water-rich phase. In addition, the ratio of CO2 and water was analyzed in the liquid water-rich phase before hydrate formation, in the hydrate gel during growth and dissociation, and after its complete dissociation again in the liquid water-rich phase. We observed a supersaturation of CO2 in the water-rich phase after complete dissociation of the hydrate gel and were able to show that the excess CO2 exists as dispersed micro- or nanoscale liquid droplets in the liquid water-rich phase. These residual nano- and microdroplets could be a possible explanation for the so-called memory effect

    A Raman technique applicable for the analysis of the working principle of promoters and inhibitors of gas hydrate formation

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    We report a Raman technique applicable for the in situ analysis of the development of hydrogen bonds in the liquid water‐rich phase just before the onset of gas hydrate formation. Herewith, the phase transition as well as the working principle of hydrate formation inhibitors and promoters can be analyzed

    Good Timing Matters: The Spatially Fractionated High Dose Rate Boost Should Come First.

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    Monoplanar microbeam irradiation (MBI) and pencilbeam irradiation (PBI) are two new concepts of high dose rate radiotherapy, combined with spatial dose fractionation at the micrometre range. In a small animal model, we have explored the concept of integrating MBI or PBI as a simultaneously integrated boost (SIB), either at the beginning or at the end of a conventional, low-dose rate schedule of 5x4 Gy broad beam (BB) whole brain radiotherapy (WBRT). MBI was administered as array of 50 ”m wide, quasi-parallel microbeams. For PBI, the target was covered with an array of 50 ”m × 50 ”m pencilbeams. In both techniques, the centre-to-centre distance was 400 ”m. To assure that the entire brain received a dose of at least 4 Gy in all irradiated animals, the peak doses were calculated based on the daily BB fraction to approximate the valley dose. The results of our study have shown that the sequence of the BB irradiation fractions and the microbeam SIB is important to limit the risk of acute adverse effects, including epileptic seizures and death. The microbeam SIB should be integrated early rather than late in the irradiation schedule

    Microbeam Irradiation as a Simultaneously Integrated Boost in a Conventional Whole-Brain Radiotherapy Protocol.

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    Microbeam radiotherapy (MRT), an experimental high-dose rate concept with spatial fractionation at the micrometre range, has shown a high therapeutic potential as well as good preservation of normal tissue function in pre-clinical studies. We investigated the suitability of MRT as a simultaneously integrated boost (SIB) in conventional whole-brain irradiation (WBRT). A 174 Gy MRT SIB was administered with an array of quasi-parallel, 50 ”m wide microbeams spaced at a centre-to-centre distance of 400 ”m either on the first or last day of a 5 × 4 Gy radiotherapy schedule in healthy adult C57 BL/6J mice and in F98 glioma cell cultures. The animals were observed for signs of intracranial pressure and focal neurologic signs. Colony counts were conducted in F98 glioma cell cultures. No signs of acute adverse effects were observed in any of the irradiated animals within 3 days after the last irradiation fraction. The tumoricidal effect on F98 cell in vitro was higher when the MRT boost was delivered on the first day of the irradiation course, as opposed to the last day. Therefore, the MRT SIB should be integrated into a clinical radiotherapy schedule as early as possible

    MinRessource: Nachhaltiges Ressourcenmanagement von mineralischen PrimĂ€r- und SekundĂ€rbaustoffen: Sachstandsanalyse und Stoffstromentwicklung unter BerĂŒcksichtigung der Genehmigungssituation in Sachsen (Modul I)

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    Die BroschĂŒre enthĂ€lt die Analyse der derzeitigen Entsorgungssituation mineralischer Bau- und AbbruchabfĂ€lle im Freistaat Sachsen und liefert eine AbschĂ€tzung der Stoffstromentwicklung innerhalb der Verwertung und der Beseitigung verschiedener Abfallfraktionen

    Life as a fortress – structure, function, and adaptive values of morphological and chemical defense in the oribatid mite Euphthiracarus reticulatus (Actinotrichida)

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    Background: Oribatid mites are among the primordial decomposer faunal elements and potential prey organisms insoil. Among their myriad morphological defenses are strong sclerotization and mineralization, cuticular tecta, and the “ptychoid” body-form, which allows to attain an encapsulated, seed-like appearance. Most oribatid mites possess a pair of exocrine glands that produce blends of hydrocarbons, terpenes, aromatics, alkaloids and cyanogenic compounds.Many species evolved “holistic” defensive strategies by combining several morphological and chemical traits. Methods: We describe the morphological and chemical bases of defense in the ptychoid oribatid Euphthiracarus reticulatus. The functional morphology was investigated with synchrotron X-ray microtomography (SRÎŒCT) and highspeed life-radiography. Gland secretions were collected from 20,000 adult specimens, purified and fractionated by preparative capillary gas chromatography (pcGC) and analyzed by gas chromatography / mass spectrometry (GC/MS), high-resolution mass spectrometry (HRMS), and nuclear magnetic resonance spectroscopy (NMR). The adaptive values of morphological and chemical defenses were estimated in bioassays against three predators: a similar-sized gamasid mite (Stratiolaelaps miles, ca. 0.8 mm, with slender chelicera for piercing membranous cuticular regions), and two larger staphylinid beetles, Stenus juno (ca. 7 mm, bearing a harpoon-like sticky labium and sickle-shaped mandibles) and Othius punctulatus (ca. 14 mm, bearing plesiomorphic chewing mandibles). Results: The secretions comprised two components: the diterpene ÎČ-springene and a novel compound with a mass of 276 g/mol – eventually elucidated as 2-(but-1-en-1-yl)-4-butylidene-3-(pent-2-en-1-yl)-pentanedial, to which we assign the trivial name ÎŽ-acaridial. Upon attacks by S. juno, E. reticulatus reacted quickly: within 150 ms from the first contact the encapsulation was almost completed – less time than the beetle needed to retract the labium and transfer the mite to the mandibles. Chemically-defended specimens of E. reticulatus effectively repelled all predators. After depletion of oil-gland reservoirs, however, O. punctulatus easily fed on the mites while S. miles and S. juno were not able to overcome the morphological barrier of strong cuticle and ptychoid body form. Conclusion: Such an effective, holistic defense strategy, involving both morphological and chemical traits, probably carries high resource-costs, but it allows adult euphthiracaroid mites to occupy an almost “enemy-free space” despite the high diversity of predators in soil

    Life as a fortress structure, function, and adaptive values of morphological and chemical defense in the oribatid mite Euphthiracarus reticulatus (Actinotrichida)

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    Background Oribatid mites are among the primordial decomposer faunal elements and potential prey organisms in soil. Among their myriad morphological defenses are strong sclerotization and mineralization, cuticular tecta, and the “ptychoid” body-form, which allows to attain an encapsulated, seed-like appearance. Most oribatid mites possess a pair of exocrine glands that produce blends of hydrocarbons, terpenes, aromatics, alkaloids and cyanogenic compounds. Many species evolved “holistic” defensive strategies by combining several morphological and chemical traits. Methods We describe the morphological and chemical bases of defense in the ptychoid oribatid Euphthiracarus reticulatus. The functional morphology was investigated with synchrotron X-ray microtomography (SRCT) and high-speed life-radiography. Gland secretions were collected from 20,000 adult specimens, purified and fractionated by preparative capillary gas chromatography (pcGC) and analyzed by gas chromatography / mass spectrometry (GC/MS), high-resolution mass spectrometry (HRMS), and nuclear magnetic resonance spectroscopy (NMR). The adaptive values of morphological and chemical defenses were estimated in bioassays against three predators: a similar-sized gamasid mite (Stratiolaelaps miles, ca. 0.8 mm, with slender chelicera for piercing membranous cuticular regions), and two larger staphylinid beetles, Stenus juno (ca. 7 mm, bearing a harpoon-like sticky labium and sickle-shaped mandibles) and Othius punctulatus (ca. 14 mm, bearing plesiomorphic chewing mandibles). Results The secretions comprised two components: the diterpene -springene and a novel compound with a mass of 276 g/mol eventually elucidated as 2-(but-1-en-1-yl)-4-butylidene-3-(pent-2-en-1-yl)-pentanedial, to which we assign the trivial name -acaridial. Upon attacks by S. juno, E. reticulatus reacted quickly: within 150 ms from the first contact the encapsulation was almost completed less time than the beetle needed to retract the labium and transfer the mite to the mandibles. Chemically-defended specimens of E. reticulatus effectively repelled all predators. After depletion of oil-gland reservoirs, however, O. punctulatus easily fed on the mites while S. miles and S. juno were not able to overcome the morphological barrier of strong cuticle and ptychoid body form. Conclusion Such an effective, holistic defense strategy, involving both morphological and chemical traits, probably carries high resource-costs, but it allows adult euphthiracaroid mites to occupy an almost “enemy-free space” despite the high diversity of predators in soil.(VLID)286348
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