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Abstract: An important goal in toxicology is the development of new ways to increase the speed, accuracy, and applicability of chemical hazard and risk assessment approaches. A promising route is the integration of in vitro assays with biological pathway information. We examined how the adverse outcome pathway (AOP) framework can be used to develop pathway-based quantitative models useful for regulatory chemical safety assessment. By using AOPs as initial conceptual models and the AOP knowledge base as a source of data on key event relationships, different methods can be applied to develop computational quantitative AOP models (qAOPs) relevant for decision making. A qAOP model may not necessarily have the same structure as the AOP it is based on. Useful AOP modeling methods range from statistical, Bayesian networks, regression, and ordinary differential equations to individual-based models and should be chosen according to the questions being asked and the data available. We discuss the need for toxicokinetic models to provide linkages between exposure and qAOPs, to extrapolate from in vitro to in vivo, and to extrapolate across species. Finally, we identify best practices for modeling and model building and the necessity for transparent and comprehensive documentation to gain confidence in the use of qAOP models and ultimately their use in regulatory applications. Environ Toxicol Chem 2019;38:1850–1865. © 2019 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC.
Keywords: Quantitative Adverse Outcome pathways, TKTD modelling, alternatives to animal testing, predictive toxicology, species extrapolation, prioritization of chemicals
Published in DiRROS: 06.08.2024; Views: 18; Downloads: 13
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Abstract: Sexual communication in animals often involves duetting characterized by a coordinated reciprocal exchange of acoustic signals. We used playback experiments to study the role of timing of a female reply in the species-specific duet structure in the leafhopper Aphrodes makarovi (Hemiptera: Cicadellidae). In leafhoppers, mate recognition and location is mediated exclusively by species- and sex-specific substrate-borne vibrational signals and a female signal emitted in reply to male advertisement calls is essential for recognition and successful location of the female. In A. makarovi, males have to initiate each exchange of vibrational signals between partners, and in a duet the beginning of a female reply overlaps the end of the male advertisement call. Results of playback treatments in which female replies were delayed and did not overlap with the male call revealed that in order to trigger an appropriate behavioural response of the male, female reply has to appear in a period less than 400 ms after the end of the initiating male call. Results also suggest that males are not able to detect a female reply while calling, since female reply that did not continue after the end of male call triggered male behaviour similar to behaviour observed in the absence of female reply. Together, our results show that vibrational duets are tightly coordinated and that the species-specific duet structure plays an important role in mate recognition in location processes.
Keywords: vibration, insects, bioacoustics, animal signaling and communication
Published in DiRROS: 29.07.2024; Views: 91; Downloads: 56
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Abstract: In animal contests, communicating aggressive motivation is most often mediated by visual or acoustic signals, while chemical signals are not expected to serve such a function since they are less able to be modulated by the sender during the changing behavioral context. We describe a rare example of ephemeral olfactory signals in terrestrial animals, signals that are emitted via protrusive scent glands in male cave crickets Troglophilus neglectus (Orthoptera, Rhaphidophoridae) to reflect the state of the signaler’s aggression. We correlate the intensity of behaviorally expressed aggression of the individuals in dyadic contests with the frequency and extent of their gland tissue protrusion, the latter serving as an indication of the amount of released odor. We detected large amounts of odor release during brief gland protrusions, and the absence of its release during gland retraction. Males protruded the glands during and after encountering a rival, with the degree of protrusion increasing with the intensity of the signalers’ aggression. During the encounters, the degree of gland protrusion increased most strongly with the occurrence of the elevated body posture, directly preceding the attack. This degree was significantly higher in encounter winners than in losers displaying such posture, suggesting the highly important role of the released odor for contest resolution. After the encounters, glands were protruded almost exclusively by winners, apparently announcing victory. We tested for the function of the olfactory signals also directly, by preventing gland tissue protrusion in symmetric and asymmetric treatments of the contestants. Treating only the dominant individuals decreased the percentage of encounters they won by over 60%, while treating both contestants elicited a significant increase in the frequency and duration of fights. During contests, the olfactory signals of T. neglectus apparently function as a highly effective threat, which prevents maximal contest escalation and decreases the conflict-related costs.
Keywords: animal behaviour, bioacoustics, aggression
Published in DiRROS: 25.07.2024; Views: 88; Downloads: 93
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Keywords: brain tumors, tumor microenvironment, animal models, xenotransplantation
Published in DiRROS: 09.05.2024; Views: 221; Downloads: 466
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Abstract: This essay is an attempt to propose an outline of a new respiratory animal philosophy. Based on an analysis of the forgetting of breath in Western philosophy, it aims to gesture towards a future, breathful and compassionate world of co-sharing and co-breathing. In the first part, the basic features of forgetting of breath are explained based on David Abram’s work in respiratory ecophilosophy. This part also introduces an important contribution to modern philosophy by Ludwig Klages. The second part is dedicated to reflections on what I understand as an unfortunate transition from soul and pneuma to spirit and Geist. Based on these analyses, I proceed towards an idiosyncratic thought on the nocturnal mystery of pneuma, with references to ancient Upanishadic and 20th-century phenomenological Levinasian thought. Based on these teachings, I argue that, at the bottom of her existence, the subject is a lung partaking in an immense external lung (Merleau-Ponty). In the fourth part of the essay, I extend my reflections toward comparative animal respiratory phenomenology and argue for the immense compassion for all our fellow breathing beings. Finally, in the concluding, fifth part of this essay, I am arguing for a future biocentric and breathful environment, signifying and bringing a new compassionate-respiratory alliance into the world.
Keywords: pneuma, psyche, breath, animal breath, respiratory phenomenology, environmental philosophy
Published in DiRROS: 07.03.2024; Views: 243; Downloads: 132
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