9 research outputs found

    Structure and functions of the ventral tube of the clover springtail Sminthurus viridis (Collembola Sminthuridae)

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    YesSpringtails (Collembola) are unique in Hexapoda for bearing a ventral tube (collophore) on the first abdominal segment. Although numerous studies have been conducted on the functions of the ventral tube, its fine structure has not been thoroughly elucidated to date. In this paper, we observed the jumping behavior of the clover springtail Sminthurus viridis (Linnaeus, 1758) and dissected the ventral tube using light microscopy to elucidate the fine structure and the possible function of the ventral tube. The results show that a pair of eversible vesicles can be extended from the apical opening of the ventral tube. The eversible vesicles are furnished with numerous small papillae, and can be divided into a basal part and a distal part. The eversible vesicles have a central lumen connected to the tiny papillae and leading to the body cavity. The eversible vesicles can reach any part of the body, and may serve as following functions: (a) absorbing moisture; (b) uptaking water; (c) cleaning the body surface; and (d) fastening the body on a smooth surface

    Rekreacyjne używanie leków dostępnych w odręcznej sprzedaży: odurzanie i doping mózgu

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    Recreational substance use is becoming more common, especially among young people. Some anti-inflammatory or antitussive drugs exert potent psychoactive effects when they are used in large doses. Easily available over-the-counter (OTC) drugs may cause a range of effects including hallucinations or euphoria. Dextromethorphan (DXM) is particularly often used. At doses of 1.5–7.5 mg/kg body mass it induces stimulation, mood improvement, motor impairment, and used at doses higher than 7.5 mg/kg b.m., it exerts dissociative effects. Adverse reactions are especially clear when DXM was taken with alcohol or substances affecting metabolic activity of cytochrome P450 CYP2D6. Among DXM users, some cases of psychological dependence and withdrawal symptoms were observed. Long-term use of DXM may be associated with cognitive function deterioration. The abuse of Tantum Rosa (a popular gynecological anti-inflammatory drug containing benzydamine) was described mainly in Brazil, Poland and Romania. It causes hallucinations (mainly visual) and “flashbacks” (short-term hallucinations despite not being under the influence of the psychedelic compound). Pseudoephedrine, an amphetamine-like stimulant, produces mood improvement or even euphoria, hallucinations and psychosis. However, the real health threat is associated with the use of substances produced from pseudoephedrine: ephedrone and methamphetamine

    Detection and Recognition of Environmental Sounds by Musicians and Non-Musicians

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    The article reports three experiments conducted to determine whether musicians possess better ability of recognising the sources of natural sounds than non-musicians. The study was inspired by reports which indicate that musical training develops not only musical hearing, but also enhances various non-musical auditory capabilities. Recognition and detection thresholds were measured for recordings of environment al sounds presented in quiet (Experiment 1) and in the background of a noise masker (Experiment 2). The listener’s ability of sound source recognition was inferred from the recognition-detection threshold gap (RDTG) defined as the difference in signal level between the thresholds of sound recognition and sound detection. Contrary to what was expected from reports of enhanced auditory abilities of musicians, the RDTGs were not smaller for musicians than for non-musicians. In Experiment 3, detection thresholds were measured with an adaptive procedure comprising three interleaved stimulus tracks with different sounds. It was found that the threshold elevation caused by stimulus interleaving was similar for musicians and non-musicians. The lack of superiority of musicians over non-musicians in the auditory tasks Explorer in this study is explained in terms of a listening strategy known as casual listening mode, which is a basis for auditory orientation in the environment

    Allgemeine operative Probleme. Vor- und Nachbehandlung. Komplikationen. Expulsive Blutung. Wirkungsweise

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