Water mites (Hydrachnidia) of temporary ponds of Western Siberia: do the composition and the structure of acarofauna change over a long period of time?

2021 ◽  
Author(s):  
Vitaly A. Stolbov ◽  
Victoria V. Stolbova ◽  
Sergey D. Sheykin
Keyword(s):  
Western Siberia ◽  
Aquatic Organisms ◽  
Mite Species ◽  
Water Bodies ◽  
Temporary Ponds ◽  
Time Interval ◽  
Water Mites ◽  
Long Period ◽  
Freshwater Habitats ◽  
Long Time

Temporary ponds are specific freshwater habitats in which the characteristic fauna of aquatic organisms is formed. One of the large groups of invertebrates in temporary water bodies is water mites. In this work, water mites were studied in three different types of temporary ponds in the vicinity of the city of Tyumen, Western Siberia. The studies were carried out in two periods with a long time interval between them: in 2008–2010 and 2018–2019. In total, 33 species of water mites from 7 families were identified in the studied ponds. All ponds were dominated by vernal mite species typical for this type of water bodies. Also, they were characterized by similar seasonal dynamics of numbers. The species composition and the number of mites in different ponds varied, which is associated with different physicochemical parameters and the fauna of invertebrates, which served as food objects and hosts for the adults and larvae. Despite the small size and periodic drying of the ponds, the fauna of the mites inhabiting them has changed little over the long period of time that separates the studies. Only in one pond, which became permanent due to the rise of groundwater, significant changes in acarofauna were observed. Considering such constancy of the fauna of water mites of temporary ponds, they can be used as bioindicators of the ecological state of water bodies.

scholarly journals WATER MITES (ACARIFORMES: HYDRACHNIDIA, HALACAROIDEA) OF BOGS OF WESTERN SIBERIA (RUSSIA)

2018 ◽  
Vol 18 ◽  
pp. 102-109 ◽  
Author(s):  
Vitaly A. Stolbov ◽  
Victoria V. Popova ◽  
Sergei D. Sheikin ◽  
Sergei S. Tupitsyn
Keyword(s):  
Species Diversity ◽  
Species Composition ◽  
Seasonal Dynamics ◽  
Western Siberia ◽  
Water Bodies ◽  
Water Mites ◽  
Sphagnum Bogs ◽  
Temporary Water Bodies ◽  
Temporary Water

Water mites (Acariformes, Hydrachnidia, Halacaroidea) were studied in 8 different bogs and fens of Western Siberia. 28 species of Hydrachnidia and 5 species of Halacaridae were found in them. The species composition in the bogs was very different. In the fens the abundance and species diversity were higher than in sphagnum bogs and the fauna were based on spring species. The representatives of the halacarid mites dominated in sphagnum bogs, which were not found in the fens. The specific similarity of the studied bogs was low. At the same time, the peculiarities of seasonal dynamics in bogs and fens were similar and resembled temporary water bodies: high numbers in the spring and an abruptly decline in the summer, with a slight increase in autumn.

An Adaptive and Learning System for Feedback-Controlled Evoked Response Studies

1981 ◽  
Vol 20 (03) ◽  
pp. 169-173
Author(s):  
J. Wagner ◽  
G. Pfurtscheixer
Keyword(s):  
Brain Activity ◽  
Evoked Response ◽  
Learning System ◽  
Time Interval ◽  
Electrical Brain Activity ◽  
Long Time ◽  
The Subject ◽  
Eeg Power ◽  
Stimulation System ◽  
Background Eeg

The shape, latency and amplitude of changes in electrical brain activity related to a stimulus (Evoked Potential) depend both on the stimulus parameters and on the background EEG at the time of stimulation. An adaptive, learnable stimulation system is introduced, whereby the subject is stimulated (e.g. with light), whenever the EEG power is subthreshold and minimal. Additionally, the system is conceived in such a way that a certain number of stimuli could be given within a particular time interval. Related to this time criterion, the threshold specific for each subject is calculated at the beginning of the experiment (preprocessing) and adapted to the EEG power during the processing mode because of long-time fluctuations and trends in the EEG. The process of adaptation is directed by a table which contains the necessary correction numbers for the threshold. Experiences of the stimulation system are reflected in an automatic correction of this table. Because the corrected and improved table is stored after each experiment and is used as the starting table for the next experiment, the system >learns<. The system introduced here can be used both for evoked response studies and for alpha-feedback experiments.

A description of two new species of water mites of the genus Torrenticola Piersig, 1896 (Acariformes: Hydrachnidia: Torrenticolidae) from the Krasnodar Kray, Russia

2013 ◽  
Vol 22 (2) ◽  
pp. 181-188
Author(s):  
P.V. Tuzovskij
Keyword(s):  
New Species ◽  
Mite Species ◽  
Running Waters ◽  
Water Mites ◽  
North Caucasus ◽  
Water Mite ◽  
The North ◽  
Two New Species

Two new water mite species, Torrenticola amplexella and T. krasnodarensis, from running waters of the North Caucasus (Krasnodar Kray) are described with illustrations.

scholarly journals Music for Monkeys: Building Methods to Design with White-Faced Sakis for Animal-Driven Audio Enrichment Devices

Animals ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1768
Author(s):  
Roosa Piitulainen ◽  
Ilyena Hirskyj-Douglas
Keyword(s):  
Longitudinal Study ◽  
Electronic Music ◽  
Computer Systems ◽  
Interactive System ◽  
Novelty Effect ◽  
Non Invasive ◽  
Long Period ◽  
Long Time ◽  
Audio System ◽  
Computer Interaction

Computer systems for primates to listen to audio have been researched for a long time. However, there is a lack of investigations into what kind of sounds primates would prefer to listen to, how to quantify their preference, and how audio systems and methods can be designed in an animal-focused manner. One pressing question is, if given the choice to control an audio system, would or could primates use such a system. In this study, we design an audio enrichment prototype and method for white-faced sakis that allows them to listen to different sounds in their regular zoo habitat while automatically logging their interactions. Focusing on animal-centred design, this prototype was built from low fidelity testing of different forms within the sakis’ enclosure and gathering requirements from those who care for and view the animal. This process of designing in a participatory manner with the sakis resulted in an interactive system that was shown to be viable, non-invasive, highly interactive, and easy to use in a zoo habitat. Recordings of the sakis’ interactions demonstrated that the sakis triggered traffic audio more than silence, rain sounds, zen, and electronic music. The data and method also highlight the benefit of a longitudinal study within the animals’ own environment to mitigate against the novelty effect and the day-to-day varying rhythm of the animals and the zoo environment. This study builds on animal-centred methods and design paradigms to allow the monitoring of the animals’ behaviours in zoo environments, demonstrating that useful data can be yielded from primate-controlled devices. For the Animal-Computer Interaction community, this is the first audio enrichment system used in zoo contexts within the animals own environment over a long period of time that gives the primate control over their interactions and records this automatically.

scholarly journals Optimal Perturbations of an Oceanic Vortex Lens

Fluids ◽  
2018 ◽  
Vol 3 (3) ◽  
pp. 63 ◽  
Author(s):  
Thomas Meunier ◽  
Claire Ménesguen ◽  
Xavier Carton ◽  
Sylvie Le Gentil ◽  
Richard Schopp
Keyword(s):  
Normal Mode ◽  
Growth Rates ◽  
Time Interval ◽  
Time Intervals ◽  
Horizontal Structure ◽  
Azimuthal Wave ◽  
Wave Numbers ◽  
Non Linear ◽  
Long Time ◽  
Short Time

The stability properties of a vortex lens are studied in the quasi geostrophic (QG) framework using the generalized stability theory. Optimal perturbations are obtained using a tangent linear QG model and its adjoint. Their fine-scale spatial structures are studied in details. Growth rates of optimal perturbations are shown to be extremely sensitive to the time interval of optimization: The most unstable perturbations are found for time intervals of about 3 days, while the growth rates continuously decrease towards the most unstable normal mode, which is reached after about 170 days. The horizontal structure of the optimal perturbations consists of an intense counter-shear spiralling. It is also extremely sensitive to time interval: for short time intervals, the optimal perturbations are made of a broad spectrum of high azimuthal wave numbers. As the time interval increases, only low azimuthal wave numbers are found. The vertical structures of optimal perturbations exhibit strong layering associated with high vertical wave numbers whatever the time interval. However, the latter parameter plays an important role in the width of the vertical spectrum of the perturbation: short time interval perturbations have a narrow vertical spectrum while long time interval perturbations show a broad range of vertical scales. Optimal perturbations were set as initial perturbations of the vortex lens in a fully non linear QG model. It appears that for short time intervals, the perturbations decay after an initial transient growth, while for longer time intervals, the optimal perturbation keeps on growing, quickly leading to a non-linear regime or exciting lower azimuthal modes, consistent with normal mode instability. Very long time intervals simply behave like the most unstable normal mode. The possible impact of optimal perturbations on layering is also discussed.

1787–1887–1987: reflections on a Sierra Leone bicentenary

Africa ◽  
1987 ◽  
Vol 57 (4) ◽  
pp. 411-421 ◽  
Author(s):  
Christopher Fyfe
Keyword(s):  
West Africa ◽  
Fifteenth Century ◽  
Sierra Leone ◽  
Forest Belt ◽  
Long Period ◽  
Language Pattern ◽  
Long Time ◽  
Opening Paragraph

Opening ParagraphSeen in the widest perspective, 1787 is only one date among the uncounted tens, perhaps hundreds, of thousands of years during which the present Sierra Leone has been inhabited. Archaeologists have done disappointingly little work there. But it is clear from their findings (and by implication from findings in the rest of forest-belt West Africa) that people have lived there a very long time. Though traditional historiography always tends to present the peoples of Sierra Leone as immigrants from somewhere else, the language pattern suggests continuous occupation over a very long period. As Paul Hair (1967) has shown, there has been a striking linguistic continuity in coastal West Africa since the fifteenth century. Nor is there evidence to suggest that before that period stability and continuity were not the norm.

scholarly journals Radiomorphology of the Habib Sealer-Induced Resection Plane during Long-Time Followup:A Longitudinal Single Center Experience after 64 Radiofrequency-AssistedLiver Resections

HPB Surgery ◽  
2010 ◽  
Vol 2010 ◽  
pp. 1-7 ◽  
Author(s):  
Robert Kleinert ◽  
Roger Wahba ◽  
Christoph Bangard ◽  
Klaus Prenzel ◽  
Arnulf H. Hölscher ◽  
...  
Keyword(s):  
Liver Resection ◽  
Morphological Characteristics ◽  
Postoperative Mortality ◽  
Coagulation Necrosis ◽  
Time Interval ◽  
Safe Alternative ◽  
Time Points ◽  
Single Center Experience ◽  
Long Time

Background. Radiofrequency (RF-) assisted liver resection devices like the Habib sealer induce a necrotic resection plane from which a small margin of necrotic liver tissue remains in situ. The aim of the present paper was to report our long-time experience with the new resection method and the morphological characteristics of the remaining necrotic resection plane. Methods. 64 RF-assisted liver resections were performed using the Habib sealer. Followup was assessed at defined time points. Results. The postoperative mortality was 3,6% and morbidity was 18%. The followup revealed that the necrotic zone was detectable in all analyzed CT and MRI images as a hypodense structure without any contrast enhancement at all time points, irrespectively of the time interval between resection and examination. Conclusion. Liver resection utilizing radiofrequency-induced resection plane coagulation is a safe alternative to the established resection techniques. The residual zone of coagulation necrosis remains basically unchanged during a followup of three years. This has to be kept in mind when evaluating the follow up imaging of these patients.

LONG‐TIME RESPONSE PREDICTED BY EXACT ELASTIC RAY THEORY

Geophysics ◽  
1965 ◽  
Vol 30 (3) ◽  
pp. 363-368 ◽  
Author(s):  
T. W. Spencer
Keyword(s):  
Formal Solution ◽  
Intermediate Stage ◽  
Time Limit ◽  
Time Interval ◽  
Individual Response ◽  
Axially Symmetric ◽  
Long Time ◽  
The Difference ◽  
The Individual ◽  
Significant Figures

The formal solution for an axially symmetric radiation field in a multilayered, elastic system can be expanded in an infinite series. Each term in the series is associated with a particular raypath. It is shown that in the long‐time limit the individual response functions produced by a step input in particle velocity are given by polynomials in odd powers of the time. For rays which suffer m reflections, the degree of the polynomials is 2m+1. The total response is obtained by summing all rays which contribute in a specified time interval. When the rays are selected indiscriminately, the difference between the magnitude of the partial sum at an intermediate stage of computation and the magnitude of the correct total sum may be greater than the number of significant figures carried by the computer. A prescription is stated for arranging the rays into groups. Each group response function varies linearly in the long‐time limit and goes to zero when convolved with a physically realizable source function.

scholarly journals First record of acari Arrenurus Dugès, 1834 as a parasite of Odonata species in Brazil

2013 ◽  
Vol 13 (4) ◽  
pp. 365-367 ◽  
Author(s):  
Marciel Elio Rodrigues ◽  
Cesar Carriço ◽  
Zeneida Teixeira Pinto ◽  
Paloma Martins Mendonça ◽  
Margareth Maria de Carvalho Queiroz
Keyword(s):  
Aquatic Insects ◽  
First Record ◽  
Water Mites ◽  
Freshwater Habitats

Water mites are common and widespread parasites of some aquatic insects in freshwater habitats. This is the first record of acari Arrenurus Dugès, 1834, as a parasite of Odonata in Brazil. Water mites were sampled from Miathyria marcella (Selys, 1857) and Ischnura fluviatilis (Selys, 1876).

Sign in / Sign up

Export Citation Format

Share Document