Deposition, removal and production site of the amorphous mating plug in the spider Philodromus cespitum

2018 ◽  
Vol 105 (7-8) ◽  
Author(s):  
Lenka Sentenská ◽  
Stano Pekár ◽  
Gabriele Uhl
Keyword(s):  
2020 ◽  
Vol 22 ◽  
Author(s):  
Shannon L Summers ◽  
Akito Y Kawahara ◽  
Ana P. S. Carvalho

Male mating plugs have been used in many species to prevent female re-mating and sperm competition. One of the most extreme examples of a mating plug is the sphragis, which is a large, complex and externalized plug found only in butterflies. This structure is found in many species in the genus Acraea (Nymphalidae) and provides an opportunity for investigation of the effects of the sphragis on the morphology of the genitalia, which is poorly understood. This study aims to understand morphological interspecific variation in the genitalia of Acraea butterflies. Using specimens from museum collections, abdomen dissections were conducted on 19 species of Acraea: 9 sphragis bearing and 10 non-sphragis bearing species. Genitalia imaging was performed for easier comparison and analysis and measurements of genitalia structures was done using ImageJ software. Some distinguishing morphological features in the females were found. The most obvious difference is the larger and more externalized copulatory opening in sphragis bearing species, with varying degrees of external projections. Females of the sphragis bearing species also tend to have a shorter ductus (the structure that connects the copulatory opening with the sperm storage organ) than those without the sphragis. These differences may be due to a sexually antagonistic coevolution between the males and females, where the females evolve larger and more difficult to plug copulatory openings and the males attempt to prevent re-mating with the sphragis.


2020 ◽  
pp. 10-21 ◽  
Author(s):  
Vladimir V. Voronov ◽  
Nikolay I. Shchepetkov

The article describes content of original and relevant but virtually forgotten thesis of V.V. Voronov on lighting of production site interiors by means of overhead natural (using three types of skylights) and artificial illumination, in order to elaborate scientific methodology for architectural design of more qualitative luminous environment on the basis of comprehensive approach and enhanced criteria framework of its evaluation using light engineering parameters. The thesis is unique in terms of the scope and quality of field and laboratory observations which are reflected not only in the text but also in the graphical attachments, namely photos, figures, schemes, drawings, charts, nomograms, and diagrams accompanied by specific measured or calculated parameters. The first part of the thesis contains theoretical basics and results of field observations conducted by different methods. This second part is the exposition of chapter 3 of the V.V. Voronov’s candidate thesis (1985). It describes the methodology for and the results of the experiments by means of planar and volumetric light simulation using the architectural lighting simulating assembly (chamber) which were conducted in MARKHI in 1970–1985.


Author(s):  
A.F. Khasanova ◽  
◽  
M.A. Gallyamov ◽  
Z.A. Zakirova ◽  
◽  
...  

Author(s):  
Kamila Gieba

The article examines ways of representing nuclear catastrophe in Kate Brown's Plutopia: Nuclear Families, Atomic Cities, and the Great Soviet and American Plutonium Disasters. In 1957 an explosion in the Mayak works - a plutonium production site - led to massive contamination of the surrounding areas. The event remained a closely kept secret till 1992, absent from the public sphere and cultural texts, despite the fact that the scale of contamination was as big as the Chernobyl explosion. One of the reasons for this was the difficulty of representing nuclear radiation. The author focuses on three contexts of this impossibility: in relation to the cognitive theory of the metaphor, the figure of the sick body as bearer of memory, and the invisibility of the nuclear landscape.


2020 ◽  
Vol 85 (2) ◽  
pp. 279-304
Author(s):  
Timothy D. Everhart ◽  
Bret J. Ruby

This article offers insights into the organization of Scioto Hopewell craft production and examines the implications of this organization through the lens of ritual economy. We present a novel analysis of investigations at the North 40 site, concluding that it is a craft production site located on the outskirts of the renowned Mound City Group. High-resolution landscape-scale magnetic survey revealed a cluster of three large structures and two rows of associated pits; one of the buildings and three of the pits were sampled in excavations. Evidence from the North 40 site marks this as the best-documented Scioto Hopewell craft production site. Mica, chert, and copper were crafted here in contexts organized outside the realm of domestic household production and consumption. Other material remains from the site suggest that crafting was specialized and embedded in ceremonial contexts. This analysis of the complex organization of Scioto Hopewell craft production provides grounds for further understanding the elaborate ceremonialism practiced by Middle Woodland (AD 1–400) societies and adds to the known complexity of craft production in small-scale societies. Furthermore, this article contributes to a growing body of literature demonstrating the utility of ritual economy as a framework for approaching the sociality of small-scale societies.


2021 ◽  
Vol 11 (11) ◽  
pp. 5092
Author(s):  
Bingyu Liu ◽  
Dingsen Zhang ◽  
Xianwen Gao

Ore blending is an essential part of daily work in the concentrator. Qualified ore dressing products can make the ore dressing more smoothly. The existing ore blending modeling usually only considers the quality of ore blending products and ignores the effect of ore blending on ore dressing. This research proposes an ore blending modeling method based on the quality of the beneficiation concentrate. The relationship between the properties of ore blending products and the total concentrate recovery is fitted by the ABC-BP neural network algorithm, taken as the optimization goal to guarantee the quality of ore dressing products at the source. The ore blending system was developed and operated stably on the production site. The industrial test and actual production results have proved the effectiveness and reliability of this method.


2017 ◽  
Vol 246 ◽  
pp. 241-255 ◽  
Author(s):  
Pauline Buysse ◽  
Bernard Bodson ◽  
Alain Debacq ◽  
Anne De Ligne ◽  
Bernard Heinesch ◽  
...  

1978 ◽  
Vol 65 (10) ◽  
pp. 543-545 ◽  
Author(s):  
H. Z. Levinson ◽  
A. R. Levinson ◽  
T. -I. Jen ◽  
J. L. D. Williams ◽  
G. Kahn ◽  
...  

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