Larvae of pyrrhocorid true bugs are not to spiders’ taste: putative Müllerian mimicry

Author(s):  
Jan Raška ◽  
Jan Krajíček ◽  
Zuzana Bosáková ◽  
Pavel Štys ◽  
Alice Exnerová

Abstract Adults and larvae of a true bug, Scantius aegyptius (Heteroptera: Pyrrhocoridae), closely resemble sympatric firebugs, Pyrrhocoris apterus, and probably form a mimetic relationship with the latter species. Scantius aegyptius adults, although producing a secretion atypical of true bugs, are to some extent chemically protected against predators. In this study, we analysed the composition and function of the larval secretion in S. aegyptius, and investigated the mimetic relationship between larvae of S. aegyptius and P. apterus. The main component of the larval secretion in S. aegyptius is 2-heptanol, a chemical not known to function in anti-predatory defence, followed by (E)-2-octenal, a common defensive chemical of true bugs. When larvae of both species were presented to jumping spiders (Evarcha arcuata), S. aegyptius was slightly less well protected than P. apterus, but the spiders behaved towards the two species in a similar way: they quickly learned to avoid the bugs, but usually attacked them again on the second day. The spiders also generalized their learned avoidance from one true bug species to the other (with only slight asymmetry favouring S. aegyptius), suggesting that the bugs’ mimetic relationship is most probably Müllerian, being advantageous to both species.

1985 ◽  
Vol 54 (04) ◽  
pp. 739-743 ◽  
Author(s):  
Federica Delaini ◽  
Elisabetta Dejana ◽  
Ine Reyers ◽  
Elisa Vicenzi ◽  
Germana De Bellis Vitti ◽  
...  

SummaryWe have investigated the relevance of some laboratory tests of platelet function in predicting conditions of thrombotic tendency. For this purpose, we studied platelet survival, platelet aggregation in response to different stimuli, TxB2 and 6-keto-PGFlα production in serum of rats bearing a nephrotic syndrome induced by adriamycin. These animals show a heavy predisposition to the development of both arterial and venous thrombosis. The mean survival time was normal in nephrotic rats in comparison to controls. As to aggregation tests, a lower aggregating response was found in ADR-treated rats using ADP or collagen as stimulating agents. With arachidonic acid (AA) we observed similar aggregating responses at lower A A concentrations, whereas at higher AA concentrations a significantly lower response was found in nephrotic rats, despite their higher TxB2 production. Also TxB2 and 6-keto-PGFlα levels in serum of nephrotic rats were significantly higher than in controls. No consistent differences were found in PGI2-activity generated by vessels of control or nephrotic rats.These data show that platelet function may appear normal or even impaired in rats with a markedly increased thrombotic tendency. On the other hand, the significance of high TxB2 levels in connection with mechanisms leading to thrombus formation remains a controversial issue.


Geosciences ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 120
Author(s):  
Teresa Brzezińska-Wójcik

The Polish part of the Roztocze Transboundary Biosphere Reserve area is characterized by diversified geotourism resources with relatively high value. However, their potential seems not to be fully used in the current product offer. The aim of the study was therefore to assess the spatial variability of the geotourism potential and function and to determine their interrelations in view of further development of geotourism in the Roztocze TBR and the perspective of creation of the “Kamienny Las na Roztoczu” geopark. The study was carried out with the use of the taxonomic method of multidimensional comparative analysis consisting of calculation and analysis of general, total, and partial indices of the geotourism potential and function in 22 communes. The results showed the highest total indicator of geotourism potential in two communes, i.e. Józefów and Krasnobród, and the highest value of the total geotourism function index in Krasnobród. The results of the analysis of the relationships between the geotourism potential and function indicate that the geotourism resources and products are fully used in terms of the development of the function only in Krasnobród commune. In turn, the value of the total geotourism function index in the Zwierzyniec commune exceeds the geotourism potential indicator, which implies that this area is overloaded by tourist movement. The total indicators of geotourism potential in the other communes, especially Józefów, Krasnobród, Lubycza Królewska, and Susiec, indicate the possibility of more intensive exploitation of geotourism resources in preparation of interesting products in compliance with the principles of sustainable development and, consequently, the development of the geotourism function.


Author(s):  
Jung-Hoon Cho ◽  
Seung Woo Ham ◽  
Dong-Kyu Kim

With the growth of the bike-sharing system, the problem of demand forecasting has become important to the bike-sharing system. This study aims to develop a novel prediction model that enhances the accuracy of the peak hourly demand. A spatiotemporal graph convolutional network (STGCN) is constructed to consider both the spatial and temporal features. One of the model’s essential steps is determining the main component of the adjacency matrix and the node feature matrix. To achieve this, 131 days of data from the bike-sharing system in Seoul are used and experiments conducted on the models with various adjacency matrices and node feature matrices, including public transit usage. The results indicate that the STGCN models reflecting the previous demand pattern to the adjacency matrix show outstanding performance in predicting demand compared with the other models. The results also show that the model that includes bus boarding and alighting records is more accurate than the model that contains subway records, inferring that buses have a greater connection to bike-sharing than the subway. The proposed STGCN with public transit data contributes to the alleviation of unmet demand by enhancing the accuracy in predicting peak demand.


Evolution ◽  
1977 ◽  
Vol 31 (2) ◽  
pp. 452-453
Author(s):  
P. M. Sheppard ◽  
J. R. G. Turner

2016 ◽  
Vol 14 (1) ◽  
pp. nrs.14002 ◽  
Author(s):  
Shailaja D. Divekar ◽  
Deanna M. Tiek ◽  
Aileen Fernandez ◽  
Rebecca B. Riggins

Estrogen-related receptors (ERRs) are founding members of the orphan nuclear receptor (ONR) subgroup of the nuclear receptor superfamily. Twenty-seven years of study have yet to identify cognate ligands for the ERRs, though they have firmly placed ERRα (ESRRA) and ERRγ (ESRRG) at the intersection of cellular metabolism and oncogenesis. The pace of discovery for novel functions of ERRβ (ESRRB), however, has until recently been somewhat slower than that of its family members. ERRβ has also been largely ignored in summaries and perspectives of the ONR literature. Here, we provide an overview of established and emerging knowledge of ERRβ in mouse, man, and other species, highlighting unique aspects of ERRβ biology that set it apart from the other two estrogen-related receptors, with a focus on the impact of alternative splicing on the structure and function of this receptor.


1999 ◽  
Vol 146 (2) ◽  
pp. 333-344 ◽  
Author(s):  
Chavela M. Carr ◽  
Eric Grote ◽  
Mary Munson ◽  
Frederick M. Hughson ◽  
Peter J. Novick

Proteins of the Sec1 family have been shown to interact with target-membrane t-SNAREs that are homologous to the neuronal protein syntaxin. We demonstrate that yeast Sec1p coprecipitates not only the syntaxin homologue Ssop, but also the other two exocytic SNAREs (Sec9p and Sncp) in amounts and in proportions characteristic of SNARE complexes in yeast lysates. The interaction between Sec1p and Ssop is limited by the abundance of SNARE complexes present in sec mutants that are defective in either SNARE complex assembly or disassembly. Furthermore, the localization of green fluorescent protein (GFP)-tagged Sec1p coincides with sites of vesicle docking and fusion where SNARE complexes are believed to assemble and function. The proposal that SNARE complexes act as receptors for Sec1p is supported by the mislocalization of GFP-Sec1p in a mutant defective for SNARE complex assembly and by the robust localization of GFP-Sec1p in a mutant that fails to disassemble SNARE complexes. The results presented here place yeast Sec1p at the core of the exocytic fusion machinery, bound to SNARE complexes and localized to sites of secretion.


2017 ◽  
Vol 8 (1) ◽  
pp. 178-200
Author(s):  
Zaprulkhan Zaprulkhan

This article discusses Bediuzzaman Said Nursi’s ideas on significance of the Practices of the Prophet (Sunna) for modern people. In the present day, many modern people deal with some problems such as spiritual crisis (existential vacuum), moral degradation, and so on. On the other hand, according to Said Nursi, Practices of the Prophet are all highly beneficial remedies for sicknesses of the spirit, mind, and heart, and particularly for social sicknesses. Accordingly, Practices of the Prophet could give the best solution for modern people problems, both individual sicknesses and social sicknesses. Before proposing Said Nursi’s perspective about significance of sunna, the paper forwards epistemological questions: How are the meaning and function of sunna according to Said Nursi? How are the urgent problems of modern people? What is the significance of Practices of the Prophet for modern people in the view of Said Nursi? The answer of these questions will determine the significance of the Practices of the Prophet in our era and in the future.


Diacronia ◽  
2015 ◽  
Author(s):  
Francisc Gafton

Natural entities—plants and animals, on the one hand, society, language, and culture, on the other—emerge through an assiduous diachronic effort, respond to diachronically developed needs, exist and function diachronically. However, through the instruments at his disposal, man can only perceive and grasp the “fragment”, seizing it for a prolonged instant, which explains his objective tendency to segment the spatiotemporal reality according to his own proportions and abilities. Reality itself, however, cannot be subjected to the unnatural segregation of one of its own products and elements, and cannot be fully comprehended in any other way than how it exists: as a whole. At the end of the synchronic road, what offers comprehension and understanding of the ontologically-becoming whole is the path of the diachronic method.


2020 ◽  
Vol 202 ◽  
pp. 07073
Author(s):  
Yuliani Rahmah

Omamori is known as an important part of religious life in Japanese society. Omamori, which has been known since the Tokugawa era and still survives in modern Japanese society, is often known as part of the collective culture of Japanese society. However, behind its function as a spiritual medium, Omamori holds a meaning of harmony between humans and nature. With the library research, this article aims to explain the other meanings contained in an Omamori. It is in line with the teachings of Shinto whose concept is centered on nature and the environment. The form, type, and function of an Omamori also symbolize the meaning of harmony between humans and their environment that gives birth to attitudes that support the preservation of the natural environment.


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