Insects produce pigment and structural colours mainly for camouflage, signaling, physical protection or temperature regulation, and colour patterns can provide information about individual quality. Although the evolutionary function and nature of the variability in colouration are well known for many invertebrate taxa, there is little information on this topic for ants. We studied individual variation in the melanin-based colour traits of workers of the red wood ant, Formica rufa (Hymenoptera: Formicidae), from 20 colonies in Southern Finland and revealed the type of colouration in this species. First, using the threshold approach we distinguished between continuous and discrete variations. Furthermore, the analyses affirmed nine discrete morphs in terms of the colouration on the head and eight on the pronotum, while only continuous variation were found on the other body parts. Measuring the size of a particular colour pattern, the intensity of colour expression (degree of melanization) and statistical analyses allowed an assessment of the intra-individual variation in both discrete and continuous patterns. The results revealed substantial modularity in the above mentioned colouration traits. In workers of F. rufa there were individuals with a dark head and light coloured thorax and vice a versa. Size of the dark pigment colour patterns exhibited less modularity than the degree of melanization. Finally, the interrelation between colouration traits and individual body size revealed their size-dependent origin. Small individuals had relatively larger areas of colour on the head and thorax than big individuals. These results are likely to facilitate further taxonomical and ecological studies on red wood ants, as they show it is possible to assess colouration traits in ants. However, more studies are needed on the function of polymorphism and modular colouration in this group of ants., Oksana Skaldina, Jouni Sorvari., and Obsahuje bibliografii
Cardiac fibroblast-myofibroblast transformation (CMT) is a critical event in the initiation of myocardial fibrosis. Notch signaling has been shown to regulate myofibroblast transformation from other kinds of cells. However, whether Notch signaling is also involved in CMT remains unclear. In the present study, expressions of Notch receptors in cardiac fibroblasts (CFs) were examined, effects of Notch signaling inhibi tor N-[N-(3,5-difluorophenacetyl)- l-alanyl]-S-phenylglycine t-butyl ester (DAPT) and transforming growth factor-β1 (TGF-β1) on CMT were determined by increasing alpha-smooth muscle actin (α-SMA) expression and collagen synthesis, and Notch signaling was examined by analyzing expressions of Notch receptors. The results showed that: (1) Notch receptor 1, 2, 3 and 4 were all expressed in CFs; (2) DAPT promoted CMT in a time -dependent manner; (3) During the period of CMT induced by TGF-β1, expressions of Notch receptor 1, 3 and 4 in CFs were down-regulated, whereas there was no change for Notch receptor 2. Moreover, the downtrends of Notch 1, 3 and 4 were corresponding to the trend growth of α-SMA expression and collagen synthesis. These results suggested that inhibiting of Notch signaling might promote CMT. The down-regulations of Notch receptor 1, 3 and 4 induced by TGF-β1 may facilitate CMT. In conclusion, inhibition of Notch signaling might be a novel mech anism of CMT in myocardial fibrosis., Y.-H. Fan ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
In this note, we point out that Theorem 3.1 as well as Theorem 3.5 in G. D. Çaylı and F. Karaçal (Kybernetika 53 (2017), 394-417) contains a superfluous condition. We have also generalized them by using closure (interior, resp.) operators.
Six mite species of the family Myobiidae, Radfordia (Auslromyobia) persica sp. п., Radfordia (Austromyobia) merioni Bochkov, Dubinina et Chirov, 1990, Radfordia (Radfordia) acomys Fain ct Lukoschus, 1977, Radfordia (Radfordia) affinis (Poppe, 1896), Radfordia (Graphiurobia) dyromys Fain et Lukoschus, 1973, and Myobia (Myobia) murismusculi (Schrank, 1781) were found in Iran on the rodents Gerbillus cheesmani Thomas, Meriones libycus Lichtenstein, Acomys cahirinus (Desmarest), Mus musculus L., Dryomys nitedula (Pallas), and Mus musculus, respectively. R. (A.) persica is described as a new species from the female, male and tritonymph. The other five myobiid species arc new to Iran.
The occurrence of common gudgeon in the River Morača drainage of southern Montenegro was investigated. Low numbers of specimens were recorded in four out of five localities investigated on the Zeta River and at a single locality on the lower part of the River Morača. Allozyme analysis revealed that the specimens examined belong to the species Gobio gobio (Linnaeus, 1758). The lower number of lateral line scales in common gudgeon from the Ohrid-Drim-Skadar system, as compared with other European populations, probably indicates clinal variability. The results also demonstrate that the subspecies Gobio gobio ohridanus Karaman, 1924 is not a valid taxon.
Two myxosporean species, Zschokkella pleomorpha Lom et Dyková, 1995 (Zp) and Ortholinea fluviatilis Lom et Dyková, 1995 (Of) from the kidney of Tetraodon fluviatilis were studied by transmission electron microscope. Coelozoic sporogonie plasmodia of both species use pseudopodia-like projections for attachment to the epithelial cells of renal tubules. These projections either attach to host microvilli forming an interface reminiscent of septate junction (Zp) or are embedded into the epithelial cell surface (Of) or are inserted into gaps between epithelial cells (Zp, Of). Zp produces spores only by direct division of generative cells while in Of pansporoblasts prevail over direct division of generative cells. Sporogonie plasmodia of Zp greatly differ in size and in the variety of cytoplasmic constituents. A special feature in capsulogenesis is a transient envelope encasing the capsular primordium; there are fine fibres on the surface of the nascent filament spaced at 11 nm. In Of, vegetative nuclei of the plasmodium adhere to generative cells in a way reminding of sporoplasmic plasmodium of actinospores. In Of plasmodia, several unusual cytoplasmic structures were observed (membrane bound bodies with fuzzy radial contents or with a central dense inclusion, and endoplasmic reticulum cistemae forming a scalloped network). Of may also form intracellular coelozoic sporogonie plasmodia in the epithelial cells of renal tubules; these stages do not seem to constitute an important part of the life cycle.