The expression of sexually dimorphic phenotypes from a shared genome between males and females is a longstanding puzzle in evolutionary biology. Increasingly, research has made use of transcriptomic technology to examine the molecular basis of sexual dimorphism through gene expression studies, but even this level of detail misses the metabolic processes that ultimately link gene expression with the whole organism phenotype. We use metabolic profiling in Drosophila melanogaster to complete this missing step, with a view to examining variation in male and female metabolic profiles, or metabolomes, throughout development. We show that the metabolome varies considerably throughout larval, pupal and adult stages. We also find significant sexual dimorphism in the metabolome, although only in pupae and adults, and the extent of dimorphism increases throughout development. We compare this to transcriptomic data from the same population and find that the general pattern of increasing sex differences throughout development is mirrored in RNA expression. We discuss our results in terms of the usefulness of metabolic profiling in linking genotype and phenotype to more fully understand the basis of sexually dimorphic phenotypes., Fiona C. Ingleby, Edward H. Morrow., and Obsahuje bibliografii
Sexually dimorphic features of adult males and females of Soricidex dimorphus, a species unparalleled in its dimorphism by any described representative of the family Demodecidae, are compared by scanning electron microscopy. The account of sexual dimorphism in S. dimorphus is preceded by a review of sexually dimorphic features in other demodecid genera. Minute constituents of general morphology of demodecid mites such as claws, solenidia and spines of legs or palps, dorsal podosomal tubercles, and integumental slits and pores, part of which are reported and/or shown in scanning electron micrographs for the first time, are also receiving detailed attention.
V naší studii se zabýváme zpěvní a hnízdní aktivitou ptáků v tropickém deštném lese Kamerunské hory v západní Africe. Ukázali jsme, že toto na první pohled stálé prostředí vykazuje výraznou sezonalitu v množství srážek ovlivňujících dostupnost potravy. Důsledkem je variabilní sezónní aktivita ptačího společenstva, zejména různých potravních guild. Sezonalita prostředí i ptačího společenstva se mění také s nadmořskou výškou., The aim of our study, conducted in the Republic of Cameroon (Africa), was to examine the singing and breeding activity of birds in a tropical rain forest. We have shown that this otherwise stable environment exhibits a distinct seasonality in rainfall, resulting in seasonal activity of bird communities, especially of various feeding guilds. Seasonality of environment and breeding of bird communities also changed with the altitude (tested on the Mount Cameroon - Mongo ma Ndemi)., Tereza Zenklová a kolektiv autorů., and Obsahuje bibliografii
Since 1998, a seismic network has been monitoring the underground gas storage located near the town of Příbram in the Central Bohemian Pluton, Czech Republic. Hundreds of weak induced seismic events have been recorded there. Moreover, several weak earthquakes have also been recorded from the vicinity of the nearby Orlík water reservoir. To improve location of both types of seismic events, shallow crustal structure of the region is studied in the present paper. Refraction measurements to distances of about 20 km were carried out using quarry blasts as seismic sources. Smoothed P-wave travel times were interpreted using the Wiechert-Herglotz method, which yielded a 1-D velocity model of shallow crustal structure down to a depth of about 1.7 km. The P-wave velocity of the model increases from about 5.0 km/s at the surface to about 6.15 km/s at the 1.7 km depth., Jiří Málek, Oldřich Novotný and Libor Žanda., and Obsahuje bibliografii
In this study shape optimization of fibers in composite fiber reinforced structure is presented. The problem targets the optimal shape with respect to the maximum bearing capacity and the minimum deformation of the whole composite set up. The shape is constrained by a constant volume (area) ratio. The optimization includes a process of seeking the overall properties of composites, i.e. localization and homogenization. Since no a priori estimate of the shape of fibers is known, numerical tool, finite element method, is employed. Such a problem is important in a wide range of applications, prevailingly in fiber reinforced concrete assessment, biomechanics, biophysics, and in the mechanics of classical composites with epoxy matrix. Since many types of fibers are used in various fiber reinforced concretes (fibers from polypropylene, steel, glass, clay, basalt, hemp, etc.), a deeper study is of importance to engineers and researchers. Application on FRC is preferred, i.e. fiber volume ratio is small, while classical composites require relatively very high volume ratio. The theory involves an original procedure leading to the optimal shape of fibers; it is then applied in the form of a numerical study. Also two examples from experiments verify the theoretical results. The problems are solved as two-dimensional, i.e. a unidirectional distribution of fibers is supposed., Petr P. Procházka and Martin Válek., and Obsahuje bibliografii
Rayleigh waves in the period range 0.2 - 3.0 s from eight quarry blasts are analyzed to obtain S-wave velocity model beneath the Příbram seven-station array in the Czech Republic. Locations and origin times of blasts are estimated using P- and S-wave onsets and then verified at the quarry in the vicinity of the location. This blind test confirms a sufficient precision of the location procedure for identification of quarries. Epicentral distances are in the range from 16 to 52 km. Group velocity dispersion curves of Rayleigh waves are determined by the frequency-time analysis. An average group velocity beneath the array for each period is computed with the help of mean travel-time curve for all blasts and stations. The resultant group velocity dispersion curve is inverted to obtain a 1-D S-wave velocity model using the Isometric method. The results are compared with known geological structure in the area of interest., Renata Gaždová, Petr Kolínský, Jiří Málek and Jan Vilhelm., and Obsahuje bibliografii
The steady-state photosynthetic irradiance and temperature responses of Viola hondoensis and V. keiskei (Violaceae) growing in proximity in their nati ve environment and under three levels of artificial shade of relative irradiance (RI) of 7, 20 and 50 % were investigated. The maximum photosynthetic rates and temperature optima under natural conditions were much higher in V. keiskei than in V. hondoensis, except when in leaves of V. keiskei chlorophyll was degraded due to autumn frosts. When grown under artificial shade, both species had higher temperature optima as RI decreased. Since leaves under the three RI conditions experienced a similar leaf temperature, it was concluded that the shifts in the temperature responses with RI resulted from acclimation to the varying irradiance. The higher temperature optima observed in V. keiskei under natural conditions were probably due to the fact that V. keiskei grew in more shady microhabitats than V. hondoensis.