V rámci záchranného výzkumu polykulturního sídliště na hranici katastrů Úhřetice a Tuněchody byly prozkoumány zahloubené části dvou pyrotechnologických objektů z doby římské. Cílem článku je rekonstrukce stavebních postupů, podoby a funkce těchto zařízení za využití mezioborového přístupu zahrnujícího analýzu petrografickou, sedimentologickou, mineralogickou, geochemickou, xylotomární, analýzu makrozbytků rostlin a otisků rostlin. Analýzou popelovité vrstvy z výplně objektů byly identifikovány úlomky sparitického karbonátu, který je dokladem využití pecí pro pálení vápna. Analýza mazanice umožnila vytvořit testovatelné hypotézy o konstrukci zařízení a aplikovaných technologických postupech. and The sunken parts of two pyrotechnological features from the Roman period were studied during rescue excavations of a polycultural settlement. The aim of the article is to reconstruct the construction procedures, and the form and function of these facilities by means of a multidisciplinary approach employing petrographic, sedimentological, mineralogical, geochemical analyses, xylotomy, and by the analysis of plant macro-remnants and plant imprints. Fragments of sparitic carbonate, evidence of the use of the kilns for the firing of lime, were identified through the analysis of the ashy layers from the fill of the feature. The analysis of the daub enabled the formulation of a testable hypothesis on the construction of the kiln and the applied technological procedures.
The grasshopper Dichroplus pratensis Bruner is polymorphic and polytypic for a complex Robertsonian system. In this species, centric fusions induce changes in number and position of chiasmata, and thus potentially affect intrachromosomal genetic recombination and genetic variability. Males and females, from 23 populations covering most of the geographic range of the species and spanning 22 degrees of latitude, were studied. We analyzed chiasma frequency in relation to variability in six exomorphological characters. The chromosomal polymorphisms of D. pratensis are widely geographically distributed, and show a central-marginal pattern, in which the central populations (those occupying the ecologically optimal habitats) have high mean frequencies of different fusions per individual (F) of up to F = 3.00 and total chiasma frequencies as low as XT = 8.98 per cell, while those near the margins of the distribution (central Patagonia and the Andes) have very low levels of chromosomal polymorphisms [down to F = 0.00 in most geographically marginal locations), monomorphic karyotypes and high chiasma frequencies (XT = 11.66, in the southernmost (Rada Tilly, 45°57´S) and XT = 12.01 in the northernmost population (Volcán, 23°55´S)]. Increasing chiasma frequencies towards the margins of the range are positively and significantly correlated with increasing levels of morphological variability. The decrease in fusion polymorphism and the consequent increase in genetic recombination (both inter- and intrachromosomal) in the marginal areas, is a result of natural selection favouring higher levels of variability, which could be adaptive in ecologically harsher and changing environments.
Cliromospheric activity is found in ten types of stars, both single and binary. Variability at many time scales is reviewed, from minutes to centuries. The emphasis is on what is not understood, incorrecty understood, and understood but not appreciated. Observational results in hand include photometry, spectroscopy, spectrophotometry, speckle interferometry, magnetic flelds, and orbltal period variations. Certain physical mechanisms responsible for variability are discussed, making the distinction between the well-established, tlie suspected, and the posslble. Specific topics
include flares, rotation, differential rotation, synchronization, circularization, starspots, spot models, migratlon periods, spot cycles, magnetic activity cycles, sector structure, Maunder minima,
pulsation, light curve solutions, convective envelope changes, mass transfer, mass loss, and orbital period variations. Specific directions for future research are identified.
The article aims at identifying the origin of voids left by burnt-out organic material within the ceramic paste of Neolithic pottery from the Czech Republic territory. In methodological terms, an experimental reference collection was created and compared with the original early Neolithic pottery from the sites of Bylany by Kutná Hora and Těšetice-Kyjovice. The key analytical procedure consisted in non-destructive 3D microtomography (uCT) analysis, which is especially well suited for the study of the internal spatial organization of voids and temper. It allows to determine whether it is possible to define different manufacturing techniques employed for vessel construction on the basis of internal distribution of voids. The research identified cow dung as the probable organic temper within the original LBK ceramic paste. The ‘S’-forming technique, consisting in pressing the coil to the vessel wall, most closely corresponded to features observed at the Neolithic vessels. and Cílem článku je identifikování původu porozit, tj. stop po vyhořelé organické příměsi uvnitř hrnčířské hmoty, u neolitické keramiky (LBK) z území České republiky. Metodicky je práce založena na srovnání experimentálně zhotovených vzorků s originální keramikou staršího neolitu z lokalit Bylany u Kutné Hory a Těšetice-Kyjovice. Klíčovým analytickým postupem byla nedestruktivní 3D mikrotomografická analýza (uCT), která je přínosná právě pro studium vnitřní prostorové organizace porozit a příměsí. Umožňuje tak zkoumat, jestli je možné na základě vnitřního uspořádání pórů definovat odlišné výrobní techniky použité pro stavbu nádob. Výsledkem výzkumu bylo identifikování kravského hnoje jako pravděpodobné organické příměsi v keramické hmotě původní LBK. Jako utvářecí výrobní postup, který nejblíže odpovídal znakům pozorovaným na neolitických nádobách, byla určena tzv. technika „S“, založená na přimačkávání válečku ke stěně nádoby.
The aim of this study was to obtain information on the karyotypes, testes and ovaries of three fulgoroid families, mainly in the Issidae but also in the Caliscelidae and Acanaloniidae. For the Issidae, the data is for 19 species belonging to 11 genera of the subtribes Issina (2 species, 1 genus), Hysteropterina (14 species, 9 genera) and Agalmatiina (3 species, 2 genera) of the tribe Issini. The male karyotypes are shown to be quite uniform across the tribe, with 2n = 26 + X in all species studied except Latilica maculipes (Melichar, 1906) with 2n = 24 + X. The modal karyotype, 2n = 26 + X, matches the most probable ancestral state in the Fulgoroidea. In the majority of cases the number of seminal follicles in males and ovarioles in females are stable within but fairly variable among the species, the modal value of the follicle number is 10 per testis. Contrary to what might be expected from other fulgoroid families, such as the Dictyopharidae and Delphacidae, the variability in these characters revealed neither regular trends nor evident correspondence with the taxonomy of Issidae. In the Caliscelidae, all species studied had testes consisting of 6 follicles each and karyotypes of 2n = 24 + X and 26 + XY, respectively, in 3 and 1 species. The only representative studied of the Acanaloniidae, Acanalonia bivittata (Say, 1825), had 2n = 24 + X and 13 follicles in its testis. The variability in all the characters investigated is discussed and compared to other fulgoroid families, primarily to the most extensively studied families, Delphacidae and Dictyopharidae.
Results are presented from a study of variability in the stellar wind of G8 Cygni [07.5 III((f))], based on 33 lUE high resolution spectra taken over ~ 7 days. Significant changes are evident in the Si IV resonance line profiles on timescales as short as ~ 1 hour, cliaracterised by broad absorption enhancements at relatively low velocity (0.5 to 0.7 of the terminal velocity, υ∞) which evolve into high velocity discrete absorption components (at > 0.8 over a period of ~ 1 day. The recurrence timescale for the appearance of the broad features is ~ 15-20 hours. Three well monitored consecutive sequenccs of progressive opacity enhancements are described. Their properties are parameterised and incorporated into a self-consistent phenomenological model where the opacity enhancements and ‘underlying’ wind sure radiatively coupled.
The model results show that the absorption enhancements do not propagate from the photosphere in any simple way, and are not due to spherically symmetric phenomena. We conclude that the discrete absorption variability in G8 Cyg is not due to ‘shells’ or ‘puffs’ of matter, but instcaid arise from material passing through perturbations in the flow, which may be illustrated in terms of spirally wound-up streams.
Ample experimental evidence suggests that sepsis could interfere
with any mitochondrial function; however, the true role of
mitochondrial dysfunction in the pathogenesis of sepsis-induced
multiple organ dysfunction is still a matter of controversy. This
review is primarily focused on mitochondrial oxygen consumption
in various animal models of sepsis in relation to human disease
and potential sources of variability in experimental results
documenting decrease, increase or no change in mitochondrial
respiration in various organs and species. To date, at least three
possible explanations of sepsis-associated dysfunction of the
mitochondrial respiratory system and consequently impaired
energy production have been suggested: 1. Mitochondrial
dysfunction is secondary to tissue hypoxia. 2. Mitochondria are
challenged by various toxins or mediators of inflammation that
impair oxygen utilization (cytopathic hypoxia). 3. Compromised
mitochondrial respiration could be an active measure of survival
strategy resembling stunning or hibernation. To reveal the true
role of mitochondria in sepsis, sources of variability of
experimental results based on animal species, models of sepsis,
organs studied, or analytical approaches should be identified and
minimized by the use of appropriate experimental models
resembling human sepsis, wider use of larger animal species in
preclinical studies, more detailed mapping of interspecies
differences and organ-specific features of oxygen utilization in
addition to use of complex and standardized protocols evaluating
mitochondrial respiration.
Diabetes mellitus 2 (DM2) is the seventh cause of death worldwide. One of the reasons is late diagnosis of vascular damage. Pulse wave velocity (PWV) has become an independent marker of arterial stiffness and cardiovascular risk. Moreover, the previous studies have shown the importance of beat-to-beat PWV measurement due to its variability among the heart cycle. However, variability of PWV (PWVv) of the whole body hasn't been examined yet. We have studied a group of DM II and heathy volunteers, to investigate the beat-to-beat mean PWV (PWVm) and PWVv in the different body positions. PWV of left lower and upper extremities were measured in DM2 (7 m/8 f, age 68±10 years, BP 158/90±19/9 mm Hg) and healthy controls (5 m/6 f, age 23±2 years, BP 117/76±9/5 mm Hg). Volunteers were lying in the resting position and of head-up-tilt in 45° (HUT) for 6 min. PWVv was evaluated as a mean power spectrum in the frequency bands LF and HF (0.04-0.15 Hz, 0.15-0.5 Hz). Resting PWVm of upper extremity was higher in DM2. HUT increased lower extremity PWVm only in DM2. Extremities PWVm ratio was significantly lower in DM2 during HUT compared to controls. LF and HF PWVv had the same response to HUT. Resting PWVv was higher in DM2. Lower extremity PWVv increased during HUT in both groups. PWVm and PWVv in DM2 differed between extremities and were significantly influenced by postural changes due to hydrostatic pressure. Increased resting PWVm and PWVv in DM2 is a marker of increased arterial stiffness.
The distribution, variability and host specificity of species of Babesia Starcovici, 1893 were studied in questing ticks collected on the northwestern edge of the Pannonian Basin in the south-easternmost part of the Czech Republic and in western Slovakia. The area is characterised by relatively natural floodplain habitats and the sympatric occurrence of three tick species possessing wide host spectra, namely Ixodes ricinus (Linnaeus), Dermacentor reticulatus (Fabricius) and Haemaphysalis concinna Koch. Analysis was carried out on 1,408 I. ricinus, 2,999 D. reticulatus and 150 H. concinna altogether, collected from 59 localities. We documented the presence of Babesia spp. not only in I. ricinus but also in H. concinna in the Czech Republic. Two isolates from I. ricinus were classified as B. venatorum Herwaldt, Cacciò, Gherlinzoni, Aspöck, Slemenda, Piccaluga, Martinelli, Edelhofer, Hollenstein, Poletti, Pampiglione, Löschenberger, Tura et Pieniazek, 2003 (formerly determined as Babesia sp. EU1), which is a zoonotic parasite and can cause human babesiosis. The rest of our amplicons were very similar to B. canis (Piana et Galli-Valerio, 1895), which is usually transmitted by D. reticulatus. Despite the huge amount of examined samples, all D. reticulatus ticks were Babesia-free. Due to this finding, we did not consider our obtained isolates to be B. canis, but other closely related species possessing a similar sequence of the studied portion of 18S rDNA. Although this genetic marker is most frequently used in PCR-based diagnostic methods of babesias, its low variability compromises its reliability in studies based only on this marker., Markéta Rybářová, Michaela Honsová, Ivo Papoušek, Pavel Široký., and Obsahuje bibliografii