Tides and Arp's hypothesis about distribution of Hii regions

We discuss Arp's hypothesis that the HII regions are more numerous and more conspicuous on the side of a galaxy facing its companion. Arp's hypothesis seems not to be true if we add to Hodge's sets of galaxies only the most probably tidally-interacting cases.     

Relativistic hierarchical cosmology

In this paper we discuss a hierarchical model of Universe which was proposed by Wesson (1975). We assert that the mathematical formalism used by Wesson leads to contradiction with Einstein's equations.     

Laboratory studies for beam plasma discharge experiments with rockets

Laboratory results of beam plasma discharge (BPD) (dimensions several metres) in a homogeneous atmosphere and a jet of neutral gas are presented. The beam was obtained by an electron gun of the same type as used in rocket experiments.The BPD parameters glow intensity, electromagnetic field and its spectrum, electron density as well as the flux of scattered electrons were measured. In addition, photographs of the BPD were taken. The threshold of BPD ignition was determined as a function of gas pressure and beam parameters. The initial stage of BPD formation as well as various types of oscillatory processes in the discharge were studied. A possible process of BPD initiation is presented.     

Abnormal features of Macoma balthica (Bivalvia) in the Baltic Sea: alerting symptoms of environmental adversity?

Recent studies of the Baltic clam Macoma balthica (L.) from the southern Baltic (the Gulf of Gdansk) have revealed striking morphological, histological and cytogenetic features. Strong deformation of the shell, including elongation of the posterior end and the appearance of an easily visible flexure in this part, has been recorded. The population contribution of the deformed blunt shelled ("irregular") clams ranged from 0% to 65% and tended to increase with depth. The morphologically "irregular" clams had higher accumulated tissue concentrations of trace metals (As, Ag, Cd, Pb, Cu and Zn), indicating a different metal handling ability. Adverse conditions in deeper water regions of the Gulf (e.g. hypoxia, hydrogen sulphide, elevated bioavailability of contaminants) have been suggested as inducers of the phenotypical changes (morphological deformation) in part of the population and, in parallel, of the specific physiological adaptations that result in higher metal accumulation in the "irregular" clams. Cytogenetic and histological analyses showed the presence of tumours in gill cells and digestive system of the affected clams, the prevalence of disseminated neoplasia ranging from 0% to 94% depending on the site. The disease was manifested by a modified karyotype (i.e. an abnormal number and morphology of chromosomes), a higher activity of nucleolar organizer regions (AgNORs), and tissue lesions (enlarged cells, actively proliferative with pleomorphic nuclei). Bottom sediments showed acute toxicity and have been proposed as a source of an initialising carcinogenic factor. However, none of the ecotoxicological studies provided was successful in the clear demonstration of a single (or multifactorial) agent that can account for the disseminated neoplasia.     

The eastern continuation of the Cadomian orogen: U–Pb zircon evidence from Saxo-Thuringian granitoids in south-western Poland and the northern Czech Republic

We report U–Pb single zircon ages from three pre-Variscan granitoids in the NE part of the Bohemian Massif. The Platerówka granodiorite from the Lausitz-Izera Unit, the Polish Sudetes, has been dated at 533±9 Ma. The Bitouchov granite form the SW part of the South Krkonoe Unit, the Czech Sudetes, gave an age of 540+11/–10 Ma, and the Wdroe granodiorite in the Fore-Sudetic Block yielded 548±9 Ma. All these latest Vendian/Early Cambrian granitoids represent the post-tectonic expression of a late Proterozoic Cadomian orogenic cycle and demonstrate the eastward extent of the Cadomian basement into the Variscan orogen. Granodiorites of similar age have so far been reported from Brittany and especially from the Saxo-Thuringian Terrane to the NE and SW of the Elbe Fault Zone. We conclude that the Saxo-Thuringian Terrane extends across the Elbe and Sudetic Marginal Fault Zones into the Fore-Sudetic Block.     

Hybrid of Shape Grammar and Morphing for Procedural Modeling of 3D Caves

Procedural modeling of three‐dimensional shapes plays a significant role in many areas nowadays. Methods based on the automation of the modeling process offer a variety of three‐dimensional structures, saving time and money. Geometry synthesis is currently used in many fields including digital cinema, electronic entertainment and simulation. There is a need to replace designers' work with intelligent automated algorithms, especially in the case of terrain modeling. This article addresses the problem of modeling virtual caves and tunnels and presents alternative solutions in the form of a hybrid system. The innovative approach combines two independent methods well known in computer graphics: shape grammars and shape morphing for modeling three‐dimensional geometry. In the modeling process, it is possible to obtain the characteristics of 3D structures with non‐spherical mesh topology. The objects and their transformations are described by functions, while production grammars define the geometry modeling process. The scene graph can be expanded by classic productions and optimized by morphing productions. Obtained shapes can be freely deformed in subsequent productions. The system offers control over the process of modeling and the resulting structure can be rendered up to a high level of realism. We also propose some measures that can be used to verify the modeling results: coefficients indicating the degree of convexity of three‐dimensional model topology based on the structure of inequality, the volume of the model, surface model and the number of model elements.     

CO 2 emission trading model with trading prices

In this paper we consider the buying/selling prices of carbon dioxide (CO₂) emission permits in trading models with uncertainty. Permission prices, although usually omitted from standard models, may significantly influence the trading market. We thus undertook to construct a more realistic trade model and to compare it with the standard one. To do this, we introduced several important changes to the standard model, namely, (1) a new optimized quality function; and (2) transactions with price negotiations between regions. We also enhanced the model using methods described in the literature to allow it to deal with reported emissions uncertainty. Additionally, we used an original method of simulating this kind of market based on a specialized evolutionary algorithm (EA).     

Binary gas sorption/desorption experiments on a bituminous coal: Simultaneous measurements on sorption kinetics,volumetric strain and acoustic emission

There is still no clear understanding of the specific interactions between coal and gas molecules. In this context sorption–desorption studies of methane and carbon dioxide, both in a single gas environment and gas mixtures, are of fundamental interest. This paper presents the results of unique simultaneous measurements of sorption kinetics, volumetric strain and acoustic emission (AE) on three tetragonal coal samples subjected to sorption of carbon dioxide and methane mixtures. The coal was a high volatile bituminous C coal taken from the Budryk mine in the Upper Silesia Basin, Poland. Three different gas mixtures were used in the sorption tests, with dominant CO₂, with dominant CH₄ and a 50/50 mixture.The experimental set-up was designed specially for this study. It consisted of three individual units working together: (i) a unit for gas sorption experiments using a volumetric method, (ii) an AE apparatus for detecting, recording and analysing AE, and (iii) a strain meter for measuring strains induced in the coal sample by gas sorption/desorption. All measurements were computer aided.The experiments indicated that the coal tested showed preferential sorption of CH₄ at 2.6 MPa pressure and exhibited comparable affinities for CH₄ and CO₂ at higher pressures (4.0 MPa). The results of chromatographic analysis of the gas released on desorption suggested that the desorption of methane from the coal was favoured. The relationship between the volumetric strain and the amount of sorbed gas was found to be non-linear. These results were contrary to common opinions on the coal behaviour. Furthermore, it appeared that the swelling/shrinkage of coal was clearly influenced by the network of fractures. Besides, the AE and strain characteristics suggested common sources of sorption induced AE and strain.The present results may have implications for the sequestration of carbon dioxide in coal seams and enhanced coalbed methane recovery (ECBM).     

Meteoroid Stream Searching: The Use of the Vectorial Elements

In this initial study, we propose a new distance function D _V involving heliocentric vectorial orbital elements. The function measures differences between: the orbital energies, the angular momentums vectors and the Laplace vectors. In comparison with the widely used D _SH criterion of Southworth and Hawkins, D _D criterion of Drummond and their hybrid D _H by Jopek, the new function contains one invariant with respect to the principal secular perturbation: the orbital energy. The new function proved to be useful in the classification amongst the IAU2003 meteoroids which we searched for streams by D _V function and also using D _SH and D _N -function given by Valsecchi et al. For major streams, the results agree very well. For minor, and near-ecliptical streams the results sometimes differ markedly.     

Late Holocene environmental changes and anthropogenic impact in Dee Why Lagoon,New South Wales

Late Holocene environmental changes were examined in Dee Why Lagoon, New South Wales, based on the sedimentological, geochemical and geochronological analysis of six cores collected from the fluvial delta and lagoon basin. The lagoon formed about 7300–7200?cal yr BP, following the post-glacial marine transgression and establishment of a sand barrier. Infilling of the lagoon occurred at a rate of 0.09–0.15?mm/yr until about 3300–3200?cal yr BP, when the barrier closed, resulting in mostly freshwater conditions, as evidenced by a change from pyrite-rich units to sediment containing little sulfur and a lack of foraminifera. Sedimentation rates increased to 0.23 then 0.43?mm/yr until about 100?years ago. Post-European land clearance led to an increase in sedimentation rates to 1.0–1.3?mm/yr on the fluvial delta, which are lower than those from other wave-dominated estuaries in New South Wales as well as those estimated by previous studies in Dee Why Lagoon. Our study shows that the fluvial delta started forming much earlier than originally thought, based on results of radiometric dating, and confirmed using sedimentological and geochemical data, as well as a critical examination of historic aerial photographs. Human impact has resulted in an increase in heavy metal (Cu, Pb, Zn) and metalloid (As) concentrations in the recent sediment, most likely attributed to stormwater discharge. Pb and As concentrations are above the ANZECC high sediment quality guideline values at the site closest to the stormwater outlet, with As-based pesticides one of the possible sources. Using the mean enrichment quotient, which is based on normalised Cu, Pb and Zn concentrations over their normalised background concentrations, we show that the surface sediments in Dee Why Lagoon are severely enriched, reflecting the recent anthropogenic impact that has also led to an increase in sedimentation rates.