22 research outputs found
Vertical distribution of periphytic diatoms in the karstic Zrmanja River (Croatia)
The small karstic Zrmanja River (69 km long) discharges into the central-eastern Adriatic Sea. High oxygen saturation and water transparency, as well as low nutrient concentrations, indicated the oligotrophic character of the river.We present the taxonomic composition and vertical distribution of diatoms attached on an artificial substrate (Plexiglass) in the lower reach of the Zrmanja River, in July 2000. Thirty attached diatoms were determined
on Plexiglass throughout the 2.5 m deep water column, and Achnanthes sp. and Fragilaria sp.were found to be the most frequent (> 89%) and abundant (> 105 cells cm–2) diatoms. The highest abundance of attached diatoms (1.2 x 106 and 7.5 x 105 cells cm–2)
was found at the depth of 0.5 m. The maximum number of diatom taxa was also found below the surface
Emergent Gravity, Matrix Models and UV/IR Mixing
We verify explicitly that UV/IR mixing for noncommutative gauge theory can be
understood in terms of an induced gravity action, as predicted by the
identification [1] of gravity within matrix models of NC gauge theory. More
precisely, we obtain the Einstein-Hilbert action by integrating out a scalar
field in the adjoint. It arises from the well-known UV/IR mixing of NC gauge
theory, which is carefully re-analyzed and interpreted in terms of gravity. The
matrix model therefore contains gravity as an IR effect, due to UV/IR mixing.Comment: 33 pages, 3 figures. V2: references adde
Anthropometric parameters and aesthetics in the making of fixed prosthodontic restaurations: Part 2
Introduction: The role of aesthetic dentistry in the field of fixed dental prosthetics is to redesign the smile, which means not only the treatment on the teeth, but also the treatment of the surrounding soft tissues. Successful therapy can be achieved by establishing the harmony between the static (teeth, gingiva) and dynamic factors (lips, cheeks, mimic muscles) at rest and when performing various functions of the orofacial system. The aim: of the study was to analyze the parameters of the oral soft tissues (gingival health, gingival height, gingival zeniths, lip line and symmetry and balance of the dentition) that affect the aesthetics of fixed prosthodontic restorations. Literature data and clinical experience were used. Conclusion: Adherence to the described parameters is of great importance in the development of aesthetic and functional fixed prosthetic restoration
Neutrino-electron scattering in noncommutative space
Neutral particles can couple with the gauge field in the adjoint
representation at the tree level if the space-time coordinates are
noncommutative (NC). Considering neutrino-photon coupling in the NC QED
framework, we obtain the differential cross section of neutrino-electron
scattering. Similar to the magnetic moment effect, one of the NC terms is
proportional to , where is the electron recoil energy.
Therefore, this scattering provides a chance to achieve a stringent bound on
the NC scale in low energy by improving the sensitivity to the smaller electron
recoil energy.Comment: 12 pages, 2 figure
Between the Vinča and Linearbandkeramik worlds: the diversity of practices and identities in the 54th–53rd centuries cal BC in south-west Hungary and beyond
Szederkény-Kukorica-dűlő is a large settlement in south-east Transdanubia, Hungary, excavated in advance of road construction, which is notable for its combination of pottery styles, variously including Vinča A, Ražište and LBK, and longhouses of a kind otherwise familiar from the LBK world. Formal modelling of its date establishes that the site probably began in the later 54th century cal BC, lasting until the first decades of the 52nd century cal BC. Occupation, featuring longhouses, pits and graves, probably began at the same time on the east and west parts of the settlement, the central part starting a decade or two later; the western part was probably abandoned last. Vinča pottery is predominantly associated with the east and central parts of the site, and Ražište pottery with the west. Formal modelling of the early history and diaspora of longhouses in the LBK world suggests their emergence in the Formative LBK of Transdanubia c. 5500 cal BC and then rapid diaspora in the middle of the 54th century cal BC, associated with the ‘earliest’ (älteste) LBK. The adoption of longhouses at Szederkény thus appears to come a few generations after the start of the diaspora. Rather than explaining the mixture of things, practices and perhaps people at Szederkény by reference to problematic notions such as hybridity, we propose instead a more fluid and varied vocabulary including combination and amalgamation, relationships and performance in the flow of social life, and networks; this makes greater allowance for diversity and interleaving in a context of rapid change
Centric diatoms of large rivers and tributaries in Hungary: morphology and biogeographic distribution
Centric diatoms of 107 different Hungarian running waters were investigated. Among them the largest was the River Danube, from which more than one hundred plankton samples were analysed by scanning electron microscopy (SEM). Only one sample was analysed from creeks, which were the smallest running waters analysed in this study. There were also channels with slow currents flowing out of rivers or connecting different rivers.In total, 41 centric taxa belonging to 11 genera were found during this study. The average number of taxa found in a single watercourse was 7, the maximum 40 and the minimum 1. Cyclotella meneghiniana was the most frequently encountered species (present in 60% ofsites). Twelve taxa were found in more than 20% of sites, 7 taxa between 5–10% and 6 taxa only in one site