11,235 research outputs found
The gastropod-symbiotic sea anemone genus Isosicyonis Carlgren, 1927 (Actiniaria : Actiniidae): a new species from the Weddell Sea (Antarctica) that clarifies the taxonomic position of the genus
A second species of the sea anemone genus Isosicyonis is described and illustrated from 16 specimens collected in the Weddell Sea (Antarctica) on the Polarstern cruises ANT XVII/3, ANT XXI/2 and ANT XXIII/8. Isosicyonis striata n. sp. is easily distinguishable externally from the other species of the genus Isosicyonis alba by its pattern: white longitudinal stripes on the column, oral disc, and tentacles. It is also distinguished by internal features including the retractor muscles, parietobasilar muscles, marginal sphincter muscles, number of mesenteries, and cnidae. The genus Isosycionis is currently only known from the Southern Ocean. Both species of Isosicyonis live in association with a gastropod, with a single sea anemone occupying almost the whole shell of its gastropod host. The description of this new species, and our re-examination of Isosicyonis alba, resolves the controversial higher taxonomic position of the genus, confirming its placement within the Endomyaria
New record of the sea anemone Kadosactis antarctica (Carlgren, 1928): re-description of an Antarctic deep-sea sea anemone, and a discussion of its generic and familial placement
Sagartiogeton antarcticus Carlgren, 1928 is an
Antarctic deep-sea species of sea anemone only known
from its holotype. The species has been assigned to the
genera Sagartiogeton and Kadosactis, and is currently
placed within the family Kadosactidae Riemann-Zu¨rneck, 1991. Kadosactis antarctica is re-described based
on 11 specimens collected during the cruise of the R/V
Polarstern ANT XIX/3 (ANDEEP-I) to the Scotia Sea
and off the South Shetland Islands (Antarctica). The
description includes a complete account of cnidae and
photographs. Because the mesogloea is thickened on the
aboral surface on the base of the tentacles, this feature
becomes a generic character of Kadosactis rather than a
differential specific character among the species of the
genus as previously proposed. Furthermore, the known
distribution of the species is enlarged to include the
southern branch of the Scotia Sea
A new species of Hormathia (Actiniaria, Hormathiidae) from the eastern Weddell Sea, Antarctica
A new species of sea anemone in the genus
Hormathia, is described and illustrated based on fortytwo specimens collected during the Polarstern cruises
ANT XV/3 and ANT XVII/3 in the Weddell Sea. The
main features of the new taxon are the crown of flattened
and hooked tubercles at the distal end of the scapus, the
regular arrangement of pointed tubercles along the column and the cnidom. The new species shares the pointed
tubercles, at least in the upper part of the scapus, with
two other species of Hormathia in the southern hemisphere: Hormathia spinosa Hertwig 1882 and H. pectinata Hertwig 188
Stephanthus antarcticus, a new genus and species of sea anemone (Actiniaria, Haloclavidae) from the South Shetland Islands, Antarctica
Stephanthus antarcticus gen. nov. et sp. nov. is
described and illustrated from six specimens collected
in the Antarctic Peninsula on the Polarstern cruises
ANT XV/3 and ANT XIX/3. The new genus is characterised by the absence of sphincter and basilar musculature, the presence of a single strong siphonoglyph with a
basal enlargement, distinct parietobasilar musculature,
tentacles without acrospheres, two cycles of six pairs
of mesenteries (only one of them perfect), and a deep
fosse with parapet; another remarkable feature is the absence of microbasic p-mastigophores. The new genus
shows characteristics of three families of soft-bottomdwelling sea anemones, namely Haloclavidae Verrill,
1899, Halcampoididae Appellöf, 1896, and Andresiidae
Stephenson, 1922. The generic characters of Stephanthus
gen. nov. are discussed and it is tentatively placed in the
family Haloclavidae
Technological Resources And Export Intensity: A Microview
This article analyses the influence of technological resources on firm-export intensity. The empirical analysis is carried out on a sample of Spanish manufacturing firms using tobit models. Our findings show that R&D investments, product and process innovations and patents positively and significantly affect the export intensity of Spanish firms
The Productivity Paradox and the New Economy: The Spanish Case
This paper studies the impact of the information and communication technologies (ICT) on economic growth in Spain using a dynamic general equilibrium approach. Contrary to previous works, we use a production function with six different capital inputs, three of them corresponding to ICT assets. Calibration of the model suggests that the contribution of ICT to Spanish productivity growth is very relevant, whereas the contribution of non-ICT capital has been even negative. Additionally, over the sample period 1995-2002, we find a negative TFP and productivity growth. These results together aim at the hypothesis that the Spanish economy could be placed within the productivity paradox.New economy, information and communication technologies, technological change, productivity paradox.
Technological sources of productivity growth in Japan, the U.S. and Germany
In this paper, we use a dynamic general equilibrium growth model to quantify the contribution of different technological sources to productivity growth in the three leading economies: Germany, Japan, and the U.S. The sources of technology are classified as representing either neutral progress or investment-specific progress. The latter can be split into two different types of equipment: information and communication technologies (ICT) and non-ICT equipment. We find that in the long run, neutral technological change is the main source of productivity growth in Germany. For Japan and the U.S., the main source of productivity growth is investment-specific technological change, mainly associated with ICT. We also find that a non negligible part of productivity growth has been due to technology specific to non-ICT equipment; this is mainly true after 1995.Productivity growth; Investment-specific progress; Neutral progress; Information and communication technology.
ICT-specific technological change and productivity growth in the US 1980-2004
This paper studies the impact of the information and communication technologies (ICT) on U.S. economic growth using a dynamic general equilibrium approach. We use a production function with six different capital inputs, three of them corresponding to ICT assets and other three to non-ICT assets. We find that the technological change embedded in hardware equipment is the main leading non-neutral force of the U.S. productivity growth and accounts for about one quarter of it during the period 1980-2004. As a whole, ICT-specific technological change accounts for about 35% of total labor productivity growth.New economy, information and communication technologies, specific-technological change, neutral-technological change.
Following the yellow brick road? The Euro, the Czech Republic, Hungary and Poland.
This paper uses a combination of VAR and bootstrapping techniques to analyze whether the exchange rates of some New Member States of the EU have been used as output stabilizers (those of the Czech Republic, Hungary and Poland), during 1993-2004. This question is important because it provides a prior evaluation on the costs and benefits involved in entering the European Monetary Union (EMU). Joining the EMU is not optional for these countries but mandatory, although there is no definite deadline. Therefore, if the exchange rate works as a shock absorber, monetary independence could be retained for a longer period. Our main finding is that the exchange rate could be a stabilizing tool in Poland and the Czech Republic, although in Hungary it appears to act as a propagator of shocks. In addition, in these three countries, demand and monetary shocks account for most of the variability in both nominal and real exchange rates.EMU, exchange rate, Structural VAR, stationary bootstraps.
Following the yellow brick road? The Euro, the Czech Republic, Hungary and Poland
This paper uses a combination of VAR and bootstrapping techniques to analyze whether the exchange rates of some New Member States of the EU have been used as output stabilizers (those of the Czech Republic, Hungary and Poland), during 1993-2004. This question is important because it provides a prior evaluation on the costs and bene?ts involved in entering the European Monetary Union (EMU). Joining the EMU is not optional for these countries but mandatory, although there is no de?nite deadline. Therefore, if the exchange rate works as a shock absorber, monetary independence could be retained for a longer period. Our main ?nding is that the exchange rate could be a stabilizing tool in Poland and the Czech Republic, although in Hungary it appears to act as a propagator of shocks. In addition, in these three countries, demand and monetary shocks account for most of the variability in both nominal and real exchange rates.EMU, exchange rate, Structural VAR, stationary bootstraps
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