bluuebunny/crossref_metadata_2025 huggingface dataset:
Sterols and linear alkylbenzenes in marine sediments from
Admiralty Bay, King George Island, South Shetland Islands
Authors: MARTINS C.C. , VENKATESAN M.I. , MONTONE R.C.
Published: February 2003

Selected sterols (coprostanol, epicoprostanol, cholesterol, cholestanol), stanone (5ßcoprostanone)
and linear alkylbenzenes (LABs) were measured in the surface sediments near Ferraz station
sewage outfalls, in Admiralty Bay, King George Island, South Shetland Islands. during the summer of
1997/98 using GC-FID and GC-MS. Total sterol concentrations varied between 0.21 and 10.4 μg g−1 dry
sediment. Cholesterol was the major sterol at all sites, except at the sewage outfall, where coprostanol
predominated. The concentration of coprostanol varied between 0.03 and 6.14 μg g−1 dry sediment, but the
majority of the samples contained levels below 0.13 μg g−1 dry sediment. The parameters
coprostanol+epicoprostanol in total sterols, coprostanol/epicoprostanol ratio versus % of cholesterol in total
sterols and versus 5ß-coprostanone concentration were used to identify the sewage impacted locations in the
study area. Only sites extending to 50m from the sewage outfall exhibited a sterol signal indicating sewage
input. Total LABs varied from <0.60 to 11.8 ng.g−1 dry sediment with the maximum level at the sewage
outfall. Faeces from different species of seals all contained large amounts of cholesterol and some 5ßcoprostanone.
Relatively low levels of coprostanol and high levels of cholesterol observed in distant sites
could be attributed to natural sources such as marine mammals.
The role of fish in the Antarctic marine food web: differences
between inshore and offshore waters in the southern Scotia Arc
and west Antarctic Peninsula
Authors: BARRERA-ORO ESTEBAN
Published: February 2003

The role of fish in the Antarctic food web in inshore and offshore waters is analysed, taking as an
example the coastal marine communities of the southern Scotia Arc (South Orkney Islands and South
Shetland Islands) and the west Antarctic Peninsula. Inshore, the ecological role of demersal fish is more
important than that of krill. There, demersal fish are major consumers of benthos and also feed on
zooplankton (mainly krill in summer). They are links between lower and upper levels of the food web and
are common prey of other fish, birds and seals. Offshore, demersal fish depend less on benthos and feed
more on zooplankton (mainly krill) and nekton, and are less accessible as prey of birds and seals. There,
pelagic fish (especially lantern fish) are more abundant than inshore and play an important role in the energy
flow from macrozooplankton to higher trophic levels (seabirds and seals). Through the higher fish predators,
energy is transferred to land in the form of fish remains, pellets (birds), regurgitation and faeces (birds and
seals). However, in the general context of the Antarctic marine ecosystem, krill (Euphausia superba) plays
the central role in the food web because it is the main food source in terms of biomass for most of the high
level predators from demersal fish up to whales. This has no obvious equivalent in other marine ecosystems.
In Antarctic offshore coastal and oceanic waters the greatest proportion of energy from the ecosystem is
transferred to land directly through krill consumers, such as flying birds, penguins, and seals. Beside krill,
the populations of fish in the Antarctic Ocean are the second most important element for higher predators, in
particular the energy-rich pelagic Myctophidae in open waters and the pelagic Antarctic silver fish
(Pleuragramma antarcticum) in the high Antarctic zone. Although the occurrence of these pelagic fish
inshore has been poorly documented, their abundance in neritic waters could be higher than previously
believed.
Surface and subsurface flows of nutrients in natural and human
impacted lake catchments on Broknes, Larsemann Hills,
Antarctica
Authors: KAUP ENN , BURGESS JAMES S.
Published: February 2003

This study aimed to use nutrients in lake inflows as proxies for assessing human impact and
separating this from natural transformations of material in the soil active layer. Nutrients, conductivity and
δ18O were monitored in surface and subsurface (using ceramic tipped piezometers) lake inflows during
summer in near natural and human impacted catchments. The nutrient levels were highly variable but
generally higher during the last weeks of the flow, in both subsurface waters and in human impacted
catchments. Up to 2000 μgN l−1 subsurface dissolved inorganic nitrogen (DIN) was measured in human
impacted catchments but only 315 μg N l−1 in natural catchments. Subsurface levels of dissolved reactive
phosphorus (DRP) were up to 310 μgP l−1 in natural catchments and up to 108 μgP l-1 in human impacted
catchments. The maximum levels of both DIN and DRP in surface inflows were much higher in human
impacted than in natural catchments. Conductivity and δ18O data showed general enrichment of snowbank
meltwater presumably through evaporation from the active layer. This combined with fluctuating nutrient
levels in catchment waters indicated that soil brines and decaying organic matter of natural and human origin
were possible sources for nutrients and other salts. Marked salinization and substantially increased DIN
levels near the research stations indicated that lake waters were receiving nutrients generated by humans.
Effects of hydrocarbon spills on the temperature and moisture
regimes of Cryosols in the Ross Sea region
Authors: BALKS MEGAN R. , PAETZOLD RON F. , KIMBLE JOHN M. , AISLABIE JACKIE , CAMPBELL IAIN B.
Published: February 2003

Hydrocarbon spills have occurred on Antarctic soils where fuel oils are utilized, moved or stored.
We investigated the effects of hydrocarbon spills on soil temperature and moisture regimes by comparing the
properties of existing oil contaminated sites with those of nearby, uncontaminated, control sites at Scott
Base, the old Marble Point camp, and Bull Pass in the Wright Valley. Hydrocarbon levels were elevated in
fuel-contaminated samples. Climate stations were installed at all three locations in both contaminated and
control sites. In summer at Scott Base and Marble Point the mean weekly maximum near surface (2 cm and
5 cm depth) soil temperatures were warmer (P<0.05), sometimes by more than 10°C, at the contaminated
site than the control sites. At Bull Pass there were no statistically significant differences in near-surface soil
temperatures between contaminated and control soils. At the Scott Base and Marble Point sites soil albedo
was lower, and hydrophobicity was higher, in the contaminated soils than the controls. The higher
temperatures at the Scott Base and Marble Point hydrocarbon contaminated sites are attributed to the
decreased surface albedo due to soil surface darkening by hydrocarbons. There were no noteworthy
differences in moisture retention between contaminated and control sites.
Ethological observations on a small group of wintering members
at Dumont d'Urville station (Terre Adélie)
Authors: TAFFORIN CAROLE
Published: February 2003

The goal of this study was to demonstrate the role of isolation on the social behaviour of
individuals and to characterize its adaptation as a function of time. The ethological method used was a
quantitative description of the spatial positioning of a sub-group of 13 wintering members during the
morning, midday and evening meals at Dumont d'Urville station. The observation protocol required the
completion of first daily and then weekly (every Thursday) observation maps at different stages of the
13 month long polar mission, from the information seminar in France, the trips outward and return aboard
the Astrolabe, the two summer campaigns at the beginning and at the end of the mission and the
overwintering period. Results, mainly expressed as human concentration and spatial dispersion indexes,
have successively shown organization, disorganization and reorganization periods of the small group
without any significant cycling. Socialisation rules promoting the group building in the early period, conflict
factors and relay steps (external perturbations breaking the isolation, transitions during group displacement
from one stage to another) promoting the maintenance of the social cohesion, are outlined in the discussion.
Seasonal observations of stable isotope variations in a valley
catchment, Signy Island, South Orkney Islands
Authors: NOON PHILIPPA E. , LENG M.J. , ARROWSMITH C. , EDWORTHY M.G. , STRACHAN R.J.
Published: February 2003

The oxygen and hydrogen isotope composition of waters in a small valley at Signy Island, South
Orkney Islands, were monitored over three summers (1999 to 2001). These stable isotopes track water
movement through the catchment, especially seasonal precipitation and snow melt. All samples fall close to
the regional meteoric water line but factors other than air temperature cause year-to-year variability.
Residence times are in the order of days thus the lake water provides an average of precipitation falling only
a few days before, except in the winter when the lakes are effectively closed. Freezing of surface waters
preserves the isotope signature of the underlying waters from the previous summer. In spring, meltwaters
from winter snow are isotopically depleted having δ18O and δD as low as -13‰ and -100‰ (VSMOW). Ice-
cover break-up in late December allows complete water column mixing. By February, the lakes are
relatively enriched isotopically (δ18O -9‰) by summer precipitation. Precipitation isotopic composition at
Halley Station, Brunt Ice Shelf, is similar, illustrating the broad-scale effects of the Weddell Sea cyclonic
atmospheric circulation. These data form a useful reference data-set for the ground-based validation of
atmospheric models and palaeoclimate reconstructions in this isolated sector of the South Atlantic Ocean.
Spatial variation in the community structure of intertidal habitats
at Macquarie Island (sub-Antarctic)
Authors: SMITH STEPHEN D.A. , SIMPSON RODNEY D.
Published: February 2003

The shore environments of most sub-Antarctic islands have been described in a number of
previous studies. However, there have been few attempts to quantify the variation in population and
community patterns over different spatial scales. The objectives of this study were to provide an analysis of
differences in the community structure of the biota of three exposed shore zones and of the macrofauna
inhabiting holdfasts of the kelp Durvillaea antarctica across spatial scales of hundreds of metres, kilometres,
and between a sheltered and exposed coast. Data were collected using a combination of quadrat, transect and
direct sampling methods over the 1994–95 summer season. The results indicated that there were significant
differences between coasts for some of the biotic variables in most of the habitats examined but that
differences at the smaller spatial scales were more often significant. Thus, although wave exposure exerts an
obvious effect on the shore biota of Macquarie Island, these effects are modified by other factors operating at
smaller spatial scales. For the holdfast macrofauna, the overall patterns of community structure are likely to
be due to the differential response of the component taxa to variation in holdfast volume and holdfast
sediment content as well as other, currently undetermined factors.
Biogeographical affinities of polychaetes from Îles Crozet
Authors: SICINSKI JACEK , GILLET PATRICK
Published: February 2003

The study of polychaetes from the Marion Dufresne expedition to the Îles Crozet in 1982
provided 45 species from depths ranging from 50–1055 m. The most abundant was Eunice pennata, found at
all depths and in all types of substratum in about 66% of the samples. This species with Laetmonice
producta, Harmothoe spinosa and Lanice marionensis made up over 50% of all polychaete specimens. A
homogenous polychaete assemblage dominated by the above mentioned group of species was encountered
in the shallower stations (100–300 m). A mosaic-like and less abundant polychaete fauna with some
characteristic, abundant species: Amage sculpta, Laetmonice wyvillei, Leanira quatrefagesi and Melinna
cristata was encountered in the deeper stations (300–1055 m). Clear similarities between the polychaete
fauna of Îles Crozet and soft-sediment polychaete assemblages of Marion and Prince Edward Islands were
noticed. No such affinity was encountered with the polychaete fauna of Îles Kerguelen. Their position in
relation to the Polar Front as well as possible differences in bottom deposits (calcareous versus siliceous)
may in part explain these dissimilarities. The biogeographical status of Kerguelen Islands is also discussed.
A 1000-year record of Adélie penguin diets in the southern Ross Sea
Authors: POLITO MICHAEL , EMSLIE STEVEN D. , WALKER WILLIAM
Published: February 2003

Non-krill prey remains were recovered from ornithogenic sediments at three active Adélie
penguin colonies on Ross Island, to assess long-term dietary trends in this species. Radiocarbon dates place
the age of these deposits from a maximum of 947 years ago to the present. We identified 12 taxa of fish and
two of squid with the Antarctic silverfish (Pleuragramma antarcticum) as the most abundant prey species
represented at all sites. In addition, silverfish have decreased in importance in Adélie penguin diet over the
past 600 years, perhaps in response to climate change since the onset of the Little Ice Age, though it remains
much more abundant in current penguin diet in the Ross Sea than in the Antarctic Peninsula. Other prey taxa
reflect the diversity of prey selection by Adélie penguins in Antarctica.
The sedimentary geology, palaeoenvironments and
ichnocoenoses of the Lower Devonian Horlick Formation, Ohio
Range, Antarctica
Authors: BRADSHAW MARGARET A. , NEWMAN JANE , AITCHISON JONATHON C.
Published: February 2003

Six ichnocoenoses in the clastic Devonian Horlick Formation (max. 56 m) confirm the nearshore
marine character of eight of the nine lithofacies present. Abasal sand sheet overlies a weathered granitic land
surface (Kukri Erosion Surface) on Cambro–Ordovician granitoids. The level nature of this surface and the
way it cuts across weathering profiles, suggests that the surface had been modified by marine processes prior
to deposition. The basal sand sheet (Cross-bedded Sand sheet Lithofacies) contains tidal bundles, and at its
top, abundant Monocraterion (Monocraterion Ichnocoenosis). The second sand sheet (Pleurothyrella
Lithofacies) is heavily burrowed and shows alternating periods of sedimentation, burrowing, and erosion
below wave base as the sea deepened (Catenarichnus Ichnocoenosis). With increasing transgression, finer
sediments were deposited (Laminated Mudstone and Feldspathic lithofacies) in an unstable pattern of coarse
sandbars and finer troughs (Cruziana-Rusophycus and Arenicolites ichnocoenoses) crossed by active
longshore marine channels (Poorly-sorted Lithofacies, Spirophyton Ichnoocoenosis). Short-lived but
powerful storms produced thin shelly tempestites (Shell-bed Lithofacies), whereas sporadic, very thin
phosphate rich beds (Phosphatic Lithofacies) may have resulted from marine transgressions across the basin.
The deepest water is probably represented by sediments of the Spirifer Lithofacies (Rosselia Ichnocoenosis).
The Schulthess Lithofacies is regarded as fluvial, deposited in the lower reaches of a river draining a land
area that lay towards Marie Byrd Land. Channels in the basal sand sheet indicate movement to the southwest,
but orientation became more variable higher in the sequence. Four new measured sections are figured.
The relationship of the Ohio Range to the rest of Antarctica during the Devonian is suggested.
Late Quaternary environment of southern Windmill Islands, East
Antarctica
Authors: KIRKUP HELEN , MELLES MARTIN , GORE DAMIAN B.
Published: February 2003

Analyses on a sediment core collected from the Windmill Islands, East Antarctica are used to
demonstrate that climatic conditions in this region prior to the Last Glacial Maximum were similar to those
during the Holocene and that the area was overrun by ice at some stage between 26 kyr BP and the onset of
biogenic sedimentation 11 kyr BP. The 10.9 m long core was taken from a marine inlet (epishelf lake) on
Peterson Island and is predominantly a sapropel of Holocene age. Material in the lower part of the core
includes a till layer lain down during the last glacial in the region and below this till is material which has
been dated to 26 kyr BP. Geochemical analyses conducted on the core demonstrate similarities between the
Holocene sequence and the preglacial material. The Holocene sequence shows enhanced biogenic
production and periods of open water around 4 kyr BP, suggesting a climatic optimum around that time. A
subsequent decline in conditions, probably a colder climate with greater extent of sea ice, is evident from
1 kyr BP to the present. The data support results from ice core studies on nearby Law Dome, which suggest
there was a period of warming around 11.5 to 9 kyr BP, that recent summer temperatures are low relative to a
few centuries ago, and that increasing winter temperatures are the main contributing factor to a recent overall
warming in the region.
Electron microprobe characterization of ash layers in sediments
from the central Bransfield basin (Antarctic Peninsula): evidence
for at least two volcanic sources
Authors: FRETZDORFF S. , SMELLIE J.L.
Published: February 2003

Bransfield Strait, a narrow active rift with three submarine basins, separates the South Shetland
Islands from northern Antarctic Peninsula. Volcanism in Bransfield Strait commenced prior to 0.75 Ma and
continues, with recent subaerial eruptions at Deception, Bridgeman and Penguin islands, submarine
hydrothermal activity and numerous young basaltic seamounts located along the rift axis. Gravity cores were
collected from five locations within the central Bransfield basin. Diatomaceous mud interbedded with
terrigenous detritus and discrete ash layers up to 10 cm thick are the commonest sediment types in all the
cores. The major element compositions of glass shards within the ash layers are, apart from the uppermost
layer, compositionally similar to pyroclastic units preserved on Deception Island, a young (<0.75 Ma) active
stratovolcano. The uppermost ash layer cannot be closely matched compositionally to any known source in
the Antarctic–Scotia Sea–southern South America region. Its presence indicates that a volcanic centre other
than Deception Island contributed ash to the Bransfield basin. Based on the shallow stratigraphical position
of the compositionally distinctive ash layer, only a few decimetres beneath the seafloor, its source volcano
was probably active in historical times (<few hundred years).
Geochemistry of the Darwin Glacier region granitoids, southern
Victoria Land
Authors: SIMPSON A.L. , COOPER A.F.
Published: February 2003

The Darwin Glacier region is located between the Carlyon
and Darwin glaciers in southern Victoria Land, Antarctica
(Fig. 1). Previous work on Ross Orogeny granitoids of the
Darwin Glacier region is mutually conflicting. Haskell et al.
(1965) mapped three plutons, the Carlyon Granodiorite,
Mount Rich Granite and Hope Granite, Felder & Faure
(1990) did not recognise the Hope Granite, and Encarnación
& Grunow (1996) interpreted the entire area as underlain by
a single intrusion, the Brown Hills pluton. Fieldwork during
the 2000 field season and subsequent geochemical and
geochronological analysis described here indicates the
presence of three distinctive granitic suites, emplaced
during Cambrian times. These include the Foggy Dog
Granite (FDG) suite, the Darwin calcic suite and the Cooper
Granodiorite.
Population structure of the Patagonian toothfish around Heard,
McDonald and Macquarie Islands
Authors: APPLEYARD SHARON A. , WARD ROBERT D. , WILLIAMS RICHARD
Published: February 2003

Two mitochondrial DNA regions and seven microsatellite loci were examined in Patagonian
toothfish from three locations in the Southern Ocean (Macquarie Island, five collections; Heard and
McDonald Islands, four collections; Shag Rocks/South Georgia area, one collection). Striking mtDNA
heterogeneity was detected between the three fishing locations (FST=0.445, P<0.001), but spatial and
temporal collections within the same location were not significantly different. No significant overall
microsatellite differentiation between the three locations was apparent (FST=−0.009, P=0.785). However,
some individual loci showed small but significant differentiation, which in each case was attributable to
between rather than within-location differentiation. Greater differentiation of mtDNA can, in principle, be
explained either by female philopatry and male dispersal, or by its greater sensitivity to changes in effective
population size. The latter seems more likely as tagging indicates that toothfish is generally a sedentary
species. The genetic heterogeneity between the three locations indicates restricted gene flow, with the fish at
each location comprising independent units. Depletion in one location is therefore unlikely to be quickly
replaced by immigration from another.
La structure des propositions adverbiales du français: arguments sociolinguistiques
Authors: Beaulieu Louise , Balcom Patricia
Published: February 2003

D'après Emonds (1985), les conjonctions de subordination du français sont des prépositions qui ont comme complément TP, une projection dont la tête est Temps. Selon Jones (1996), le complément de ces prépositions est un CP, une projection dont la tête est Complémenteur.

Cet article présente une analyse sociolinguistique des conjonctions de subordination du français acadien parlé dans le nord-est du Nouveau-Brunswick au Canada (FANENB) qui montre que l'hypothèse de Jones rend mieux compte des données du FANENB et de celles du français normatif. L'explication la plus simple des divergences observées entre les propositions adverbiales de ces deux variétés se résume à une différence dans la spécification du trait [interrogatif] du complémenteur et à la force ou la faiblesse de ce trait.
Identifying a French-specific laughter particle
Authors: Ellis Yvette
Published: February 2003

Aspirated sounds placed in a stream of talk prior to the onset of laughter are oriented to by interactants as minimal-equivocal laugh particles. These particles are available to carry out various interactional tasks, signalling an opportunity for co-participants to co-ordinate their laughter, to join in an episode of shared laughter for example. They may also contribute to keying actions as non-serious.

The analysis of data from my corpus of French talk-in-interaction has revealed several instances of a voiceless palatal fricative following a word-final high front vowed [i]. This sound will be shown to occupy interactional slots generally associated with minimal-equivocal laughter particles. From evidence of its placement in sequences of turns keyed as non-serious, accompanying dispreferred actions, and in a terminal position in interactional sequences, the voiceless palatal fricative will be shown to be oriented to by French speakers as a minimal-equivocal laugh particle.
Phonostylistique des annonceurs de la radio: Etude prosodique de textes radiophoniques
Authors: Oakes Leigh
Published: February 2003

En dehors des lexiques spécialisés et des structures syntaxiques spécifiques, c'est la prosodie qui fait que tous reconnaissent sans hésitation les textes radiophoniques. Ceux-ci se distinguent clairement du parler spontané et, dans une certaine mesure, d'autres formes de l'écrit oralisé: l'accentuation barytonique, des patrons rythmico-mélodiques spécifiques et une prosodie qui assume un rôle particulier dans l'organisation de la phrase seraient tous motivés par un désir de la part de l'annonceur de faire apparaître une qualité professionnelle.

Après un bref survol des descriptions du style oral des présentateurs faites par d'autres chercheurs, nous proposons ici de faire une analyse qualitative et quantitative de nos propres données recueillies en 1994 auprès des annonceurs de Radio France Internationale, dans le but de confirmer, modifier ou réfuter quelques-unes des hypothèses proposées auparavant. Enfin, nous mettrons en lumière quelques aspects de la prosodie des annonceurs de radio qui restent à étudier de plus près.
La production du E caduc facultatif est-elle prévisible? Un début de réponse
Authors: Racine Isabelle , Grosjean François
Published: February 2003

Dans cette étude, nous examinons les facteurs qui influencent la production des mots comportant un E caduc facultatif en syllabe initiale. Nous avons demandé à des locuteurs francophones de raconter quatre histoires comportant des mots où le E caduc est facultatif, et nous avons ensuite calculé, pour chaque mot, un taux de production avec effacement. Afin de prédire les taux obtenus, sept facteurs ont été choisis et, pour chacun d'eux, un coefficient de corrélation a été calculé. Une combinaison des trois facteurs les plus importants a ensuite été utilisée pour déterminer le pourcentage de variation du E caduc facultatif qui peut être expliqué. Il en ressort que la production du E caduc facultatif est en partie prévisible.
Analyse polyphonique de bien, marqueur du discours
Authors: van Baardewijk-Rességuier Jacqueline
Published: February 2003

Bien marqueur du discours oriente systématiquement l'énoncé vers le positif, mais contrairement à l'adverbe de manière ou au substantif, le marqueur bien est implicitement porteur de négativité. Il introduit dans l'énoncé un parcours entre ces pôles opposés, que nous analysons ici en combinant la théorie polyphonique et celle des topoï: les énonciateurs sont les représentants des points de vue qui s'affrontent en deuxième ou troisième ligne et sont responsables des différents revirements dans l'argumentation. L'analyse du mécanisme argumentatif fondamental déclenché par bien marqueur est basée sur un corpus de plusieurs centaines d'occurrences, ce qui nous a permis de dégager un certain nombre de valeurs contextuelles de bien suivant qu'il apparaît seul ou en combinaison avec d'autres connecteurs tels mais ou donc.
The rhetoric of the royal chamber in late medieval London, York and Coventry
Authors: Liddy Christian D.
Published: February 2003

In the late medieval period several English cities claimed the distinction of being a royal chamber: London and York referred to themselves as the ‘king's chamber’, whilst Coventry called itself the ‘prince's chamber’. Examining the meaning of the metaphor of the chamber, this article provides a new perspective on the way in which cities negotiated their relations with the crown and shows how the chamber became an important aspect of corporate urban identity from the fourteenth to the seventeenth centuries.
From conflict to co-operation: urban improvement and the case of Dundee, 1790–1850
Authors: Miskell Louise
Published: February 2003

This article offers a case study of urban improvement in Dundee, where the unco-ordinated efforts of different interest groups were largely adequate for the needs of the town in the first half of the nineteenth century, after which a more centralized approach evolved to address urban problems on a new scale. The Dundee case offers some explanations for this shift, which was mirrored in many other British towns.
Pioneers in the Victorian provinces: veterinarians, public health and the urban animal economy
Authors: Hardy Anne
Published: February 2003

From the 1850s in Britain, concerns were growing about the role of animals in transmitting disease to man, whether through the food chain or through infection. While London is often seen as providing a model for public health reform, it was the great provincial cities that initiated veterinary involvement in public health in the closing years of the century. The emergence of this new strand of public health activity is the subject of this paper.
Rebuilding the industrial town: wartime Wolverhampton
Authors: Larkham Peter J.
Published: February 2003

There are well-known reconstruction plans for various UK cities produced during and after the Second World War, but little attention has been paid to those towns suffering little damage, or whose plans were not drawn up by the usual eminent consultants. This paper explores the process of preparing such a plan for Wolverhampton, in the English West Midlands. Here, a ‘technocentric’ plan is evident, typical of the 1940s reconstruction plans, but one with roots stretching back a decade into the middle 1930s; one whose key impetus was the Borough Surveyor, but which was prepared for a major programme of public involvement and consultation. Although this plan was not carried out in this form, it set the agenda for the next forty years of development in planning thought and in changing urban form. It was pivotal in the history of the town and its restructuring from the middle of the twentieth century.
The construction and form of modern cities: exploring identities and community
Authors: Hayes Nick
Published: February 2003

‘Urban historians’, we are told, are ‘obliged to be more eclectic’ than other scholars of the city. The volumes covered by this review certainly speak to the rich diversity of urban history making.* While the others can take a ‘well-defined disciplinary perspective’ – as sociologists, geographers, etc. – only we are expected to ‘study the interaction of the urban fabric on the social fabric’ in its ‘unique spatial setting’ across social, economic and political boundaries (and of course through time). This is a rhetoric – an ideal, perhaps – with which most of us, doubtless, are already familiar. But how does it translate into practice? In our everyday imperfect world of time constraints a nominal commitment to eclecticism can instead spawn specialization, and thus a lack of cross-disciplinary ‘cohesion’, so that the ‘umbrella’ of diversity instead becomes an agency for introversion. To be truly eclectic, therefore, presumably urban historians need to be not only better read (and/or brighter) than other academic colleagues, but also better resourced! Yet before we all rush to our respective departmental heads to make a claim, we need to ask, too, whether this declaration of eclecticism is little more than yet another ‘idealized’ story that we tell about ourselves: part of our identity, of how we would like to be seen, an affirmation of our self-view. Is it as ‘imagined’, for example, as other forms of identity – a construct to serve a purpose? Is it there to make us feel special, valued and privileged?
City visions and urban theory
Authors: Green David R.
Published: February 2003

The nightmare (or is it challenge?) that surely all reviewers face at one time or another is to be provided with a set of books that have little or nothing in common. Conversely, the nightmare that review editors face is to have these books collect dust in the same proportion as their conscience grows. The challenge is to reduce the proportion of guilt and dust in sufficient measure whilst at the same time avoiding posing an impossible task for the hapless reviewer. Though all have their merits to a greater or lesser extent, in this case the reader is left to judge for him- or herself whether there is much, if any, coherence to the books under review.
Current bibliography of urban history
Authors: Smith John , Herbert Joanna , Verdier Nicolas
Published: February 2003

This bibliography is a continuation of and a complement to those published in the Urban History Yearbook 1974–91 and Urban History 1992–2001. The arrangement and format closely follows that of previous years. There is an index of towns on p. 509. The list of abbreviations identifies only those periodicals from which articles cited this year have been taken.
Free oxygen radicals are generated at the time of aspiration of oocytes from ovaries that have been stored for a long time
Authors: Iwata Hisataka , Ohota Mayuko , Hashimoto Syu , Nagai Yoshiharu
Published: February 2003

In ischaemic tissues, reperfusion induces acute injury and functional changes. In this work, ovaries were stored for various times, and superoxide dismutase (SOD) and dimethylthiourea (DTMU) were used at the time of oocyte aspiration. We then attempted to determine whether free oxygen radicals are generated at oocyte aspiration and whether they impair the developmental competence of oocytes. Over 2 mM of DMTU and 1000 U/ml of SOD significantly improved the rate of blastulation 8 days after insemination. For ovaries that were preserved for 3 and 7 h, using antioxidants also significantly improved the rate of blastulation 8 days after insemination. However, no effect was observed on oocytes from ovaries preserved for 1 h. We examined how the antioxidants affected the presence of germinal vesicles, chromatin configuration, and polar body extrusion 6 or 21 h after culture. Chromatin configuration was classified into three groups according to the amount of chromatin condensation (group 1, strong condensation; group 2, moderate; group 3, slight). Storing ovaries for a long time decreased the frequency of occurrence of group 2, but increased groups 1 and 3. However, using antioxidants at oocyte aspiration decreased the frequency of group 3 and increased group 1. Moreover, there was no difference in the rate of germinal vesicle breakdown and polar body extrusion. Our results show that preserving ovaries for a long time induces the generation of free oxygen radicals and that these chemicals impair oocyte viability. Using antioxidants at oocyte aspiration was beneficial for embryo production.
MAPK/ERK kinase (MEK) signalling is required for resumption of meiosis in cultured cumulus-enclosed pig oocytes
Authors: Meinecke B. , Krischek C.
Published: February 2003

Resumption of meiosis of mammalian oocytes is facilitated by the maturation promoting factor (MPF) and accompanied by activation of mitogen activated protein kinases (MAPK) which are phosphorylated by the MAPK kinase (MEK). In this study we examined the effects of PD 98059, which inhibits the activity of MEK, on in vitro maturation of pig oocytes. Cumulus-oocyte complexes (COCs) were cultured in the presence or absence of the drug (50 μM) for various time periods. To elucidate the influence of cumulus cells, COCs were first cultured in inhibitor-free medium, subsequently denuded, and incubated further in PD 98059 supplemented medium. Reversibility of drug action as tested following PD 98059 treatment of COCs by transferring them to drug-free medium. Culture of COCs in medium supplemented with PD 98059 prevents resumption of nuclear maturation in the majority of COCs. This inhibition was reversible and accompanied by a non-activation of both MAP and MPF. Addition of the MEK inhibitor to extracts of in vitro matured oocytes revealed that the kinase activities were not directly influenced by the inhibitor, suggesting a link between MAP and MPF kinases. Preincubation of COCs in inhibitor-free medium for 6 h followed by further culture of COCs or denuded oocytes in the presence of PD 98059 for various periods resulted in elevated MAP and MPF kinase activities, indicating an early and transient MEK signalling in the oocyte itself. These results support the idea that MAP and MPF are involved in the induction of germinal vesicle breakdown in porcine oocytes.
Sex determination of buffalo embryos (Bubalus bubalis) by polymerase chain reaction
Authors: Manna Laura , Neglia Gianluca , Marino Marcella , Gasparrini Bianca , Di Palo Rossella , Zicarelli Luigi
Published: February 2003

The aim of this study was to identify a simple, rapid method for sex determination of in vitro produced buffalo embryos, amplifying Y-chromosome-specific repeat sequences by polymerase chain reaction (PCR). Buffalo oocytes collected from slaughtered animals were matured, fertilised and cultured in vitro for 7 days. On day 7 embryos were evaluated and divided in to six groups according to developmental stage (2, 4, 8, 16 cells, morulae and blastocyst). Each embryo was stored singly in phosphate-buffered saline at −20 °C until PCR. Two different methods of extraction of DNA were compared: a standard procedure (ST), using a normal extraction by phenol-chloroform, isoamyl alcohol and final precipitation in absolute ethanol and a direct procedure (DT), using a commercial kit (Qiaquik-Qiagen mini blood). A pair of bovine satellite primers and two pairs of different bovine Y-chromosome-specific primers (BRY4.a and BRY.1) were used in the PCR assay on embryos and on whole blood samples collected from male and female adult buffaloes, used as control. The trial was carried out on 359 embryos (193 for ST and 166 for DT). When DNA samples from blood were amplified, the sex determined by PCR always corresponded to the anatomical sex. Embryo sexing was not possible in two embryos in ST and one embryo in DT. Both extraction protocols recovered sufficient quantities of target DNA at all developmental stages, but the time required for the ST (24 h) limits its use in embryo sexing and supports the use of commercial extraction kits (5 h).
Review of the longevity of the second polar body in the mouse
Authors: Bartholomeusz Roland
Published: February 2003

The polar bodies are derived from meiotic divisions during oogenesis and are contained together with the oocyte within the zona pellucida. Fertilisation triggers the second meiotic division, at which time the second polar body (PB2) is formed (Hogan et al., 1986; Schatten et al., 1988; Johnson & Everitt, 1995) There is no clear evidence on the fate of the polar bodies in any mammal including the mouse, which is the commonly used research model. However, the polar bodies are generally considered as waste material, and therefore not essential to embryo development. In recent years the polar bodies have gained prominence as they have been used in humans for pre-implantation genetic diagnostic purposes (PGD), of single gene disorders, such as determining whether an embryo may have inherited the cystic fibrosis allele from its mother (Munne et al., 1995; Strom et al., 1998; Rechitsky et al., 2000). PB2 also has a potential use in cloning, for the harvesting of stem cells. Wakayama et al. (1997) have shown that PB2 has the same genetic potential as the female pronuclei and can be used for the production of normal offspring in mice. The successful use of PB2 for these purposes is dependent on its age, for its longevity, rate and nature of degeneration has yet to be determined. While there is little doubt that the first polar body (PB1) experiences a necrotic fate, the same cannot be said for PB2, which may experience an apoptotic fate. Furthermore if PB2 experiences an apoptotic fate rather than a necrotic one, it would not only be the earliest evidence of apoptosis in a mammal but also provide an excellent research model for the study of apoptosis.
DNase I and II present in avian oocytes: a possible involvement in sperm degradation at polyspermic fertilisation
Authors: Stępińska Urszula , Olszańska Bożenna
Published: February 2003

During polyspermic fertilisation in birds numerous spermatozoa enter the eggs, in contrast to the situation in mammals where fertilisation is monospermic. However, in birds only one of the spermatozoa which have entered an egg participates in zygote nucleus formation, while the supernumerary spermatozoa degenerate at early embryogenesis. Our previous work has demonstrated the presence in preovulatory quail oocytes of DNase I and II activities able to digest naked λDNA/HindIII substrate in vitro. In the present studies, the activities of both DNases in quail oocytes at different stages of oogenesis and in ovulated mouse oocytes were assayed in vitro using the same substrate. Degradation of quail spermatozoa by quail oocyte extracts was also checked. Digestion of the DNA substrate was evaluated by electrophoresis on agarose gels. The activities of DNase I and II in quail oocytes increased during oogenesis and were the highest in mature oocytes. The activities were present not only in germinal discs but also in a thin layer of cytoplasm adhering to the perivitelline layer surrounding the yolk. At all stages of oogenesis the activity of DNase II was much higher than that of DNase I. DNA contained in spermatozoa was also degraded by the quail oocyte extracts under conditions optimal for both DNases. In contrast to what is observed in quail oocytes, no DNase activities were detected in ovulated mouse eggs; this is logical as they would be useless or even harmful in monospermic fertilisation. The possible role of DNase activities in avian oocytes, in degradation of accessory spermatozoa during polyspermic fertilisation, is discussed.
Identification of differentially expressed mRNAs in bovine preimplantation embryos
Authors: Kaňka J. , Bryova A. , Duranthon V. , Oudin J.-F. , Peynot N. , Renard J.P.
Published: February 2003

We have characterised the changes in preimplantation embryos that occur in the mRNA population during the transition from maternal to zygotic control of embryogenesis. We connected the mRNA differential display method and RT-PCR based method that allows amplification of the whole population of messengers. In the early stages of development we have further characterised the level of individual mRNAs with the help of semiquantitative RT-PCR used with specific primers. This report concerns four of 12 cDNA fragments that appeared to be differentially expressed between the 4- and late 8-cell stages. A transcript corresponding to fragment no. 1/12 appears to be analogous to the maternal mRNA since it is abundant in 1-, 2-, 4- and 8-cell embryos and rapidly decreases in the later stages. A similar pattern of expression was revealed in the transcript corresponding to fragment no. 8/9. A transcript corresponding to fragment no. 20/8 is newly synthesised from the embryonic genome at the late 8-cell stage and its amount rapidly increases during the following stages. This messenger shows a 91.7% identity with mRNA for human S3A ribosomal protein and 92.2% identity with mRNA for Felis domesticus S3A ribosomal protein. A transcript corresponding to fragment no. 8/19 is stage-specific, being newly synthesised from an embryonic genome at the late 8-cell stage and decreasing in the later stages. This messenger shows 86.6% identity with a mouse mRNA for proline-rich protein and 91.6% identity with human mRNA for KIAA-0058 gene. A complex of these molecular markers represents a suitable tool for answering questions concerning the molecular control of major gene activation during bovine embryogenesis.
Development of mouse embryos derived from oocytes reconstructed by metaphase I spindle transfer
Authors: Cheng Yong , Lei Lei , Wen Duan-Cheng , Zhu Zi-Yu , Sun Qing-Yuan , Chen Da-Yuan
Published: February 2003

Abnormal oocyte spindle is frequently associated with the infertility of aged women. Directly manipulating the metaphase I (MI) spindle may be a feasible method to overcome this kind of problem. Here, we report that the MI meiotic spindle can be removed from MI mouse oocytes and will autonomously divide into two daughter cells with the same size, morphology and an equal number of chromosomes after culture for 5 h in maturation medium. The division rate of the MI spindle reached 56% after 10-15 h of culture. After transferring the MI meiotic spindle into synchronous ooplasm by electrofusion, about 61% of the reconstructed oocytes continued to complete the first meiosis and extruded a normal first polar body. The matured reconstructed oocytes can also be fertilised. Approximately 50% of the 2-cell embryos developed to the morula stage after in vitro culture.
The effect of PD98059 on MAPK regulation in cumulus-enclosed and cumulus-free mouse oocytes
Authors: Kalous Jaroslav , Kubelka Michal , Motlík Jan
Published: February 2003

The effect of the p42/44 mitogen-activated kinase (MAPK) inhibitor, PD98059, on MAPK activation and meiosis resumption in mouse oocytes was studied. When germinal vesicle (GV)-stage denuded oocytes (DOs) were cultured continuously in 50 μM PD98059, germinal vesicle breakdown (GVBD) was postponed for 2-3 h. MAPK phosphorylation and activation was delayed as well. However, PD98059 did not impair histone H1 kinase activation. After 14 h of culture there was no significant difference in the rate of DOs reaching metaphase II (MII) arrest in either control or experimental conditions. The effect of PD98059 on MAPK inhibition was further tested in epidermal growth factor (EGF)-treated oocyte–cumulus complexes (OCCs). Exposure of GV-stage OCCs for 5 min to EGF (10 ng/ml) induced a considerable increase in MAPK phosphorylation. After OCCs were further cultured in 50 μM PD98059 a rapid dephosphorylation of MAPK was induced. Already after 1 min of treatment the non-phosphorylated form of MAPK dominated, indicating the high effectivity of PD98059. This result indicates that short EGF/PD98059 treatment of OCCs induced MAPK phosphorylation/dephosphorylation in cumulus cells only. As only a transient delay in MAPK phosphorylation and activation was observed in PD98059-treated DOs we conclude that there is also another PD98059-nonsensitive pathway(s) leading to MAPK activation in mouse oocytes. The data obtained suggest that meiosis resumption in mouse oocytes is somehow influenced by the MEK/MAPK activation pathway.
Different activation treatments for successful development of bovine oocytes following intracytoplasmic sperm injection
Authors: Ock S.A. , Bhak J.S. , Balasubramanian S. , Lee H.J. , Choe S.Y. , Rho G.J.
Published: February 2003

In this study, the developmental capacity and cytogenetic composition of different oocyte activation protocols was evaluated following intracytoplasmic sperm injection (ICSI) of in vitro matured bovine oocytes. Motile spermatozoa selected by Percoll density gradient were treated with 5 mM dithiothreitol (DTT) and analysed for ultrastructural changes of the head using transmission electron microscopy (TEM). The alterations in sperm morphology after DTT treatment for different times (15, 30 and 60 min) were 10%, 45-55% and 70-85%, respectively. Further, a partial decondensation of sperm heads was observed after DTT treatment for 30 min. Oocytes were injected with sperm treated with DTT for 30 min. In group 1, sperm injection was performed without any activation stimulus to the oocytes. In group 2, sham injection without sperm was performed without activating the oocytes. Oocytes injected with sperm exposed to 5 μM ionomycin for 5 min (group 3), 5 μM ionomycin + 1.9 mM dimethylaminopurine (DMAP) for 3 h (group 4) and 5 µM ionomycin + 3 h culture in M199 + 1.9 mM DMAP (group 5) were also evaluated for cleavage, development and chromosomal abnormality. Cleavage and development rates in groups 1, 2 and 3 were significantly (p < 0.05) lower than those in groups 4 and 5. The incidence of chromosomal abnormality in the embryos treated directly with DMAP after ionomycin (group 4) was higher than in group 5. We conclude that immediate DMAP treatment after ionomycin exposure of oocytes results in arrest of release of the second polar body, and thus leads to changes in chromosomal pattern. Therefore, the time interval between ionomycin and DMAP plays a crucial role in bovine ICSI.