bluuebunny/crossref_metadata_2025 huggingface dataset:
Reproductive cycle of the blue swimmer crab, Portunus pelagicus, off southern Australia
Authors: Kumar Martin S. , Xiao Yongshun , Venema Sonja , Hooper Graham
Published: September 2003

The proportion of berried (externally egg-bearing) females, fecundity, gonadosomatic index, and egg size of the blue swimmer crab Portunus pelagicus off southern Australia were examined by analysing data from samples of commercial catches using generalized linear models. Ovarian development was studied morphologically and histologically. Female blue swimmer crabs spawn from October to January and can spawn more than once per season. The fecundity of female blue swimmer crabs initially increased with carapace width, maximized at a carapace width of 134 mm, and decreased thereafter. Thus, fecundity increased 83.9% with an increase of carapace width from 105 to 125 mm, implying a single large female can produce as many eggs as two or more small females. The gonadosomatic index of female crabs from Spencer Gulf increased 2.4% from October 1998 to November 1998, increased an additional 15.9% by December 1998, and then decreased 62.3% to its minimum in January 1999. Gonadosomatic index also increased with 1/3 power of their body weight. Thus, the commonly used gonadosomatic index is overly simplistic for blue swimmer crabs. Unlike tropical or subtropical female blue swimmer crabs which often continually spawn, those off southern Australia spawn only in certain times of the year. The implications of this work lead to suggestions for three management measures for the commercial fishery: maintaining the prohibition of catching berried females, extending the seasonal closure from October to January, and maintaining the current legal minimum carapace width of 110 mm.
Tenure of individual larval trematode infections in an estuarine gastropod
Authors: Curtis Lawrence A.
Published: September 2003

Ilyanassa obsoleta(Mollusca: Gastropoda) is an abundant inhabitant of salt marshes and tidal flats on the east coast of North America. Populations of this snail may be heavily infected by larval trematodes. Three species were observed in this work,Himasthla quissetensis, Lepocreadium setiferoides, andZoogonus rubellus. Mostly as single-species infections, all occupy snail tissues as parthenitae that produce cercariae, which are released from the snail to infect the next host. By periodically testing snails for cercarial emission, single-species infections are here shown to persist over six summers and double-species infections are also noted to be long-lived. Among the 32 snails followed, 25 released the same (or no) cercariae throughout observation periods averaging three years. The other seven indicated infection changes, but only two of these are judged to reflect actual changes. The probability that a snail changed infection status in this study is thus 2.1% y−1.Ilyanassa obsoletaindividuals, and apparently their trematode infections, can persist for decades. Because species colonize and get evicted infrequently, sets of trematode species infecting I.obsoletaindividuals (infracommunities) are concluded to be isolationist in character.
In situ absorption efficiency processes for the cultured mussel Mytilus galloprovincialis in Ría de Arousa (north-west Spain)
Authors: Babarro José M.F. , Fernández-Reiriz María José , Labarta Uxío
Published: September 2003

Mussel seed Mytilus galloprovincialis from two origins (rocky shore and collector ropes) was cultivated on a raft (submerged culture) in the Ría de Arousa (north-west Spain) from approximately 20 mm to 60 mm shell length. Absorption efficiencies (AEs) and absorption rates (ARs) of the individuals were recorded in situ throughout cultivation time from November to July (1995–1996). Absorption efficiencies varied according to a multiple model that highlighted the significant effect of quality of natural seston (f as relative organic content), time of culture and origin of mussel seed. Initial AE values were 42 and 34% of the ingested organic material for collector ropes and rocky shore mussels (P<0.01), respectively. These differences remained significant for the first two months of the culture with higher values for collector ropes mussels. A significant relationship AE vs quality of natural seston (f) was observed according to an asymptotic equation: AE=0.82[1[minus sign]e−5.01(f−0.21)] for both sources of seed (r2=0.90). Absorption rate (mg organic matter g−1 h−1) followed a seasonal pattern with low values in winter and higher values in spring–summer as a consequence of better nutritional quality of food resources. Nevertheless, exceptional peaks of organic material from sedimentary origin in January caused an increase of ingested/absorbed organic material despite its low nutritional quality. Differences in AR values between origins of mussel seed referred to the first month under culture, with higher values for collector ropes individuals. Original habitat of mussel seed usually employed in mussel culture in Galicia is responsible for long-lasting effects through physiological changes that the individuals from the rocky shore habitat presented when placed under raft-submerged culture.
Asymmetry in the embryonic chromatophore pattern of the squid Loligo forbesi (Mollusca: Cephalopoda): a proxy for developmental instability
Authors: Gowland F.C. , Boyle P.R. , Noble L.R.
Published: September 2003

The effect of thermal stress upon pattern development in Loligo forbesi was investigated. Levels of pattern disruption and pattern asymmetry were measured by examining the chromatophores of hatchlings reared at three constant temperatures (8, 12 and 16°C). Results indicate a strong positive correlation between thermal stress and disruption of embryonic chromatophore pattern. Asymmetry in chromatophore pattern occurs non-directionally and can therefore be described as fluctuating asymmetry.
Patiriella pseudoexigua (Asteroidea: Asterinidae): a cryptic species complex revealed by molecular and embryological analyses
Authors: Hart Michael W. , Byrne Maria , Johnson Sheri L.
Published: September 2003

Cryptic lineages were identified within a morphologically uniform group of sea stars distributed from Australia to Japan. Among eight populations, all of which have been referred to Patiriella pseudoexigua, we found seven unique mitochondrial DNA sequences clustered into four distinct lineages. These four lineages formed a monophyletic group in which sister clades were separated by small genetic distances but could be differentiated from each other on the basis of reproductive differences. The four lineages thus appear to be separate but very closely related species. Examination of reproduction in several Queensland populations revealed that one population (Statue Bay) consisted of hermaphroditic intragonadal brooders with live-born offspring while other populations (Townsville, Bowen, Airlie Beach) consisted of dioecious free-spawners with a planktonic larva. The brooded larvae from central Queensland populations closely resembled brooded embryos and larvae of a Japanese lineage, while the planktonic larvae from northern Queensland were similar to the original description of planktonic larvae from a Taiwan population. However, each of the viviparous lineages was more closely related to a lineage with planktonic larval development than the viviparous lineages were to each other. Patiriella pseudoexigua thus comprises at least four species with different reproductive phenotypes in which viviparous brooding appears to have evolved in parallel. Based on previous taxonomic work we propose the following names for these four lineages: the dioecious free-spawner from northern Queensland (including the P. pseudoexigua type locality) is P. pseudoexiguasensu stricto; the viviparous brooder from central Queensland is undescribed and here referred to as Patiriella sp. nov; the dioecious free-spawner from Taiwan is temporarily referred to as Patiriella sp. (a senior name for this species may be P. pentagonus); and the hermaphrodite brooder from Japan should be raised to specific status and referred to by the new combination P. pacifica.
Ontogenetic changes in the feeding habits and dietary overlap between three abundant rajid species on the Falkland Islands' shelf
Authors: Brickle P. , Laptikhovsky V. , Pompert J. , Bishop A.
Published: September 2003

The ontogenetic changes in the diet and dietary overlap of three commercially important rajid species inhabiting the slope and shelf waters of the Falkland Islands were investigated. The white dotted skate (Bathyraja albomaculata) was a specialized amphipod and polychaete feeder. The broad nose skate (B. brachyurops) had a diverse diet, consuming a wide variety of crustaceans and fish. The grey tail skate (B. griseocauda) also had a broad diet but consumed a high proportion of amphipods and isopods (e.g. Serolis spp.). Larger individuals of the latter species were more piscivorous and consumed more squid. The diets of all three species showed a marked variation with ontogeny. Dietary overlap was greatest for smaller animals (<30 cm disk width), after which each species became more specialized in their diets. Smaller animals also showed some differences in depth of distribution, which may be an adaptation to reduce inter-specific competition.
Embryonic and larval development of Gobius paganellus (Pisces: Gobiidae)
Authors: Borges Rita , Faria Cláudia , Gil Fátima , Gonçalves Emanuel J. , Almada Vitor C.
Published: September 2003

The full developmental sequence from egg to juvenile of Gobius paganellus under controlled conditions is described. Embryonic development lasted 9–10 days at 18.5–20.0°C and 10–11 days at 15.0–16.5°C. Newly hatched larvae measured 3.90 mm, had the mouth and anus opened, pigmented eyes and almost no yolk. They first settled 25 days after hatching (10.0–10.5 mm total length [TL]) and showed juvenile behaviour and body form 36 days after hatching (14.0 mm TL). However, they only showed full juvenile pigmentation patterns 15 days later (17.0 mm TL) (16.0–16.5°C). In addition, a preliminary differentiation between the newly hatched larvae of the most common Gobius species of south-western European shores is presented.
Views across Borders
Authors: Edgar David
Published: September 2003

Early on in the first Thatcher term, one of her young Turk backbenchers announced
that his mission in life was to eliminate all small touring theatre companies with the
word ‘red’ in their title. In doing so, he acknowledged that in the
'seventies oppositional theatre had ceased to be constrained within theatre
buildings (in the mid-'sixties, he'd have wanted to abolish all
companies called ‘English’ working in theatres called ‘Court’).
Cheerful History: the Political Theatre of John McGrath
Authors: Milne Drew
Published: September 2003

In this essay, Drew Milne suggests affinities between the dramatization of history in
the work of John McGrath and Karl Marx. He shows how both Marx and McGrath refused to mourn
the histories of Germany and Scotland as tragedies, but that differences emerge in the
politics of McGrath's radical populism – differences apparent in McGrath's use of music, historical quotation, and direct address. McGrath's layered theatricality engages audience sympathies in ways that emphasize awkward parallels between modern and pre-modern Scotland, and this can lead to unreconciled tensions between nationalism and socialism which are constitutive of McGrath's plays. Drew Milne is the Judith E. Wilson Lecturer in Drama and Poetry, Faculty of English, University of Cambridge, and a Fellow of Trinity Hall. He has published various articles on drama and performance, including essays on the work of August Boal, Samuel Beckett, and Harold Pinter, and is currently completing a book entitled Performance Criticism.
Finite Resources, Infinite Dedication: Shakespeare at the Tobacco Factory
Authors: Brandt George
Published: September 2003

Does the prevailing approach to performing Shakespeare, which increasingly reflects nothing more than directorial quirks consuming more cash than creative energy, threaten to cast us adrift from the plays? Those who think so have been strengthened in their belief by a surprisingly inexpensive venture operating in Bristol since the year 2000, under the title ‘Shakespeare at the Tobacco Factory’. This company have been working in an industrial setting with a minimal production and publicity budget but intense dedication to close textual reading, and have been quick to attract national attention with their pared-down presentations. Professor Emeritus George Brandt, who describes the origins and aims of this group, has been observing the local theatrical scene since 1951, when he joined the Drama Department of the University of Bristol. In his 35 years on its staff, during which he served as its Head of Department over a number of years, he shaped much of its policy, creating among other things the first practical postgraduate film course at a British university. George Brandt edited British Television Drama (1981) and British Television Drama in the 1980s (1993) for Cambridge University Press. His German and Dutch Theatre, 1600–1848 (1993), with Professor Hogendoorn, was part of the CUP series ‘Theatre in Europe’. His Modern Theories of Drama was published by Oxford University Press in 1998. He is currently a Senior Research Fellow of the University of Bristol.
Plugged into History
Authors: Bradby David , Capon Susan
Published: September 2003

Report on the conference to celebrate and interrogate John McGrath's work held at Royal Holloway, University of London, on 19–20 April 2002.
Masks in the Ancient and Modern Theatre
Authors: Coldiron Margaret
Published: September 2003

Report of the conference on ‘The Greek Theatre Mask in Ancient and Modern Performance’, held at the Noh Studio at Royal Holloway, University of London, on 20–21 April 2002.
The use of riparian environments in the rural Peruvian Amazon
Authors: McClain Michael E. , Cossío Rosa E.
Published: September 2003

River margins are valued for agriculture in the western Amazon because of their fertile soils and level surfaces. Riparian forests along river margins also provide valuable ecosystem services by protecting water quality and providing resources to aquatic organisms. Because inhabitants of the region rely on these aquatic resources, riparian deforestation may have unintended negative feedbacks on the health and well-being of rural communities. A survey of 79 households of mixed cultural background investigated how riparian environments were used, what mechanisms were in place for their conservation, and how local people valued them. Corn, beans and peanuts were cultivated preferentially in riparian areas, complementing the manioc and plantains grown on upland soils. People valued riparian areas for their ecosystem services and generally left a protective buffer of forest along rivers. Both the agricultural and ecological values of riparian areas may be preserved through proper management.
Air quality standard exceedance and management in an Indian mining area
Authors: Chaulya S.K.
Published: September 2003

Detailed studies are essential in India to evaluate air quality and implement measures for effective control of mining in sensitive locations. A study for this purpose was carried out in the Basundhara area of the Ib Valley coalfield in Orissa State, India. The 24-hr average concentrations of suspended particulate matter (SPM), respirable particulate matter (RPM), sulphur dioxide (SO2) and oxides of nitrogen (NOx) were determined at regular intervals throughout one year at seven monitoring stations in residential areas and two stations in mining/industrial areas. The 24-hr average SPM and RPM concentrations were 312.7–598.4 μg m−3 and 100.2–199.6 μg m−3 in industrial areas, and were 95.6–275.7 μg m−3 and 28.5–86.8 μg m−3 in residential areas. During the study period, 24-hr and annual average SPM and RPM concentrations exceeded the respective standards set in the Indian national ambient air quality standard (NAAQS) protocol in certain residential and industrial areas. However, 24-hr and annual average concentrations of SO2 (residential: 20.5–24.3 μg m−3, industrial: 15.3–30.8 μg m−3) and NOx (residential: 19.7–25.3 μg m−3, industrial: 14.3–33.5 μg m−3) were well within the prescribed limit of the NAAQS in both residential and industrial areas. The temporal variations of SPM and RPM fitted polynomial trends well and on average in the mining area 31.38% of the SPM was RPM. The linear regression correlation coefficients between SPM and RPM and between NOx and SO2 were 0.90 and 0.52, respectively. The kriging technique determined that maximal concentrations of SPM and RPM occurred within the mining site. A management strategy is formulated for effective control of air pollution at source, and mitigative measures should include implementation of green belts around the sensitive areas where the concentration of air pollutants exceeds the standard limit.
Upgrading municipal environmental services to European Union levels: a case study of household willingness to pay in Lithuania
Authors: Bluffstone Randall , DeShazo J.R.
Published: September 2003

Lithuania is one of ten countries in Central and Eastern Europe that is aligning its environmental policies with those of the European Union (EU). The costs of harmonizing environmental policies are expected to be extremely high and to fall disproportionately on local governments. One policy option for financing these service upgrades is to use increased tariffs. We evaluate the feasibility of this strategy by estimating household willingness to pay for upgraded landfill, sewerage, and recycling programs. We then compare estimated benefits with costs from the literature. We find that household willingness to pay is substantial for upgraded landfill management and expanded sewerage service, but virtually zero for the two recycling programs considered. Relative to costs, households are willing to pay approximately 80–90 per cent of costs for landfill improvement, but less than 10 per cent for upgraded sewerage service and recycling programs. These results suggest that targeted subsidies will be critical to fund the municipal environmental expenditures required for Lithuania to join the EU.
Gene expression in HCV‐associated hepatocellular carcinoma – upregulation of a gene encoding a protein related to the ubiquitin‐conjugating enzyme
Authors: El‐Nady Ghada M. , Ling Roger , Harrison Tim J.
Published: September 2003

Background/Aim: To investigate gene expression in HCV‐associated human hepatocellular carcinomas (HCC) by identifying up‐ and down‐regulated genes.

Methods:  Differential display RT‐PCR was used to compare levels of gene expression in tumorous and non‐tumorous tissues from the same livers. Differential expression was confirmed using a ribonuclease protection assay (RPA). The relative expression levels of one candidate gene were studied in various normal tissues and malignant cell lines using a multiple tissue expression (MTE) array. Further characterisation of this gene was carried out using nucleotide sequence analysis programmes and Northern hybridisation.

Results:  Fifty‐two differentially expressed cDNA fragments were identified and 29 were cloned, sequenced and compared with the nucleotide sequence database. RPA confirmed reproducibly that one particular cDNA was upregulated in the tumour cells. Analysis using the MTE array revealed that this selected candidate gene is expressed at high levels in various human tumour cell lines. The expression levels in HCV‐associated HCC were higher than in other tumours. Investigation revealed that this novel gene lies on chromosome 17. The transcript is approximately 2.5 kb in size and encodes a protein similar to the ubiquitin‐conjugating enzyme.

Conclusions:  The ubiquitin system may be involved in HCV‐related hepatocarcinogenesis and in the development of other cancers.
Spatial and temporal woodland patterns along the lower Turkwel River, Kenya
Authors: Stave Jørn , Oba Gufu , Bjorå Charlotte S. , Mengistu Zelalem , Nordal Inger , Stenseth Nils C.
Published: September 2003

Spatial and temporal patterns of riverine woodlands in arid regions of Africa are poorly documented despite their considerable conservation value. We studied 1540 ha of riverine woodland in the lower Turkwel River floodplain, Kenya, between 1990 and 1998. Forty‐one woodland patches were mapped and their soil physical and chemical characteristics, tree species diversity, woody cover, tree density, wood volume and woodland regeneration were determined. The riverine woodland comprised nine vegetation types and a total of 14 woody species. Woodland patch mosaics were associated with microtopographical features and selected soil attributes. The most important woody species were Hyphaene compressa H. Wendl., Acacia tortilis (Forssk.) Hayne and Cadaba rotundifolia Forssk. The exotic Prosopis chilensis (Mol.) St. was invading parts of the riverine woodland. Overall, woody species diversity was low compared to similar riverine woodlands in East Africa. Tree density, wood volume and woody plant regeneration declined over the 8‐year study period, while woody cover was unchanged. Reduced tree density, wood volume and regeneration of woody species might be linked to changes in river flood patterns following the impoundment of the Turkwel Gorge Dam. It is suggested that spatially heterogeneous and temporally stochastic regeneration events, together with occasional tree mortality caused by channel abandonment, create the complex pattern of woodland patches in the lower Turkwel River floodplain. The mapped woodland patches may serve as monitoring units, which in future could reveal the interplay between changes in flooding patterns as a result of dam impoundment, anthropogenic disturbance and the well‐being of the riverine woodlands.
Towards a density measure for assessments of arid plant populations – examples from the southern Namib Desert
Authors: Burke Antje , Mannheimer Coleen
Published: September 2003

Plant species in arid environments are often widely spaced making population assessments difficult. In order to minimise observer bias we tested two repeatable simple methods during red data assessments in the southern Namib Desert. Both the transect‐based and the quadrat‐based method resulted in over‐estimates of the true population size. However, because of case of application, the transect method warrants further development.
Microbial dolomite crusts from the carbonate platform off western India
Authors: Rao V. Purnachandra , Kessarkar Pratima M. , Krumbein W. E. , Krajewski K. P. , Schneider Robert J.
Published: September 2003

AbstractThe occurrence of Late Pleistocene dolomite crusts that occur at 64 m depth on the carbonate platform off western India is documented. Dolomite is the most predominant mineral in the crusts. In thin section, the crust consists of dolomitized microlaminae interspersed with detrital particles. Under scanning electron microscopy, these laminae are made up of tubular filaments or cellular structures of probable cyanobacterial origin. Dolomite crystals encrust or overgrow the surfaces of the microbial filaments and/or cells; progressive mineralization obliterates their morphology. Well‐preserved microbial mats, sulphide minerals (pyrrhotite and marcasite) and the stable isotope composition of dolomite in the crusts indicate hypersaline and anoxic conditions during dolomite formation. The crusts are similar to dolomite stromatolites, and biogeochemical processes related to decaying microbial mats under anoxic conditions probably played an important role in dolomite precipitation. The dolomite is therefore primary and/or very early diagenetic in origin. The dolomite crusts are interpreted to be a composite of microbial dolomite overprinted by early burial organic dolomite. The results of this study suggest that a microbial model for dolomite formation may be relevant for the origin of ancient massive dolomites in marine successions characterized by cryptalgal laminites. The age of the crusts further suggests that the platform was situated at shallow subtidal depths during the Last Glacial Maximum.
Carbonate platform growth influenced by contemporaneous basaltic intrusion (Albian of Larrano, Spain)
Authors: Fernández‐Mendiola Pedro A. , GarcÌa‐MondÈjar JoaquÌn
Published: September 2003

Abstract Carbonate platform growth in active tectonic settings may be strongly influenced by the structural evolution of the basin, including volcanic activity. In this paper, the sedimentary–tectonic evolution of the Duranguesado carbonate platform (Larrano) in northern Spain is described, and an evolutionary depositional model is presented. The Albian Duranguesado carbonate platform deposits are dominated by rudist and coral limestones with small intervening argillaceous limestone‐filled troughs (10–30 m deep). The platform succession is divided into two parts. The lower platform deposits were intruded by volcanics and tilted before the deposition of the upper platform succession. A volcanic vent plug filling an upward‐flaring pipe occurs in the lower carbonate platform succession. The timing of intrusion is well constrained to the early Albian. Tectonic extension and active deep‐seated strike‐slip faults induced magma ascent at a fault intersection. Sedimentological analysis of these areas indicates that, before volcanic intrusion, they acted as weakened zones of extension, and were slightly more subsident basinal areas. These sites contain anomalous accumulations of siliceous sponge spicule deposits, linked to the release of hydrothermal fluids on the sea floor. After the phase of intrusion, tilting and erosion of the platform and its associated volcanic products occurred. As the intrusion cooled, the platform downwarped, leading to the formation of an overlying perched capping basin bordered by carbonate platforms. Over the volcanic plug, carbonate mounds grew on local palaeohighs. The presence of strike‐slip and magma emplacement in the Duranguesado platform is related to movements between the Iberian and European lithospheric plates, which were accommodated by rotation and lateral movement of the crust along wrench faults.
Effect of dietary oregano oil and α‐tocopheryl acetate supplementation on iron‐induced lipid oxidation of turkey breast, thigh, liver and heart tissues
Authors: Papageorgiou G. , Botsoglou N. , Govaris A. , Giannenas I. , Iliadis S. , Botsoglou E.
Published: September 2003

Twenty‐five 12‐week‐old turkeys randomly divided into five groups were given a basal diet, or a basal diet supplemented with 200 mg α‐tocopheryl acetate/kg, or 100 mg oregano oil/kg or 200 mg oregano oil/kg, or 100 mg oregano oil plus 100 mg α‐tocopheryl acetate/kg diet, for 4 weeks prior to slaughter. Breast, thigh, liver and heart tissues were subjected to iron‐induced lipid oxidation, the extent of which was determined by third‐order derivative spectrophotometry. Results showed that dietary oregano oil at the inclusion level of 200 mg oregano oil/kg diet was more effective in delaying lipid oxidation compared with the inclusion level of 100 mg/kg, but equivalent to the inclusion of 200 mg α‐tocopheryl acetate/kg diet, which in turn was inferior to the combined inclusion of 100 mg oregano oil plus 100 mg α‐tocopheryl acetate/kg, which was superior to all dietary treatments. Thigh tissue was more susceptible to oxidation than breast tissue, although it contained α‐tocopherol at higher concentrations. Also, lipid oxidation in heart was relatively high, although it contained the highest α‐tocopherol levels. This indicates that tissue α‐tocopherol is one important factor influencing the level of lipid oxidation, but the distribution of lipids, iron and oregano oil in tissues must also be taken into consideration. Tissue α‐tocopherol levels responded to dietary intake of 30–200 mg α‐tocopheryl acetate/kg in the order heart > liver > thigh > breast. Breast, thigh and heart tissues from the oregano groups presented significantly (p < 0.05) higher levels of α‐tocopherol compared with the control, the increase being positively correlated with the supplementation level. The increased levels of α‐tocopherol in these tissues indicated that the dietary oregano oil exerted a protective action on α‐tocopherol.
Tryptophan requirement of growing pigs at various body weights
Authors: Eder K. , Nonn H. , Kluge H. , Peganova S.
Published: September 2003

The purpose of this study was to determine the tryptophan (Trp) requirement of growing pigs at different body weight (BW) ranges. Three performance experiments were conducted with female pigs in the BW ranges of 25–50, 50–80 and 80–115 kg. In addition to the performance experiments, nitrogen balance experiments were carried out in which pigs weighing 56, 66 and 86 kg were used. Trp‐deficient basal diets were formulated to which varying amounts of l‐Trp were added. The amino acid concentrations of the diets were analysed; concentrations of standardized digestible amino acids were calculated on the basis of tabular values. The calculated concentrations of standardized ileal digestible tryptophan were 0.81, 1.11, 1.41, 1.71, 2.01 g/kg diet in the lower BW range (25–50 kg), 0.71, 0.96, 1.21, 1.46, 1.71 g/kg diet in the middle BW range (50–80 kg), and 0.49, 0.69, 0.89, 1.09, 1.29 g/kg diet in the upper BW range (80–115 kg). Dose–response relationships were evaluated by means of an exponential regression model. In all three age ranges, performance parameters as well as nitrogen retention were strongly influenced by the dietary concentration of standardized ileal digestible tryptophan. According to the exponential model, in the 25–50 kg BW range, 95% of the maximum feed consumption, BW gain and nitrogen retention were achieved at concentrations between 1.96 and 2.00 g of standardized ileal digestible Trp per kilogram diet, corresponding to 3.32–3.39 g/day. In the BW range of 50–80 kg, 95% of the maximum of these parameters occurred at concentrations of standardized ileal digestible tryptophan in excess of the highest concentration of 1.71 g/kg diet, corresponding to 3.71 g/day. In the BW range of 80–115 kg, 95% of the maximum of BW gain and nitrogen retention were recorded at concentrations of 1.22 and 0.84 g standardized ileal digestible Trp per kilogram diet, corresponding to 3.77 and 2.25 g/day, respectively. Related to the energy value of the diets, the optimal concentration of standardized ileal digestible tryptophan are between 140 and 143 mg/MJ metabolizable energy (ME) in the BW range of 25–50 kg, in excess of 127 mg/MJ ME in the BW range of 50–80 kg and between 62 and 90 mg/MJ ME in the BW range of 80–115 kg. In conclusion, it is suggested that the requirement of standardized ileal digestible tryptophan for growing pigs might be higher than currently assumed.
Expression of the Major Outer Membrane Protein (MOMP) of Chlamydophila abortus, Chlamydophila pecorum, and Chlamydia suis in Escherichia coli using an Arabinose‐inducible Plasmid Vector
Authors: Hoelzle L. E. , Hoelzle K. , Wittenbrink M. M.
Published: September 2003

The ompA genes encoding the 40 kDa major outer membrane protein (MOMP) of Chlamydophila (Ch.) abortus, Ch. pecorum, and Chlamydia (C.) suis were cloned into the arabinose‐inducible plasmid vector pBADMycHis, and recombinant MOMPs (rMOMP) from the three chlamydial species were expressed at high levels in Escherichia (E.) coli. The proteins lacking the 22 aa N‐terminal signal peptide were expressed as insoluble cytoplasmic inclusion bodies which were readily purified using immobilized metal‐affinity chromatography. The rMOMPs including the N‐terminal signal peptide were expressed and translocated as a surface‐exposed immunoaccessible protein into the outer membrane of E. coli. Transformants expressing this full‐length rMOMP were significantly reduced in viability. Purified native elementary bodies (EB) and rMOMPs of the three chlamydial species purified from the E. coli cytoplasm were used for immunization of rabbits. The resulting sera were analysed for their ability to recognize homologous and heterologous rMOMP and native EB. When testing rMOMP antisera against rMOMP and EB antigens, marked cross‐reactivities were detected between the three species. Using EB antisera and rMOMPs as antigens, a significant species‐specific reactivity was measured.
The Effect of Kefir on the Activities of GSH‐Px, GST, CAT, GSH and LPO Levels in Carbon Tetrachloride‐Induced Mice Tissues
Authors: Güven A. , Güven A. , Gülmez M.
Published: September 2003

Functional foods including kefir have increasingly become as popular as before in the developing world. The health benefits of kefir including the antioxidative effects are still under evaluation. Vitamin E is also a well‐known antioxidant. The biologically damaging effects of reactive oxygen species are controlled in vivo by a wide spectrum of antioxidant defence mechanisms. Dietary constituents of antioxidative vitamins and other nutrients may play an important role in protecting the body against oxidative damage. The study was carried out to investigate the protective effect of kefir against oxidative damage of CCl4 in mice, compared with the well‐known antioxidant vitamin E. Three‐week‐old Swiss Albino mice, weighing 22–26 g were used for the experiment. At the end of the microbiological analysis of kefir, the averages of the total mesophilic aerobic colony counts, lactic acid bacteria, lactic streptococci, enterococci, and yeasts were found to be 1.04 × 109, 9.87 × 108, 4.38 × 108, 7.80 × 104 and 1.26 × 105 CFU/ml, respectively. While both vitamin E and kefir were found to have a protective effect aganist CCl4‐induced damage, kefir was more protective. This may probably be the first study to compare the antioxidative action of kefir and vitamin E in the animal model.
Herd Management Practices Associated with Paratuberculosis Seroprevalence in Dutch Dairy Herds
Authors: Muskens J. , Elbers A. R. W. , Van Weering H. J. , Noordhuizen J. P. T. M.
Published: September 2003

We describe the paratuberculosis management practices applied in dairy herds in the Netherlands. The findings from paratuberculosis seronegative and seropositive herds were compared to discover possible risk factors. In total, 370 randomly selected herds with ≥20 dairy cows were surveyed. A questionnaire was used to collect data on current and previous paratuberculosis management practices. All cattle aged ≥3 years were serologically tested for paratuberculosis using an enzyme‐linked immunosorbent assay. Herds with >33 tested cattle, of which only one was seropositive, were excluded to reduce the risk of including false‐positive herds in the analysis. A comparison of the management data of the seronegative herds (n = 166) and the seropositive herds (n = 143) showed that in both groups important management measures for the prevention of paratuberculosis, such as calving in a cleaned calving area, removing the calf immediately after birth, and feeding paratuberculosis non‐suspect roughage to calves, were used only rarely. However, such measures should be regarded as the critical first step to control the disease and/or reduce its prevalence. Using univariable analysis, four factors were statistically different between seronegative and seropositive herds: herd size, cows with clinical signs of paratuberculosis, prompt selling of clinically diseased cattle and feeding milk replacer. Using a multivariable logistic regression model, only herd size was a significantly different factor. These results indicate that most of the paratuberculosis preventive management measures were executed on these Dutch dairy farms only to a limited extent.
Expression and plasticity of galanin systems in cortical neurons, oligodendrocyte progenitors and proliferative zones in normal brain and after spreading depression
Authors: Shen Pei‐Juan , Larm Jari A. , Gundlach Andrew L.
Published: September 2003

Neocortex contains very few galanin neurons but receives a moderate galanin innervation from various subcortical loci. Recent data suggest that galanin helps regulate the tonic neuronal excitability of hippocampus and probably cerebral cortex but relatively little is known about the anatomy and functional regulation of cortical galanin systems. Therefore, we examined, in the rat, the effect of the intense but benign stimulus, cortical spreading depression (CSD), on the expression of galanin and galanin receptors (GalR1 and GalR2) in the neocortex and associated regions, revealing complex, multicellular responses. Thus, following acute, unilateral KCl‐induced CSD, a delayed and transient induction (onset after 48 h, lasting ∼24 h) of galanin mRNA and peptide production occurred across the ipsilateral cerebral cortex in activated oligodendrocyte progenitor cells (OPCs), identified by specific NG2 proteoglycan immunostaining. An increase in GalR1 mRNA, immunoreactivity and receptor binding occurred in neurons within layers II and V of neocortex and in piriform cortex at 7–28 days after CSD, associated with a long‐lasting depletion of galanin‐positive nerve fibres in these regions. In contrast, GalR2 mRNA expression was largely unaltered after CSD. Additional novel findings in normal, adult brain were the detection of galanin mRNA and immunoreactivity in OPCs within the medial corpus callosum and in immature progenitor cells in the subventricular zone and rostral migratory stream. GalR1 and GalR2 mRNA was also present in these latter regions. These findings and the complex modulation of galanin and galanin receptors in multiple cell types (neurons/OPCs) following acute cortical activation/depression further demonstrate the potential plasticity of neuronal and non‐neuronal galanin systems under physiological and pathological conditions and strongly suggest additional functions for this pleiotropic peptide in mammalian brain.
Depolarization differentially affects the secretory and migratory properties of two cell lines of immortalized luteinizing hormone‐releasing hormone (LHRH) neurons
Authors: Pimpinelli Federica , Redaelli Elisa , Restano‐Cassulini Rita , Curia Giulia , Giacobini Paolo , Cariboni Anna , Wanke Enzo , Bondiolotti Gian Pietro , Piva Flavio , Maggi Roberto
Published: September 2003

In this report we studied and compared the biochemical and the electrophysiological characteristics of two cell lines (GT1‐7 and GN11) of immortalized mouse LHRH‐expressing neurons and the correlation with their maturational stage and migratory activity. In fact, previous results indicated that GN11, but not GT1‐7, cells exhibit an elevated motility in vitro. The results show that the two cell lines differ in terms of immunoreactivity for tyrosine hydroxylase and nestin as well as of production and release of 3,4‐dihydroxyphenylalanine (DOPA) and of intracellular distribution and release of the LHRH. Patch‐clamp recordings in GN11 cells, reveal the presence of a single inward rectifier K+ current indicative of an immature neuronal phenotype (neither firing nor electrical activity). In contrast, as known from previous studies, GT1‐7 cells show the characteristics of mature LHRH neurons with a high electrical activity characterized by spontaneous firing and excitatory postsynaptic potentials. K+‐induced depolarization induces in GT1‐7 cells, but not in GN11 cells, a strong increase in the release of LHRH in the culture medium. However, depolarization of GN11 cells significantly decreases their chemomigratory response. In conclusion, these results indicate that GT1‐7 and GN11 cells show different biochemical and electrophysiological characteristics and are representative of mature and immature LHRH neurons, respectively. The early stage of maturation of GN11 cells, as well as the low electrical activity detected in these cells, appears to correlate with their migratory activity in vitro.
GABAergic control of neuropeptide gene expression in parvocellular neurons of the hypothalamic paraventricular nucleus
Authors: Bali Balázs , Kovács Krisztina J.
Published: September 2003

To assess the functional impact of local inhibitory γ‐aminobutyric acid (GABA)ergic interneuron population on the cellular and transcriptional activity of parvocellular neurosecretory neurons in the hypothalamic paraventricular nucleus (PVH), we followed the expression of corticotropin‐releasing hormone (CRH) and arginine vasopressin (AVP) genes along with the activation marker c‐fos in response to the blockade of GABA‐A receptors. First, we analysed the effect of the GABA‐A receptor antagonist bicuculline methiodide (BMI) in organotypic cultures of hypothalamic slices. These preparations preserve the cytoarchitecture of CRH‐synthesizing cell populations and elements of local interneuronal networks, while remote connections originating from limbic‐ and brainstem areas are missing. In vitro, BMI resulted in a selective induction of c‐Fos immunoreactivity that was localized exclusively to the PVH and upregulated both CRH mRNA and AVP hnRNA levels. Local microinjection of BMI into the paraventricular region of freely moving rats increased the adrenocorticotropin secretion and activated PVH neurons ipsilateral to the injection. c‐Fos immunoreactivity was distributed within the PVH and in the perinuclear region, where it appeared in GABAergic and also in non‐GABAergic profiles. This treatment induced AVP hnRNA expression in the parvocellular compartment without any reliable stimulation of CRH transcription in the parvocellular‐ and AVP hnRNA levels in the magnocellular neurons. These results reveal an intrinsic GABAergic mechanism in the PVH microenvironment that by itself, without limbic contribution, impinges a tonic inhibitory influence on the parvocellular CRH neurons in vitro. In vivo, remote inputs are superimposed on the local circuit, allowing differential transcriptional regulation of CRH and AVP genes in the hypophyseotropic neurons.
Homer1 proteins and AMPA receptors modulate cocaine‐induced behavioural plasticity
Authors: Ghasemzadeh M. Behnam , Permenter Lindsay K. , Lake Russell , Worley Paul F. , Kalivas Peter W.
Published: September 2003

Homer proteins form functional assemblies in the excitatory postsynaptic density, and withdrawal from repeated cocaine administration reduces the expression of Homer1b/c in the nucleus accumbens. To determine if the reduction in Homer1b/c may be contributing to cocaine‐induced behavioural sensitization, antisense oligonucleotides were infused over two weeks into the nucleus accumbens of rats to reduce Homer1 gene expression by approximately 35%. Infusion of antisense sequences (AS1 and AS2) caused a sensitization‐like augmentation in the motor response to acute cocaine administration in naive rats. One of the sequences (AS1) also prevented the development of sensitization to repeated cocaine treatment, while AS2 was without effect. A panel of immunoblots for other proteins in the excitatory postsynaptic density revealed that AS1, but not AS2 reduced the level of the α‐amino‐3‐hydroxy‐5‐methylisoxazole‐4‐propionic acid (AMPA) receptor subunit GluR1 protein. This posed the possibility that altered AMPA signalling may mediate the inhibitory effect of AS1 on the development of sensitization. To examine this possibility, rats were pretreated in the accumbens with drugs to block AMPA/kainate, N‐methyl‐d‐aspartate, group 1 metabotropic glutamate or dopamine receptors prior to each daily injection of cocaine. Only AMPA/kainate receptor blockade prevented the development of behavioural sensitization to cocaine. These data indicate that the expression of behavioural sensitization arises in part from a reduction in Homer1 gene products in the accumbens, while the development of sensitization requires stimulation of AMPA/kainate receptors.
Bicuculline induces synapse formation on primary cultured accessory olfactory bulb neurons
Authors: Kato‐Negishi Midori , Muramoto Kazuyo , Kawahara Masahiro , Hosoda Ritsuko , Kuroda Yoichiro , Ichikawa Masumi
Published: September 2003

To investigate the roles of the GABAergic inhibitory system of accessory olfactory bulb (AOB) in pheromonal memory formation, we have developed a primary culture system of AOB neurons, which had numerous excitatory and inhibitory synapses. Using this culture system of AOB neurons, we examined the correlation in rats between neuronal excitation and synaptic morphology by bicuculline‐induced disinhibition of cultured AOB neurons. The exposure to bicuculline induced long‐lasting oscillatory changes in the intracellular calcium level ([Ca2+]in) of cultured non‐GABAergic multipolar neurons, which were identified as mitral/tufted cells (MT cells). These MT cells exhibited the appearance of dendritic filopodia structures after a 10‐min treatment with bicuculline. By labelling presynaptic terminals with FM4‐64, the appearance of new presynaptic terminals was clearly observed on newly formed filopodia after 120 min treatment with bicuculline. These results suggest that bicuculline‐induced [Ca2+]in oscillation of MT cells induces the growth of filopodia and subsequently the formation of new presynaptic terminals. Furthermore, tetrodotoxin or the deprivation of extracellular calcium blocked bicuculline‐induced synapse formation. The present results indicate that the long‐lasting [Ca2+]in oscillation caused by bicuculline‐induced disinhibition of cultured MT cells is significantly implicated in the mechanism underlying synapse formation on cultured AOB neurons. Our established culture system of AOB neurons will aid in clarifying the mechanism of synapse formation between AOB neurons and the molecular mechanism of pheromonal memory formation.
Seizure‐free Days Observed in Randomized Placebo‐controlled Add‐on Trials with Levetiracetam in Partial Epilepsy
Authors: Leppik Ilo , Morrell Martha , Godfroid Philippe , Arrigo Celestina
Published: September 2003

Summary:  Purpose: We examined the effect of adjunctive levetiracetam (LEV; 1,000 to 3,000 mg/day) on the number of seizure‐free days gained per quarter in adult patients with refractory partial‐onset epilepsy.

Methods: The treatment effect was studied in a meta‐analysis using individual patient data of a subpopulation of patients (n = 846) emerging from the three randomized, double‐blind, placebo‐controlled, phase III trials (n = 904).

Results: Adding LEV effectively increased the number of days without seizures by 5.19 days per quarter [95% confidence interval (CI), 3.63–6.76; p = 0.0001; titration and stable dose periods].

Conclusions: LEV adjunctive treatment shows a clear benefit in terms of seizure‐free days gained for patients with refractory epilepsy. This gain is significant for the pooled and for each LEV dose compared with placebo.
Wage differentials and state‐private sector employment choice in Yugoslavia*
Authors: Lokshin Michael M. , Jovanovic Branko
Published: September 2003

In this study we use the newly available Yugoslavian Labor Force Survey data to investigate wage differentials and employment decisions in the state and private sectors in Yugoslavia. For the analysis we use three empirical models that rely on different statistical assumptions. We extend the standard switching regression model to allow non‐normality in the joint distribution of the error terms. After correcting for the sector selection bias and controlling for workers’ characteristics we find a private sector wage advantage. The wage premium is largest for workers with low education levels and declining for workers with higher educational levels. Given the regulatory and tax policies that pushed the private sector into the informal sphere of the economy during the period covered by our data, we argue that the state/private wage gap is likely to grow in the future. This will make it increasingly difficult for the state sector to attract and retain highly skilled employees.