bluuebunny/crossref_metadata_2025 huggingface dataset:
Consistency of patterns between laboratory experiments and field collected fish in otolith chemistry: an example and applications for salinity reconstructions
Authors: Elsdon T. S. , Gillanders B. M.
Published: July 2005

Elemental concentrations within fish otoliths can track movements and migrations of fish through gradients of environmental variables. Tracking the movements of fish relies on establishing links between environmental variables and otolith chemistry, with links commonly made using laboratory experiments that rear juvenile fish. However, laboratory experiments done on juvenile fish may not accurately reflect changes in wild fish, particularly adults. We tested the hypotheses that: (1) the relationship between ambient (water) and otolith chemistry is similar between laboratory-reared black bream (Acanthopagrus butcheri) and wild black bream; and (2) ontogeny does not influence otolith chemistry. Field-collected and laboratory-reared fish showed similar effects of ambient strontium : calcium (Sr : Ca) on otolith Sr : Ca concentrations. However, ambient and otolith barium : calcium concentrations (Ba : Ca) differed slightly between laboratory-reared and field-collected fish. Importantly, fish reared in stable environmental variables showed no influence of ontogeny on Sr : Ca or Ba : Ca concentrations. Natural distributions of ambient Sr : Ca showed no clear relationship to salinity, yet, ambient Ba : Ca was inversely related to salinity. The distribution of ambient Sr : Ca and Ba : Ca in estuaries inhabited by black bream, suggest that these elements can answer different questions regarding environmental histories of fish. Reconstructing salinity histories of black bream using otolith Ba : Ca concentrations seems plausible, if adequate knowledge of Ba : Ca gradients within estuaries is obtained.
Seasonality in the deep sea and tropics revisited: what can otoliths tell us?
Authors: Morales-Nin Beatriz , Panfili Jacques
Published: July 2005

The accepted idea that fish otoliths from supposedly aseasonal environments, such as the deep sea and tropics, do not present seasonal growth increments is questioned and re-evaluated. The main seasonal fluctuation in deep seas is a result of the transfer of organic material from the productive upper layers to the abyssal depths. There is some evidence for seasonal patterns of otolith growth, although the validation of seasonal structures is limited owing to the difficulties inherent in deep-water studies. Tropical regions have an extremely high diversity of aquatic environments but in fact very few are aseasonal, and almost all areas have strong hydrological seasons, mainly annual, interacting with temperature variations. These climatic fluctuations have undoubtedly an effect on otolith growth, therefore leading to a succession of different incremental zones. The lack of previous knowledge on this impact of seasonality is probably a result of the previous low level of exploitation or economic interest of target species, and consequently the absence of age-based assessments. This trend has now changed possibly as a result of the increased exploitation of the resources, and to the greater involvement of international and national fishery management bodies. The number of studies showing apparent or validated seasonal marks has recently increased for these environments.
Age-related trends in otolith chemistry of Merluccius merluccius from the north-eastern Atlantic Ocean and the western Mediterranean Sea
Authors: Morales-Nin B. , Swan S. C. , Gordon J. D. M. , Palmer M. , Geffen A. J. , Shimmield T. , Sawyer T.
Published: July 2005

Sagittal otoliths of European hake obtained from five geographic locations in the north-eastern Atlantic and western Mediterranean were examined using laser ablation and inductively coupled plasma mass spectrometry. Otolith sections were analysed for the isotopes 24Mg, 55Mn, 66Zn, 85Rb, 86Sr, 138Ba and 208Pb, measured relative to 43Ca counts. These analyses considered only age 0 (core area) and ages 1 to 3. Age-related trends in otolith elemental composition were observed in hake from all areas, but were masked by variability between locations. Elemental concentrations generally decreased outside the core, with some increase at age 3. The composition of the otolith core was very distinct from that of the other growth increments. In the Mediterranean, part of this differentiation was a result of Mn, which was present in the core at high concentrations compared with the rest of the otolith. Mediterranean otoliths also had higher concentrations of Sr, Zn and Ba in the core. For most samples a similar trend was observed, although samples from one of the Mediterranean areas showed some differences, mainly in the concentrations of Mg and Sr. These results provide new empirical evidence of the variation in elemental concentrations across hake otoliths with age, at least throughout the first 3 years of life.
Estimating age composition using the Fredholm first-kind equation
Authors: Troynikov V. S. , Robertson S. G.
Published: July 2005

Estimation of age composition was considered in the context of non-parametric mixture distribution problems. The problem was formulated as a Fredholm first-kind equation with respect to the distribution function of age. The solution of the equation was obtained using methods for ‘ill-posed problems’. The approach is able utilise single and multi-dimensional empirical distributions of age-dependant variables. School whiting (Sillago flindersi) fish length and otolith weight measurements were used in a numerical example. Different combinations and sample sizes of input data were used for numerical error analysis.
Geographic variation and juvenile migration in Atlantic redfish inferred from otolith microchemistry
Authors: Stransky Christoph , Garbe-Schönberg C.-Dieter , Günther Detlef
Published: July 2005

Golden redfish (Sebastes marinus) and deep-sea redfish (S. mentella) are heavily exploited fish resources in the North Atlantic, but their stock delineation remains unresolved. The present study examined the use of otolith microchemistry as a stock separation tool for redfish. By determining minor and trace elements in redfish otoliths from various areas in the North Atlantic, geographic and temporal variations in otolith microchemistry were investigated. Relatively high temporal stability in otolith elemental composition was found for juvenile redfish from nursery areas off East Greenland. Elemental concentrations in the nucleus, juvenile and marginal otolith zones differed significantly between areas and showed consistent longitudinal trends for some elements. Multivariate analysis of element constituents by area, however, revealed poor geographic separation (< 50% cross-validated classification) for both species. Otoliths of juvenile S. mentella from demersal nursery grounds and adjacent pelagic habitats showed no significant differences between areas. The results are in accordance with the recently observed low morphometric and genetic heterogeneity of redfish across the North Atlantic. It is, however, unclear if the lack of clear spatial separation by natal signatures is due to a common origin of the investigated fish or due to limited variability of the chemical composition of their ambient environment.
Relationship between elemental concentration and age from otoliths of adult snapper (Pagrus auratus, Sparidae): implications for movement and stock structure
Authors: Fowler A. J. , Gillanders B. M. , Hall K. C.
Published: July 2005

The present study investigated the stock structure of snapper (Pagrus auratus) in South Australia, and the extent to which this is influenced by adult movement. Fish from the 9+ age class were sampled from six different regions, encompassing >2000 km of coastline and different habitat types. The chemistry of transverse sections of otoliths was sampled using laser ablation inductively coupled plasma-mass spectrometry, providing elemental profiles that were related to age for the first nine years of the fish’s lives. The age-related annual averages for both 88Sr and 138Ba differed significantly between regions. They were, however, similar for the first three years, then diverged considerably between the ages of three to five years, and then remained consistently different through to the age of nine years. This suggests that all fish, regardless of where captured, originated from only one or two nursery areas, but dispersed throughout the different regions between the ages of three to five years, before becoming resident to their new regions of occupancy. Thus, this population of snapper represents a single, large, stock where the individuals have a common origin, but through age-related emigration ultimately disperse and supplement the low abundance populations in regional State waters.
Statoliths as 'black boxes' (life recorders) in squid
Authors: Arkhipkin Alexander I.
Published: July 2005

The present study presents an overview of recent developments in statoliths studies. Statoliths are calcareous structures located in the equilibrium organs of cephalopods, which serve to detect body accelerations during movement in water. They are perfect ‘black boxes’ because they record a lot of information about the lives of squid and cuttlefish. For instance, it is possible to reveal the hatchling size and temperature of embryonic development, estimate age and growth rates of the animal with daily precision, date life transitions, analyse possible migratory routes and population structure of squid using trace element analysis, and even reveal how many spawning events a given animal has had by analysing statolith microstructure. Furthermore, because the paralarval statolith is embedded completely within the adult statolith, its features can be used to identify cephalopod paralarvae, which are sometimes very different from adult animals. The shape of statoliths is physiologically specific, which enables the determination of the movement pattern of the animal. Statoliths are usually one of the few remains of squid in fossil records, and their features can be used to infer ideas about the life styles of extinct species.
Otolith shape contour analysis using affine transformation invariant wavelet transforms and curvature scale space representation
Authors: Parisi-Baradad V. , Lombarte A. , Garcia-Ladona E. , Cabestany J. , Piera J. , Chic O.
Published: July 2005

Fish otolith morphology has been closely related to landmark selection in order to establish the most discriminating points that can help to differentiate or find common characteristics in sets of otolith images. Fourier analysis has traditionally been used to represent otolith images, since it can reconstruct a version of the contour that is close to the original by choosing a reduced set of harmonic terms. However, it is difficult to locate the contour’s singularities from this spectrum. As an alternative, wavelet transform and curvature scale space representation allow us to quantify the irregularities of the contour and determine its precise position. These properties make these techniques suitable for pattern recognition purposes, ageing, stock determination and species identification studies. In the present study both techniques are applied and used in an otolith classification system that shows robustness against affine image transformations, shears and the presence of noise. The results are interpreted and discussed in relation to traditional morphology studies.
Otolith shape feature extraction oriented to automatic classification with open distributed data
Authors: Piera J. , Parisi-Baradad V. , García-Ladona E. , Lombarte A. , Recasens L. , Cabestany J.
Published: July 2005

The present study reviewed some of the critical pre-processing steps required for otolith shape characterisation for automatic classification with heterogeneous distributed data. A common procedure for optimising automatic classification is to apply data pre-processing in order to reduce the dimension of vector inputs. One of the key aspects of these pre-processing methods is the type of codification method used for describing the otolith contour. Two types of codification methods (Cartesian and Polar) were evaluated, and the limitations (loss of information) and the benefits (invariance to affine transformations) associated with each method were pointed out. The comparative study was developed using four types of shape descriptors (morphological, statistical, spectral and multiscale), and focused on data codification techniques and their effects on extracting shape features for automatic classification. A new method derived from the Karhunen–Loève transformation was proposed as the main procedure for standardising the codification of the otolith contours.
Elemental composition of otoliths as a discriminator of life stage and growth habitat of the European eel, Anguilla anguilla
Authors: Tzeng W. N. , Severin K. P. , Wang C. H. , Wickström H.
Published: July 2005

The hypothesis that elemental composition of otoliths of the eel (Anguilla spp.) changes with life stage and growth habitat was tested in the present study. The minor elements Cl, Na, K, Mg, Ca, Sr and P in otoliths of European eels (Anguilla anguilla) were examined by using an Electron Probe Microanalyser (EPMA) equipped with wavelength dispersive spectrometers (Cameca SX-50). Yellow-stage eels were collected from coastal waters and lakes of Sweden in 1987, 1988, 1991, and 1994, with ages ranging from 5 to 18 years old. Strontium maps and profiles of Sr : Ca ratio, as well as the elver check in otoliths, were used to classify life history stages of the eels as leptocephalus, and freshwater- and seawater-resident yellow eels. Canonical score plots of the otolith elemental compositions of the freshwater-resident yellow eel were completely separated from those of leptocephalus and seawater-resident yellow eel, but the latter two partially overlapped. Strontium is the primary component in determining the discrimination, but the nutrient-related (S and P), and the physiologically controlled elements (Na and Cl), may also play an important role in the discrimination. These results indicate that multiple-elemental information can provide additional insight into the migratory environmental history of diadromous fishes.
Mixing of populations or year class twinning in Norwegian spring spawning herring?
Authors: Husebø Å. , Slotte A. , Clausen L. A. W. , Mosegaard H.
Published: July 2005

In the present study, we question whether the mixing of autumn spawning herring with Norwegian spring spawning herring (Clupea harengus L.) in feeding and wintering areas is a result of year class twinning, that is, that they hatched in spring as products of the spring spawning stock, but ended up spawning in autumn. The otolith microstructure of the summer feeding autumn spawners (July 2001) was similar to the wintering autumn spawners (January 2002), stable and low in comparison with the sympatric spring spawners caught in the same two seasons. Hence, the otolith microstructure of the analysed larval herring seemed representative of their own spawning season. Data from 1982 to 2003 demonstrated that the fraction of autumn spawners by year class has been quite low at 1–14%, but relatively high in some of the weak year classes, indicating a different recruitment success between the spawning groups. Length at age and somatic weight at length did not differ between the spawning groups. In comparison, the neighbour North Sea autumn spawning herring were significantly smaller at the same age.
Accuracy and precision in stock separation of north-east Arctic and Norwegian coastal cod by otoliths - comparing readings, image analyses and a genetic method
Authors: Berg Erik , Sarvas Tuula H. , Harbitz Alf , Fevolden Svein Erik , Salberg Arnt Børre
Published: July 2005

The distinction between north-east Arctic cod and Norwegian coastal cod, two major groups of Atlantic cod (Gadus morhua L.), has for many years been based on different distance and shape similarities between the two first translucent growth zones in the otoliths, subjectively decided by visual inspection in a binocular. To analyse the certainty of this technique, four independent readers have classified 263 cod otoliths in total from five different geographical areas. For three of the readers, between 82% and 89% of the classification results coincided with independent results based on genetic analyses. Further, 38 cod otoliths, where the readers were certain of the classification (21 north-east Arctic cod and 17 coastal cod) were classified by several image analysis methods. A complete separation was obtained by using the ratio of the circumferences of the two zones, providing a typical ratio of approximately 2 for coastal and 1.5 for north-east Arctic cod. The otolith method for separating the two types of cod has been considered adequately accurate in assessing the two stocks of cod. However, the method is sensitive to subjective interpretation, and action needs to be taken to minimise the difference in interpretation among otolith readers.
Can otolith chemistry be used for identifying essential seagrass habitats for juvenile spotted seatrout, Cynoscion nebulosus, in Chesapeake Bay?
Authors: Dorval Emmanis , Jones Cynthia M. , Hannigan Robyn , van Montfrans Jacques
Published: July 2005

We investigated the variability of otolith chemistry in juvenile spotted seatrout from Chesapeake Bay seagrass habitats in 1998 and 2001, to assess whether otolith elemental and isotopic composition could be used to identify the most essential seagrass habitats for those juvenile fish. Otolith chemistry (Ca, Mn, Sr, Ba, and La; δ13C, δ18O) of juvenile fish collected in the five major seagrass habitats (Potomac, Rappahannock, York, Island, and Pocomoke Sound) showed significant variability within and between years. Although the ability of trace elements to allocate individual fish may vary between years, in combination with stable isotopes, they achieve high classification accuracy averaging 80–82% in the Pocomoke Sound and the Island, and 95–100% in the York and the Potomac habitats. The trace elements (Mn, Ba, and La) provided the best discrimination in 2001, a year of lower freshwater discharge than 1998. This is the first application of a rare earth element measured in otoliths (La) to discriminate habitats, and identify seagrass habitats for juvenile spotted seatrout at spatial scales of 15 km. Such fine spatial scale discrimination of habitats has not been previously achieved in estuaries and will distinguish fish born in individual seagrass beds in the Bay.
Tracing the life history of individual barramundi using laser ablation MC-ICP-MS Sr-isotopic and Sr/Ba ratios in otoliths
Authors: McCulloch Malcolm , Cappo Mike , Aumend James , Müller Wolfgang
Published: July 2005

Otoliths preserve a continuous geochemical record of its life history, from the earliest natal stage through to adulthood. Using in situ laser ablation (UV) multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) measurements of Sr isotopic compositions together with elemental abundances (Ca, Sr, Ba and Mg), we show how it is possible to characterise the various types of habitats encountered throughout the lifecycle history of individual barramundi. Unlike trace element concentrations, which can be modulated by physiological processes, Sr isotopic compositions of otoliths provide a direct fingerprint of the water mass in which the fish lived. Elemental abundances, in particular Sr/Ba ratios are, however, shown to be especially sensitive to transitional environments, such as estuaries. The flexibility of the barramundi’s life history is confirmed by the present study, with the existence of both marine and freshwater nurseries, with some individuals spending their entire life cycle in fresh water, some entirely in marine and others moving between freshwater estuarine and marine habitats.
Development of a robust classifier of freshwater residence in barramundi (Lates calcarifer) life histories using elemental ratios in scales and boosted regression trees
Authors: Cappo Mike , De'ath Glenn , Boyle Steve , Aumend James , Olbrich Roland , Hoedt Frank , Perna Colton , Brunskill Gregg
Published: July 2005

Field and experimental studies showed that solution-based analysis of scales could be used to discriminate the long-term freshwater residents in the coastal fishery for catadromous barramundi. A new, robust classification technique was developed using boosted regression trees (MART) and its performance was compared with traditional linear discriminant analysis (LDA). The non-parametric MART had errors 33–81% less than LDA, and could account for non-linear relationships and interactions among elemental ratios. The best model used Sr : Ca, Ba : Ca, Fe : Ca and Mn : Ca in scales as predictors of salinity regime. Analysis of scales collected repeatedly from sub-adult fish of known environmental history showed the MART classifier could identify fish of freshwater origin until at least 10 months residence in seawater, and possibly several years, but scale growth rate could affect the temporal stability of the classifier after that time. The experiment indicated an approximate fourfold rise in Sr : Ba ratios in new scale margins, which were strongly classified by the MART as coming from saltwater fish, but inner scale sections of the same scales were still correctly classified as coming from freshwater fish. We conclude that solution-based elemental analyses of whole scales, and also annuli within scales, could offer a cost-effective, non-destructive technique to help understand the mechanisms causing enhanced year-class strength following high freshwater outflows.
Recent growth rate of larval pilchards Sardinops sagax in relation to their stable isotope composition, in an upwelling zone of the East Australian Current
Authors: Uehara Shinji , Syahailatua Augy , Suthers Iain M.
Published: July 2005

The recent growth rate and stable isotope composition of larval pilchards, (Sardinops sagax, 6–29 mm standard length), captured in surface and near-surface waters, were examined in coastal upwelling and non-upwelling regions of the East Australian Current over two cruises during the austral summer of 1998/1999. Compared to the non-upwelled regions, larvae were larger in the upwelling regions, and yet the back-calculated recent growth over 2 days before capture was significantly less on both cruises. This surprising result is consistent with slower larval growth of this species near coastal Japan and California, where strong year classes may form in offshore waters. δ15N ratios were significantly correlated with larval length, indicating ontogeny in their diet. In November, slower growers in upwelled waters were enriched in δ15N and depleted in δ13C, consistent with expected ratios from diets derived from deeper water. The pilchard’s early life history off eastern Australia is proposed and compared with that off eastern Japan.
Bomb radiocarbon and lead - radium disequilibria in otoliths of bocaccio rockfish (Sebastes paucispinis): a determination of age and longevity for a difficult-to-age fish
Authors: Andrews Allen H. , Burton Erica J. , Kerr Lisa A. , Cailliet Gregor M. , Coale Kenneth H. , Lundstrom Craig C. , Brown Thomas A.
Published: July 2005

Longevity estimates for the bocaccio rockfish (Sebastes paucispinis) using traditional techniques range from less than 20 years to approximately 50 years. Otoliths of bocaccio are difficult to age, and previous attempts to validate ages have been unsuccessful. Because otolith age suggests the bocaccio are reasonably long-lived, lead–radium dating was used in an attempt to independently age bocaccio otoliths. The measured 210Pb and 226Ra activities were among the lowest reported and resulted in poor radiometric age resolution; however, the break-and-burn technique clearly underestimated age in some cases with the longevity of the bocaccio being at least 31 years. To provide better age resolution, the bomb radiocarbon approach was applied to individual otoliths. Based on measured radiocarbon levels relative to a reference time-series, several specimens were aged at approximately 30–40 years. To evaluate these determinations, the remaining otolith of the pair was sectioned and aged blind. The result was an excellent fit to the reference time-series and a validation of the age estimates. The maximum age from growth zone counts was 37 ± 2 years, which is consistent with a reported maximum age of approximately 50 years.
Why otoliths? Insights from inner ear physiology and fisheries biology
Authors: Popper Arthur N. , Ramcharitar John , Campana Steven E.
Published: July 2005

Otoliths are of interest to investigators from several disciplines including systematics, auditory neuroscience, and fisheries. However, there is often very little sharing of information or ideas about otoliths across disciplines despite similarities in the questions raised by different groups of investigators. A major purpose of this paper is to present otolith-related questions common to all disciplines and then demonstrate that the issues are not only similar but also that more frequent interactions would be mutually beneficial. Because otoliths evolved as part of the inner ear to serve the senses of balance and hearing, we first discuss the basic structure of the ear. We then raise several questions that deal with the structure and patterns of otolith morphology and how changes in otoliths with fish age affect hearing and balance. More specifically, we ask about the significance of otolith size and how this might affect ear function; the growth of otoliths and how hearing and balance may or may not change with growth; the significance of different otolith shapes with respect to ear function; the functional significance of otoliths that do not contact the complete sensory epithelium; and why teleost fishes have otoliths and not the otoconia found in virtually all other extant vertebrates.
Otolith research and application: current directions in innovation and implementation
Authors: Begg Gavin A. , Campana Steven E. , Fowler Anthony J. , Suthers Iain M.
Published: July 2005

The Third International Symposium on Fish Otolith Research and Application was held in Townsville, Queensland, Australia from 11 to 16 July 2004. The overall theme was ‘Innovation and Implementation’, a collection of which is published here (Volume 56, Issue 5). Although age and growth studies predominated at the Symposium, new areas of quality-control assurance, annual-increment formation in deep-sea and tropical fish, image analysis and two-dimensional feature extraction were demonstrated. New statistical approaches were also evident, particularly in the subsampling of commercial data for estimating age compositions. The chemical composition of otoliths as natural data loggers has greatly advanced since the 1998 Symposium, with the advent of micromilling machines, new instrumentation and the use of isotopes rather than elements as environmental indicators. Otoliths will continue to support modern environmental needs for fisheries, marine park assessment, metapopulation conservation and the management of stocks and biodiversity of fish.
Practice and problems with gastrostomies
Authors: McHattie Gill
Published: July 2005

The development of gastrostomy placement has been an important technological advance in the enteral-access field. However, its rapid growth in popularity could be viewed as problematic. The endoscopist or intervention radiologist can no longer act as a technician but requires to follow-up this group of patients in order to determine outcomes that will inform future practice. There has been emphasis on the importance of the multidisciplinary team in informing and assessing patients referred for gastrostomy insertion. Communication between all the professionals caring for a patient and between the carers and the patient allows information to be collated that will determine the benefits and burdens of long-term gastrostomy feeding. At present much of the published experience is limited to the acute care setting. The incidence of complications varies, depending on the investigator's definition of complication and the diagnosis of the patient group. Many reported studies are retrospective, which puts limitations on documentation. Increasing numbers of patients with diverse needs are now being discharged into the community with gastrostomy tubes in place. Whilst the hospital should ensure that written protocols are provided and that all carers involved should have adequate training, it is not unusual for patients to receive mixed messages from the different care teams responsible for their care. In South Glasgow NHS Hospital Division key members of all teams caring for these patients (acute care, community district nurses, learning disabilities team, physical disabilities team and commercial homecare companies) meet regularly to discuss equipment and protocols. The members of this group feel that this approach has improved communication, standardised practice and reduced complications by providing a service that delivers artificial nutrition support but is primarily suited to the patient's disease process.
Authors: Buttriss Judith , Nugent Anne
Published: July 2005

The prevalence of obesity, overweight and type 2 diabetes are increasing in all regions of Europe. Obesity is already commonplace, affecting 10–20% of men and 10–25% of women, and by 2010 approximately 31 million of the population will require treatment for diabetes and its related complications, including the ‘metabolic syndrome’ (a cluster of cardiovascular risk factors). Associated health and social welfare costs are expected to rise to economically unsustainable levels in Europe as a direct result of these trends. Effective strategies are needed to tackle this major public health problem and to decrease dependence on medical management. These issues are the focus of LIPGENE (FOOD-CT-2003-505944), funded by the European Commission, which will investigate the interactions between dietary constituents and the genome in the development of chronic diseases, such as the metabolic syndrome, and will utilise new technologies to identify novel solutions. The LIPGENE consortium comprises twenty-five research centres across Europe. Features of the 5-year work programme include a major human nutrition intervention study in eight European cities, development of a sustainable vegetable oil product naturally rich in long-chain n-3 fatty acids, and identification of a protocol for feeding dairy cows that will result in milk with a more favourable fatty acid composition. Other work packages will provide a detailed economic analysis of the current and future healthcare costs associated with the metabolic syndrome, and an analysis of consumer attitudes. There is also a dissemination programme associated with the project that features conferences, workshops and associated publications.
Metabolic syndrome: what is it and what are the implications?
Authors: Shaw D. I. , Hall W. L. , Williams C. M.
Published: July 2005

Obesity and overweight are linked with a cluster of metabolic and vascular disorders that have been termed the metabolic syndrome. Although there is not yet a universally-accepted set of diagnostic criteria, most expert groups agree that the syndrome is characterised by impaired insulin sensitivity and hyperglycaemia, dyslipidaemia (elevated blood triacyglycerols with depressed HDL-cholesterol), abdominal obesity and hypertension. Based on existing published criteria estimates suggest that the syndrome affects a substantial percentage of the middle-aged and elderly populations of most European countries (10–20%) and confers increased risk of type 2 diabetes (2–8.8-fold) and CVD (1.5–6-fold), as well as having a marked effect on morbidity. Although the pathophysiology is incompletely understood, insulin resistance and abdominal obesity are central to subsequent abnormalities in circulating glucose and lipoproteins, and vascular function that lead to type 2 diabetes, atherosclerosis and CVD. The link between metabolic syndrome, type 2 diabetes and CVD, as well as inability to reverse the present rising rates of obesity, will lead to economically-unsustainable costs of health care in the next 10–20 years. Preventative strategies for metabolic syndrome are required to slow rates of progression and to reduce dependence on costly medical management. A notable development is recent evidence that shows that diet and exercise are more effective than drug treatment in preventing the development of type-2 diabetes in high-risk individuals. The LIPGENE project will investigate dietary fat quality as a strategy for the prevention of metabolic syndrome and identify food chain approaches that can support consumer attempts to alter their dietary patterns.
The prevalence and costs of obesity in the EU
Authors: Fry James , Finley Willa
Published: July 2005

The present paper reports on results obtained as part of the economics module of the LIPGENE project. It reviews recent trends in obesity in the fifteen member states of the EU (the member states before enlargement in 2004) and concludes that in 2002 for both adult men and women at least half the fifteen member states of the EU had obesity levels of >20%. In the same year the total direct and indirect annual costs of obesity in the fifteen member states of the EU were euro32 800×106. The provision of ‘healthy’ foods with an adapted lipid profile provides one means of mitigating the impact of obesity. However, there are extra costs associated with the supply of such foods, via additional costs of food ingredients, identity preservation costs for premium-value food products and the penalties caused by the inability to exploit economies of scale. The limited scale of the markets for healthy foods is caused by their high selling prices. Also presented is an analysis of the costs of subsidising, throughout the EU, ingredients that improve the fatty acid profile of beef, eggs, poultry meat and low-fat spreads, so that healthier versions of these products sell at the same price as traditional alternatives. The total costs of such subsidies for these four food products would have been euro10×109/year in 2002, which was 30% of the direct and indirect costs of obesity.
The production of very-long-chain PUFA biosynthesis in transgenic plants: towards a sustainable source of fish oils
Authors: Napier Johnathan A. , Sayanova Olga
Published: July 2005

There is now considerable evidence of the importance of n-3 long-chain PUFA in human health and development. At the same time, the marine fish stocks that serve as the primary sources of these fatty acids are threatened by continued over-exploitation. Thus, there is an urgent need to provide a sustainable alternative source of the n-3 long-chain PUFA normally found in fish oils. The possibility of using transgenic plants genetically engineered to synthesise these important fatty acids has recently been demonstrated. The approaches taken to realise this outcome will be discussed, as will their prospects for providing a sustainable resource for the future.
The parent's perspective
Authors: Culverwell Teresa
Published: July 2005

The present paper gives an insight from a parent's perspective into the roles of health professionals and service providers in the daily management of a child with complex needs that include enteral feeding. It focuses on the case of a 9-year-old boy and discusses some aspects of his diagnosis and treatment, and the support received. It highlights the need for a multi-agency approach based around the child, in which parents are consulted, the opinions of professionals from the different disciplines are valued by other professionals and professionals do not issue conflicting advice but share knowledge before giving advice. There should be national accessibility to support services and a standardised training programme for carers. Better communication between parents, carers, health professionals and service providers and working together can reduce the stress for the patient and carer, and put less strain on much-needed resources.
Repetition priming of access to biographical information from faces
Authors: Johnston Robert A. , Barry Christopher
Published: July 2005

Two experiments examined repetition priming on tasks that require access to semantic (or biographical) information from faces. In the second stage of each experiment, participants made either a nationality or an occupation decision to faces of celebrities, and, in the first stage, they made either the same or a different decision to faces (in Experiment 1) or the same or a different decision to printed names (in Experiment 2). All combinations of priming and test tasks produced clear repetition effects, which occurred irrespective of whether the decisions made were positive or negative. Same-domain (face-to-face) repetition priming was larger than cross-domain (name-to-face) priming, and priming was larger when the two tasks were the same. It is discussed how these findings are more readily accommodated by the Burton, Bruce, and Johnston (1990) model of face recognition than by episode-based accounts of repetition priming.
The influence of phoneme position overlap on the phonemic similarity effect in nonword recall
Authors: Nimmo Lisa M. , Roodenrys Steven
Published: July 2005

The current research examined the predictions that short-term memory models generate for the phonological similarity effect, when similarity was defined in different ways. Three serial recall experiments with consonant–vowel–consonant (CVC) nonwords are reported, where the position of the phonemes that list items shared was manipulated (i.e., shared vowel and final consonant [_VC; Experiment 1], initial consonant and vowel [CV_; Experiment 2], or the two consonants [C_C; Experiment 3]. The results show that the position of common phonemes in nonwords has differential effects on order and item information. The findings are discussed in relation to previous research into the effect of phonemic similarity on nonword recall, and modifications to current short-term memory models are proposed.
Linguistic and nonlinguistic influences on the eyes' landing positions during reading
Authors: White Sarah J. , Liversedge Simon P.
Published: July 2005

Two eye tracking experiments show that, for near launch sites, the eyes land nearer to the beginning of words with orthographically irregular than with regular initial letter sequences. In addition, the characteristics of words, at least at the level of orthography, influence the direction and length of within-word saccades. Importantly, these effects hold both for lower case and for visually less distinctive upper case text. Furthermore, contrary to previous evidence (Tinker & Paterson, 1939), there is little effect of type case on reading times. Additional analyses of oculomotor behaviour suggest that there is an inverted optimal viewing position for single fixation durations on words. Both the supplementary analyses and the effects of orthography on fixation positions are relevant to current models of eye movements in reading.
Dual-goal facilitation in Wason's 2–4–6 task: What mediates successful rule discovery?
Authors: Gale Maggie , Ball Linden J.
Published: July 2005

The standard 2–4–6 task requires discovery of a single rule and produces success rates of about 20%, whereas the dual-goal (DG) version requests discovery of two complementary rules and elevates success to over 60%. The experiment examined two explanations of DG superiority: Evans’ (1989) positivity-bias account, and Wharton, Cheng, and Wickens’ (1993) goal-complementarity theory. Two DG conditions were employed that varied the linguistic labelling of rules (either positively labelled Dax vs. Med, or mixed-valence “fits” vs. “does not fit”). Solution-success results supported the goal-complementarity theory since facilitation arose in both DG conditions relative to single-goal tasks, irrespective of the linguistic labelling of hypotheses. DG instructions also altered quantitative and qualitative aspects of hypothesis-testing behaviour, and analyses revealed the novel result that the production of at least a single descending triple mediates between DG instructions and task success. We propose that the identification of an appropriate contrast class that delimits the scope of complementary rules may be facilitated through the generation of a descending instance. Overall, our findings can best be accommodated by Oaksford and Chater's (1994) iterative counterfactual model of hypotheses testing, which can readily subsume key elements of the goal-complementarity theory.
Gender differences in memory for object and word locations
Authors: Cattaneo Zaira , Postma Albert , Vecchi Tomaso
Published: July 2005

It has been hypothesized that gender differences in visuo-spatial working memory (VSWM) are larger in tasks requiring active elaboration of the material. In the present study we explored this issue by using an object relocation task, with both verbal and visual stimuli. The involvement of active processes was manipulated through the type of transformation required on the stimulus and through the introduction of different kinds of interference. In the three experiments reported, participants were shown either words or cartoon object icons in different locations and had to relocate them in either the same format or in the opposite one (object icons could be transformed into words and vice versa). Males outperformed females in the most demanding conditions, in which object icons and words were presented together in the encoding phase, and both had to be transformed in the recall phase; or when more demanding interferences were used. Our data suggest that the retention strategy was similar for the two groups and that the gender effect is related to a selective female difficulty associated with the increase in active VSWM processing. These findings further support the hypothesized distinction between the passive and active components of VSWM and illustrate the role that this distinction might play in accounting for individual differences.
Evidence of immediate activation of gender information from a social role name
Authors: Reynolds David , Garnham Alan , Oakhill Jane
Published: July 2005

Two experiments investigated whether the stereotypical gender of a character is encoded immediately into the discourse representation and influences later comprehension. In Experiment 1 people read, and were confused by, a short story in which an incongruity arises at the end if the gender of a character introduced by a social role name has been inferred. In Experiment 2 online measures confirmed that readers were slower to read the final clause of the passage. In addition, a follow-up verification question revealed that these readers did not immediately resolve the inconsistency by inferring the appropriate gender for the role term. These findings provide strong evidence for gender activation at the time that a role name is encoded. The implications of these results for the mental representation of gender information and for constraints on inference during text comprehension are discussed.
How rats perform spatial working memory tasks: Limitations in the use of egocentric and idiothetic working memory
Authors: Futter J. E. , Aggleton J. P.
Published: July 2005

Rats of the Dark Agouti strain were trained on delayed alternation under conditions that should encourage egocentric working memory. In two experiments a T-maze was set within a cross-maze so that different arms could be used for the sample and test runs. The maze had high opaque side-walls, and testing was conducted in low light levels so that distal visual cues might be eliminated. By rotating the maze 90° between the sample and choice run and by using two identical mazes set side by side it was possible to nullify other spatial strategies. Experiments 1 and 2 showed that rats preferentially used place information, intramaze cues, and direction cues, even though only egocentric or idiothetic (nonmatch-to-turn) working memory could successfully solve every trial. Rats were able to maintain an accurate sense of location within the maze even though distal cues were not visible and the animal was moved between the sample and choice runs. Experiment 2 confirmed that another rat strain (Long-Evans) shows the same learning profiles. Both experiments indicate that rats are very poor at using either egocentric or idiothetic information to alternate, and that retention delays as short as 10 s can eliminate the use of these forms of memory.
K Channel Subconductance Levels Result from Heteromeric Pore Conformations
Authors: Chapman Mark L. , VanDongen Antonius M.J.
Published: July 2005

Voltage-gated K channels assemble from four identical subunits symmetrically arranged around a central permeation pathway. Each subunit harbors a voltage-sensing domain. The sigmoidal nature of the activation kinetics suggests that multiple sensors need to undergo a conformational change before the channel can open. Following activation, individual K channels alternate stochastically between two main permeation states, open and closed. This binary character of single channel behavior suggests the presence of a structure in the permeation pathway that can exist in only two conformations. However, single channel analysis of drk1 (Kv2.1) K channels demonstrated the existence of four additional, intermediate conductance levels. These short-lived subconductance levels are visited when the channel gate moves between the closed and fully open state. We have proposed that these sublevels arise from transient heteromeric pore conformations, in which some, but not all, subunits are in the “open” state. A minimal model based on this hypothesis relates specific subconductance states with the number of activated subunits (Chapman et al., 1997). To stringently test this hypothesis, we constructed a tandem dimer that links two K channel subunits with different activation thresholds. Activation of this dimer by strong depolarizations resulted in the characteristic binary open–close behavior. However, depolarizations to membrane potentials in between the activation thresholds of the two parents elicited highly unusual single channel gating, displaying frequent visits to two subconductance levels. The voltage dependence and kinetics of the small and large sublevels associate them with the activation of one and two subunits, respectively. The data therefore support the hypothesis that subconductance levels result from heteromeric pore conformations. In this model, both sensor movement and channel opening have a subunit basis and these processes are allosterically coupled.
Skeletal Muscle HIF-1α Expression Is Dependent on Muscle Fiber Type
Authors: Pisani Didier F. , Dechesne Claude A.
Published: July 2005

Oxygen homeostasis is an essential regulation system for cell energy production and survival. The oxygen-sensitive subunit α of the hypoxia inducible factor-1 (HIF-1) complex is a key protein of this system. In this work, we analyzed mouse and rat HIF-1α protein and mRNA expression in parallel to energetic metabolism variations within skeletal muscle. Two physiological situations were studied using HIF-1α–specific Western blotting and semiquantitative RT-PCR. First, we compared HIF-1α expression between the predominantly oxidative soleus muscle and three predominantly glycolytic muscles. Second, HIF-1α expression was assessed in an energy metabolism switch model that was based on muscle disuse. These two in vivo situations were compared with the in vitro HIF-1α induction by CoCl2 treatment on C2C12 mouse muscle cells. HIF-1α mRNA and protein levels were found to be constitutively higher in the more glycolytic muscles compared with the more oxidative muscles. Our results gave rise to the hypothesis that the oxygen homeostasis regulation system depends on the fiber type.