bluuebunny/crossref_metadata_2025 huggingface dataset:
Towards a framework for benchmarking ICT practice, competence and performance in small firms
Authors: Wainwright David , Green Gill , Mitchell Ed , Yarrow David
Published: April 2005

Purpose

This paper aims to provide a review and critique of the benchmarking literature with respect to information and communication technology (ICT) adoption and usage within small firms. This is used as the basis for developing a competence based model contingency framework to be used for comparing practice and performance with respect to ICT within small firms.

Design/methodology/approach

A theoretical approach is proposed whereby the key metrics and questions related to the development of an ICT benchmarking framework are derived from recent empirical research reported in the literature.

Findings

The main findings indicate a paucity of empirical research with respect to benchmarking ICT and also underdeveloped theory in terms of IT adoption in small firms. The ICT competence and capability approach is proposed as a viable research avenue for investigating IT performance within small firms.

Research limitations/implications

Limitations of this research are related to its current phase as work in progress. Testing of the theoretical framework and its development within the context of comparing ICT performance across small firms has yet to be carried out.

Practical implications

Practical implications of the research are very high as there could be a direct link between adoption and use of the benchmarking tool and improved ICT performance.

Originality/value

The development of an ICT benchmarking framework and tool that is directly focused on improving small firm performance – linked to a human and organisational competence approach as opposed to only measuring technological capability.
A novel and accurate guide to customer satisfaction
Authors: Thornton S.A.
Published: April 2005

Purpose

Aims to provide a quantifiable metric for a library management activity.

Design/methodology/approach

A light‐hearted view of a serious and commonly undertaken library management activity. For the last nine years the author has been trying to identify effective and easily quantifiable metrics for customer satisfaction for special libraries.

Findings

This has proved far more difficult than the author had hoped, as customers always seemed perfectly satisfied, and even when they were not, they usually blamed themselves. Following the creation of the Defence Science and Technology Laboratory (Dstl) after the partial privatisation of the UK's Defence Evaluation and Research Agency, the drive for more accurate satisfaction measurement became more urgent, and became a personal performance target on the author's annual review.

Originality/value

A light hearted view of a topic of concern for all library professionals.
Using Engel curves to estimate bias in the Canadian CPI as a cost of living index
Authors: Beatty Timothy K.M. , Larsen Erling Røed
Published: April 2005

Abstract.  Semiparametric Engel curves are used to infer bias in the Canadian CPI as a Cost of Living Index. The budget share of food has long been used as an indicator of welfare. We compare households with the same levels of CPI deflated total expenditure over the period 1978–2000. Differences in the expenditure share of food are attributed to the CPI failing to capture changes in costs of living. We employ a novel econometric approach using a single index penalized linear spline model. Over the period, we find that the CPI overstated changes in the cost of living between 1.33 and 1.86% for the four household types considered. JEL classification: D1, C1
Chondrodermatitis nodularis helicis as a marker of internal syndromes associated with microvascular injury
Authors: Magro Cynthia M. , Frambach Gwyn E. , Crowson A. Neil
Published: April 2005

Abstract:  Chondrodermatitis nodularis helicis (CNH) is held to be an idiopathic degenerative process involving the upper dermis of the auricular rim. Chondrodermatitis typically occurs in elderly men where associations with underlying trauma and sun exposure have been postulated as potential inciting triggers. Its association as a marker of systemic disease is not well established. We describe 24 patients with CNH, in whom there were also significant underlying diseases largely associated with vascular injury including those of immune‐based etiology and/or conditions which have been previously linked with granuloma annulare, another necrobiotic process of collagen. These patients with concomitant systemic disease were characteristically younger compared to the classic demographics described for CNH. In some cases, chondrodermatitis may represent an ischemic necrobiotic disorder of collagen, potentially defining an important sign of underlying systemic disease in younger patients.
Nucleolar organizer region staining patterns in paraffin‐embedded tissue cells from human skin cancers
Authors: Romão‐Corrêa Rosana F. , Maria Durvanei A. , Soma Mithitaka , Sotto Mírian N. , Sanches José Antônio , Neto Cyro Festa , Ruiz Itamar R. G.
Published: April 2005

Background:  Increased number of nucleoli (nucleolar organizer regions, NORs) with abnormal shapes and sizes, including small dots, has been used as prognostic tools to evaluate tumor proliferation levels and troublesome borderline lesions. In this study, NOR patterns of skin cancers were performed in the search of a valuable prognostic method to complement other histological procedures.

Methods:  Paraffin‐embedded tumor tissue was obtained from basal and squamous cell carcinomas, cutaneous malignant melanoma, premalignant lesions, and Skmel‐28 human melanoma cells. Slices were dewaxed and AgNOR stained. The patterns were scored and submitted for statistical analyses.

Results:  All types of cancer cells showed variable numbers of abnormally shaped nucleoli and dot‐like structures. Only tumor cells presented four or more nucleoli, with or without dots, while 85% of the normal cells had one single NOR without dots. Most data were statistically significant when compared to normal cells. As a whole, squamous cell carcinoma and malignant melanoma tumor cells had less NOR alterations than basal cell carcinoma (BCC) tumor types.

Conclusions:  Changes in the number and shape of nucleoli present in malignant cells could be attributed to increased levels on rDNA transcription on cancer cells, besides abnormal remodeling of chromatin, which could disrupt proper nucleoli association. Increased genetic alterations on malignant basal cells could contribute to impair invasive and migration abilities of BCC tumors.
Erythroderma with lichenoid granulomatous features induced by erythropoietin
Authors: Wolf Ingrid H. , Smolle J. , Cerroni L. , Kerl H.
Published: April 2005

The increasing use of new drugs in cancer therapy, especially growth factors, hormones, and chemotherapies resulted in several reports of unusual skin eruptions. We studied a patient with erythroderma who had received erythropoietin because of myeloma with tumor anemia. The histological features were characterized by a lichenoid, focally granulomatous infiltrate with predominance of histiocytes. It is important for dermatopathologists to recognize this interesting pattern induced by erythropoietin.
Comparison of benign keratoses using p53, bcl‐1, and bcl‐2
Authors: Ko Christine J. , Shintaku Peter , Binder Scott W.
Published: April 2005

While cell‐cycle markers have been used to differentiate benign vs. malignant lesions and to classify malignant lesions, benign keratoses have not been well studied using such markers. We hypothesized that inflammation or irritation of benign keratoses may be related to a shift in the cell cycle. We compared the immunohistochemical staining patterns of 10 seborrheic keratoses (SKs), 10 inflamed seborrheic keratoses (iSKs), and 10 inverted follicular keratoses (IFKs) using antibodies to p53, bcl‐1, and bcl‐2. Staining with antibodies to p53 was slightly increased in IFKs compared with iSKs or non‐inflamed seborrheic keratoses. Bcl‐1 staining was similar in all lesions. A population of bcl‐2‐positive dendritic cells was seen within the epidermal portion of IFKs. Keratinocyte bcl‐2 staining was significantly higher in SKs compared with the other two keratoses. Bcl‐2 may be increased in SKs as an anti‐apoptotic mechanism.
Myxoinflammatory fibroblastic sarcoma of the neck
Authors: McFarlane Rob , Meyers Arlen D. , Golitz Loren
Published: April 2005

Background:  Myxoinflammatory fibroblastic sarcoma (MIFS), also named inflammatory myxohyaline tumor of distal extremities with virocyte or Reed‐Sternberg cells, is a rare tumor typically presenting as a painless mass in the extremities.

Patients:  We present an unusual case of MIFS presenting as a subcutaneous neck mass. This is the first reported case of MIFS presenting in the neck.

Results:  Therefore, this lesion must be considered in the differential diagnosis for painless subcutaneous masses presenting not only in the distal extremities, but also in the neck.

Conclusion:  MIFS has only recently been recognized. The differential diagnosis for MIFS is broad, and it can often be mistaken for several different inflammatory and neoplastic processes, which may require different treatment.
Fatal subcutaneous panniculitis‐like T‐cell lymphoma with interface change and dermal mucin, a dead ringer for lupus erythematosus
Authors: Ma Linglei , Bandarchi Bizhan , Glusac Earl J.
Published: April 2005

We report a 48‐year‐old man who presented with ulcerated plaques and nodules of the lower extremities. Skin biopsies revealed a dense lymphocytic infiltrate involving the dermis and the subcutis in a lobular and septal pattern. No overt cytological atypia was present. Notably, several features resembling lupus erythematosus were present, including vacuolar interface change and abundant dermal mucin deposition. The patient developed pulmonary nodules, and a lung biopsy showed a perivascular and interstitial lymphoid infiltrate without overt atypia. The cutaneous and pulmonary lymphoid infiltrates showed similar immunohistochemical profiles: CD3+ CD4– CD8+/– CD56+. Monoclonal rearrangements of the T‐cell receptor γ gene with similar migration patterns were identified from both locations. The patient developed fatal hemophagocytic syndrome, involving liver, spleen, lymph nodes, and bone marrow. This case is one amongst the rare reports of subcutaneous panniculitis‐like T‐cell lymphoma with systemic involvement.
Two cases of angiomyxolipoma (vascular myxolipoma) of subcutaneous tissue
Authors: Lee Hae‐Woong , Lee Dong‐Kyung , Lee Mi‐Woo , Choi Jee‐Ho , Moon Kee‐Chan , Koh Jai‐Kyoung
Published: April 2005

Abstract:  Angiomyxolipoma (vascular myxolipoma) is a recently described rare variant of lipoma, four cases of which have been reported to date. Microscopically, the lesion consists of adipose tissue without lipoblasts, extensive myxoid areas, and numerous blood vessels. The main differential diagnosis of this lesion is myxoid liposarcoma, and other adipocytic lesions such as myxolipoma, myxoid spindle cell lipoma should be included. We report two cases of angiomyxolipoma located in the subcutaneous tissue of the forearm and the wrist.
Interorganizational Collaboration and Innovation: Toward a Portfolio Approach*
Authors: Faems Dries , Van Looy Bart , Debackere Koenraad
Published: April 2005

In the literature on innovation, interorganizational collaboration has been advanced as beneficial for the innovative performance of firms. At the same time, large‐scale empirical evidence for such a relationship is scarce. This article examines whether evidence can be found for the idea that interorganizational collaboration supports the effectiveness of innovation strategies. This article empirically addresses this research question by analyzing data on Belgian manufacturing firms (n=221) collected in the Community Innovation Survey, a biannual survey organized by Eurostat and the European Commission aimed at obtaining insights into the innovation practices and performance of companies within the various European Union (EU) member states. Tobit analyses reveal a positive relationship between interorganizational collaboration and innovative performance. At the same time, the impact on innovative performance differs depending on the nature of the partner(s) involved. These findings strongly suggest the relevance of adopting a portfolio approach to interorganizational collaboration within the context of innovation strategies.
Book Reviews
Authors: Smith Preston G.
Published: April 2005

Books reviewed in this issue:

▪Achieving Project Management Success Using Virtual Teams

▪Virtual and Collaborative Teams: Process, Technologies, and Practice

▪International Product Liability Law, a Worldwide Desk Reference

▪Mass Affluence: Seven New Rules of Marketing to Today's Consumer

▪Creating the Project Office: A Manager's Guide to Leading Organizational Change

▪The Complete Project Management Office Handbook
Fish stock assessment in lakes based on mass removal
Authors: Helminen H. , Ennola K. , Hirvonen A. , Sarvala J.
Published: April 2005

The efficiency of mass removal of fishes can potentially be assessed using catch statistics collected during intensive fishing periods. The calculations are based on the general assumption that a decline in population size will produce a decline in catch per unit effort (cpue). When the removal is efficient it is possible to estimate the population size both at the beginning of the fishing period and after the removal.

Two examples are based on the winter seine net fishing of vendace (Coregonus albula) in Lake Pyhäjärvi, SW Finland in (1) 1983–1984 and (2) 1989–1990. The effects of the error in catch composition samples and random changes in probabilities of capture during the removal period on the final estimates of initial stock sizes are also examined.

The precision of the population estimates shown here was greatly influenced by the violation of the underlying assumption that the probability of capture is equal for all members of the target age group. In any case, particular attention should be paid to optimizing the sampling programme so that it will reveal the best information on the exploited stock with the resources in hand.
Effects of solar radiation on the population dynamics of juvenile flatfish in the shallows of the Wadden Sea
Authors: Berghahn R. , Bullock A. M. , Karakiri M.
Published: April 2005

During the first days after their arrival in the Wadden Sea, newly settled plaice Pteuronectes platessa L., flounder, Platichthys flesus L., and sole, Solea solea L., stay at low tide in the residual waters on the tidal flats. Here they can be exposed to high levels of solar radiation and extreme temperature conditions. As a result of the extreme temperatures, all settlers eventually leave the shallows and start to exhibit tidally‐phased feeding migrations from the tidal channels on to the submerged fiats, In contrast to warm summers, for example 1982, no formation of a hyaline zone could be detected in the otoliths of surviving O‐group plaice in 1990, 4 weeks after such a mass emigration, which could be directly observed on particular days in both hot and cold summers. Analysis of UV‐B radiation data indicated that in 1990 cloud cover and wind conditions during the settling period protected the post‐larvae from high temperature and radiation stress which is necessary to induce hyaline zones in the otoliths. Nevertheless, histological examination of the dorsal skin revealed cellular changes characteristic of sunburn damage in part of‐the O‐group plaice population in 1990.

Mortality of O‐group plaice during and after such a mass emigration, which was directly observed in the drainage gulleys in 1982, was estimated at approximately 14–27%. This rate is assumed to be close to the maximum mortality which can be expected from abiotic factors for O‐group plaice in the Wadden Sea.
The effects of seasonal acclimatization on correlates of growth rate in juvenile cod, Gadus morhua
Authors: Foster A. R. , Hall S. J. , Houlihan D. F.
Published: April 2005

The effects of seasonal acclimatization (i.e. simulated autumn and winter water temperature and photoperiod) on the specific growth rate, liver‐somatic index, white muscle protein and RNA concentration of juvenile cod were investigated. Winter acclimatization resulted in cod having higher liver‐somatic indices and white muscle RNA concentrations. The influence of environmental conditions on growth rate indices of cod are discussed in the light of these results.
Nutrient‐dependent variation in growth and longevity of the red bandfish, Cepola macrophthalma, in the Aegean Sea
Authors: Stergiou K. I.
Published: April 2005

Statistically significant regressions are presented between the maximum observed age, maximum gross weight, mean total length, mean gross weight, and mean weighted back‐calculated total length at ages 3 and 4 years for red bandfish, Cepola macrophthalma, and the total nitrogen in three Aegean gulfs. In contrast, the regressions of all the above mentioned biological variables on phosphates in the three gulfs were not significant, a fact consistent with the view that nitrogen, as opposed to phosphorus, is the limiting factor in eastern Mediterranean marine ecosystems. After discussing possible genetic discontinuities between the three populations, being inferred from the paleoceanography of the study area, it is suggested that the three populations form a single gene pool expressing phenotypic plasticity shaped by the contrasting environmental conditions experienced.
Fecundity of whitefish (Coregonus lavaretus) during the eu‐and oligotrophication of Lake Constance
Authors: Hartmann J. , Quoss H.
Published: April 2005

About 20 ovaries of the whitefish ‘Blaufelchen’ (Coregonus lavaretus L.) of Lake Constance (Bodensee) were collected annually from 1964‐1991. Absolute and relative fecundity peaked in the early 1980s, lagging about 2 years behind the maximum of total‐P in the water (during the circulation period). Out of the biological time‐series of Lake Constance, whitefish fecundity is the only one known to follow the phosphorus curve, and this may be the first time‐series documented case of parallel trend reversal in the trophic state of a lake and fish biology. It is concluded that fish fecundity serves, at best, as an unspecific monitor of the overall well‐being of the fish.
Euryhaline adaptations in the fat sleeper, Dormitator maculatus
Authors: Nordlie F. G. , Haney D. C.
Published: April 2005

Salinity tolerances and plasma osmotic concentrations were determined in the fat sleeper, Dormitator maculatus, a common species in estuarine and coastal fresh waters along the Atlantic and Caribbean coasts of North, Central and South America. Analyses followed sequential laboratory acclimations to a series of ambient salinities at a constant temperature of 20 ± 1° C and photoperiod of 12L: 12D. These fish tolerated a range of ambient salinities from fresh water through a salinity of 75‰. Plasma osmotic concentrations were regulated at an essentially constant level in the salinity range from fresh water through a salinity of 50‰, beyond which plasma concentrations trended upward with increased ambient salinity. We conclude that D. maculatus, while truly euryhaline, docs not show the extreme euryhalme capabilities of several teleost fishes that are ‘full‐time’ estuarine inhabitants.
Cortisol and immune characteristics in rainbow trout (Oncorhynchus mykiss) selected for high or low tolerance to stress
Authors: Fevolden S. E. , Røed K. H.
Published: April 2005

The influence of exposure to stressors on cortisol and the non‐specific immune traits lysozyme and serum haemolytic activity were examined in second generation rainbow trout (Oncorhynchus mykiss) selected for either high or low serum cortisol level following a confinement stress. Lysozyme and serum haemolytic activity were also assessed, together with levels of specific antibodies against Aeromonas salmonicida A‐layer, Vibrio salmonicida O‐antigen and Vibrio anguillarum O‐antigen, following injection of vaccines against these pathogens.

Significant differences in mean cortisol levels between the two selection lines were observed, but in only one of two stress experiments was the ‘high‐stress’ line found to have the higher cortisol level; in the other experiment the ‘high‐stress’ line had significantly lower cortisol levels than the ‘low‐stress’ line. Lysozyme levels were in four of four assessments higher in the high‐stress line than in the low‐stress line, whereas components of serum haemolytic activity tended to be lower in the high‐stress line than in the low‐stress line. Levels of specific antibodies against all three bacterial pathogens were elevated following the injection of the vaccines. Only antibody production against A. salmonicida A‐layer was significantly different between the two lines, the higher production of antibody being in the high‐stress line.
The analysis of metabolites in rainbow trout white muscle: a comparison of different sampling and processing methods
Authors: Wang Yuxiang , Wilkie Michael P. , Heigenhauser George J. F. , Wood Chris M.
Published: April 2005

We have investigated the effects of different sampling and processing methods on metabolite concentrations [glycogen (Gly), glucose (Glu), lactate (Lac), pyruvate (Pyr), ammonia (Amm), creatine phosphate (PCr), creatine (Cr), and adenosine triphosphate (ATP)] measured in white muscle of rainbow trout at rest and immediately after exhaustive exercise. When samples were taken from resting fish by rapid needle biopsy (without anaesthesia), direct freezing of the needles in liquid N2 yielded lower Lac and Glu levels than if the muscle cores were quickly blown out into liquid N2. However, killing of the fish by an overdose of MS‐222 followed by freeze‐clamping of excised muscle was superior to the biopsy method in preserving high levels of PCr and Gly (91 and 62% higher, respectively). In parallel, the MS‐222 method also yielded lower levels of Amm (80%) and Lac (47%). Samples freeze‐clamped by the MS‐222 method were used to evaluate three methods of subsequent processing for enzymatic analysis of metabolites: classic glass homogenization (GH) in 8% perchloric acid (PCA) c. mortar and pestle (MP) pulverization or freeze‐drying (FD) prior to PCA extraction. For all metabolites, GH and MP methods produced similar values. However, the FD technique yielded 20% higher PCr levels which represented over 80% phosphorylation of the total Cr pool at rest, the highest ever reported via enzymatic analysis. Glu was also higher by FD, bul Gly, Lac, and ATP were not affected. Indeed ATP was relatively stable throughout all sampling and processing procedures. MP, GH, MP&GH combination, and high speed motor driven grinding techniques all yielded similar Amm levels in resting muscle. However, tests demonstrated that even brief thawing of tissue greatly elevated Amm, while FD resulted in artificially low Amm values due to evaporative losses during lyophilization. Overall, muscle sampling by freeze‐clamping on trout killed by MS‐222 overdose, followed by FD prior to PCA extraction, appears to be the best combination for the measurement of all white muscle metabolites except Amm, for which MP or GH are preferable.
Occurrence of Atlantic salmon parr in redds at spawning time
Authors: Erkinaro J. , Shchurov I. L. , Saari T. , Niemelä E.
Published: April 2005

Several Atlantic salmon parr of different sizes were found alive in salmon redds under a 10–30 cm layer of stones at spawning time. Parr, both mature and immature, remain inactive in redds during daylight but show nocturnal activity.
The influence of environmental manipulations on inter– and intra–individual variation in food acquisition and growth performance of Arctic charr, Salvelinus alpinus
Authors: Jobling M. , Baardvik B. M.
Published: April 2005

Repeated measurements of food intake made on juvenile Arctic charr, Salvelinus alpinus, held under different rearing conditions enabled examination of the effects of environmental manipulations on both intra– and inter–individual variations in food intake to be made. This permitted the assessment of the influences of differential food acquisition on individual growth rates and biomass gain. When charr were held in isolation individual fish showed relatively little day–to–day variability in food intake and inter–individual differences in intake were small (‘base–fine’ values). All fish exhibited positive rates of growth and the overall range was narrow. Nevertheless, there was a highly significant positive correlation between food intake and growth, indicating that those individuals that consumed the greatest quantities of food were also those that had the highest rates of weight gain. The rearing of charr in groups led to increases in both intra– and inter–individual variations in food intake to levels considerably above ‘base–line’. This increased variability in food intake was reflected in rates of weight gain being more variable amongst the charr reared in groups, with fish that lost weight often being recorded. Manipulation of the rearing environment had marked influences upon intra–individual variability in food intake, inter–individual differences in food acquisition and rates of weight gain. High stocking densities and exposure of the fish to moderate water currents were most effective in reducing levels of variability to approach those observed under ‘base–line’ conditions.
Differential response to water current in offspring of inlet‐and outlet‐spawning brown trout Salmo trutta
Authors: Jonsson N. , Jonsson B. , Skurdal J. , Hansen L. P.
Published: April 2005

Two‐year‐old hatchery‐reared progeny of inlet‐ and outlet spawning brown trout from Lake Tytifjorden were released at the mouth of the R. Imsa, south‐western Norway. There were significant differences in migratory direction of juveniles between the two populations. After release, juvenile fish from the outlet river population moved against the current and ascended the R Imsa, while the inlet rivet fish tended to migrate with the water current to the sea. This differential response to water current in juveniles appears to be due to genetic differences between the populations, and parallels that found in their ancestors native environments.
Size‐related differences in behaviour and spatial distribution of juvenile Atlantic salmon in a novel environment
Authors: Mikheev V. N. , Metcalfe N. B. , Huntingford F. A. , Thorpe J. E.
Published: April 2005

Within a month of first feeding sibling juvenile salmon had developed not only large differences in size (up to fivefold in weight), but also significant differences in behaviour. Large fish remained in refuges (overhead cover) significantly longer after having been frightened. On leaving the shelters most small fish established individual territories on the bottom and. downstream of the shelters. The greater aggressiveness of small fish in a novel environment (from holding tank to experimental stream) was related to this apparent territoriality. The increased shelter residence time and delayed establishment of individual territories might be interpreted as greater caution in large fish, which are able to avoid risky situations due to their higher energy reserves. In contrast, smaller fish need to leave refuges more quickly and to establish individual territories in a novel environment.
Heterosis in resistance to Ichthyophthirius multifiliis infections in poeciliid fish
Authors: Clayton G. M. , Price D. J.
Published: April 2005

Resistance to experimental infections of Ichthyophthirius multifiliis was investigated in the poeciliid fish Xiphophorus maculatus, X. variatus and their two reciprocal hybrids. A third species, the goodeid Ameca splendens, was infected for comparative purposes. Infection data were analysed using a generalized linear interactive modelling package (GLIM). Infection levels were not significantly influenced by the sex of the fish, temperature, or speciestemperature interactions, but body area and time of infection did affect susceptibility. After accounting for variation due to these factors, it was shown that the two reciprocal hybrids of X. maculatus and X. variatus had significantly lower infection levels than either parental stock. Heterosis, H, was calculated from both raw data (16.2%) and from modelled values (31.3%) after removal of environmental factors. This confirms the existence of genetic factors determining resistance to /. multifiliis infection and has shown that gains in resistance can be made through hybridization.
The standard metabolic rate of dolphin fish
Authors: Benetti D. D. , Brill R. W. , Kraul S. A.
Published: April 2005

The standard metabolic rates (SMRs) of 11 (1.395–4.125 kg) dolphin fish (mahimahi or dorado, Coryphaena hippurus) were measured at 25°± 0.5°C. Fish were prevented from swimming with neuromuscular blocking agents and force ventilated. Heart rates were determined simultaneously. SMRs (358–726 mg O2 h –1) were several times those of other similarly sized active teleosts such as salmonids, but close to those of tunas. Heart rates (84–161 beats min –1) were also high, but alike those of tunas under similar circumstances. As in tunas, the high SMR of dolphin fish may result from high osmoregulatory costs engendered by their large gill surface areas and/or other adaptations necessary for achieving exceptionally high maximum metabolic rates.
Clonal Atlantic salmon × brown trout hybrids produced by gynogenesis
Authors: Galbreath P. F. , Adams K. J. , Wheeler P. A. , Thorgaard G. H.
Published: April 2005

Clonal full‐sib progeny groups of Atlantic salmon Salmo salar× brown trout Salmo trutta hybrids were produced by gynogenesis. Eggs obtained from two 3‐year‐old Atlantic salmon (female) × brown trout (male) F1 hybrids were activated with UV‐irradiated rainbow trout Oncorhynchus mykiss sperm. Fecundity, percentage egg activation and percentage survival to completion of yolk‐sac absorption were similar for the two females, and averaged 800 eggs kg−1, 90 and 65%, respectively. Flow cytometric and protein electrophoretic analyses confirmed the progeny to be diploid hybrids. Isogenicity within progeny groups and to the maternal parent was indicated by identical DNA fingerprint patterns detected with multilocus oligonucleotide probes–GATA(5) and ACTG(n). Isogenicity was also observed in the gynogenetic progeny of a third female spawned the following year. It appeared that a large portion of the oocytes in females of this hybrid underwent a premeiotic chromosome doubling, or possibly a complete suppression of meiosis. The result was ovulation of diploid eggs, each possessing a full set of both Atlantic salmon and brown trout chromosomes identical to those in the maternal somatic cells. Lines of clonal hybrids could therefore be perpetuated by gynogenesis and would have potential both as experimental animals and in commercial aquaculture.
Migrations of three‐spined stickleback, nine‐spined stickleback, and pond smelt in the Chignik catchment, Alaska
Authors: Harvey C. J. , Ruggerone G. T. , Rogers D. E.
Published: April 2005

Upstream spawning migrations of age‐2 three‐spined stickleback, nine‐spined stickleback, and pond smelt, and subsequent downstream migrations of young‐of‐the‐year and age‐1 individuals are documented in Black River of the Chignik catchment, Alaska.
Maturation and fecundity of a stock‐enhanced population of striped bass in the Savannah River Estuary, U.S.A
Authors: Will T. A. , Reinert T. R. , Jennings C. A.
Published: April 2005

The striped bass Morone saxatilis population in the Savannah River (south‐eastern U.S.A.) collapsed in the 1980s, and recent eorts to restore the population have resulted in increased catch‐per‐unit‐eort (CPUE) of striped bass in the Savannah River Estuary (SRE). The abundance of eggs and larvae, however, remain well below historic levels. The primary cause of the population decline was remedied, and environmental conditions seem suitable for striped bass spawning. Regression analysis of data derived from ultrasonic imaging of 31 striped bass resulted in a statistical model that predicted ovary volume well (r2=0.95). The enumeration of oocytes from ovarian tissue samples and the prediction of ovary volume allowed fecundity to be estimated without sacrificing the fish. Oocyte maturation in Savannah River striped bass seemed to progress normally, with oocytes developing to final stages of maturity in larger fish (>750 mm LT). Additionally, fecundity estimates were comparable to a neighbouring striped bass population. The environmental cues needed to trigger development and release of striped bass oocytes into the SRE appeared to be present. If most of the striped bass females in the SRE are still young (<7 years), the ability to produce large numbers of eggs will be limited. As these young fish mature, egg production probably will increase and the density of striped bass eggs eventually will approach historic levels, provided suitable habitat and water quality are maintained.
The spermatozoon of the African catfish: fine structure, motility, viability and its behaviour in seminal vesicle secretion
Authors: Mansour N. , Lahnsteiner F. , Patzner R. A.
Published: April 2005

The spermatozoon of the African catfish Clarias gariepinus is a simple organized aquasperm although it reveals very unique characteristics: the cytoplasmic channel is lacking, the mitochondria form a complex structure and the arrangement of the centriolar complex is species specific. Semen has high initial motility rates (c. 70–90%) and swimming velocities (c. 120–140 μm s−1), the main swimming type is linear. Motility duration in water is 30 s and is prolonged only to 40 s in NaCl solutions or more complex bu ered motility activating saline solutions. A pH between 7.0 and 9.0 has no e ect on the sperm motility parameters. Motility is completely and reversibly suppressed in electrolyte and non‐electrolyte solutions with an osmolality of 200 mosmol kg−1. During immotile storage the sperm viability is influenced by the osmolality and the potassium levels of the storage medium, by the temperature and by the dilution. At optimal conditions (bu ered sperm motility inhibiting saline solution: 150 mmol l−1 NaCl, 2.5 mmol l−1 KCl, 1 mmol l−1 CaCl2, 1 mmol l−1 MgSO4, 20 mmol l−1 Tris solution, pH 8.5; dilution rate 1: 5; storage temperature, 4°C) sperm viability persists for >7 days. High viscosity of the pure seminal vesicle secretion completely inhibits the sperm motility. When the seminal vesicle secretion is diluted in water the viscosity decreases and the motility suppressing e ect is neutralized. When semen is mixed with seminal vesicle secretion the sperm viability decreases to zero within 10 min.
Short lifespan and apoptosis in Aphia minuta
Authors: Caputo V. , Candi G. , Arneri E. , La Mesa M. , Cinti C. , Provinciali M. , Nisi Cerioni P. , Gregorini A.
Published: April 2005

Evidence is presented that apoptosis of intestinal enterocytes is implicated in adult mortality immediately after the breeding season in Aphia minuta, a paedomorphic goby that spends its whole life cycle of <1 year in the water column as a pelagic and planktophagous fish. This could be the first documented case in which apoptosis triggers a population dynamic process such as natural mortality in a vertebrate.
Impact of rifting and hydrography on the genetic structure of Clarias gariepinus in eastern Africa
Authors: Giddelo C.S. , Arndt A.D. , Volckaert F.A.M.
Published: April 2005

In a study of the genetic structure of Clarias gariepinus at the ND5 and ND6 loci of mitochondrial DNA using RFLP–PCR in 16 populations (267 fish), a total of 18 haplotypes was detected. The most common haplotype was EA1 and represented 46% of all genotypes. Three phylogenetic groups characterized the region, with the East African clade occurring between the western rift in the west, Lake Baringo in the north, the Indian Ocean in the east and the Rufiji River in the south. The Lower Tana River (unlike the Upper Tana River) and Lake Kamnarok grouped with the North clade, while the Ruaha River (tributary of the Rufiji River) represented a contact zone between the East and the South‐central African clade. Genetic structure was distinct (FST=0·66), with the Lower Tana River and Lake Mtera forming specific units. Within the East clade, the Oloibortoto River, Upper Tana River and Lake Victoria each formed a distinct population. Lake Baringo grouped either with the eastern rift or the western rift depending on the analysis. Lake Jipe, the Pangani River, Rusizi River, Lake Edward, Nyabugogo River and the Luiche River clustered together. Among group variance explained 66·8% of the total variance; the impact of vicariance (rifting and uplifting) on the phylogeography was considerable. A distribution model of the catfish is proposed which combines the separation by rifting several million years ago with a high gene flow in the western rift due to historical connectivity among lakes and rivers.
‘Fish in hot water”: the challenges facing fish and fisheries research in tropical estuaries
Authors: Blaber S. J. M.
Published: April 2005

Tropical estuarine areas comprise small systems of a few km, larger estuaries, coastal lakes of hundreds of km 2 and vast shallow coastal waters that are contiguous with estuaries and have similar reduced salinities. Many of the world's great estuaries are in the tropics, e.g. the Amazon, Orinoco, Congo, Zambezi, Niger, Ganges and Mekong. The distribution of tropical and subtropical estuaries approximately follows that of mangroves. Like estuaries everywhere, they are a focus of human activity and are among the most exploited of ecosystems. In few other places do the activities of fishers, industrialists, shippers, farmers, conservationists, sports enthusiasts and biologists overlap to such an extent. Quite apart from the possible eects of all these activities, the fishes of subtropical and tropical estuaries already face one of the most rigorous of aquatic environments; but despite this, species diversity and productivity are high. Only in tropical estuaries are animals from such a wide range of taxa so closely associated, annelid worms, prawns, crocodiles, birds, ‘ hippos ’, dolphins and of course fishes, all may form part of the overall community, often with functional ecological links. Unfortunately, the diculties of working in these often inhospitable environments, has meant that biologists have favoured projects in more appealing areas, such as coral reefs. While it is still true that most estuarine research is conducted in industrialized developed countries, nearly all of which are in cold or temperate regions, there has been a recent upsurge in tropical estuarine fish research. This is being driven by two imperatives, food security and the conservation and maintenance of biodiversity. Both these problems require knowledge of the ecology of tropical estuarine fishes, particularly their relationships with the environment and the extent to which they are dependent on estuaries or adjacent habitats for survival.
Community structure and temporal variability of ichthyoplankton in North Brazilian mangrove creeks
Authors: Barletta‐Bergan A. , Barletta M. , Saint‐Paul U.
Published: April 2005

The species composition and dynamics of fish larvae in three mangrove creeks located in the Caeté Estuary (north Brazil) were studied monthly using a trap net during diurnal ebb tides. A total of 109 954 larvae, representing 25 families and 54 species, were collected from October 1996 to October 1997. The community was dominated numerically by a few species, a feature common for other estuarine fish populations. The most abundant taxa were estuarine species, namely the eleotrid Guavina guavina (46·7%) and the engraulid Anchovia clupeoides (14·9%). The sciaenid Cynoscion acoupa was the only marine species that used the mangroves extensively as a nursery site, occurring mainly at the postflexion stage. The size distribution of G. guavina did not produce shifting modes, indicating continuous transport out of the mangroves by tidal currents. Significantly lower species richness was observed in the late rainy season, primarily due to the emigration of marine species. Intermediate seasons were characterized by more complex larval fish assemblages. The temporal trends of the dominant species was influenced to a great degree by their life history strategy.
Experimental measurement of thermal preferenda in sea trout smolts
Authors: Clough S. C. , Turnpenny A. W. H. , Holden S. D. J.
Published: April 2005

Experiments were conducted to estimate the threshold water temperature rise (Δt) for avoidance by smolts of sea trout Salmo trutta. In three out of four experiments, the median avoidance threshold was found to be c. +6° C (+5·4 to +6·4° C). In the fourth experiment, the fish were able to detect and avoid temperature rises of < +1° C.
Fish and fisheries of the tidal Thames: management of the modern resource, research aims and future pressures
Authors: Colclough S. R. , Gray G. , Bark A. , Knights B.
Published: April 2005

In recent decades, following the cleanup in the 1960s, the Thames Estuary has become a major nursery ground for economic and conservation species, and has seen the development of substantial commercial and recreational fisheries. The Environment Agency has both sea fisheries and freshwater fisheries statutory powers in the estuary. A unique and focussed survey programme has been developed to inform management policies. A Fisheries Management Action Plan has been developed to promote integrated salmonid, eel Anguilla anguilla and sea fisheries management, promote nurseries, sustainable exploitation and habitat protection and enhancement. Data are used to influence water quality, water resources and flood defence management regimes and in the planning field to influence development proposals. Consensus and collaboration have been built through the Thames Estuary Partnership. Research aims identified through the Thames Estuary Research Forum are described together with future pressures on key species. The survey rationales being developed will contribute to new standard sampling strategies and classification scheme to meet the requirements of the E.U. Water Framework Directive.
Trends in abundance of benthic and demersal fish populations of the lower Forth Estuary, East Scotland, from 1982–2001
Authors: Greenwood M. F. D. , Hill A. S. , McLusky D. S.
Published: April 2005

The benthic and demersal fishes of the lower Forth Estuary, east Scotland, were sampled by Agassiz trawling from January 1982–December 2001. Three stations of varying distance from the mouth of the estuary were trawled at high and low water in 5 months of each year, a total of 30 trawls per annum using the same ship and net design throughout. Of 30 species collected over this period, whiting Merlangius merlangus was the most abundant, followed by eelpout Zoarces viviparus, pogge Agonus cataphractus, flounder Platichthys flesus and plaice Pleuronectes platessa. The 10 most abundant species accounted for 97·8% of the total benthic‐demersal fish abundance. There was no trend in total annual species richness sampled, though total annual abundance of fishes captured decreased significantly from 1982–2001. This was largely caused by significant declines in abundance of whiting and eelpout. Fatherlasher Myoxocephalus scorpius showed a significant linear increase. None of the seven remaining most abundant species exhibited significant trends in abundance. Decline of eelpout may be attributable to increases in water temperature adversely affecting reproductive success. This is suggested by a significant negative correlation of mean annual abundance with January bottom temperature in the previous year.
Comparison of fish impingement by a thermal power station with fish populations in the Ems Estuary
Authors: Hadderingh R. H. , Jager Z.
Published: April 2005

On an annual basis >10 million individuals of c. 35 fish species are impinged at the EC20 unit of the Eems power station located on the Ems Estuary. The most abundant are: herring Clupea harengus, gobies (Gobiidae), Nilsson's pipefish Sygnathus rostellatus, three‐spined stickleback Gasterosteus aculeatus and sprat Sprattus sprattus. The impingement shows a seasonal pattern which reflects the presence of the fishes in the estuary. The results are compared with other impingement studies at power stations on the Belgian and Dutch estuaries.

In 1995, the cooling water entrance was displaced from the shoreline to 300 m off the coast at the edge of the tidal channel. The effect of this relocation on the level of fish impingement, determined by comparing the ratio of fish density in the cooling water and in the estuary before (1992–1993) and after (1996–1997) the relocation of the intake canal is discussed.
Structure and diversity of fish assemblages on rocky and soft bottom shores on the Swedish west coast
Authors: Pihl L. , Wennhage H.
Published: April 2005

Density and biomass of fishes, from shallow rocky and soft bottom habitats on the Swedish west coast, showed large seasonal variation with low values in winter and spring and with peaks in June. Season was also the most important factor determining the fish assemblage structure. Within season, however, there was a clear separation in assemblage structure between rocky‐and soft‐bottom habitats. There were significantly higher total fish abundances and biomasses during night compared with day catches. On soft bottoms density and biomass of fishes decreased with increasing depth, but no such pattern was seen in rocky habitats indicating that the distribution of fishes was related to vegetation cover. Altogether, 53 fish species were recorded of which 30 were common to both habitats. Species richness was similar on rocky and soft bottoms. Of the 10 most abundant species found in rocky habitats four belonged to the Labridae and three to the Gadidae. The fish assemblage on soft bottoms were of a more mixed nature with representatives among the 10 dominants from six families (Clupeidae, Cottidae, Gadidae, Gobiidae, Labridae and Pleuronectidae). When ranking the 10 dominant fish species on rocky bottoms according to biomass c. 50% of the mass was Labridae, 19% Gadidae and 13% Cottidae. In soft bottom habitats, fish biomass was mainly distributed between six families. Pleuronectidae and Gadidae were dominant and each made up 25% of the biomass, whereas Labridae only contributed 4% of the fish mass. It is concluded that the fish assemblage in rocky habitats is dominated by permanent non‐commercial species (63% of biomass), whereas soft bottoms mainly function as nurseries for juvenile fishes and as feeding grounds for seasonal migrants of commercial species (80% of biomass).