bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Preschool Repetition Test: An Evaluation of Performance in Typically Developing and Clinically Referred Children
Authors: Chiat Shula , Roy Penny 
Published: May 2007

Purpose
To determine the psychometric properties of the Preschool Repetition (PSRep) Test (Roy & Chiat, 2004), to establish the range of performance in typically developing children and variables affecting this performance, and to compare the performance of clinically referred children.

Method

The PSRep Test comprises 18 words and 18 phonologically matched nonwords systematically varied for length and prosodic structure. This test was administered to a typical sample of children aged 2;0–4;0 (
n
= 315) and a clinic sample of children aged 2;6–4;0 (
n
= 168), together with language assessments.

Results
Performance in the typical sample was independent of gender and socioeconomic status but was affected by age, item length, and prosodic structure and was moderately correlated with receptive vocabulary. Performance in the clinic sample was significantly poorer but revealed similar effects of length and prosody and similar relations to language measures overall, with some notable exceptions. Test–retest reliability and interrater reliability were high.

Conclusion
The PSRep Test is a viable and informative test. It differentiates within and between typical and clinic samples of children and reveals some unusual profiles within the clinic sample. These findings lay the foundations for a follow-up study of the clinic sample for investigation of the predictive value of the test.
Discourse Skills of Boys With Fragile X Syndrome in Comparison to Boys With Down Syndrome
Authors: Roberts Joanne , Martin Gary E. , Moskowitz Lauren , Harris Adrianne A. , Foreman Jamila , Nelson Lauren 
Published: May 2007

PurposeThis study compared the conversational discourse skills of boys who have fragile X syndrome with and without autism spectrum disorder (ASD) with those of boys with Down syndrome and boys who are typically developing.MethodParticipants were boys who have fragile X syndrome with (n= 26) and without (n= 28) ASD, boys with Down syndrome (n= 29), and boys who are typically developing (n= 22). Turns during an examiner–child interaction consisting of structured and semistructured activities were coded for the boys' ability to maintain a topic of conversation and the frequency of perseveration.ResultsThe results revealed that boys who had both fragile X and ASD produced significantly more noncontingent discourse than did boys who had only fragile X, boys with Down syndrome, or typically developing boys. This finding was observed regardless of whether the topic was maintained or changed and whether the turn type was a response or initiation. Regardless of autism status, boys with fragile X used more perseveration than did boys in the other groups.ConclusionThese findings suggest that some aspects of the conversational discourse difficulties attributed to fragile X syndrome may be a function of the high rate of comorbidity between fragile X and autism, whereas some difficulties may be characteristic of fragile X syndrome.
Effects of turbidity on the spontaneous and prey-searching activity of juvenile Atlantic cod (Gadus morhua)
Authors: Meager Justin J , Batty Robert S 
Published: May 2007

Increasing turbidity in coastal waters in the North Atlantic and adjacent seas has raised concerns about impacts on Atlantic cod (Gadus morhua) using these areas as nurseries. A previous experiment (Meageret al.2005Can. J. Fish. Aquat. Sci.62, 1978–1984) has shown that turbidity (up to 28 beam attenuation m−1) had little effect on the foraging rate of juvenile cod. Although this was attributed to cod using chemoreception in conjunction with vision to locate prey, foraging rates may also be maintained by increased activity. Higher activity, however, is energetically costly and may offset benefits from increased foraging return.We examined the effects of turbidity on prey searching and spontaneous activity of juvenile cod in the laboratory, by measuring activity with and without prey cues. Activity of juvenile cod was nonlinearly affected by turbidity and was lower at intermediate turbidity, regardless of the presence of prey odour. Activity increased over time when prey odour was present and decreased when absent, but the effects of prey odour were similar across all turbidity levels. Position in the tank was unaffected by turbidity or prey odour. Reduced activity at intermediate turbidities is likely to offset longer prey-search times. At high turbidity (greater than 17 m−1), both longer prey-search times and higher activity indicate that increased energetic costs are probable.
The CXCR4 chemokine receptor in acute and chronic leukaemia: a marrow homing receptor and potential therapeutic target
Authors: Burger Jan A. , Bürkle Andrea 
Published: May 2007

SummaryChemokine (C‐X‐C motif) receptor 4 (CXCR4) is essential for homing and maintenance of haematopoietic stem cells in distinct stromal cell niches within the marrow. Chemotactic responsiveness of haematopoietic stem cells is restricted to the ligand for CXCR4, stromal cell‐derived factor‐1 (SDF‐1/CXCL12), which is constitutively secreted by marrow stromal cells. Myeloid and lymphoid leukaemia cells also express CXCR4 that induces leukaemia cell chemotaxis and migration beneath marrow stromal cells. CXCR4 expression levels have a major prognostic impact in acute myeloid leukaemia. There is growing in vitro and in vivo evidence that CXCR4 expression by leukaemia cells allows for homing and their retention within the marrow. As such, leukaemia cells appear to utilise CXCR4 to access niches that are normally restricted to progenitor cells, and thereby reside in a microenvironment that favours their growth and survival. CXCR4‐ and integrin‐mediated contact between leukaemia cells and stromal cells protects leukaemia cells from spontaneous and chemotherapy‐induced cell death and therefore may represent a mechanism to explain minimal residual disease and subsequent relapses commonly seen in the treatment of these diseases. This review summarises our current knowledge regarding the importance of CXCR4 in acute and chronic leukaemia, discusses the importance of CXCR4 detection by flow cytometry in the diagnostic workup of leukaemia patients, and introduces the potential role of CXCR4‐targeting compounds for the treatment of leukaemia patients.
Building resilience and resistance against racism and discrimination among Salvadorian female youth in Canada
Authors: Carranza Mirna E. 
Published: May 2007

ABSTRACTThis paper reports on the findings of a qualitative study (32 in‐depth interviews) with Salvadorian mothers and their daughters. In particular this paper focuses on the strategies that mothers and daughters utilized to resist prejudice and racism in their settlement country, Canada. Findings contribute to the literature specifically by drawing attention to the importance of ethnic pride in helping mothers and their daughters bridge significant strains that arise in their acculturation process.
Dispersal dynamics of post‐larval blue crabs, Callinectes sapidus, within a wind‐driven estuary
Authors: REYNS NATHALIE B. , EGGLESTON DAVID B. , LUETTICH RICHARD A. 
Published: May 2007

ABSTRACTWe examined how post‐larval blue crab (Callinectes sapidus) dispersal occurs within Pamlico Sound, NC, USA, a predominantly wind‐driven system. We sampled during multiple 24‐h periods over 2 years (2000–01) to relate the spatial distribution of post‐larvae in the water column with circulation patterns. A hydrodynamic model of the region was used to recreate dispersal trajectories and to assess potential transport mechanisms and pathways that link near‐inlet and across‐Sound nursery habitats. Most post‐larval blue crabs were collected in surface waters at night, and were consistently distributed within the north‐western region of Pamlico Sound. Particle‐tracking simulations suggested that dispersal from the inlets to across‐Sound nursery habitats only resulted from the combination of tidal and wind‐driven currents. Our simulation results further indicated that the northernmost inlet (Oregon Inlet) was the primary supplier of post‐larval blue crabs throughout the northern basin of Pamlico Sound, as crabs ingressing through Hatteras Inlet to the south were not retained within our study area. A dispersal pathway connecting Oregon Inlet and across‐Sound settlement habitats was evident from field observations. Collectively, our results indicate how multiple forcing agents, coupled with post‐larval vertical positioning within the water column, drive estuarine dispersal and connect spatially separated nursery habitats.
An individual‐based model for the direct conversion of otolith into somatic growth rates
Authors: HINRICHSEN H.‐H. , BUEHLER V. , CLEMMESEN C. 
Published: May 2007

ABSTRACTOtolith increment width and larval fish data (length and weight) were used to develop an individual‐based model (IBM) to describe daily resolved growth rates of North Sea herring (Clupea harengus) larvae (Autumn Spawners) caught during International Herring Larvae Surveys in the ICES area IVa from 1990 to 1998. The model combines sagittal otolith readings (core and individual increment measurements), larval standard length and weight data, and solves an over‐determined set of linear system equations for all parameters using the method of least square residuals. The model consists of a matrix, which describes the increment width formation of 119 larvae, a vector containing their length/weight measurements, and a vector describing residuals. The solution vector yields age‐dependent maximum somatic growth rates of herring larvae up to an age of 41 days with sizes ranging from 10 to 25 mm. The observed environmental temperature in which larvae dwelled was relatively uniform. Therefore, measured increment width was individually used to determine daily growth from any single larva in relation to their potential maximum growth under optimal feeding conditions. The results are discussed with respect to the spatial and temporal variability of larval occurrence. Finally, an analysis of error estimation of the larval growth characteristics is presented.
Diets of top predators indicate pelagic juvenile rockfish (Sebastesspp.) abundance in the California Current System
Authors: MILLS K. L. , LAIDIG T. , RALSTON S. , SYDEMAN W. J. 
Published: May 2007

ABSTRACTDiets of top predators may be useful indicators to the availability of forage fish in marine ecosystems. Juvenile rockfish (young‐of‐the‐yearSebastesspp.) compose a significant part of the diet for many predators in the central California Current, including chinook salmon (Oncorhynchus tshawytscha), and several species of marine birds and mammals. Herein, we develop annual indices of juvenile rockfish relative abundance by collating time series data sets on: (i) the proportion of rockfish in the diet of three species of seabirds breeding on Southeast Farallon Island (1975–2002); (ii) the number of rockfish in chinook salmon stomachs (1980–99); and (iii) the abundance of rockfish captured in scientific mid‐water trawl net surveys (1983–2002). We used Principal Component Analysis (PCA) to combine indices, and refer to these as ‘Multivariate Rockfish Indices’ (MRI). Combining time series verifies the patterns shown by each alone and provides a synoptic perspective on juvenile rockfish relative abundance. The diets of predators with the largest foraging ranges (Common Murre,Uria aalge) and chinook salmon co‐varied strongly with the net samples, and appear to be the best indicators. The salmon also sampled species ofSebastesnot caught in the nets. The MRI reveals interannual variability in juvenile rockfish abundance, a substantial decline in abundance in the 1990s, and a partial recovery in the early 2000s. Predator‐based sampling is a cost‐effective enhancement of scientific net sampling.
Benthic organic carbon influences denitrification in streams with high nitrate concentration
Authors: ARANGO CLAY P. , TANK JENNIFER L. , SCHALLER JAMIE L. , ROYER TODD V. , BERNOT MELODY J. , DAVID MARK B. 
Published: May 2007

Summary1. Anthropogenic activities have increased reactive nitrogen availability, and now many streams carry large nitrate loads to coastal ecosystems. Denitrification is potentially an important nitrogen sink, but few studies have investigated the influence of benthic organic carbon on denitrification in nitrate‐rich streams.2. Using the acetylene‐block assay, we measured denitrification rates associated with benthic substrata having different proportions of organic matter in agricultural streams in two states in the mid‐west of the U.S.A., Illinois and Michigan.3. In Illinois, benthic organic matter varied little between seasons (5.9–7.0% of stream sediment), but nitrate concentrations were high in summer (>10 mg N L−1) and low (<0.5 mg N L−1) in autumn. Across all seasons and streams, the rate of denitrification ranged from 0.01 to 4.77 μg N g−1 DM h−1 and was positively related to stream‐water nitrate concentration. Within each stream, denitrification was positively related to benthic organic matter only when nitrate concentration exceeded published half‐saturation constants.4. In Michigan, streams had high nitrate concentrations and diverse benthic substrata which varied from 0.7 to 72.7% organic matter. Denitrification rate ranged from 0.12 to 11.06 μg N g−1 DM h−1 and was positively related to the proportion of organic matter in each substratum.5. Taken together, these results indicate that benthic organic carbon may play an important role in stream nitrogen cycling by stimulating denitrification when nitrate concentrations are high.
Trout affect the density, activity and feeding of a larval plethodontid salamander
Authors: BARR GARRETT E. , BABBITT KIMBERLY J. 
Published: May 2007

Summary1. Ecologists have struggled to describe general patterns in the impacts of predators on stream prey, particularly at large, realistic spatial and temporal scales. Among the confounding variables in many systems is the presence of multiple predators whose interactions can be complex and unpredictable.2. We studied the interactions between brook trout (Salvelinus fontinalis) and larval two‐lined salamanders (Eurycea bislineata), two dominant vertebrate predators in New England stream systems, by examining patterns of two‐lined salamander abundance in stream reaches above and below waterfalls that are barriers to fish dispersal, by measuring the effects of trout on salamander density and activity using a large‐scale manipulation of brook trout presence, and by conducting a small‐scale laboratory experiment to study how brook trout and larval two‐lined salamanders affect each other's prey consumption.3. We captured more salamanders above waterfalls, in the absence of trout, than below waterfalls where trout were present. Salamander density and daytime activity decreased following trout addition to streams, and salamander activity shifted from aperiodic to more nocturnal with fish. Analysis of stomach contents from our laboratory experiment revealed that salamanders eat fewer prey with trout, but trout eat more prey in the presence of salamanders.4. We suggest that as predators in streams, salamanders can influence invertebrate prey communities both directly and through density‐ and trait‐mediated interactions with other predators.
Predicting local biological characteristics in streams: a comparison of landscape classifications
Authors: PYNE MATTHEW I. , RADER RUSSELL B. , CHRISTENSEN WILLIAM F. 
Published: May 2007

Summary1. Landscape classifications group tracts of land based on similar physico‐chemical attributes that may affect the biological characteristics of streams at local scales. We tested the ability of five landscape models to account for variation in algal and macroinvertebrate biomass, brook trout (Salvelinus fontinalis) growth and macroinvertebrate community composition from 132 riffles in 15 catchments in the Big Horn Mountains, Wyoming.2. A model created by the U.S. Forest Service (FS) combined catchment and ecoregion approaches to classify the landscape. Our model used digital elevations to create a landscape classification for streams (DEM). The last three models were based on: (1) standard ecoregions (Ecoregion), (2) the type of underlying bedrock (Geology) and (3) the geographical distance between sites (Site Proximity model).3. Overall, the Ecoregion and Geology models performed better than the two catchment models (FS and DEM) in predicting local biological characteristics. The Geology model was best at predicting differences in algal and macroinvertebrate biomass, the Site Proximity and Ecoregion models were best at predicting patterns of similarity in macroinvertebrate community composition, and the Site Proximity, Ecoregion, Geology, and FS models, in order from best to worst, accounted for significant variation in brook trout growth. The Site Proximity model performed well because of the effects of spatial autocorrelation. The DEM was consistently one of the worst models at predicting local biological characteristics because it failed to include important attributes (e.g. dominant geology). Calcareous geology was positively associated with greater macroinvertebrate biomass and faster brook trout growth, but it was inversely related to algal biomass.4. None of the models accounted for a large amount of variation in local biological characteristics. Single‐scale, landscape classifications may never accurately predict variation in local biological characteristics because: (1) landscapes show a high degree of spatial heterogeneity, (2) local effects are stronger than landscape attributes and (3) there are too many intervening levels between landscape and local scales in the nested hierarchy of streams. However, landscape classifications did account for significant variation in biological characteristics. Thus, they would be a valuable management tool as part of a multi‐scale, hierarchical technique for classifying stream ecosystems.
Factors influencing the variability of pigments in the surface sediments of mountain lakes
Authors: BUCHACA TERESA , CATALAN JORDI 
Published: May 2007

Summary1. Surface sediment biofilm samples from 82 Pyrenean lakes were analysed for marker pigment composition using high performance liquid chromatography (HPLC).2. Variability in the pigment composition among lakes was investigated by multivariate statistical analyses using a large data set of factors describing lake chemical, physical, morphological and catchment characteristics.3. Due to the widely varying light penetration in the lakes, the most significant gradient of pigment composition extended from a benthic to a planktonic signal. The most important pigments in the gradient were alloxanthin (cryptophytes marker pigment, planktonic signal) and diatoxanthin (diatoms marker pigment, benthic signal). The molar ratio between these two marker pigments was positively correlated with lake depth.4. Chlorophyll‐a preservation was found to be positively related to light penetration and the development of an autothrophic biofilm on the surface sediment and negatively related to decreasing pH and the percentage of alpine meadows in the lake catchments.5. Zooplankton marker pigments in the surface sediment, including grazing by‐products (e.g. phaeophorbides) and carotenoids (astaxanthin, canthaxanthin, echinenone) incorporated into their tissues, were correlated with the areal abundance of zooplankton.6. Marker pigments for photosynthetic bacteria, BChl‐e and okenone, were found mainly in relatively shallow lakes with large catchments that are forested, probably because of their higher loading of allochthonous organic matter.7. The evaluation of a preservation index (Chl‐a expressed as a percentage of a‐phorbins) and the alloxanthin/diatoxanthin ratios throughout the sediment record of mountain lakes can provide evidence of historical changes in the relative importance of planktonic versus benthic primary production and might ultimately be interpreted in terms of climatic or environmental changes.
Users’ views of prison health services: a qualitative study
Authors: Condon Louise , Hek Gill , Harris Francesca , Powell Jane , Kemple Terry , Price Sally 
Published: May 2007

Abstract Title. Users’ views of prison health services: a qualitative study. Aim.  This paper is a report of a study of the views of prisoners about health services provided in prisons.Background.  Prison provides an opportunity for a ‘hard to reach’ group to access health services, primarily those provided by nurses. Prisoners typically have high health and social needs, but the views and experiences of prisoners about health services in prison have not been widely researched.Method.  Semi‐structured interviews were carried out with 111 prisoners in purposively selected 12 prisons in England in 2005. Interviews covered both prisoners’ views of health services and their own ways of caring for their health in prison. Interviews were analysed to develop a conceptual framework and identify dominant themes.Findings.  Prisoners considered health services part of a personal prison journey, which began at imprisonment and ended on release. For those who did not access health services outside prison, imprisonment improved access to both mental and physical health services. Prisoners identified accessing services, including those provided by nurses, confidentiality, being seen as a ‘legitimate’ patient and living with a chronic condition as problems within the prison healthcare system. At all points along the prison healthcare journey, the prison regime could conflict with optimal health care.Conclusion.  Lack of autonomy is a major obstacle to ensuring that prisoners’ health needs are fully met. Their views should be considered when planning, organizing and delivering prison health services. Further research is needed to examine how nurses can ensure a smooth journey through health care for prisoners.
The attitudes of Chinese family caregivers of older people with dementia towards life sustaining treatments
Authors: Kwok Timothy , Twinn Sheila , Yan Elsie 
Published: May 2007

Abstract Title. The attitudes of Chinese family caregivers of older people with dementia towards life sustaining treatments Aim.  This paper is a report of a study to examine attitudes towards life‐sustaining treatment in family caregivers of older Chinese people with dementia.Background.  Deferring decisions about life‐sustaining treatments to surrogate decision‐makers is common among older people with dementia. However, surrogate decision‐makers frequently lack knowledge about disadvantages and benefits of treatments and do not understand the principles of surrogate decision‐making.Method.  A total of 51 Chinese family caregivers were interviewed during 2003 and 2004. The interview included an assessment of their knowledge about cardiopulmonary resuscitation and tube feeding, a questionnaire to assess their anticipated decisions for four treatments (cardiopulmonary resuscitation, artificial ventilation, tube feeding and antibiotic administration) if the older relative suffered critical illness or irreversible coma, and their comfort and certainty in making such decisions.Findings.  Family caregivers displayed poor knowledge about life‐sustaining treatments, with 30 (59%) and 13 (26%) unable to name any feature of cardiopulmonary resuscitation and tube feeding, respectively. Most relied on their own views in decision‐making rather than on what they thought their relative would have wanted. Most family caregivers were reluctant to forgo treatments. Nursing home residence predicted family caregivers’ willingness to forgo artificial ventilation for critical illness. Financial burden predicted inclination to forgo antibiotics for critical illness and irreversible coma, as well as tube feeding in irreversible coma.Conclusion.  More dialogue and education are needed about end of life issues in the early phase of dementia. Nurses should be aware of the cultural implications of surrogate decision‐making for Chinese family caregivers.