bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mitochondrial DNA analysis of horses recovered from a frozen tomb (Berel site, Kazakhstan, 3rd Century BC)
Authors: Keyser‐Tracqui C. , Blandin‐Frappin P. , Francfort H.‐P. , Ricaut F.‐X. , Lepetz S. , Crubézy E. , Samashev Z. , Ludes B. 
Published: April 2010

SummarySequence polymorphism of the mitochondrial DNA D‐loop was used to determine the genetic diversity of horses recovered from a Scythian princely tomb dating from the beginning of the 3rd century BC. Eight haplotypes were found among the 13 ancient horse samples tested. Phylogenetical analysis showed that these ancient horse's sequences, along with two Yakut ones, were distributed throughout the tree defined by modern horses’ sequences and are closely related to them. No clear geographical affiliation of the specimens studied was thus determined. Our work, among others, supports the very ancient origin of the matrilines in horses.
Assessing macroinvertebrate metrics for classifying acidified rivers across northern Europe
Authors: JANNICKE MOE S. , SCHARTAU ANN KRISTIN , BÆKKEN TORLEIF , McFARLAND BEN 
Published: April 2010

Summary1. The effects of acidification on ecological status of rivers in Northern Europe must be assessed according to the EU Water Framework Directive (WFD). Several acidification metrics based on macroinvertebrates already exist in different countries, and the WFD requires that they be comparable across northern Europe. Thus, we compiled macroinvertebrate monitoring data from the U.K. (n = 191 samples), Norway (n = 740) and Sweden (n = 531) for analysis against pH.2. We tested new and existing acidification metrics developed nationally and used within the Northern Geographical Intercalibration Group. The new metrics were based on the acidification sensitivity of selected species and are proposed as a first step towards a new common indicator for acidification for Northern Europe.3. Metrics were assessed according to responsiveness to mean pH, degree of nonlinearity in response and consistency in responses across countries. We used flexible, nonparametric regression models to explore various properties of the pressure–response relationships. Metrics were also analysed with humic content (total organic carbon above/below 5 mg L−1) as a covariate.4. Most metrics responded clearly to pH, with the following metrics explaining most of the variance: Acid Water Indicator Community, Number of ephemeropteran families, Medin's index, Multimetric Indicator of Stream Acidification and the new metric ‘Proportion of sensitive Ephemeroptera’.5. Most metrics were significantly higher in humic than in clear‐water rivers, suggesting smaller acidification effects in humic rivers. This result supports the proposed use of humic level as a typological factor in the assessment of acidification.6. Some potentially important effects could not be considered in this study, such as the additional effects of metals, episodic acidification and the contrasting effects of natural versus anthropogenic acidity. We advocate further data collection and testing of metrics to incorporate these factors.
Use of generalised dissimilarity modelling to improve the biological discrimination of river and stream classifications
Authors: LEATHWICK J. R. , SNELDER T. , CHADDERTON W. L. , ELITH J. , JULIAN K. , FERRIER S. 
Published: April 2010

Summary1. Classifications that group rivers and streams with similar ecological characteristics are used increasingly to underpin conservation and resource management planning. Uses include identifying systems that may respond similarly to human activities or management actions, setting guidelines and standards to manage human impacts, interpreting data from inventory (survey) and monitoring, and identifying priority sites for conservation management.2. Traditional approaches to river classification have been based mostly on delineating landscape units (ecoregions), often by grouping adjacent catchments having similar ecological character. However, use of this approach can be complicated by marked local heterogeneity of river systems. Instead, classifications may be more ecologically relevant if individual river or stream segments having similar environmental conditions are grouped together, independent of their geographic locations. The latter approach also allows the use of more rigorous classification procedures, including newly emerging techniques that optimise the ability of a classification to discriminate patterns in parallel sets of biological data.3. Here, we explore the use of one of these newer techniques, generalised dissimilarity modelling (GDM), an extension of generalised regression techniques, that defines an optimal set of transformations of candidate environmental predictors to maximise explanation of species turnover in site‐based biological data.4. Using two biological data sets describing the distributions of freshwater fish and macroinvertebrates and a candidate set of functionally relevant environmental variables, we used GDM to identify the variables, weightings and transformations that best explain biological dissimilarities across sites. We then used these as input to a multivariate classification of 567 000 river and stream segments throughout New Zealand. Weightings and transformations of these variables were also specified from the GDM analysis. The matrix of transformed environmental predictors was classified in a two‐stage process, using non‐hierarchical mediod clustering to define an initial set of 400 groups, with relationships between these groups then defined using hierarchical clustering.5. The resulting classification better discriminates sites with similar biological character than previous classifications, particularly at higher levels of classification detail. Key factors contributing to this success include the use of detailed, segment‐specific environmental variables, coherently accounting for the longitudinal connectivity inherent in rivers including its implications for the construction of biologically relevant predictors, and the use of a modelling technique (GDM) designed to specifically analyse biological turnover and its relationships with environment.
The importance of nutrient co‐limitation in regulating algal community composition, productivity and algal‐derived DOC in an oligotrophic marsh in interior Alaska
Authors: WYATT KEVIN H. , STEVENSON R. JAN , TURETSKY MERRITT R. 
Published: April 2010

Summary1. Compared to lakes and streams, we know relatively little about the factors that regulate algae in freshwater wetlands. This discrepancy is particularly acute in boreal regions, where wetlands are abundant and processes related to climate change (i.e. increased permafrost collapse and soil weathering) are expected to increase nutrient inputs into aquatic systems. To investigate how accelerated nutrient inputs might affect algal structure and function in northern boreal wetlands, we added nitrogen, phosphorus and silica to mesocosms in an oligotrophic marsh in interior Alaska.2. We conducted two in situ mesocosm enrichment experiments during consecutive summer growing seasons, each lasting 24 days. In 2007, we investigated the effects of +N, +P, +Si and +N+P+Si enrichment on benthic algal biomass (chlorophyll‐a, ash‐free dry mass, biovolume), chemistry (N : P ratio) and community composition. In 2008, we expanded our first experiment to investigate the effects +N+P, +N+Si, +P+Si and +N+P+Si on the same algal parameters as well as productivity (mg C m−2 h−1).3. In both experiments, we measured water‐column dissolved organic carbon (DOC) inside treatment enclosures and related changes in DOC to standing algal biomass.4. Benthic algal accrual did not increase following 24 days of enrichment with any nutrient alone or with P and Si together (+P+Si), but increased significantly with the addition of N in any combination with P and Si (+N+P, +N+Si, +N+P+Si).5. Algal productivity (20 mg C m−2 h−1) increased between three‐ and seven‐fold (57–127 mg C m−2 h−1) with the addition of N in combination with any other nutrient (+N+P, +N+Si, +N+P+Si). Water‐column DOC concentration was significantly higher inside N‐combination treatments compared to the control during each season, and DOC increased linearly with benthic algal biomass in 2007 (r2 = 0.89, P < 0.0001) and 2008 (r2 = 0.74, P < 0.0001).6. Taxonomic composition of the wetland algal community responded most strongly to N‐combination treatments in both seasons. In 2007, there was a significant shift from Euglena and Mougeotia in the control treatment to Chroococcus and Gloeocystis with +N+P+Si enrichment, and in 2008, a Mougeotia‐dominated community was replaced by Gloeocystis in the +N+P treatment and by Nitzschia in +N+Si and +N+P+Si treatments.7. Together, these data provide several lines of evidence for co‐limitation, and the central importance of N as a co‐limiting nutrient for the wetland algal community. Changes in algal dynamics with increased nutrient concentrations could have important implications for wetland food webs and suggest that algae may provide a functional link between increasing nutrient inputs and altered wetland carbon cycling in this region.
Inter‐regional comparison of land‐use effects on stream metabolism
Authors: BERNOT MELODY J. , SOBOTA DANIEL J. , HALL ROBERT O. , MULHOLLAND PATRICK J. , DODDS WALTER K. , WEBSTER JACKSON R. , TANK JENNIFER L. , ASHKENAS LINDA R. , COOPER LEE W. , DAHM CLIFFORD N. , GREGORY STANLEY V. , GRIMM NANCY B. , HAMILTON STEPHEN K. , JOHNSON SHERRI L. , MCDOWELL WILLIAM H. , MEYER JUDITH L. , PETERSON BRUCE , POOLE GEOFFREY C. , VALETT H. MAURICE , ARANGO CLAY , BEAULIEU JAKE J. , BURGIN AMY J. , CRENSHAW CHELSEA , HELTON ASHLEY M. , JOHNSON LAURA , MERRIAM JEFF , NIEDERLEHNER B. R. , O’BRIEN JONATHAN M. , POTTER JODY D. , SHEIBLEY RICHARD W. , THOMAS SUZANNE M. , WILSON KYM 
Published: April 2010

Summary1. Rates of whole‐system metabolism (production and respiration) are fundamental indicators of ecosystem structure and function. Although first‐order, proximal controls are well understood, assessments of the interactions between proximal controls and distal controls, such as land use and geographic region, are lacking. Thus, the influence of land use on stream metabolism across geographic regions is unknown. Further, there is limited understanding of how land use may alter variability in ecosystem metabolism across regions.2. Stream metabolism was measured in nine streams in each of eight regions (n = 72) across the United States and Puerto Rico. In each region, three streams were selected from a range of three land uses: agriculturally influenced, urban‐influenced, and reference streams. Stream metabolism was estimated from diel changes in dissolved oxygen concentrations in each stream reach with correction for reaeration and groundwater input.3. Gross primary production (GPP) was highest in regions with little riparian vegetation (sagebrush steppe in Wyoming, desert shrub in Arizona/New Mexico) and lowest in forested regions (North Carolina, Oregon). In contrast, ecosystem respiration (ER) varied both within and among regions. Reference streams had significantly lower rates of GPP than urban or agriculturally influenced streams.4. GPP was positively correlated with photosynthetically active radiation and autotrophic biomass. Multiple regression models compared using Akaike’s information criterion (AIC) indicated GPP increased with water column ammonium and the fraction of the catchment in urban and reference land‐use categories. Multiple regression models also identified velocity, temperature, nitrate, ammonium, dissolved organic carbon, GPP, coarse benthic organic matter, fine benthic organic matter and the fraction of all land‐use categories in the catchment as regulators of ER.5. Structural equation modelling indicated significant distal as well as proximal control pathways including a direct effect of land‐use on GPP as well as SRP, DIN, and PAR effects on GPP; GPP effects on autotrophic biomass, organic matter, and ER; and organic matter effects on ER.6. Overall, consideration of the data separated by land‐use categories showed reduced inter‐regional variability in rates of metabolism, indicating that the influence of agricultural and urban land use can obscure regional differences in stream metabolism.
‘If it is not recorded, it has not been done!’? consistency between nursing records and observed nursing care in an Italian hospital
Authors: De Marinis Maria Grazia , Piredda Michela , Pascarella Maria Chiara , Vincenzi Bruno , Spiga Fiorenza , Tartaglini Daniela , Alvaro Rosaria , Matarese Maria 
Published: April 2010

Aims.  The aim of this study is to evaluate the consistency between the care given to patients and that documented, by comparing care observations with nursing records and describing which interventions were reported and which were omitted.Background.  Assumptions have been made about the relationship between documentation and care actually delivered, but there is insufficient evidence on the relationship between the actual care given and its recording.Design.  Observational study of the care given, completed by interviews and retrospective survey of records.Methods.  Structured observation during day shifts in the first six days of admission of pre and postsurgical care provided to 21 consecutive patients undergoing major abdominal surgery and audit of their nursing records. Each observation was completed by short interviews to nurses to ensure observations validity.Results.  Only 40% of nursing activities observed were included in the nursing records (37% of the assessments and 45% of the interventions). This indicated that nurses carry out more activities than they report. Consistency between performed and recorded care decreased significantly during the days when a higher number of activities were performed. Consistency between recording and observation of assessment activities was 38% for physical needs and 0% for educational needs. Consistency was higher for the assessments of physical signs/symptoms and risk factors for complications compared to the assessment of basic needs and pain. Consistency was 47% for technical interventions and 3% for educational activities.Conclusions.  Nursing records were not found to be an adequate tool for quality care evaluation, because they did not include all the caring activities that the nurses had carried out.Relevance to clinical practice.  This study supports the need to identify documentation systems that are easy to complete. Moreover, nursing education should pay more attention to the competences in the field of holistic care and patient education.
Geochemistry and petrology of garnet‐bearing S‐type Shir‐Kuh Granite, southwest Yazd, Central Iran
Authors: Sheibi Mariyam , Esmaeily Dariush , Nédélec Ann , Bouchez Jean Luc , Kananian Ali 
Published: April 2010

AbstractThe Jurassic Shir‐Kuh granitoid batholith in Central Iran intrudes Lower Jurassic sandstones and shales. The batholith consists of three main facies: (i) a granodioritic facies to the north; (ii) a monzogranitic facies spread throughout the batholith; and (iii) a leucogranitic facies along the northwestern margin. The granodiorites are composed mainly of plagioclase, quartz, K‐feldspar, biotite, and some muscovite, garnet, cordierite, ilmenite, zircon, apatite, and monazite. This facies contains variable amounts of restite minerals which are mainly defined by calcic plagioclase cores and small aggregates of biotite. The monzogranites, with mineral assemblages similar to those in the granodiorites, range from relatively mafic (cordierite‐bearing) to felsic (muscovite‐rich) rocks. The leucogranites, exposed as small stock and dykes, consist mainly of quartz, K‐feldspar, and sodic plagioclase. The batholith is peraluminous, calc‐alkaline, and typical of S‐type, as indicated by Na2O content (2.74%), molecular Al2O3/(CaO + Na2O + K2O) (A/CNK) ratio (1.17), K2O/Na2O ratio (1.39), and isotopic data ([87Sr/86Sr]i = 0.715). The rocks are characterized by enrichment in large ion lithophile elements such as Rb, Th and K and depletion in high field strength elements such as Nb and Ti. Chondrite‐normalized rare earth element (REE) patterns are characterized by light rare earth element (LREE) enrichment, with values of (La/Yb)N between 4.5 and 19.53, unfractionated heavy rare earth element (HREE) with values of (Gd/Yb)N between 0.98 and 2.88, and a distinct negative Eu. The parental magma of the Shir‐Kuh Granite was derived from a plagioclase‐rich metasedimentary source (local anatexis of metagreywacke) in the crust, with heat input from mantle melt components. The separation of restite crystals from the primary melt followed by the fractional crystallization appears to have been an effective differentiation process in the batholith.
Chick starvation in yellow‐eyed penguins: Evidence for poor diet quality and selective provisioning of chicks from conventional diet analysis and stable isotopes
Authors: BROWNE TIFFANY , LALAS CHRIS , MATTERN THOMAS , Van HEEZIK YOLANDA 
Published: April 2010

AbstractThe link between poor reproductive success and diet was investigated in yellow‐eyed penguins Megadyptes antipodes, by assessing diet at two localities separated by about 30 km: the north coast of Stewart Island where breeding success is low (0.38–0.67 chicks per pair in recent years), and Codfish Island where breeding success is higher (0.96–1.51 chicks per pair), and relating this to published data from South Island localities, where average breeding success was 1.1 chicks per pair. Diet composition, meal sizes and energetic content of meals and prey were determined from stomach contents, and stable isotope analyses of chick down, fledgling feathers and adult blood provided information on diet throughout the fledging period. The high proportion of stomachs that were empty or lacked diagnostic remains reduced sample size considerably, and variability between samples reduced the power to detect significant differences in meal size, proportions of empty stomachs and prey diversity of meals. Energetic content of Stewart Island meals was less than Codfish Island meals, and there was a non‐significant trend for smaller meal sizes and reduced prey diversity among Stewart Island samples. Both localities had lower prey diversity and smaller meals than South Island penguins. Blue cod Parapercis colias accounted for 99% of prey biomass in Stewart Island and 70% in Codfish Island stomach samples, where 27% of prey biomass was opalfish Hemerocoetes monopterygius. Isotopic mixing models carried out on larger sample sizes indicated that opalfish comprised a large proportion of the diet at both locations, with adults selectively provisioning chicks with opalfish while feeding mainly on blue cod themselves. We suggest the large blue cod consumed by Codfish Island and Stewart Island penguins, larger than those consumed by South Island penguins, is difficult to transfer to chicks by regurgitation. Oyster dredging around Stewart Island may have reduced the availability and abundance of alternative prey to Stewart Island penguins.
Plant populations track rather than buffer climate fluctuations
Authors: Jongejans Eelke , De Kroon Hans , Tuljapurkar Shripad , Shea Katriona 
Published: April 2010

Ecology Letters (2010) 13: 736–743AbstractClimate change not only affects mean temperature and precipitation but also exacerbates temporal fluctuations in these conditions. However, we know relatively little about how species respond to such climate fluctuations, with respect to variation in vital rates (i.e. survival, growth and reproduction of individuals) and population fluctuations. We examine whether populations display evidence of buffering against environmental variation in one of two ways: (1) through negative covariances among vital rates, or (2) reduction of variation in those vital rates to which population growth is most sensitive. We analyse time series of demographic data for 40 plant species and show that there is no evidence for either of these mechanisms. In species in which there is evidence for vital rate covariation, positive covariances between reproduction and survival rates predominate, and tend to magnify the effect of variability. Increasing climate variability is therefore expected to increase population fluctuations and extinction risks.
Do the Joint British Society (JBS2) guidelines on prevention of cardiovascular disease with respect to plasma glucose improve risk stratification in the general population? Prospective cohort study
Authors: Brunner E. J. , Shipley M. J. , Marmot M. G. , Kivimaki M. , Witte D. R. 
Published: April 2010

Diabet. Med. 27, 550–555 (2010)AbstractAims  British guidelines on vascular disease prevention recommend adding a random (casual) blood glucose measurement to a lipid profile in those aged ≥ 40 years. To assess this recommendation, we compared the predictive value of a risk model based on the Framingham risk score alone to one which additionally included information on fasting blood glucose, with respect to incident coronary heart disease (CHD) over 11 years.Method  Men and women aged 40–63 years in Whitehall II were followed up for incident CHD: death/non‐fatal myocardial infarction; angina confirmed by doctor diagnosis or electrocardiogram (ECG) and all first events. Fasting blood glucose was specified as a continuous variable or categorized by World Health Organization (WHO) 1999 glycaemic status (normal glucose tolerance, impaired fasting glucose or newly diagnosed diabetes).Results  The hazard ratio for incident CHD was 1.10 (95%CI 1.09; 1.12) in men and 1.13 (1.10; 1.17) in women per percentage point increase in Framingham risk. The excess risk remained unchanged in models which added glycaemic status or continuous fasting glucose. The area under the receiver operating characteristic (ROC) curve for the Framingham score and incident coronary heart disease [0.70 (0.68; 0.73)] did not change when glycaemic status or fasting glucose was added to the prediction model. Reclassification with these modified models improved discrimination based on the Framingham score alone when glycaemic status was added, net reclassification improvement 2.4% (95% CI 0.2%; 4.6%), but not when fasting glucose was added.Conclusion  Better detection of unrecognized diabetes is a valuable consequence of including a random blood glucose in a vascular risk profile. Our results suggest that this strategy is unlikely to improve risk stratification for CHD.