bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sahlgrenska Academy Self-reported Cognitive Impairment Questionnaire (SASCI-Q) – a research tool discriminating between subjectively cognitively impaired patients and healthy controls
Authors: Eckerström Marie , Skoogh Johanna , Rolstad Sindre , Göthlin Mattias , Steineck Gunnar , Johansson Boo , Wallin Anders 
Published: December 2012

ABSTRACTBackground: Subjective cognitive impairment (SCI) is a potential early marker for actual cognitive decline. The cognitive manifestation of the SCI stage is, however, largely unknown. Self-report instruments developed especially for use in the SCI population are lacking, and many SCI studies have not excluded mild cognitive impairment and dementia. We developed and tested a patient-based questionnaire on everyday cognitive function aiming to discriminate between patients with subjective, but not objective, cognitive impairment and healthy controls.Methods: Individuals experiencing cognitive impairment were interviewed to generate a pool of items. After condensing to 97 items, we tested the questionnaire in 93 SCI patients seeking care at a memory clinic (age M = 64.5 years, Mini-Mental State Examination (MMSE) M = 29.0) and 50 healthy controls (age M = 69.6 years, MMSE M = 29.3). Further item reduction was conducted to maximize that remaining items would discriminate between SCI patients and controls, using a conservative α level and requiring medium to high effect sizes. Internal consistency reliability and convergent validity was subsequently examined.Results: Forty-five items discriminated between the groups, resulting in the Sahlgrenska Academy Self-reported Cognitive Impairment Questionnaire (SASCI-Q). Internal consistency was high and correlations to a single question on memory functioning were of medium to large sizes. Most remaining items were related to the memory domain.Conclusion: The SASCI-Q discriminates between SCI patients and healthy controls and demonstrates satisfying psychometric properties. The instrument provides a research method for examining SCI and forms a foundation for future examining which SCI symptoms predict objective cognitive decline. The cognitive manifestation of the SCI stage is mostly related to experiences of memory deficits.
Development and Evaluation of a Bioenergetics Model for Bull Trout
Authors: Mesa Matthew G. , Weiland Lisa K. , Christiansen Helena E. , Sauter Sally T. , Beauchamp David A. 
Published: December 2012

AbstractWe conducted laboratory experiments to parameterize a bioenergetics model for wild Bull Trout Salvelinus confluentus, estimating the effects of body mass (12–1,117 g) and temperature (3–20°C) on maximum consumption (Cmax) and standard metabolic rates. The temperature associated with the highest Cmax was 16°C, and Cmax showed the characteristic dome‐shaped temperature‐dependent response. Mass‐dependent values of Cmax (N = 28) at 16°C ranged from 0.03 to 0.13 g·g−1·d−1. The standard metabolic rates of fish (N = 110) ranged from 0.0005 to 0.003 g·O2·g−1·d−1 and increased with increasing temperature but declined with increasing body mass. In two separate evaluation experiments, which were conducted at only one ration level (40% of estimated Cmax), the model predicted final weights that were, on average, within 1.2 ± 2.5% (mean ± SD) of observed values for fish ranging from 119 to 573 g and within 3.5 ± 4.9% of values for 31–65 g fish. Model‐predicted consumption was within 5.5 ± 10.9% of observed values for larger fish and within 12.4 ± 16.0% for smaller fish. Our model should be useful to those dealing with issues currently faced by Bull Trout, such as climate change or alterations in prey availability.
Estimating Effective Sample Size for Monitoring Length Distributions: A Comparative Study of Georges Bank Groundfish
Authors: Zhang Yuying , Cadrin Steve X. 
Published: December 2012

AbstractBecause of the aggregative behavior of fish, effective sample size is more meaningful than total sample size for estimating the length distribution of a fish stock. We estimated the effective sample sizes for mean length distributions of six groundfish species from Georges Bank using data collected by a Study Fleet Program implemented by the School for Marine Science and Technology (SMAST) at the University of Massachusetts–Dartmouth. Both statistical and simulation methods were applied. Skewness and kurtosis were also used as proxies for length distributions. The statistical result suggests that the estimated effective sample size is much less than the number of fish measured in the initial SMAST Study Fleet Program, while the simulation method suggests that for most groundfish species reducing the total number of fish to 20% will not affect the variance, skewness, and kurtosis of the population length. For the SMAST Study Fleet Program, increasing the number of sampling stations can improve sampling precision better than increasing the number of fish measured within each station. This study helps to develop an optimal sampling design that balances the quality of the data collected and costs of the sampling effort.
Validating Back‐Calculation Models Using Population Data
Authors: Perez K. O. , Munch S. B. 
Published: December 2012

AbstractOtolith back‐calculation, an estimation of size and growth at some previous age, is a valuable and widely used method of tracking the traits of surviving individuals. Although numerous back‐calculation models have been developed, the accuracy of model prediction is rarely assessed before using a model on wild populations. Using the Atlantic SilversideMenidia menidia, we tested the precision of four commonly used back‐calculation models (body proportional hypothesis, modified Fry, biological intercept, and time‐varying growth). We calculated the moments of the observed length frequency distribution (mean, variance, skewness, and kurtosis) and compared them with the moments of the back‐calculated length frequency distribution predicted by each model. We also compared how the most accurate back‐calculation model changed under various scenarios of size‐selective mortality and found that bias in back‐calculation could not be explained by size‐selective mortality. The differences between functional forms over a wide range of fish sizes were slight for the biological intercept and modified Fry models, whereas the time‐varying growth and body proportional hypothesis models differed considerably. We found that all models performed well for at least one measure of accuracy. However, the modified Fry model was the most accurate overall when back‐calculating to the observed population moments.
Reproductive senescence in female Soay sheep: variation across traits and contributions of individual ageing and selective disappearance
Authors: Hayward Adam D. , Wilson Alastair J. , Pilkington Jill G. , Clutton‐Brock Tim H. , Pemberton Josephine M. , Kruuk Loeske E. B. 
Published: December 2012

Summary

Although senescence in reproductive success has been observed in a number of wild animal populations, longitudinal analyses determining the actual processes responsible for population‐level patterns of ageing, and in particular, the relative contributions of within‐individual senescence vs. selective mortality, are rare. Furthermore, many studies also only consider single traits in isolation, despite evidence that different aspects of physiology and fitness may show varying patterns of senescence.

We used data from an unmanaged population of Soay sheep on the islands of St Kilda, NW Scotland to analyse age‐related change in four aspects of female reproductive performance: annual fecundity, twinning rate and the maternally influenced offspring traits of lamb birth weight and early survival. We present the results of three analytical techniques, which attempt to disentangle the contributions of within‐individual ageing, selective mortality and terminal effects to the observed population‐level patterns of age‐specific change.

All four traits showed considerable age‐related change, but population‐level trajectories varied markedly across them. Population‐level patterns were underpinned by considerable within‐individual senescence including within‐individual terminal declines in performance occurring only in the final year of life. However, at the population level, these processes were also masked to some extent by selective disappearance (mortality) of poor breeders.

The contributions of individual‐level ageing and selective mortality to population‐level ageing patterns varied considerably between traits, as did the nature of individual‐level senescence. We did not observe detectable significant late‐life declines in all four traits: in particular, there was no evidence of senescence in twinning rate. The results indicate that senescence may not be ubiquitous across all aspects of reproductive performance within a population.
Propagule pressure, not fire or cattle grazing, promotes invasion of buffel grass Cenchrus ciliaris
Authors: Fensham Rod J. , Donald Sam , Dwyer John M. 
Published: December 2012

Summary

The invasion of exotic grasses into savannas is occurring globally. Despite threats to ecosystem processes and biodiversity, few studies have investigated factors that facilitate invasion success.

The abundance of the exotic perennial Cenchrus ciliaris buffel grass was assessed across woodland clearings at 46 sites in Queensland, Australia. The influence of fire and grazing on the invasion success were also examined experimentally within 18 sampling stations (including cattle grazed and ungrazed treatment pairs) with unburnt, low‐intensity and high‐intensity fire treatments.

Mixed‐effects logistic regressions suggest that the probability of buffel grass occurring in remnants was predominantly a function of the abundance of buffel grass in adjoining paddocks. The abundance of buffel grass in remnants was greater where the boundaries with clearings faced the prevailing wind adjacent to paddocks with high buffel grass abundance.

There was a significant positive association between buffel grass and tree canopies at approximately half of the sites, and the strength of this association was positively related to the amount of coarse sand in the surface soil. This association was interpreted as nutrient enrichment from litter fall on sandy infertile soils being a requirement for invasion. The invasion of buffel grass at the experimental site accelerated with above‐average rainfall after a prolonged drought, and invasion continued even after imposing all combinations of fire and grazing.

Cattle grazing modestly enhanced invasion, relative to the absence of grazing, but this difference was only significant without burning. The occurrence of fire in both the survey and experiment was not associated with enhanced buffel grass invasion.

Invasion of buffel grass may be inevitable over large areas of savanna, especially when abundant rainfall follows periods of drought. However, invasion will be minimized in areas where buffel grass has not been planted, areas without cattle grazing and in areas with low soil fertility.

Synthesis and applications. The invasion of buffel grass accelerates during abundant rainfall after drought and is enhanced by propagule pressure, dispersal trajectories and under trees, probably as a result of nutrient enrichment. Disturbance had little influence on invasion, and there is no support for fire‐promoted invasion as predicted by the grass–fire cycle theory.
Ranolazine Maintained Sinus Rhythm in a Patient with Refractory Symptomatic Atrial Fibrillation
Authors: Sossalla Samuel , Sohns Christian , Seegers Joachim , Lüthje Lars , Vollmann Dirk , Zabel Markus 
Published: December 2012

SummaryWe report on a patient who was treated with several antiarrhythmic drugs as well as different ablation strategies. Nevertheless, symptomatic atrial fibrillation always recurred until an off‐label use with ranolazine was started. We could demonstrate potent effects of ranolazine on atrial fibrillation in a “wash‐in wash‐out” situation. Although promising controlled studies are needed to investigate a potential role of ranolazine for the treatment of atrial fibrillation.
Longitudinal growth of very low birth weight neonates during first year of life and risk factors for malnutrition in a developing country
Authors: Mukhopadhyay Kanya , Mahajan Rama , Louis Deepak , Narang Anil 
Published: December 2012

AbstractAimsTo study growth of very low birth weight neonates (VLBW) during first year and identify risk factors for malnutrition.MethodsNeonates ≤34 weeks and ≤1500 g enrolled in a human milk fortification trial were prospectively followed till 1 year corrected age (CA). Anthropometry was plotted on WHO charts. Risk factors were compared between well nourished and underweight infants.ResultsOne hundred and thirty‐two, 127, 110, 99 and 101 neonates were followed at CA of 40 weeks, 3, 6, 9 and 12 months. Weight (Mean Z score −2.3 ± 1.2 to –1.7 ± 1.4; p = 0.005) and length (−2.1 ± 1.5 to –1.5 ± 1.3; p = 0.004) improved significantly, from 40 weeks to one year while head circumference declined (−0.92 ± 1.1 to –1.2 ± 1.1; p < 0.001). Incidence of underweight, stunting, microcephaly and wasting changed from 63%, 53%, 13% and 52% neonates at 40 weeks to 41%, 32%, 21% and 27% at one year. Growth between fortified and unfortified or small for gestational age (SGA) and appropriate for gestational age (AGA) groups were similar, while extremely low birth weight (ELBW) neonates showed poorer growth. Z score of weight at 3 months emerged as an independent predictor of malnutrition at one year.ConclusionVLBW neonates, especially the ELBW group remained growth retarded at CA of one year. Z score of weight at 3 months was a significant risk factor for malnutrition at one year.
Red blood cell transfusion is associated with increased rebleeding in patients with nonvariceal upper gastrointestinal bleeding
Authors: Restellini S. , Kherad O. , Jairath V. , Martel M. , Barkun A. N. 
Published: December 2012

SummaryBackgroundThere exists considerable practice variation and little evidence to guide red blood cell (RBC) transfusion in patients with nonvariceal upper gastrointestinal bleeding (NVUGIB). Studies in other critically ill cohorts suggest associations between transfusions and adverse patient outcomes.AimTo characterise any possible clinically‐relevant association between RBC transfusion following NVUGIB with rebleeding and mortality.MethodsObservational study utilising the Canadian Registry of patients with Upper Gastrointestinal Bleeding and Endoscopy (RUGBE). Multivariable logistic regression models were used to examine and quantify independent associations between RBC transfusion and clinical outcomes.ResultsOverall, 1677 patients were included (66.2 ± 16.8 years, 61.7% male, 2.5 ± 1.7 comorbid conditions, initial haemoglobin, 96.8 ± 27.2 g/L); 53.7% received RBC transfusions (2.9 ± 1.6 units of blood), 31.6% had haemodynamic instability, 5.1% fresh blood on rectal examination and 8.6% in the nasogastric tube aspirate. Endoscopic haemostasis was performed in 35.2%. Overall rebleeding (defined as continuous bleeding, rebleeding or surgery) and mortality rates were 17.9% and 5.4%, respectively. After adjusting for potential confounders, transfusion of RBC within 24 h of presentation was significantly and independently associated with an increased risk of rebleeding (OR: 1.8, 95% CI: 1.2–2.8), but not death (OR: 1.0, 95% CI: 0.6–1.8).ConclusionsThis study suggests an association between RBC transfusion following NVUGIB and subsequent rebleeding, after appropriate and extensive adjustment for confounding. Prospective randomised trial evidence is needed to identify the most efficacious and cost‐effective transfusional strategies in these patients.
Duration of vancomycin treatment for coagulase‐negative Staphylococcus sepsis in very low birth weight infants
Authors: Linder Nehama , Lubin Daniel , Hernandez Adriana , Amit Limor , Ashkenazi Shai 
Published: December 2012

AimVancomycin is widely used to treat late onset coagulase‐negative Staphylococcus (CoNS) sepsis in very low birth weight (VLBW) infants. Although vancomycin is associated with a risk of toxicity and bacterial resistance, the appropriate duration of use has not been established. This study sought to investigate the association between the duration of vancomycin therapy and clinical outcome in VLBW infants with CoNS sepsis.MethodsThe files of all VLBW infants treated for CoNS sepsis at a tertiary paediatric medical centre from 1995–2003 were reviewed for clinical data, laboratory variables and outcome. Only patients with two positive diagnostic blood cultures were included. The findings were analyzed by duration of vancomycin treatment after the last positive blood culture.ResultsThe study cohort included 126 infants, 48 treated for 5 days, 32 for 6–7 days, 31 for 8–10 days and 15 for >10 days. There were no differences among the groups in perinatal characteristics, central catheter dwell time, laboratory data including haematologic, renal and liver function tests, or rate of complications of prematurity. Five infants were diagnosed with infective endocarditis or aortic thrombi and were treated for >10 days. CoNS sepsis recurred in two infants (1.6%). No toxicity of vancomycin treatment was observed.ConclusionsIn VLBW infants with uncomplicated CoNS sepsis, treatment with vancomycin for 5 days after the last positive blood culture appears to be associated with a satisfactory outcome and no adverse effects. A well‐controlled prospective multicentre study is needed to confirm these findings.
A semi‐mechanistic absorption model to evaluate drug–drug interaction with dabigatran: application with clarithromycin
Authors: Delavenne Xavier , Ollier Edouard , Basset Thierry , Bertoletti Laurent , Accassat Sandrine , Garcin Arnauld , Laporte Silvy , Zufferey Paul , Mismetti Patrick 
Published: December 2012

AimThe aim of this study was to develop a PK/PD model to assess drug–drug interactions between dabigatran and P‐gp modulators, using the example of clarithromycin, a strong inhibitor of P‐gp.MethodsTen healthy male volunteers were randomized to receive in the first treatment period a single 300 mg dose of dabigatran etexilate (DE) and in the second treatment period 500 mg clarithromycin twice daily during 3 days and then 300 mg DE plus 500 mg clarithromycin on the fourth day, or the same treatments in the reverse sequence. Dabigatran plasma concentration and ecarin clotting time (ECT) were measured on 11 blood samples. Models were built using a non‐linear mixed effect modelling approach.ResultsThe best PK model was based on an inverse Gaussian absorption process with two compartments. The relationship between dabigatran concentration and ECT was implemented as a linear function. No continuous covariate was associated with a significant decrease in the objective function. The concomitant administration of clarithromycin induced a significant change only in DE bioavailability, which increased from 6.5% to 10.1% in the presence of clarithromycin. Clarithromycin increased peak concentration and AUC by 60.2% and 49.1% respectively.ConclusionThe model proposed effectively describes the complex PK of dabigatran and takes into account drug–drug interactions with P‐gp activity modulators, such as clarithromycin.
Strong Genetic Contribution to Peer Relationship Difficulties at School Entry: Findings From a Longitudinal Twin Study
Authors: Boivin Michel , Brendgen Mara , Vitaro Frank , Dionne Ginette , Girard Alain , Pérusse Daniel , Tremblay Richard E. 
Published: December 2012

This study assessed the genetic and environmental contributions to peer difficulties in the early school years. Twins' peer difficulties were assessed longitudinally in kindergarten (796 twins, Mage = 6.1 years), Grade 1 (948 twins, Mage = 7.1 years), and Grade 4 (868 twins, Mage = 10 years) through multiple informants. The multivariate results revealed that genetic factors accounted for a strong part of both yearly and stable peer difficulties. At the univariate level, the genetic contributions emerged progressively, as did a growing consensus among informants with respect to those who experienced peer difficulties. These results underline the need to intervene early and persistently, and to target the child and the peer context to prevent peer difficulties and their consequences.
Comparative phylogeography reveals deep lineages and regional evolutionary hotspots in the Mojave and Sonoran Deserts
Authors: Wood Dustin A. , Vandergast Amy G. , Barr Kelly R. , Inman Rich D. , Esque Todd C. , Nussear Kenneth E. , Fisher Robert N. 
Published: December 2012

AbstractAimWe explored lineage diversification within desert‐dwelling fauna. Our goals were (1) to determine whether phylogenetic lineages and population expansions were consistent with younger Pleistocene climate fluctuation hypotheses or much older events predicted by pre‐Pleistocene vicariance hypotheses, (2) to assess concordance in spatial patterns of genetic divergence and diversity among species and (3) to identify regional evolutionary hotspots of divergence and diversity and assess their conservation status.LocationMojave, Colorado, and Sonoran Deserts, USA.MethodsWe analysed previously published gene sequence data for twelve species. We used Bayesian gene tree methods to estimate lineages and divergence times. Within each lineage, we tested for population expansion and age of expansion using coalescent approaches. We mapped interpopulation genetic divergence and intra‐population genetic diversity in a GIS to identify hotspots of highest genetic divergence and diversity and to assess whether protected lands overlapped with evolutionary hotspots.ResultsIn seven of the 12 species, lineage divergence substantially predated the Pleistocene. Historical population expansion was found in eight species, but expansion events postdated the Last Glacial Maximum (LGM) in only four. For all species assessed, six hotspots of high genetic divergence and diversity were concentrated in the Colorado Desert, along the Colorado River and in the Mojave/Sonoran ecotone. At least some proportion of the land within each recovered hotspot was categorized as protected, yet four of the six also overlapped with major areas of human development.Main conclusionsMost of the species studied here diversified into distinct Mojave and Sonoran lineages prior to the LGM – supporting older diversification hypotheses. Several evolutionary hotspots were recovered but are not strategically paired with areas of protected land. Long‐term preservation of species‐level biodiversity would entail selecting areas for protection in Mojave and Sonoran Deserts to retain divergent genetic diversity and ensure connectedness across environmental gradients.
Family dynamics through time: brood reduction followed by parental compensation with aggression and favouritism
Authors: Shizuka Daizaburo , Lyon Bruce E. 
Published: December 2012

AbstractParental food allocation in birds has long been a focal point for life history and parent–offspring conflict theories. In asynchronously hatching species, parents are thought to either adjust brood size through death of marginal offspring (brood reduction), or feed the disadvantaged chicks to reduce the competitive hierarchy (parental compensation). Here, we show that parent American coots (Fulica americana) practice both strategies by switching from brood reduction to compensation across time. Late‐hatching chicks suffer higher mortality only for the first few days after hatching. Later, parents begin to exhibit parental aggression towards older chicks and each parent favours a single chick, both of which are typically the youngest of the surviving offspring. The late‐hatched survivors can equal or exceed their older siblings in size prior to independence. A mixed allocation strategy allows parents to compensate for the costs of competitive hierarchies while gaining the benefits of hatching asynchrony.