bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effects of viscosity on the axial motor pattern and kinematics of the African lungfish (Protopterus annectens) during lateral undulatory swimming
Authors: Horner Angela M. , Jayne Bruce C. 
Published: May 2008

SUMMARYSeparate studies of terrestrial and aquatic locomotion are abundant, but research addressing locomotion in transitional environments (e.g. mud) is scant. The African lungfish (Protopterus annectens) moves in a gradation of water to mud conditions during seasonal droughts, and breathes air. Thus, the lungfish was an ideal organism for our study to determine the effects of a wide range of viscosities on lateral undulatory swimming and to simulate some of the muddy conditions early tetrapods may have encountered. Regardless of viscosity, several aspects of lungfish swimming were similar to those of other swimming vertebrates including: posteriorly propagated muscle activity that was unilateral and alternated between the left and right sides at each longitudinal location, and posterior increases in the amount of bending, the amplitude of muscle activity and the timing differences between muscle activity and bending. With increased viscosity (1–1000 cSt),significant increases occurred in the amount of lateral bending of the vertebral column and the amplitude of muscle activity, particularly in the most anterior sites, but the distance the fish traveled per tail beat decreased. The magnitude of the phase shift between EMG onset relative to bending increased by as much as 13% of a cycle with increased viscosity, so that the muscles were increasingly active during lengthening rather than shortening. Therefore, with increased viscosity the relationship between axial muscle activity and bending in the lungfish became more dissimilar rather than converging on the motor pattern used by other ectothermic vertebrates when undulating in fully terrestrial environments.
The landing–take-off asymmetry of human running is enhanced in old age
Authors: Cavagna G. A. , Legramandi M. A. , Peyré-Tartaruga L. A. 
Published: May 2008

SUMMARYThe landing–take-off asymmetry of running was thought to derive from,or at least to be consistent with, the physiological property of muscle to resist stretching (after landing) with a force greater than it can develop during shortening (before take-off). In old age, muscular force is reduced,but the deficit in force is less during stretching than during shortening. The greater loss in concentric versus eccentric strength with aging led us to hypothesize that older versus younger adults would increase the landing–take-off asymmetry in running. To test this hypothesis, we measured the within-step changes in mechanical energy of the centre of mass of the body in old and young subjects. The difference between the peaks in kinetic energy attained during the fall and during the lift of the centre of mass is greater in the old subjects. The difference between the time to lift and accelerate the centre of mass (positive work) and to absorb the same amount of energy during the downward displacement (negative work) is also greater in the old subjects. Both these findings imply a difference in force between stretching and shortening during the bounce, which is greater in the old subjects than in the young subjects. This is qualitatively consistent with the more asymmetric force–velocity relation found in aged muscle and supports, even if does not prove, the hypothesis that the landing–take-off asymmetry in running derives from the different response of muscle to stretching and shortening.
Gene expression changes in a zebrafish model of drug dependency suggest conservation of neuro-adaptation pathways
Authors: Kily Layla J. M. , Cowe Yuka C. M. , Hussain Osman , Patel Salma , McElwaine Suzanne , Cotter Finbarr E. , Brennan Caroline H. 
Published: May 2008

SUMMARYAddiction is a complex psychiatric disorder considered to be a disease of the brain's natural reward reinforcement system. Repeated stimulation of the`reward' pathway leads to adaptive changes in gene expression and synaptic organization that reinforce drug taking and underlie long-term changes in behaviour. The primitive nature of reward reinforcement pathways and the near universal ability of abused drugs to target the same system allow drug-associated reward and reinforcement to be studied in non-mammalian species. Zebrafish have proved to be a valuable model system for the study of vertebrate development and disease. Here we demonstrate that adult zebrafish show a dose-dependent acute conditioned place preference (CPP) reinforcement response to ethanol or nicotine. Repeated exposure of adult zebrafish to either nicotine or ethanol leads to a robust CPP response that persists following 3 weeks of abstinence and in the face of adverse stimuli, a behavioural indicator of the establishment of dependence. Microarray analysis using whole brain samples from drug-treated and control zebrafish identified 1362 genes that show a significant change in expression between control and treated individuals. Of these genes, 153 are common to both ethanol- and nicotine-treated animals. These genes include members of pathways and processes implicated in drug dependence in mammalian models, revealing conservation of neuro-adaptation pathways between zebrafish and mammals.
Occludin immunolocalization and protein expression in goldfish
Authors: Chasiotis Helen , Kelly Scott P. 
Published: May 2008

SUMMARYTight junctions (TJs) are an integral component of models illustrating ion transport mechanisms across fish epithelia; however, little is known about TJ proteins in fishes. Using immunohistochemical methods and Western blot analysis, we examined the localization and expression of occludin, a transmembrane TJ protein, in goldfish tissues. In goldfish gills,discontinuous occludin immunostaining was detected along the edges of secondary gill lamellae and within parts of the interlamellar region that line the lateral walls of the central venous sinus. In the goldfish intestine,occludin immunolocalized in a TJ-specific distribution pattern to apical regions of columnar epithelial cells lining the intestinal lumen. In the goldfish kidney, occludin was differentially expressed in discrete regions of the nephron. Occludin immunostaining was strongest in the distal segment of the nephron, moderate in the collecting duct and absent in the proximal segment. To investigate a potential role for occludin in the maintenance of the hydromineral balance of fishes, we subjected goldfish to 1, 2 and 4 weeks of food deprivation, and then examined the endpoints of hydromineral status,Na+,K+-ATPase activity and occludin protein expression in the gills, intestine and kidney. Occludin expression altered in response to hydromineral imbalance in a tissue-specific manner suggesting a dynamic role for this TJ protein in the regulation of epithelial permeability in fishes.
The relationship between shape of the skull and bite force in finches
Authors: van der Meij Maria A. A. , Bout Ron G. 
Published: May 2008

SUMMARY
In finches husking time is non-linearly related to the ratio of seed hardness to maximal bite force. Fringillids produce larger bite force and husk relatively hard seeds faster than estrildids of similar size. This is at least partly explained by their relatively larger jaw muscle mass and a difference in husking technique. However, the effect of differences in skull geometry on bite force is unclear. In this study differences in skull morphology that may contribute to the difference in bite force between fringillids and estrildids are analyzed. The shape of the skull was described by the 3D coordinates of a set of landmarks and, after eliminating size, the effect of differences in the shape of the skull on bite force was determined using a static force model. EMG recordings of jaw muscles during seed cracking were used to validate assumptions about the muscle activation patterns used for the static bite force model. The analysis shows that most of the variation in skull geometry is related to differences in size. Although the shape of the skull is highly convergent between fringillids and estrildids, the shape of the skull differs significantly between the two groups. A principal component analysis of the landmark coordinates shows several patterns of allometric shape changes, one of which is expressed more strongly in estrildids than in fringillids. Three characters dominate the effect of shape changes on bite force. Bite force increases with a more caudal position of the quadrate, a more downward inclined beak and a relatively short jugal and palatine. A more downward inclined beak is typically found in estrildids. The height of the upper bill and a number of other changes in skull shape have little effect on bite force. An estimate of the relative contributions of jaw muscle size and skull geometry to the difference in bite force between fringillids and estrildids suggests that the contribution of muscle size is much larger than the contribution of skull geometry.
Alternating egg-brooding behaviors create and modulate a hypoxic developmental micro-environment in Children's pythons (Antaresia childreni)
Authors: Stahlschmidt Zachary R. , DeNardo Dale F. 
Published: May 2008

SUMMARYParental care is a widespread and ecologically relevant adaptation known to enhance the developmental environment of offspring. Parental behaviors,however, may entail both costs and benefits for developing offspring. In Children's pythons (Antaresia childreni), we monitored both maternal egg-brooding behavior and intra-clutch oxygen partial pressure(PO2) in real-time to assess the effects of various brooding behaviors on PO2 in the clutch micro-environment at three stages of development. Furthermore, at the same developmental stages, we measured O2 consumption rates(V̇O2) of eggs at varying PO2 to determine their critical oxygen tension (i.e. the minimal PO2 that supports normal respiratory gas exchange) and to predict the impact that naturally brooded intra-clutch PO2 has on embryonic metabolism. At all three stages of development, a tightly coiled brooding posture created an intra-clutch PO2 that was significantly lower than the surrounding nest environment. Maternal postural adjustments alleviated this hypoxia, and the magnitude of such corrections increased with developmental stage. Mean intra-clutch PO2 decreased with stage of development,probably because of increasing egg V̇O2. Additionally, embryo critical oxygen tension increased with developmental stage. Together, these results suggest that python embryos are unable to maintain normal metabolism under brooded conditions during the final 10% of incubation. These results demonstrate that specific parental behaviors can impose obligatory costs to developing offspring and that balancing these behaviors can mediate deleterious consequences.
Safety assessment of underground vehicles passing over highly resilient straight track in the presence of a broken rail
Authors: Gonzalez F J , Suarez B , Paulin J , Fernandez I 
Published: May 2008

The current article presents the results of a research study that dealt with the simulation of vehicle—track interaction for a new slab track design, conceived to reduce noise and vibration levels transmitted to the neighbouring buildings. This design is mainly distinguished by its high elasticity and damping. A more elastic track, however, leads to greater rail deflections, which could affect the train's overall running safety. In this study, the derailment risk for trains running on slab track when encountering a broken rail has been evaluated. Two different types of rail fastening system with different elasticities have been analysed and compared. The results of this study will be considered in future track work projects. Up to now, the study has only been applied to straight track, even though the model is currently being extended to also study curved tracks. Numerical methods were used in order to simulate the dynamic behaviour of the train—track interaction. For that purpose, multi-body system (MBS) modelling techniques were combined with the techniques based on the finite-element method (FEM). MBS modelling was used for modelling the vehicle and FEM for simulating the elastic track. The simulation model was validated by comparing simulated results with experimental data obtained in field testing. During the simulations, various safety indices, characteristic of derailment risk, were analysed. The simulations realized at the maximum running velocity of 110 km/h showed a similar behaviour for several track types. When reducing the running speed, the safety indices worsened for both cases. Although the worst behaviour was observed for the track with a greater elasticity, in none of the simulations did a derailment occur when running over the broken rail.
N-Terminal Pro–B-Type Natriuretic Peptide Concentrations Predict the Risk of Cardiovascular Adverse Events from Antiinflammatory Drugs: A Pilot Trial
Authors: Brune Kay , Katus Hugo A , Moecks Joachim , Spanuth Eberhard , Jaffe Allan S , Giannitsis Evangelos 
Published: May 2008

Abstract
Background: We investigated whether higher concentrations of N-terminal pro–B-type natriuretic peptide (NT-proBNP) predicts cardiovascular adverse events (CV-AEs) in patients with osteoarthritis treated with antiinflammatory drugs.
Methods: NT-proBNP was measured in baseline samples from 433 patients enrolled in a prospective randomized study designed to test the therapeutic effect of a novel metalloproteinase inhibitor. We monitored CV-AEs and retrospectively investigated their relationship to the concomitant use of selective cyclooxygenase-2 inhibitors (coxibs), traditional nonsteroidal antiinflammatory drugs (tNSAIDs), and glucocorticoids. CV-AEs included myocardial infarction, stroke, new or worsening of preexisting arterial hypertension, congestive heart failure, and several less severe CV-AEs.
Results: We observed 82 mild to serious CV-AEs during an observational period of 200 days. The risk of such events was 1.95-fold higher in patients who were taking tNSAIDs, glucocorticoids, or coxibs (i.e., any inhibitor) and who had NT-proBNP concentrations ≥100 ng/L than in patients taking any inhibitor who had NT-proBNP values &lt;100 ng/L (P &lt; 0.05). Patients taking coxibs (alone or in addition to tNSAIDs or glucocorticoids) with baseline NT-proBNP values ≥100 ng/L had a 7.41-fold higher risk for CV-AEs than those with baseline values &lt;100 ng/L (P &lt; 0.01). Patients who were taking 2 or more antiinflammatory drugs and had NT-proBNP values ≥100 ng/L had a 3.74-fold higher risk for CV-AEs than those with NT-proBNP values &lt;100 ng/L (P &lt; 0.05). An NT-proBNP value &lt;100 ng/L was associated with negative predictive values of &gt;85% across all treatment groups.
Conclusions: NT-proBNP may be a useful marker for anticipating cardiovascular risk associated with the use of antiinflammatory drugs for osteoarthritis.
Plasma Dehydroepiandrosterone and Risk of Myocardial Infarction in Women
Authors: Page John H , Ma Jing , Rexrode Kathryn M , Rifai Nader , Manson JoAnn E , Hankinson Susan E 
Published: May 2008

AbstractBackground: In this study we prospectively evaluated the relationships between plasma concentrations of dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEA-S) and subsequent myocardial infarction in women.Methods: Using case-control sampling, we selected participants from the Nurses’ Health Study cohort. Blood samples were collected from 1989 to 1990 when the women were 43 to 69 years old. During follow-up through June 1998, 239 women were diagnosed with myocardial infarction (fatal and nonfatal). We matched cases 1:2 by age, cigarette smoking status, fasting status, and month of blood collection and used conditional logistic regression to adjust for potential confounders, including anthropometric factors and dietary intake.Results: Baseline median (10th, 90th percentiles) concentrations of DHEA were 17.1 (4.3, 46.7) nmol/L among women who subsequently developed myocardial infarction and 16.6 (6.1, 37.9) among controls. The risk of myocardial infarction increased with plasma concentrations of DHEA and its sulfate. Women in the highest DHEA quartile had a rate ratio (RR) of 1.27 (95% CI 0.92–1.74, P for trend = 0.008) for myocardial infarction compared with those in the lowest quartile, after adjusting for covariates. The results did not vary significantly by menopausal status, postmenopausal estrogen therapy, fasting status, or age at time of blood collection. Similar relationships between concentrations of DHEA-S and risk were observed, with an RR of 1.58 (95% CI 1.13–2.21; P for trend = 0.06) for myocardial infarction in the highest vs lowest quartile.Conclusions: We observed a modest positive relationship between plasma concentrations of DHEA and its sulfate and the risk of subsequent myocardial infarction among predominantly postmenopausal women.
Factors Affecting Accuracy of Stream Channel Slope Estimates Derived from Geographical Information Systems
Authors: Neeson Thomas M. , Gorman Ann Marie , Whiting Peter J. , Koonce Joseph F. 
Published: May 2008

Abstract
Stream channel slope is often a critical component of geographical information systems (GIS)-based models of preferred habitat of aquatic species, but the relative accuracy of various GIS slope derivation methods is not well established. We examined the accuracy of GIS-derived stream slopes for a set of stream reaches in Idaho and Ohio. We also used the Ohio data set to examine in more detail the effects of stream reach length, source of GIS file representing the stream path (“shapefile”), and digital elevation model (DEM) resolution on the accuracy of GIS-derived slopes. The accuracy of GIS-derived slopes in the Ohio dataset improved with increasing reach length, but we could not draw any consistent conclusions about the effect of DEM resolution or shapefile. We present a simple and efficient method for improving GIS-derived slopes by identifying probable elevation errors in the GIS-derived longitudinal stream profiles. The resulting derived slopes were improved in all cases; the slopes derived by using a 10-m DEM and a manually traced stream shapefile were the most accurate. We demonstrate how our results can be used to evaluate the feasibility of implementing a GIS-based habitat model of sea lampreys Petromyzon marinus.
Cryopreservation of Sperm from Endangered Pallid Sturgeon
Authors: Wayman William R. , Looney Gregory L. , Holm Robert J. , Tiersch Terrence R. 
Published: May 2008

Abstract
We sought to develop sperm cryopreservation methods for the pallid sturgeon Scaphirhynchus albus, a federally listed endangered species. Males were injected with synthetic luteinizing hormone releasing hormone at 50 μg/kg of body weight. After 24 h, sperm were collected, diluted at a ratio of 1:4 (sperm : extender) with Hanks' balanced salt solution (HBSS; diluted to 100 milliosmoles/kg), and kept refrigerated until use. Methanol was used as a cryoprotectant at concentrations of 5, 10, and 15% (volume per volume) and was mixed 1:1 with HBSS before the experiment to reduce effects of initial mixing. Sperm were mixed with the cryoprotectant, loaded into 0.5-mL straws, packed into goblets (5 straws/goblet), and placed in the lower position on aluminum canes. Motility was estimated before freezing to determine the effects of cryoprotectant toxicity; there was no significant difference in motility at the concentrations tested (P = 0.4828). After a 2-min equilibration period, the canes were lowered into a nitrogen vapor shipping dewar. The cooling rate of −22°C/min was recorded by thermocouples inserted into 0.5-mL straws filled with extender and cryoprotectant. After 1 year of storage in liquid nitrogen, straws were thawed in a 40°C water bath for 9 s and motility was estimated. Postthaw motility did not differ among the cryoprotectants tested (P = 0.4880). Each sample was used to fertilize approximately 150 eggs, which were incubated at 21°C. Sperm that was cryopreserved with 5% or 10% methanol produced eggs with significantly higher hatch rates did sperm cryopreserved with 15% methanol (P &lt; 0.0001). The development of techniques for cryopreserved sperm of pallid sturgeon allows for the creation of germplasm repositories that will aid in the recovery of this endangered species.
Traumatic Arteriovenous Malformation following Maxillary Le Fort I Osteotomy
Authors: Smith I. M. , Anderson P. J. , Wilks M. J. , David D. J. 
Published: May 2008

Objective: Complications following maxillary Le Fort I osteotomy are rare. The authors present the rare complication of an arteriovenous malformation following such a procedure in a 25-year-old woman with a cleft lip and palate that was treated successfully with radiologically guided embolization.
Presurgical Orthopedics and Satisfaction in Motherhood: A Randomized Clinical Trial (dutchcleft)
Authors: Prahl Charlotte , Prahl-Andersen Birte , Van't Hof Martin A. , Kuijpers-Jagtman Anne M. 
Published: May 2008

Objective: To study the effect of infant orthopedics on satisfaction in motherhood. Design: Prospective two-arm randomized controlled trial in parallel with three participating academic cleft palate centers. Treatment allocation was concealed and was performed by means of a computerized balanced allocation method. Setting: Cleft palate centers of Amsterdam, Nijmegen, and Rotterdam, the Netherlands. Patients: Two groups of infants with complete unilateral cleft lip and palate and no other malformations. Interventions: Group IO+ (n  =  27) wore passive maxillary plates during the first year of life, group IO− (n  =  27) did not. Main Outcome Measure(s): Mean satisfaction scores were obtained from completed questionnaires at 6, 24, and 58 weeks of age. A 4-point scale was used (1  =  very satisfactory to 4  =  very unsatisfactory). Results: The range of the mean scores for the individual items on the questionnaires for both groups ranged between 1.1 and 2.4. No differences were found between groups. Mothers appear to be satisfied in motherhood, least satisfied with the available time for themselves, and very satisfied with hugging and walking their babies. No differences were found between groups. Conclusions: Results from the present study show that infant orthopedics, with a passive plate during the first year of life, in children with a unilateral cleft lip and palate has no influence on the mothers’ satisfaction in motherhood.
Relapse Tendency in Maxillary Arch Width in Unilateral Cleft Lip and Palate Patients with Different Maxillary Arch Forms
Authors: Al-Gunaid Talat , Asahito Toshikazu , Yamaki Masaki , Hanada Kooji , Takagi Ritsuo , Ono Kazuhiro , Saito Isao 
Published: May 2008

Objective: The aim of this study was to investigate the relapse tendency in the maxillary dental arch widths in unilateral cleft lip and palate patients with different types of maxillary arch form. Subjects: Thirty-two unilateral cleft lip and palate patients treated by one-stage surgical palatal closure were included. The subjects were divided into three groups according to the types of the maxillary arch forms: group A, symmetrical arch form; group B, collapse of minor segment; group C, collapse of both segments. Methods: Using dental casts obtained at three different times, relapse in the intercanine, interpremolar, and intermolar widths in each group was assessed and differences between groups were investigated. Results: Patients in group A showed stable results in all measurements. Patients in group B showed posttreatment relapse in the intercanine width only, whereas patients in group C demonstrated significant posttreatment relapses in the interpremolar and intermolar widths. Comparison between groups showed more significant relapse in the interpremolar and intermolar widths of group C than in those of group B. Conclusion: The types of the maxillary arch forms in unilateral cleft lip and palate patients might play a stronger role in the stability of the maxillary dental arch widths after orthodontic treatment in patients with collapse of both segments and a severe degree of maxillary narrowness.