bluuebunny/crossref_metadata_2025_split huggingface dataset:
Population spatial structuring on the feeding grounds in North Atlantic humpback whales (Megaptera novaeangliae)
Authors: Stevick P. T. , Allen J. , Clapham P. J. , Katona S. K. , Larsen F. , Lien J. , Mattila D. K. , Palsbøll P. J. , Sears R. , Sigurjónsson J. , Smith T. D. , Vikingsson G. , Øien N. , Hammond P. S. 
Published: June 2006

AbstractPopulation spatial structuring among North Atlantic humpback whalesMegaptera novaeangliaeon the summer feeding grounds was investigated using movement patterns of identified individuals. We analysed the results from an intensive 2‐year ocean‐basin‐scale investigation resulting in 1658 individuals identified by natural markings and 751 individuals by genetic markers supplemented with data from a long‐term collaborative study with 3063 individuals identified by natural markings. Re‐sighting distances ranged from <1 km to >2200 km. The frequencies (F) of re‐sighting distances (D) observed in consecutive years were best modelled by an inverse allometric function (F=6631D−1.24,r2=0.984), reflecting high levels of site fidelity (median re‐sighting distance <40 km) with occasional long‐distance movement (5% of re‐sightings >550 km). The distribution of re‐sighting distances differed east and west of 45°W, with more long‐distance movement in the east. This difference is consistent with regional patterns of prey distribution and predictability. Four feeding aggregations were identified: the Gulf of Maine, eastern Canada, West Greenland and the eastern North Atlantic. There was an exchange rate of 0.98% between the western feeding aggregations. The prevalence of long‐distance movement in the east made delineation of possible additional feeding aggregations less clear. Limited exchange between sites separated by as little as tens of kilometres produced lower‐level structuring within all feeding aggregations. Regional and temporal differences in movement patterns reflected similar foraging responses to varying patterns of prey availability and predictability. A negative relationship was shown between relative abundance of herring and sand lance in the Gulf of Maine and humpback whale movement from the Gulf of Maine to eastern Canada.
Burrow architecture and burrowing dynamics of the endangered Namaqua dune mole rat (Bathyergus janetta) (Rodentia: Bathyergidae)
Authors: Herbst M. , Bennett N. C. 
Published: June 2006

AbstractThe Namaqua dune mole rat Bathyergus janetta is a solitary subterranean rodent that occurs in the arid and sandy regions of Namaqualand. The predictable winter rainfall and high diversity of geophytes, the predominant food resource, enables the mole rat to survive in this extreme environment. Burrowing and burrow system configuration were measured by observing mound production and the excavation of six mole rat burrow systems. A typical burrow system comprises nest chambers, food stores, defecation sites and bolt holes, which serve as a place of retreat when the animal is alarmed or threatened. Males tend to have linear‐shaped burrow systems, whereas the burrow systems of females are more reticulate. The linear nature of the male burrow system probably increases the home range used to search for potential mates. Burrow systems undergo constant excavation and re‐excavation within the home range. The average burrow length ranges from 71.2 to 165 m with a mean home range of 805.8±375.5 m2.
A Rasch Model Analysis of DSM‐IV Alcohol Abuse and Dependence Items in the National Epidemiological Survey on Alcohol and Related Conditions
Authors: Kahler Christopher W. , Strong David R. 
Published: June 2006

Background: Questions persist about the diagnoses of alcohol abuse and alcohol dependence as defined by Diagnostic and Statistical Manual of Mental Disorder, Fourth Edition (DSM‐IV). These questions center around the performance of individual alcohol use disorder (AUD) criteria and the nature of items used to assess them. In this study, we conduct in‐depth analyses of interview items used to assess alcohol abuse and dependence.Method: We conducted Rasch model analyses of responses to 33 items assessing alcohol abuse and dependence criteria in the National Epidemiological Survey on Alcohol and Related Conditions, a nationally representative sample of 34,550 participants. We also examined whether items performed differentially by gender, race/ethnicity, age, education, and time frame of assessment (i.e., past year vs lifetime).Results: A single latent dimension explained the vast majority of shared variance among the items. Abuse symptoms were not of consistently lower severity than dependence symptoms, and some were consistently prone to differential functioning across subgroups. Items related to tolerance also functioned differentially across subgroups especially in the comparison of past‐year symptoms between young adults (ages 18–24) and older adults. Items differed widely in their empirically estimated severity, even when they were intended to assess the same DSM‐IV criterion.Conclusions: The use of Rasch model analyses demonstrated the essential unidimensionality of AUD criteria and the lack of hierarchical ordering between abuse and dependence criteria, as well as potential sources of bias in the abuse diagnosis and the tolerance criterion. Results highlight that the prevalence and even the meaning of AUD criteria can differ substantially depending on the wording of items used to assess them. Implications for assessment of specific DSM criteria and for development of DSM‐V are discussed.
Meridional Propagation of Planetary-Scale Waves in Vertical Shear: Implication for the Venus Atmosphere
Authors: Imamura Takeshi 
Published: June 2006

Abstract
It is shown that planetary-scale waves are inherently accompanied by latitudinal momentum transport when they propagate vertically in vertically sheared zonal flows. Because of the dependence of the wave's latitudinal scale on the intrinsic phase speed, positive (negative) vertical shear should force prograde (retrograde) waves to focus equatorward and retrograde (prograde) waves to expand poleward in the course of upward propagation. Consequently, Eliassen–Palm (EP) flux vectors are tilted from the vertical and nonzero latitudinal momentum fluxes occur. The direction of momentum transport should always be equatorward (poleward) in positive (negative) vertical shear irrespective of the zonal propagation direction.
The idea was applied to upwardly propagating waves in the Venusian middle atmosphere, where vertical shear of strong midlatitude jets and equatorial superrotation exist. Numerical solutions showed that Kelvin and prograde inertio-gravity waves focus equatorward and mixed Rossby–gravity and Rossby waves expand poleward below the cloud top. The former is attributed primarily to the vertical shear of the superrotation, while the latter to the vertical shear beneath the midlatitude jets. Such characteristics of planetary-scale waves will cause angular momentum separation between high and low latitudes and, at least partly, contribute to the maintenance of the superrotation.
More men than women make mucosal IgA antibodies to Human papillomavirus type 16 (HPV-16) and HPV-18: a study of oral HPV and oral HPV antibodies in a normal healthy population
Authors: Marais Dianne J , Sampson Candice , Jeftha Anthea , Dhaya Dherendra , Passmore Jo-Ann S , Denny Lynette , Rybicki Edward P , Van Der Walt Eric , Stephen Lawrence XG , Williamson Anna-Lise 
Published: June 2006

Abstract

Background
We have previously shown the high prevalence of oral anti-human papillomavirus type 16 (HPV-16) antibodies in women with HPV-associated cervical neoplasia. It was postulated that the HPV antibodies were initiated after HPV antigenic stimulation at the cervix via the common mucosal immune system. The present study aimed to further evaluate the effectiveness of oral fluid testing for detecting the mucosal humoral response to HPV infection and to advance our limited understanding of the immune response to HPV.

Methods
The prevalence of oral HPV infection and oral antibodies to HPV types 16, 18 and 11 was determined in a normal, healthy population of children, adolescents and adults, both male and female, attending a dental clinic. HPV types in buccal cells were determined by DNA sequencing. Oral fluid was collected from the gingival crevice of the mouth by the OraSure method. HPV-16, HPV-18 and HPV-11 antibodies in oral fluid were detected by virus-like particle-based enzyme-linked immunosorbent assay. As a reference group 44 women with cervical neoplasia were included in the study.

Results
Oral HPV infection was highest in children (9/114, 7.9%), followed by adolescents (4/78, 5.1%), and lowest in normal adults (4/116, 3.5%). The predominant HPV type found was HPV-13 (7/22, 31.8%) followed by HPV-32 (5/22, 22.7%). The prevalence of oral antibodies to HPV-16, HPV-18 and HPV-11 was low in children and increased substantially in adolescents and normal adults. Oral HPV-16 IgA was significantly more prevalent in women with cervical neoplasia (30/44, 68.2%) than the women from the dental clinic (18/69, 26.1% P = 0.0001). Significantly more adult men than women displayed oral HPV-16 IgA (30/47 compared with 18/69, OR 5.0, 95% CI 2.09–12.1, P < 0.001) and HPV-18 IgA (17/47 compared with 13/69, OR 2.4, 95% CI 0.97–6.2, P = 0.04).

Conclusion
The increased prevalence of oral HPV antibodies in adolescent individuals compared with children was attributed to the onset of sexual activity. The increased prevalence of oral anti-HPV IgA in men compared with women was noteworthy considering reportedly fewer men than women make serum antibodies, and warrants further investigation.
Charcot-Marie-Tooth neuropathy type 2A: novel mutations in the mitofusin 2 gene (MFN2)
Authors: Engelfried Kathrin , Vorgerd Matthias , Hagedorn Michaela , Haas Gerhard , Gilles Jürgen , Epplen Jörg T , Meins Moritz 
Published: June 2006

Abstract

Background
Charcot-Marie-Tooth neuropathies are a group of genetically heterogeneous diseases of the peripheral nervous system. Mutations in the MFN2 gene have been reported as the primary cause of Charcot-Marie-Tooth disease type 2A.

Methods
Patients with the clinical diagnosis of Charcot-Marie-Tooth type 2 were screened using single strand conformation polymorphism (SSCP). All DNA samples showing band shifts in the SSCP analysis were amplified from genomic DNA and cycle sequenced.

Results
We analyzed a total of 73 unrelated patients with a clinical diagnosis of CMT 2. Overall, novel mutations were detected in 6 patients. c.380G>T (G127V), c.1128G>A (M376I), c.1040A>T (E347V), c.1403G>A (R468H), c.2113G>A (V705I), and c.2258_2259insT (L753fs).

Conclusion
We confirmed a significant role of mutations in MFN2 in the pathogenesis of Charcot-Marie-Tooth disease type 2.
Hospitalizations during the last months of life of nursing home residents: a retrospective cohort study from Germany
Authors: Ramroth Heribert , Specht-Leible Norbert , König Hans-Helmut , Brenner Hermann 
Published: June 2006

Abstract

Background
To describe hospitalisations of nursing home (NH) residents in Germany during their last months of life.

Methods
Retrospective cohort study on 792 NH residents in the Rhine-Neckar region in South-West Germany, newly institutionalized in the year 2000, who died until the study end (December 2001). Baseline variables were derived from a standardized medical examination routinely conducted by the medical service of the health care insurance plans in Germany. Information on hospitalisations and deaths was extracted form records of the pertinent health insurance plans.

Results
NH residents who died after NH stay of more than 1 year spent 5.8% of their last year of life in hospitals. Relative time spent in hospitals increased from 5.2% twelve months before death (N = 139 persons) to 24.1% in their last week of life (N = 769 persons). No major differences could be observed concerning age, gender or duration of stay in NH. Overall, 229 persons (28.9%) died in hospital. Among these, the last hospital stay lasted less than 3 days for 76 persons (31.9%). Another 25 persons (3.2%) died within three days after hospital discharge.

Conclusion
Our study indicates that proximity of death is the most important driver of health care utilization among NH residents. The relation of age or gender to health care expenditures seem to be weak once time to death is controlled for. Duration of NH stay does not markedly change rates of hospitalisation during the last months of life.
A case of phenytoin toxicity in a patient with advanced lung cancer
Authors: Jenkins Abi 
Published: June 2006

Phenytoin is an anti-convulsant drug commonly used to prevent seizures in patients with cerebral metastases. Phenytoin has complicated non-linear kinetics, is highly protein bound and has a small window between its therapeutic and toxic dose. This combination of factors means that small increases in dosage can all too quickly result in high plasma levels and toxic symptoms. Symptoms of phenytoin toxicity include: confusion, nystagmus, agitation, abnormal gait and hallucinations. This case report describes phenytoin toxicity in a patient receiving phenytoin 300mg three times a day for a number of weeks. The patient was admitted to the unit for terminal care, where his phenytoin levels were found to be very high. Phenytoin was withheld until levels returned to within the normal range. During this time the patient became orientated and many of his symptoms resolved.
Slip Velocity Direction Impacts Wear in Total Knee Arthropolasty
Authors: Schwenke T , Borgstede LL , Schneider E , Wimmer MA 
Published: June 2006

Abstract
Total knee arthroplasties are subjected to high slip velocities and constantly changing velocity vector directions, as they mimic the anatomical conditions of the natural joint. Together with fluid film thickness and applied load, the velocity difference between the two bodies defines the amount of energy that is induced into the contact. Particularly for polyethylene (PE), it is known that the angle describing the difference in motion direction is an important variable for material loss. In this study, a wheel-on-flat simulator scenario was used to apply a slip velocity vector with a constant magnitude and changing direction over the length of a polyethylene sample. The difference in vector orientation ranged from zero to 20.4°, while a constant axial load of 1600 N was applied, and the contact area was submersed in physiological testing fluid. After 500k cycles, the surface of the PE specimen was visually examined and scanned with a video-based measurement system to analyze the wear profile. Polishing was the predominant wear pattern, and minor striations were found in the end zone of the wear area. The wear depth increased with higher velocity angles—this relationship appeared to be linear. This study supports earlier publications that reported a correlation between cross-shear motion and wear. The presented experimental results will help in attempts to numerically simulate wear generation.
Scale Formation and Prevention in the Presence of Hydrate Inhibitors
Authors: Tomson M. B. , Kan A. T. , Fu G. , Al-Thubaiti M. , Shen Dong , Shipley Heather J. 
Published: June 2006

Summary
There is no accepted methodology to correlate the effects of hydrate inhibitors on scale formation as there is for electrolytes. Similarly, the effect of hydrate inhibitor on scale inhibition with common inhibitors is not well known. In this paper, a semi-empirical approach is proposed to correlate the effect of hydrate inhibitors on scale formation from experimental solubility measurements of halite, barite, gypsum, calcite, and carbonate equilibrium chemistry. The ion-cosolvent activity coefficients can be used directly in any solution speciation code to evaluate the effect of cosolvent on mineral scale formation. The validity of the equation has been tested between 4 and 50°C as well as between 1 and 6 M ionic strength. Working equations that can be used in gas and oil production to calculate the effect of cosolvents on scale formation are presented. Details about how to predict hydrate-inhibitor-induced scale formation and case studies that demonstrate the severity of methanol on scaling tendency are also discussed. Finally, barite nucleation and kinetics are studied in the presence and absence of methanol. A semi-empirical equation to predict the nucleation time is proposed. Preliminary studies of scale-inhibitor efficiency in the presence of methanol are also discussed. At high methanol concentration, scale inhibition may not be possible because of precipitation of metal-inhibitor salt. Glycols have a less adverse effect than methanol on both mineral scale formation and inhibition.
Reservoir Characterization During Underbalanced Drilling (UBD): Methodology and Active Tests
Authors: Vefring Erlend H. , Nygaard Gerhard , Lorentzen Rolf Johan , Nævdal Geir , Fjelde Kjell Kåre 
Published: June 2006

Summary
Two methods for characterizing reservoir pore pressure and reservoir permeability during UBD while applying active tests are presented and evaluated. Both methods utilize a fast, dynamic well fluid-flow model that is extended with a transient reservoir model. Active testing of the well is applied by varying the bottomhole pressure in the well during the drilling operations.
The first method uses the Levenberg-Marquardt optimization algorithm to estimate the reservoir parameters by minimizing the difference between measurements from the drilling process and the corresponding model states. The method is applied after the drilling process is finished, using all the recorded measurements. The second method is the ensemble Kalman filter, which simulates the drilling process using the dynamic model while drilling is performed, and updates the model states and parameters each time new measurements are available. Measurements are used that usually are available while drilling are used, such as pump rates, pump pressure, bottomhole pressure, and outlet rates.
The methods are applied to different cases, and the results indicate that active tests might improve the estimation results. The results also show that both estimation methods give useful results, and that the ensemble Kalman filter calculates these results during the UB operation.
Sand-Production Prediction: A New Set of Criteria for Modeling Based on Large-Scale Transient Experiments and Numerical Investigation
Authors: Nouri Alireza , Vaziri Hans , Belhaj Hadi , Islam Rafiqul 
Published: June 2006

Summary
This paper introduces a predictive tool that forecasts the drawdown associated with the onset of sanding as well as it predicts the sanding rate in real time. Experimental data on hollow cylinder samples (HCS) are used to support the validity of the numerical model.
Experiments on hollow-cylinder synthetic-sandstone specimens were conducted, involving real-time sand-production measurement under various conditions. A numerical approach was used for simulating the experimental results. The material behavior was simulated using an elastoplastic stress-strain relationship. The model simulated the interaction between fluid flow and mechanical deformation of the medium in predicting sand production. The model simulated strain softening of the material accompanied with shear-bands formation as well as tensile failure. In the post-disaggregation phase, additional features were considered, including allowing for the removal of the disaggregated elements that have satisfied the sanding criteria and, consequently, making the necessary adjustments to the size and properties of the domain under consideration. The model can be used for time-dependent analysis of wellbore stability as it undergoes disaggregation and sand production induced by depletion, drawdown, and water cut. Such numerical tools can be used in designing the completion by identifying the critical operational conditions associated with severe sanding over the lifetime of the wellbore.
The model showed a reasonable agreement with experimental results in terms of rock deformation and sanding rate. Further validation of the model against experimental and field data is necessary for its potential field applications.
An Experimental and Numerical Investigation of Crossflow Effects in Two-Phase Displacements
Authors: Cinar Y. , Jessen K. , Berenblyum R. , Juanes R. , Orr F. M. 
Published: June 2006

SummaryIn this paper, we present flow visualization experiments and numerical simulations that demonstrate the combined effects of viscous and capillary forces and gravity segregation on crossflow that occurs in two-phase displacements in layered porous media.We report results of a series of immiscible flooding experiments in 2D, two-layered glass bead models. Favorable mobility-ratio imbibition and unfavorable mobility-ratio drainage experiments were performed. We used pre-equilibrated immiscible phases from a ternary isooctane/isopropanol/water system, which allowed control of the interfacial tension (IFT) by varying the isopropanol concentration. Experiments were performed for a wide range of capillary and gravity numbers. The experimental results illustrate the transitions from flow dominated by capillary pressure at high IFT to flow dominated by gravity and viscous forces at low IFT. The experiments also illustrate the complex interplay of capillary, gravity, and viscous forces that controls crossflow. The experimental results confirm that the transition ranges of scaling groups suggested by Zhou et al. (1994) are appropriate/valid.We report also results of simulations of the displacement experiments by two different numerical techniques: finite-difference and streamline methods. The numerical simulation results agree well with experimental observations when gravity and viscous forces were most important. For capillary-dominated flows, the simulation results are in reasonable agreement with experimental observations.
Distributions stationnaires d'un système bonus–malus et probabilité de ruine
Authors: Dufresne Par François 
Published: June 2006

AbstractIt is shown how the stationary distributions of a bonus–malus system can be computed recursively. It is further shown that there is an intrinsic relationship between such a stationary distribution and the probability of ruin in the risk-theoretical model. The recursive algorithm is applied to the Swiss bonus–malus system for automobile third-party liability and can be used to evaluate ruin probabilities.
A Credibility Model with Random Fluctuations in Delay Probabilities for the Prediction of IBNR Claims
Authors: Hesselager Ole , Witting Thomas 
Published: June 2006

AbstractWe consider a general credibility model for the prediction of IBNR-claims which allows for random fluctuations in the underlying delay distribution. Such fluctuations always bring about decreasing credibility. It is shown that even negative credibility is achieved for more substantial fluctuations in the delay distribution. Special attention is paid to the mixed Poisson case for claim numbers including the discussion of parameter estimation.
Mathematical Fun with the Compound Binomial Process
Authors: Gerber Hans U. 
Published: June 2006

AbstractThe compound binomial model is a discrete time analogue (or approximation) of the compound Poisson model of classical risk theory. In this paper, several results are derived for the probability of ruin as well as for the joint distribution of the surpluses immediately before and at ruin. The starting point of the probabilistic arguments are two series of random variables with a surprisingly simple expectation (Theorem 1) and a more classical result of the theory of random walks (Theorem 2) that is best proved by a martingale argument.