bluuebunny/crossref_metadata_2025_split huggingface dataset:
Orthopaedic thromboprophylaxis
Authors: Warwick D. , Dahl O. E. , Fisher W. D. 
Published: February 2008

Thromboprophylaxis remains a controversial subject. A vast amount of epidemiological and trial data about venous thromboembolism has been published over the past 40 years. These data have been distilled and synthesised into guidelines designed to help the practitioner translate this extensive research into ‘evidence-based’ advice. Guidelines should, in theory, benefit patient care by ensuring that every patient routinely receives the best prophylaxis; without guidelines, it is argued, patients may fail to receive treatment or be exposed to protocols which are ineffective, dangerous or expensive. Guidelines, however, have not been welcomed or applied universally. In the United States, orthopaedic surgeons have published their concerns about the thromboprophylaxis guidelines prepared by the American College of Chest Physicians. In Britain, controversy persists with many surgeons unconvinced of the risk/benefit, cost/benefit or practicality of thromboprophylaxis. The extended remit of the recent National Institute of Clinical Excellence thromboprophylaxis guidelines has been challenged. The reasons for this disquiet are addressed in this paper and particular emphasis is placed on how clinically-acceptable guidelines could be developed and applied.
Efavirenz-Induced Hypersensitivity Reaction Manifesting in Rash and Hepatitis in a Latino Male
Authors: Leung Jennifer M , O'Brien John G , Wong Hing Ka , Winslow Dean L 
Published: February 2008

Objective: To report a case of hypersensitivity manifesting in a rash, fever, and life-threatening hepatitis in a patient initiated on efavirenz therapy. Case Summary: A 30-year-old Latino male newly diagnosed with HIV was started on efavirenz-based highly active antiretroviral therapy (HAART) using tenofovir 300 mg, emtricitabine 200 mg, and efavirenz 600 mg once daily. Eleven days after beginning therapy, he developed a hypersensitivity reaction manifesting in rash and fever preceding severe drug-induced hepatitis. Liver enzyme peak values were aspartate transaminase 3410 U/L and alanine transaminase 2132 U/L. Hepatitis resolved with discontinuation of the HAART. The patient was rechallenged with tenofovir and emtricitabine one year later; no adverse reactions occurred. Discussion: The Naranjo probability scale demonstrated a probable relationship between this adverse reaction and efavirenz. A MEDLINE search (2004 to September 2007) revealed 2 cases of rash preceding hepatitis with the initiation of efavirenz. Both cases were in women; there were no prior reported cases of efavirenz hypersensitivity in men. Although the mechanism of this reaction is unknown, a few factors may have contributed to this reaction. The half-life and the auto-induction of efavirenz may explain the continued rise in liver enzymes and severe hepatitis that continued to occur once the drug was discontinued. Another cause that may have contributed is the metabolism of the medication. CYP2B6 is responsible for almost 90% of the clearance of efavirenz. Data from a recent pharmacokinetic study showed that efavirenz concentrations were higher in both black and Latino patients when compared with those of white patients. In addition, it is highly probable that this patient's liver function was impaired when transaminase levels peaked, resulting in decreased clearance of efavirenz. Conclusions: Although such a hypersensitivity reaction is rare, efavirenz is the most probable cause of the erythematous maculopapular rash and acute hepatitis in this patient. Monitoring of liver function in patients who present with a rash following initiation of efavirenz-based HAART is recommended. In addition, clinicians should exercise caution in patients presenting with rash, fever, and increased liver enzymes (>3 times the upper limit of normal or patient baseline). It is strongly recommended that efavirenz therapy be withheld in such cases and reevaluated once liver enzyme levels stabilize.
HLA DR-DQ Haplotypes and Genotypes and Type 1 Diabetes Risk
Authors: Erlich Henry , Valdes Ana Maria , Noble Janelle , Carlson Joyce A. , Varney Mike , Concannon Pat , Mychaleckyj Josyf C. , Todd John A. , Bonella Persia , Fear Anna Lisa , Lavant Eva , Louey Anthony , Moonsamy Priscilla ,   for the Type 1 Diabetes Genetics Consortium
Published: February 2008

OBJECTIVE—The Type 1 Diabetes Genetics Consortium has collected type 1 diabetic families worldwide for genetic analysis. The major genetic determinants of type 1 diabetes are alleles at the HLA-DRB1 and DQB1 loci, with both susceptible and protective DR-DQ haplotypes present in all human populations. The aim of this study is to estimate the risk conferred by specific DR-DQ haplotypes and genotypes.RESEARCH DESIGN AND METHODS:—Six hundred and seven Caucasian families and 38 Asian families were typed at high resolution for the DRB1, DQA1, and DQB1 loci. The association analysis was performed by comparing the frequency of DR-DQ haplotypes among the chromosomes transmitted to an affected child with the frequency of chromosomes not transmitted to any affected child.RESULTS—A number of susceptible, neutral, and protective DR-DQ haplotypes have been identified, and a statistically significant hierarchy of type 1 diabetes risk has been established. The most susceptible haplotypes are the DRB1*0301-DQA1*0501-DQB1*0201 (odds ratio [OR] 3.64) and the DRB1*0405-DQA1*0301-DQB1*0302, DRB1*0401-DQA1*0301-DQB*0302, and DRB1*0402-DQA1*0301-DQB1*0302 haplotypes (ORs 11.37, 8.39, and 3.63), followed by the DRB1*0404-DQA1*0301-DQB1*0302 (OR 1.59) and the DRB1*0801-DQB1*0401-DQB1*0402 (OR 1.25) haplotypes. The most protective haplotypes are DRB1*1501-DQA1*0102-DQB1*0602 (OR 0.03), DRB1*1401-DQA1*0101-DQB1*0503 (OR 0.02), and DRB1*0701-DQA1*0201-DQB1*0303 (OR 0.02).CONCLUSIONS—Specific combinations of alleles at the DRB1, DQA1, and DQB1 loci determine the extent of haplotypic risk. The comparison of closely related DR-DQ haplotype pairs with different type 1 diabetes risks allowed identification of specific amino acid positions critical in determining disease susceptibility. These data also indicate that the risk associated with specific HLA haplotypes can be influenced by the genotype context and that the trans-complementing heterodimer encoded by DQA1*0501 and DQB1*0302 confers very high risk.
Effects of climate change on the distribution of Iberian tree species
Authors: Benito Garzón Marta , Sánchez de Dios Rut , Sainz Ollero Helios 
Published: February 2008

Question: Will the predicted climate changes affect species distribution in the Iberian Peninsula?Location: Iberian Peninsula (Spain and Portugal).Methods: We modelled current and future tree distributions as a function of climate, using a computational framework that made use of one machine learning technique, the random forest (RF) algorithm. This algorithm provided good predictions of the current distribution of each species, as shown by the area under the corresponding receiver operating characteristics (ROC) curves. Species turnover, richness and the change in distributions over time to 2080 under four Intergovernmental panel on climate change (IPCC) scenarios were calculated using the species map outputs.Results and Conclusions: The results show a notable reduction in the potential distribution of the studied species under all the IPCC scenarios, particularly so for mountain conifer species such as Pinus sylvestris, P. uncinata and Abies alba. Temperate species, especially Fagus sylvatica and Quercus petraea, were also predicted to suffer a reduction in their range; also sub‐mediterranean species, especially Q. pyrenaica, were predicted to undergo notable decline. In contrast, typically Mediterranean species appeared to be generally more capable of migration, and are therefore likely to be less affected.
Sustained attention and serotonin: a pharmaco‐fMRI study
Authors: Wingen Marleen , Kuypers Kim P.C. , van de Ven Vincent , Formisano Elia , Ramaekers Johannes G. 
Published: February 2008

AbstractObjectiveEvidence suggests that stimulation of serotonergic function in healthy humans causes an impairment of sustained attention. The present study assessed the influence of increased serotonin levels on brain areas involved in sustained attention.MethodsTen healthy volunteers (5♀, 5♂) received the selective serotonin reuptake inhibitor (SSRI) escitalopram (20 mg) and placebo in a balanced, double blind, two‐way crossover design. Participants performed the Mackworth Clock Test to measure sustained attention during functional MRI measurements at 3 Tesla. Subjective measurements after pharmacological manipulation were conducted with the Bond and Lader Questionnaire.ResultsIndependent of treatment, brain areas associated with task performance on a sustained attention task were activated, including right prefrontal and parietal areas. After escitalopram administration, less activation was shown in the caudate nucleus, thalamus, and frontal areas. No effect of escitalopram was shown on behavioral data although subjective measurements showed decreased alertness after escitalopram.ConclusionsThe results of the current pharmaco‐functional magnetic resonance imaging (fMRI) study give a first indication of involvement of serotonin in sustained attention through modulating activation of selective brain areas including the thalamus and caudate nucleus. Possibly, these areas are involved in a subcortical network for sustained attention, but further research is necessary. Copyright © 2008 John Wiley & Sons, Ltd.
The role of calcium gluconate in electrochemical activation of titanium for biomimetic coating of calcium phosphate
Authors: Shibli S. M. A. , Mathai Suja 
Published: February 2008

AbstractSupersaturation of calcium and phosphate in the bath solution and activation of the metal substrate is essential for effective biomimetic growth of apatite on orthopedic implants. In this work, bioactivation of titanium surface was achieved by electrodeposition of a thin layer of calcium phosphate followed by an alkaline treatment to obtain pure hydroxyapatite crystals. The influence of calcium gluconate in the electrolyte solution was evaluated and optimized. Adhesive strength, thickness, structural, and surface characteristics were evaluated. A highly adhesive and uniform layer of hydroxyapatite was formed on titanium surface when the electrodeposition was carried out with an electrolyte solution‐containing calcium gluconate. The electrodeposited hydroxyapatite coatings were subjected for biomimetic growth in Kokubo's simulated body fluid (SBF) and Kokubo's modified SBF containing 1.5 times higher concentration of Ca. Biomimetic growth was also improved by the addition of calcium gluconate in the SBF solution. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res 2008
Chondrocytes culture in three‐dimensional porous alginate scaffolds enhanced cell proliferation, matrix synthesis and gene expression
Authors: Lin Yu‐Ju , Yen Chi‐Nan , Hu Yu‐Chen , Wu Yung‐Chih , Liao Chun‐Jen , Chu I‐Ming 
Published: February 2008

AbstractFor the limited availability of autologous chondrocytes, a cultured system for expansion in vitro until sufficient cells are obtained must be developed. These cells must maintain their chondrocyte phenotype in vitro as well as in vivo, following implantation to ensure that differentiated chondrocytes synthesize a normal hyaline cartilage matrix and not a fibro‐cartilage matrix. This study uses porous three‐dimensional (3‐D) alginate scaffolds within a perfusion system to culture low‐density (5 × 105 cells) primary porcine chondrocytes for 1–4 weeks to study their proliferation and differentiation. The results of RT–PCR reveal that most cells could maintain their differentiation state for up to 4 weeks of culturing. Chondrocytes proliferated to 3 × 107 cells after 4 weeks in culture. Alginate scaffolds induced the formation of chondrocyte clusters and stimulated the synthesis of matrix, which effects were evaluated using histology and electron microscopy. These findings demonstrate that culturing chondrocytes in alginate scaffolds may effectively prevent the dedifferentiation and improve autologous chondrocyte transplantation. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
Marketing and development out of poverty: introduction to the special issue
Authors: Carr Stuart C. , Rugimbana Robert O. 
Published: February 2008

Abstract

Reducing poverty by meeting the United Nations' Millennium Development Goals (MDGs) is an interdisciplinary undertaking, in which Marketing Science logically plays a role. The papers in this special issue cover a range of methods, from traditional consumer research experiments (on images of poverty, donation behaviour) and sample surveys on the credibility of celebrity marketing, to observational studies of community values and customs (on micro‐finance or agricultural enterprise). Consumers of aid appeals, celebrity lobbying and financial services—these methods reveal—are behaviourally complex. They are infused with contradictory, competing and complementary tendencies. Underlying those different tendencies however is a common but often overlooked thread. For poverty to be significantly reduced by 2015, attention needs to be paid not only to goals, that is to task but also towards understanding the human relationships in the poverty reduction market. Marketing practise and research can contribute to poverty reduction by helping build (1) perspective‐sharing, (2) accommodation to local needs and (3) appreciation of socio‐economic and socio‐cultural behavioural systems.

Copyright © 2008 John Wiley & Sons, Ltd.
Numerische Beulsicherheitsnachweise bei Schalenbeulfällen mit überkritischen Tragreserven
Authors: Schneider Werner 
Published: February 2008

AbstractFür viele beulgefährdete Schalenkonstruktionen liegen keine ausreichenden experimentellen Daten vor, um deren Tragfähigkeit abschätzen zu können. Der Eurocode EN 1993‐1‐6 bietet deshalb die Möglichkeit numerisch gestützter Beulsicherheitsnachweise. Als maßgebend für die Tragfähigkeit wird dabei die erste Instabilitätslast angesehen. Das Problem lokaler Instabilitäten und sogenannter überkritischer Tragreserven ist nur am Rand erwähnt, aber nicht anwendungsbereit geregelt. Im Beitrag werden die aus dieser Verengung des Versagensbegriffes resultierenden Probleme diskutiert und Vorschläge zu ihrer Überwindung unterbreitet.
A study on rotational effects and different stall delay models using a prescribed wake vortex scheme and NREL phase VI experiment data
Authors: Breton Simon‐Philippe , Coton Frank N. , Moe Geir 
Published: February 2008

AbstractUnderstanding of the stall delay phenomenon on wind turbines remains, to this day, incomplete. A correct modelling of this phenomenon, which results from three‐dimensional rotational effects, is essential in order to make reliable wind turbine simulations on the basis of two‐dimensional airfoil data, such as with the widely used blade element momentum method. The present study addresses this issue by testing six existing models intended to correct for stall delay effects, namely those developed by Snel et al., Chaviaropoulos and Hansen, Raj, Bak et al., Corrigan and Schillings and Lindenburg. For this purpose, the models are implemented into a lifting‐line‐prescribed wake vortex scheme. Forces along the blades as well as power and root flap bending moment in a head‐on flow configuration are predicted based on these models, and are compared to wind tunnel data from NREL's phase VI experiment. While load over‐prediction in the presence of stall is in general observed from the use of the different models, significant differences between the models are still seen. Local over‐prediction is generally seen in the tip region, while discrepancies are obtained, even at low wind speed, for the root flap bending moment. The results obtained are discussed in terms of deficiencies and strengths of the current correction schemes, and from there a basis is provided for the development of improved correction models. Copyright © 2008 John Wiley & Sons, Ltd.
The effects of prey species on food conversion efficiency and growth of an insectivorous lizard
Authors: Rich C. Nelson , Talent Larry G. 
Published: February 2008

AbstractLittle is known about the effects of different prey species on lizard growth. We conducted a 6‐week study to determine the relative effects of prey species on growth parameters of hatchling western fence lizards, Sceloporus occidentalis. Lizards were fed house cricket nymphs, Acheta domesticus, or mealworm larvae, Tenebrio molitor. The effects of prey species on growth were determined by measuring prey consumption, gross conversion efficiency of food [gain in mass (g)/food consumed (g)], gain in mass, and gain in snout–vent length. Lizards grew well on both the prey species. However, lizards that fed on crickets consumed a significantly higher percentage of their body mass per day than those fed mealworms. Nevertheless, lizards that consumed mealworms ingested significantly more metabolizable energy, had significantly higher food conversion efficiencies, significantly higher daily gains in mass, and significantly greater total growth in mass than lizards that fed on crickets. Zoo Biol 27:181–187, 2008. © 2008 Wiley‐Liss, Inc.
An ultrastructural study of the early cercarial development in Prosorhynchoides borealis (Digenea: Bucephalidae) with special reference to formation of the primitive epithelium
Authors: Podvyaznaya I.M. , Galaktionov K.V. 
Published: February 2008

AbstractPrimitive epithelium and outer tegumental layer formation during early cercarial development was studied in Prosorhynchoides borealis using electron microscopy. It demonstrated that germinal cells freely floating in the sporocyst body cavity divide to give rise to naked cell aggregates. These early embryos are highly irregular in outline and are composed of blastomeres differing in size and structure. In embryos consisting of about 12–14 cells a few (possibly only two) superficial macromeres become concave and produce thin extensions which envelop the embryonic mass before fusing to form a syncytial primitive epithelium. This primitive epithelium forms syncytial connections with underlying embryonic cells. Primordial tegumental cells become apparent in late germinal balls below the primitive epithelium. These cells expand and fuse to give rise to an embryonic nucleated tegument. The embryonic tegument is connected to peripheral embryonic cells by thin cytoplasmic bridges until the basement lamina is formed. Subsequently, the primitive epithelium is shed by the embryos and the nuclei in the embryonic tegument undergo pyknotic degeneration. These results are analysed and compared with data from studies on other trematode species and it is concluded that the primitive epithelium is derived from the embryo in at least the majority of digeneans.
The use of basic parameters for monitoring the haemodynamic effects of midazolam and ketamine as opposed to propofol during cardiac catheterization
Authors: Baysal Ayse , Polat Tugcin Bora , Yalcin Yalim , Celebi Ahmet 
Published: February 2008

AbstractObjectiveOur aim is to compare the haemodynamic and adverse effects of propofol versus the mixture of midazolam and ketamine as used in sedation for cardiac catheterization in children.MethodsIn a prospective randomized trial, we divided patients needing sedation into 72 receiving a mixture of midazolam and ketamine and 42 receiving propofol. Their ages ranged from 6 months to 12 years, and 1 year to 16 years, respectively. We collected data relative to heart rate, mean arterial pressure, respiratory rate, peripheral saturations of oxygen, and adverse effects. We assessed cyanotic patients to establish any relationship between the haemodynamic data and peripheral arterial saturations of oxygen.ResultsDemographic data, including age, gender, and weight, was not statistically different between the groups. In those receiving midazolam and ketamine, mean systemic arterial pressures before, and 30 minutes after, sedation were 64.3, with standard deviation of 9.8, and 62.5, with standard deviation of 10.2, millimetre of mercury (p equals to 0.237). Heart rates were 131.3, with standard deviation of 13.5, and 109.2, with standard deviation of 17.3 beats per minute, (p less than 0.001) whereas in those given propofol the comparable values were 71.2, with standard deviation of 14.4, and 53.6 with standard deviation of 9.7 millimetres of mercury (p less than 0.001), and 115.2, with standard deviation of 13.6, and 100.5 with standard deviation of 20.1 beats per minute (p less than 0.01), respectively. Mean systemic arterial pressures in the subgroups of cyanotic patients before and 30 minutes after sedation were 74.8, with standard deviation of 14.6, and 72.7, with standard deviation of 12.4 millimetres of mercury for those receiving midazolam and ketamine (p equals to 0.544), and heart rates were 119.3, with standard deviation of 12.2, and 104.6 with standard deviation of 16.1 beats per minute (p equals to 0.001). In those given propofol, the comparable values were 71.1 with deviation of 15.5 and 53.9 with deviation of 9.2 millimetres of mercury (p equals to 0.001), and 126.7 with deviation of 20.8 and 107.2 with deviation of 13.5 beats per minute (p equals to 0.001), respectively.ConclusionsIn cyanotic children, propofol used as a sedative agent during cardiac catheterization causes a decrease in mean arterial pressure and arterial desaturation. Ketamine produces more stable haemodynamic data in children with congenitally malformed hearts.
Constraints on unroofing rates in the High Himalaya, eastern Nepal
Authors: Hubbard Mary , Royden Leigh , Hodges Kip 
Published: February 2008

Thermobarometric data for samples across the Main Central thrust zone in eastern Nepal show an inversion in temperature but not in pressure. These data have been interpreted to represent a portion of the paleogeotherm at the time of Main Central thrust deformation. A 40Ar/39Ar age on hornblende (closure temperature (Tc)=500±50°C) constrains the timing of this deformation to be ∼21±0.2 Ma. The 40Ar/39Ar ages of other minerals (muscovite, Tc=350°C, age (t)=12.0±0.2 Ma; K‐feldspar, Tc=220°C, t=8.0±0.2 Ma) from the same location further constrain the cooling history of this region. Together the geochronologic and thermobarometric data yield an average unroofing rate of 1.2±0.6 mm/yr for the High Himalaya of eastern Nepal.Simple thermal models show that these geochronologic and thermobarometric data are consistent with a wide range of different initial geotherms, applied boundary conditions and magnitude of radiogenic heat production. The variation through time of the unroofing rates can only be poorly constrained, however. The unroofing histories were found to be largely insensitive to the details of the assumed initial geotherm, fairly sensitive to the magnitude of radiogenic heat production, and extremely sensitive to the nature of the boundary conditions applied below the fault zone. This study underscores the difficulty in constraining uplift histories on the basis of cooling rates even when thermobarometric data are available to supplement geochronologic constraints on the cooling history of the region.