bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of two surgical techniques for acetabular reconstruction in total hip replacement for congenital hip disease
Authors: Hartofilakidis G. , Georgiades G. , Babis G. C. , Yiannakopoulos C. K. 
Published: June 2008

We have evaluated the results of total hip replacement in patients with congenital hip disease using 46 cemented all-polyethylene Charnley acetabular components implanted with the cotyloplasty technique in 34 patients (group A), and compared them with 47 metal-backed cementless acetabular components implanted without bone grafting in 33 patients (group B). Patients in group A were treated between 1988 and 1993 and those in group B between 1990 and 1995. The mean follow-up for group A was 16.6 years (12 to 18) and the mean follow-up for group B was 13.4 years (10 to 16). Revision for aseptic loosening was undertaken in 15 hips (32.6%) in group A and in four hips (8.5%) in group B. When liner exchange was included, a total of 13 hips were revised in group B (27.7%). The mean polyethylene wear was 0.11 mm/yr (0.002 to 0.43) and 0.107 mm/yr (0 to 0.62) for groups A and B, respectively. Polyethylene wear in group A was associated with linear osteolysis, and in group B with expansile osteolysis. In patients with congenital hip disease, when 80% cover of the implant can be obtained, a cementless acetabular component appears to be acceptable and provides durable fixation. However, because of the type of osteolysis arising with these devices, early exchange of a worn liner is recommended before extensive bone loss makes revision surgery more complicated.
Tribological and material analyses of retrieved alumina and zirconia ceramic heads correlated with polyethylene wear after total hip replacement
Authors: Kim Y.-H. , Kim J.-S. 
Published: June 2008

It has been suggested that the wear of ultra-high molecular weight polyethylene (UHMWPE) in total hip replacement is substantially reduced when the femoral head is ceramic rather than metal. However, studies of alumina and zirconia ceramic femoral heads on the penetration of an UHMWPE liner in vivo have given conflicting results. The purpose of this study was to examine the surface characteristics of 30 alumina and 24 zirconia ceramic femoral heads and to identify any phase transformation in the zirconia heads. We also studied the penetration rate of alumina and zirconia heads into contemporary UHMWPE liners. The alumina heads had been implanted for a mean of 11.3 years (8.1 to 16.2) and zirconia heads for a mean of 9.8 years (7.5 to 15). The mean surface roughness values of the explanted alumina heads (Ra 40.12 nm and Rpm 578.34 nm) were similar to those for the explanted zirconia heads (Ra 36.21 nm and Rpm 607.34 nm). The mean value of the monoclinic phase of two control zirconia heads was 1% (0.8% to 1.5%) and 1.2% (0.9% to 1.3%), respectively. The mean value of the monoclinic phase of 24 explanted zirconia heads was 7.3% (1% to 26%). In the alumina group, the mean linear penetration rate of the UMWPE liner was 0.10 mm/yr (0.09 to 0.12) in hips with low Ra and Rpm values (13.22 nm and 85.91 nm, respectively). The mean linear penetration rate of the UHMWPE liner was 0.13 mm/yr (0.07 to 0.23) in hips with high Ra and Rpm values (198.72 nm and 1329 nm, respectively). This difference was significant (p = 0.041). In the zirconia head group, the mean linear penetration rate of the UHMWPE liner was 0.09 mm/yr (0.07 to 0.14) in hips with low Ra and Rpm values (12.78 nm and 92.99 nm, respectively). The mean linear penetration rate of the UHMWPE liner was 0.12 mm/yr (0.08 to 0.22) in hips with high Ra and Rpm values (199.21 nm and 1381 nm, respectively). This difference was significant (p = 0.039). The explanted zirconia heads which had a minimal phase transformation had similar surface roughness and a similar penetration rate of UHMWPE liner as the explanted alumina head.
Exclusion of Polymorphisms in Carnosinase Genes (CNDP1 and CNDP2) as a Cause of Diabetic Nephropathy in Type 1 Diabetes
Authors: Wanic Krzysztof , Placha Grzegorz , Dunn Jonathon , Smiles Adam , Warram James H. , Krolewski Andrzej S. 
Published: June 2008

OBJECTIVES— Recently, an association was found between diabetic nephropathy and the D18S880 microsatellite, located in the carnosinase gene (CNDP1) on chromosome 18q. Alleles of this microsatellite encode for a variable number of leucine residues (from four to seven) in the leader peptide of the carnosinase precursor. The frequency of subjects homozygous for the five leucines was higher in control subjects than in case subjects in studies focusing on type 2 diabetic patients. To test whether this finding can be extended to type 1 diabetic patients, we carried out a comprehensive study on association between diabetic nephropathy and the D18S880 microsatellite and 21 additional SNPs that tagged the genomic region containing CNDP1 and CNDP2.
RESEARCH DESIGN AND METHODS— Overall, 1,269 Caucasian patients with type 1 diabetes were included in the study, including 613 patients with normoalbuminuria and a long duration of diabetes, 445 patients with persistent proteinuria, and 211 patients with end-stage renal disease (ESRD). All patients were genotyped for selected polymorphisms, the associations with diabetic nephropathy were tested by a χ2 test, and odds ratios were calculated.
RESULTS— We did not find any significant association between diabetic nephropathy and any examined genetic markers. The negative findings of the case-control study were supported further by negative findings obtained from the 6-year follow-up study of 445 patients with persistent proteinuria, during which 135 patients developed ESRD.
CONCLUSIONS— Our large, comprehensive study did not find an association between the D18S880 microsatellite or any other polymorphisms in the CNDP2–CNDP1 genomic region and susceptibility for diabetic nephropathy in type 1 diabetes.
Individual Dissolution of Single‐Walled Carbon Nanotubes by Using Polybenzimidazole, and Highly Effective Reinforcement of Their Composite Films
Authors: Okamoto Minoru , Fujigaya Tsuyohiko , Nakashima Naotoshi 
Published: June 2008

AbstractPolybenzimidazole (PBI) is shown to individually dissolve/disperse single‐walled carbon nanotubes (SWNTs) in N,N‐dimethylacetamide (DMAc), which is demonstrated by vis‐near IR absorption and photoluminescence spectroscopy and atomic force microscopy observations. By casting these dispersions, SWNTs/PBI composite films were successfully fabricated on substrates without any sign of macroscopic aggregation. The thermal stability and mechanical properties of the composite films were investigated using thermogravimetric analysis (TGA) and tensile tests, respectively, and it was found that, first, the addition of SWNTs to PBI does not deteriorate the thermal stability of the matrix film, and second, the mechanical properties of the PBI film were reinforced by ca. 50% with only 0.06 wt % addition of the SWNTs to the film without reducing the thermal stability of the PBI. Raman spectroscopy of the composite films revealed the existence of an interaction between the PBI and the SWNTs. The individual dissolution of the SWNTs and efficient reinforcement of the PBI are due to the π–π interaction between the PBI and the sidewalls of the SWNTs.
Effect of polymer properties on bubble growth in polymer–paperboard composites
Authors: Annapragada Sriram K. , Patterson Timothy F. , Banerjee Sujit 
Published: June 2008

AbstractFoamed paperboard is a composite material used in thermally insulated food packaging and beverage containers. The paperboard is sandwiched between a layer of low‐density polyethylene and a barrier layer, and the low‐density film is foamed through heating. The moisture inside the paperboard vaporizes and serves as the driving force for creating the foam. The bubble growth on the paper surface has been tracked with high‐speed photography. The number of generated bubbles has been found to depend on the number of pores on the surface of the paperboard; there is little or no dependence on the properties of the polymer, at least across the range of properties studied. In contrast, the thickness of the foam is relatively insensitive to the paperboard properties but has a strong dependence on the thickness of the initial polymer film, the nature of the polymer, and the speed at which it is extruded onto the paperboard. It is believed that some of these variations arise from differences in the degree of adhesion between the polymer and the paperboard. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Structure and mechanical properties of blends of poly(ε‐caprolactone) with a poly(amino ether)
Authors: Granado Ainhoa , Eguiazábal Jose I. , Nazábal Jon 
Published: June 2008

AbstractPoly(ε‐caprolactone) (PCL)/poly(amino ether) (PAE) blends were obtained by injection molding without any previous extrusion step in an attempt to (i) contribute to the knowledge of the relation between structure and mechanical properties in these type of blends composed of a rubbery and a glassy polymer and (ii) to find out to which extent are the PCL/PAE blends compatible, and therefore whether the biodegradability of PCL can be added as a characteristic of PAE‐based applications. PCL/PAE blends are composed of a crystalline PCL phase, a pure amorphous PCL phase, and a PAE‐rich phase where some PCL is present. The presence of some dissolved and probably unreacted PCL in the PAE‐rich phase led to a low interfacial tension as observed by the small size of the dispersed particles and the large interfacial area. The dependence on composition of both the modulus of elasticity and the yield stress of the blends was parallel to that of the orientation level. The elongation at break showed values similar to those of PAE in PAE‐rich blends, and was slightly synergistic in very rich PCL compositions; this behavior reflects a change in the nature of the matrix, from glassy to rubbery. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Synthesis, characterization, and DNA‐binding of chiral complexes Δ‐ and Λ‐[Ru(bpy)2(pyip)]2+
Authors: Shi Shuo , Yao Tian‐Ming , Geng Xiao‐Ting , Jiang Ling‐Feng , Liu Jie , Yang Qing‐Yuan , Ji Liang‐Nian 
Published: June 2008

AbstractNew chiral Ru(II) complexes Δ and Λ‐[Ru(bpy)2(pyip)](PF6)2 [(bpy = 2,2′‐bipyridine; pyip = (2‐(1‐pyrenyl)‐1H‐imidazo[4,5‐f] [1,10]phenanthroline] were synthesized and characterized by elemental analysis, 1H NMR, ESI‐MS, IR, and CD spectra. Their DNA‐binding properties were studied by means of UV–vis, emission spectra, CD spectra and viscosity measurements. A subtle but detectable difference was observed in the interaction of both enantiomer with CT‐DNA. Spectroscopy experiments indicated that each of these complexes could interact with the DNA. The DNA‐binding of the Δ‐enantiomer was stronger than that of Λ‐enantiomer. DNA‐viscosity experiments provided evidence that both Δ‐ and Λ‐[Ru(bpy)2(pyip)](PF6)2 bound to DNA by intercalation. At the same time, the DNA‐photocleavage properties of the complexes were investigated too. Under irradiation with UV light, Ru(II) complexes showed different efficiency of cleaving DNA. Chirality, 2009. © 2008 Wiley‐Liss, Inc.
Does life originate from a single molecule?
Authors: Fuß Werner 
Published: June 2008

AbstractLife did not emerge in a single step. In chemical evolution, the first formation of a self‐replicating molecule was probably one of the most critical bottlenecks, which was overcome only with a very low probability. If only one such event was successful, present‐day life originates from a single molecule. In this case, homochirality in DNA and RNA is explained almost without further assumptions. By contrast, the enantiomer excess, produced by the deterministic mechanisms suggested so far, is smaller than the statistical standard deviation, unless the postulated initial number of molecules is very—in some mechanisms unreasonably—large. A certain chiral nonuniformity of natural monosaccharides other than (deoxy)ribose supports the idea that homochirality originates not from such small molecules but from an early RNA‐like oligomer. This nonuniformity seems also hard to explain by any deterministic mechanism. Chirality, 2009. © 2008 Wiley‐Liss, Inc.
Highly enantioselective addition of terminal alkynes to aldehydes catalyzed by a new chiral β‐sulfonamide alcohol/Ti(OiPr)4/Et2Zn/R3N catalyst system
Authors: Qiu Li , Wang Quan , Lin Li , Liu Xiaodong , Jiang Xianxing , Zhao Qingyang , Hu Guowen , Wang Rui 
Published: June 2008

AbstractA new catalytic system, generated from the readily available and inexpensive β‐sulfonamide alcohol L*, Ti(OiPr)4, Et2Zn, and tertiary amine base (R3N), effectively catalyzes the enantioselective addition of various terminal alkynes including some quite challenging alkynes to aldehydes in good yields and excellent enantioselectivities. Up to 96% yield and >99% enantioselectivity were achieved with the use of N,N‐diisoproylethylamine (DIPEA) as an additive in this asymmetric addition. Chirality, 2009. © 2008 Wiley‐Liss, Inc.
Design and implementation of parallel approximate inverse classes using OpenMP
Authors: Giannoutakis Konstantinos M. , Gravvanis George A. 
Published: June 2008

AbstractA new parallel normalized optimized approximate inverse algorithm, based on the concept of antidiagonal wave pattern, for computing classes of explicitly approximate inverses, is introduced for symmetric multiprocessor systems. The parallel normalized explicit approximate inverses are used in conjunction with parallel normalized explicit preconditioned conjugate gradient schemes for the efficient solution of finite element sparse linear systems. The parallel design and implementation issues of the new algorithm are discussed and the parallel performance is presented using OpenMP. Copyright © 2008 John Wiley & Sons, Ltd.
RAVE: the resource‐aware visualization environment
Authors: Grimstead I. J. , Avis N. J. , Walker D. W. 
Published: June 2008

AbstractWe present the resource‐aware visualization environment (RAVE) project, from its inception and design phases, through implementation choices and final actual use cases. RAVE is a distributed, collaborative Grid‐enabled visualization environment that supports automated resource discovery across heterogeneous machines. RAVE runs as a background process using Web services, enabling us to share resources with other users rather than commandeering an entire machine. RAVE supports a wide range of machines, from hand‐held PDAs to high‐end servers with large‐scale stereoscopic, tracked displays. The local display device may render all, some or none of the data set remotely, depending on its capability and present loading, utilizing remote servers to assist where necessary. This enables scientists and engineers to collaborate from their desks, in the field, or in front of specialized immersive displays. Copyright © 2008 John Wiley & Sons, Ltd.
The Neutralizer: a self‐configurable failure detector for minimizing distributed storage maintenance cost
Authors: Yang Zhi , Dai Yafei , Li Xiaoming 
Published: June 2008

AbstractTo achieve high data availability or reliability in an efficient manner, distributed storage systems must detect whether an observed node failure is permanent or transient, and if necessary, generate replicas to restore the desired level of replication. Given the unpredictability of network dynamics, however, distinguishing permanent and transient failures is extremely difficult. Though timeout‐based detectors can be used to avoid mistaking transient failures as permanent failures, it is unknown how the timeout values should be selected to achieve a better tradeoff between detection latency and accuracy. In this paper, we address this fundamental tradeoff from several perspectives. First, we explore the impact of different timeout values on maintenance cost by examining the probability of their false positives and false negatives. Second, we propose a self‐configurable failure detector called the Neutralizer based on the idea of counteracting false positives with false negatives. The Neutralizer could enable the system to maintain a desired replication level on average with the least amount of bandwidth. We conduct extensive simulations using real trace data from a widely deployed peer‐to‐peer system and synthetic traces based on PlanetLab and Microsoft PCs, showing a significant reduction in aggregate bandwidth usage after applying the Neutralizer (especially in an environment with a low average node availability). Overall, we demonstrate that the Neutralizer closely approximates the performance of a perfect ‘oracle’ detector in many cases. Copyright © 2008 John Wiley & Sons, Ltd.
Time trends in obesity and eating disorders
Authors: Zachrisson Henrik Daae , Vedul‐Kjelsås Einar , Götestam K. Gunnar , Mykletun Arnstein 
Published: June 2008

AbstractObjective:Obesity is a well‐known risk factor for eating disorders, and has been increasing in the normal population over the last decades. This study examines whether the increase in obesity is followed by an increase in prevalence of eating disorders in the general female population.Method:We compared the prevalence of eating disorders and obesity in two nationally representative surveys in Norway in 1991 (n = 1,537) and 2004 (n = 1,467). Eating disorder diagnoses were obtained using the self‐report questionnaire survey for eating disorders (SEDs) at both time points.Results:The prevalence of overweight and obesity has doubled from 1991 to 2004, whereas the prevalence of eating disorders has been stable. Obesity was strongly associated with eating disorders both in 1991 and 2004.Conclusion:Despite the strong association between obesity and eating disorders, the increase in obesity is not followed by an increase in eating disorders. © 2008 by Wiley Periodicals, Inc. Int J Eat Disord 2008
Novel Furo‐pyridine Derivatives via Sonogashira Reactions of Functionalized Pyridines
Authors: Lechel Tilman , Dash Jyotirmayee , Brüdgam Irene , Reißig Hans‐Ulrich 
Published: June 2008

AbstractA series of 4‐pyridyl nonaflates was coupled with several terminal alkynes to efficiently provide new 4‐alkynyl‐substituted 3‐alkoxypyridine derivatives. Apt conditions were developed for their conversion into furo[2,3‐c]pyridines. Sonogashira reactions of 4‐alkoxy‐substituted 3‐pyridyl nonaflates allowed an access to regioisomeric furo[3,2‐c]pyridines. For both types of alkynyl‐substituted alkoxypyridinesan alternative method for cyclization employing iodine monochloride furnished iodinated furo[2,3‐c]‐ or furo[3,2‐c]pyridines, which can undergo a second palladium‐catalyzed step. Iodination of 4‐hydroxypyridine derivative 24 with iodine afforded a pentasubstituted pyridine which after Sonogashira reaction immediately undergoes a cyclization to furo‐pyridine 25. Thus, three different types of furo‐pyridines can be prepared starting from one precursor. Several compounds prepared are fluorescent and show strong Stokes shifts. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Is it a short‐memory, long‐memory, or permanently Granger‐causation influence?
Authors: Chen Wen‐Den 
Published: June 2008

AbstractExploring the Granger‐causation relationship is an important and interesting topic in the field of econometrics. In the traditional model we usually apply the short‐memory style to exhibit the relationship, but in practice there could be other different influence patterns. Besides the short‐memory relationship, Chen (2006) demonstrates a long‐memory relationship, in which a useful approach is provided for estimation where the time series are not necessarily fractionally co‐integrated. In that paper two different relationships (short‐memory and long‐memory relationship) are regarded whereby the influence flow is decayed by geometric, or cutting off, or harmonic sequences. However, it limits the model to the stationary relationship. This paper extends the influence flow to a non‐stationary relationship where the limitation is on −0.5 ≤ d ≤ 1.0 and it can be used to detect whether the influence decays off (−0.5 ≤ d < 0.5) or is permanent (0.5 ≤ d ≤ 1.0). Copyright © 2008 John Wiley & Sons, Ltd.
Pore Size Distribution and Water Uptake in Hydrocarbon and Perfluorinated Proton‐Exchange Membranes as Studied by NMR Cryoporometry
Authors: von Kraemer S. , Sagidullin A. I. , Lindbergh G. , Furó I. , Persson E. , Jannasch P. 
Published: June 2008

AbstractSulfonated polysulfone (sPSU) membranes were analysed by nuclear magnetic resonance (NMR) cryoporometry, conventional gravimetric water uptake measurements as well as by differential scanning calorimetry (DSC). NMR cryoporometry is based on the relation between the pore size and the melting point depression of the pore‐filling liquid, i.e. water in fuel cell membranes; thus providing a relation between the amount of molten water and the temperature shift, i.e. the pore size, in hydrated membranes. An sPSU membrane with high ion‐exchange capacity (IEC 1.45 mequiv. g–1) possessed a significant amount of large pores after hydrothermal pre‐treatment at 80 °C, which was related to its high hydrophilicity and low resistance towards swelling. An sPSU membrane with low IEC (0.95 mequiv. g–1) showed a significant fraction of small pores (r ∼ 1 nm) after hydrothermal pre‐treatment at 80 °C, implying a controlled water uptake of the membrane. NMR cryoporometry was also carried out on Nafion membranes, the results were found to be in agreement with the water uptake measurements and revealed a pore size distribution peak at r ∼ 1 nm. The NMR cryoporometry, gravimetric water uptake and DSC results are also discussed in terms of the state of the water and methodological differences.
Evaluation of automated brain MR image segmentation and volumetry methods
Authors: Klauschen Frederick , Goldman Aaron , Barra Vincent , Meyer‐Lindenberg Andreas , Lundervold Arvid 
Published: June 2008

AbstractWe compare three widely used brain volumetry methods available in the software packages FSL, SPM5, and FreeSurfer and evaluate their performance using simulated and real MR brain data sets. We analyze the accuracy of gray and white matter volume measurements and their robustness against changes of image quality using the BrainWeb MRI database. These images are based on “gold‐standard” reference brain templates. This allows us to assess between‐ (same data set, different method) and also within‐segmenter (same method, variation of image quality) comparability, for both of which we find pronounced variations in segmentation results for gray and white matter volumes. The calculated volumes deviate up to >10% from the reference values for gray and white matter depending on method and image quality. Sensitivity is best for SPM5, volumetric accuracy for gray and white matter was similar in SPM5 and FSL and better than in FreeSurfer. FSL showed the highest stability for white (<5%), FreeSurfer (6.2%) for gray matter for constant image quality BrainWeb data. Between‐segmenter comparisons show discrepancies of up to >20% for the simulated data and 24% on average for the real data sets, whereas within‐method performance analysis uncovered volume differences of up to >15%. Since the discrepancies between results reach the same order of magnitude as volume changes observed in disease, these effects limit the usability of the segmentation methods for following volume changes in individual patients over time and should be taken into account during the planning and analysis of brain volume studies. Hum Brain Mapp, 2009. © 2008 Wiley‐Liss, Inc.