bluuebunny/crossref_metadata_2025_split huggingface dataset:
Vaporization and Diffusion Studies on the Stability of Doped Lanthanum Gallates
Authors: Stanislowski M. , Peck D.‐H. , Woo S.‐K. , Singheiser L. , Hilpert K. , Schulz O. , Martin M. 
Published: June 2006

AbstractVaporization and diffusion determine the stability of doped lanthanum gallates under SOFC operating conditions. Systematic vaporization studies of Ga and other elements were carried out using the vapor transpiration method. It was shown that the Ga vaporization is controlled by diffusion from the bulk to the surface. Diffusion coefficientsDGaand vaporization coefficients αGawere determined by fitting the measured vaporization data to a vaporization model. Secondary phases formed as a result of the vaporization were detected. The influence of different doping levels of Sr, Mg and Fe on the Ga vaporization was elucidated. Moreover, cation self‐diffusion of139La,84Sr and25Mg as well as cation impurity diffusion of144Nd,89Y and56Fe in polycrystalline samples of doped lanthanum gallate were directly determined for the composition La0.9Sr0.1Ga0.9Mg0.1O2.9as an example, from diffusion profiles determined by SIMS. It was found that diffusion occurs by means of bulk and grain boundaries. The bulk diffusion coefficients are similar for all cations with activation energies which are strongly dependent on temperature. The results are explained by a frozen‐in defect structure at low temperatures in the ABO3perovskite lattice and by proposing a defect cluster containing cation vacancies in the A and B sublattices, as well as oxygen vacancies.
Carbonyl Tailored Electrocatalysts
Authors: Alonso‐Vante N. 
Published: June 2006

AbstractIn recent years, a number of carbonyl clusters have been used as precursors to synthesize electrocatalysts of the nanolength scale for fuel cell reactions. This short review aims to delineate the concepts underlying the synthesis of these type of materials, highlighting the rationale of this type of research. Some selected examples regarding fuel cell reactions at the anode and the cathode are discussed.
Bone marrow and tumour stroma: an intimate relationship
Authors: Direkze Natalie C , Alison Malcolm R 
Published: June 2006

AbstractIn recent years the bone marrow has become recognized as a potential source of cells for non‐haematopoietic wound healing, in some instances demonstrating surprising plasticity in providing new epithelial cells. On the other hand, the contribution of bone marrow derived cells to fibrosis and blood vessel formation is more widely acknowledged. Tumour stroma has a vital role to play in determining cancer growth and spread, and there is a growing realization that the bone marrow has a significant input into this desmoplastic response. This review focuses on the contribution of bone marrow cells to tumour stroma, highlighting the bone marrow as a potential new portal through which to direct anti‐tumour therapies. Copyright © 2006 John Wiley & Sons, Ltd.
Intracranial aneurysm stenting: Follow‐up with MR angiography
Authors: Lövblad Karl‐Olof , Yilmaz Hasan , Chouiter Amine , Ruiz Diego San Millan , Abdo German , Bijlenga Philippe , Tribolet Nicolas de , Ruefenacht Daniel A 
Published: June 2006

AbstractIntracranial stenting is increasingly being used to treat intracranial aneurysms and stenoses. We wanted to assess the utility of magnetic resonance angiography (MRA) in the follow‐up of patients treated with various types of intracranial stents and to assess the utility of performing gadolinium‐enhanced MRA. A total of 19 patients having undergone intracranial stenting for aneurysms were imaged by MRI at 1.5T. A total of 20 stents were placed in 19 patients. In addition to conventional T2‐ and diffusion‐weighted MRI, 3D time‐of‐flight MRA was performed before and after contrast administration. In the case of metallic INX stents (N = 7), there was a signal drop at the level of the vessel. which did not allow to evaluating the parent vessel, whereas this was visible in Nitinol stents (N = 8). Additionally a stent with a wire had a small artifact (N = 3). Contrast administration also improved vessel lumen visualization. In the case of Nitinol stents, MRA can be used to reliably demonstrate the vessel lumen after intracranial stenting. The use of postcontrast 3D time‐of‐flight imaging helps improve the intraluminal definition. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Proton MR spectroscopy of the femoral head—Evaluation of patients at risk for avascular necrosis
Authors: Hou Chun‐han , Shih Tiffany Ting‐Fang , Liu Chieh‐Yu , Li Ying‐Ding , Enright Tony 
Published: June 2006

AbstractPurposeTo detect alteration of the fatty component by measuring the in vivo lipid and water content of normal‐looking femoral heads of patients with and without risk for avascular necrosis (AVN) by using proton MR spectroscopy (MRS).Materials and MethodsMarrow composition was measured by proton MRS (TR/TE = 5000/20 msec) in a sample volume placed in the epiphysis of the intact femoral heads of patients with unilateral osteonecrosis of the hip (group 1, N = 61, then excluding the post‐traumatic or steroid user, final N = 45) and age‐matched controls (group 2, N = 49). Three response variables were derived from MRS: the lipid linewidth (LW), water LW, and lipid/water ratio.ResultsOf the three variables, the lipid and water LWs differed significantly between groups (P < 0.001 and P = 0.05, respectively; t‐test). The lipid/water ratio had borderline significance (P = 0.06). The three variables differed significantly between groups when multivariate regression (P < 0.0001) was analyzed; and age and sex had no significant effect on the three dependent variables.ConclusionProton MRS can depict alteration in the lipid and water composition of normal‐looking femoral heads with and without AVN on the contralateral hip. Proton MRS may be a potential tool for investigating of the femoral head component in vivo and predicting the risk for development of AVN. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Analysis Of A 105‐year time series of precipitation observed at Uccle, Belgium
Authors: De Jongh Inge L. M. , Verhoest Niko E. C. , De Troch FranÇOis P. 
Published: June 2006

AbstractThe yearly, monthly and seasonal total precipitation of a 105‐year precipitation time series of Uccle, Belgium, were analyzed. Statistically significant trends were found for the yearly total precipitation, for precipitation observed in the winter (DJF) and for the monthly total precipitation of March, using the Mann–Kendall trend test. The few statistically significant trends that were found are shown to be of no statistical significance when the length of the series is changed. Using the adaptive Kolmogorov–Zurbenko (KZA) filter, the droughts around 1920 and during the mid‐1970s and drier‐than‐normal conditions at the beginning of the twentieth century could be detected. Wavelet analysis of the monthly precipitation revealed an expected statistically significant yearly cycle in the data, together with multi‐annual components of 3 and 7 years, which were absent during the period 1935–1945. Copyright © 2006 Royal Meteorological Society
Evaluation of snow/ice albedo parameterizations and their impacts on sea ice simulations
Authors: Liu Jiping , Zhang Zhanhai , Inoue Jun , Horton Radley M. 
Published: June 2006

AbstractClimate models use a variety of snow/ice albedo parameterizations for the ice covered ocean. In this study, we applied in situ measurements (surface temperature, snow depth and ice thickness) obtained from the Surface Heat Budget of the Arctic Ocean (SHEBA) as input values to four different snow/ice albedo parameterizations (representing the spectrum of parameterizations used in stand‐alone sea ice models, numerical weather prediction and regional climate models of the Arctic Basin, and coupled global climate models), and evaluated the parameterized albedos against the SHEBA observed albedo. Results show that these parameterizations give very different representations of surface albedo. The impacts of systematic biases in the input values on the parameterized albedos were also assessed. To further understand how sea ice processes are influenced by differences in the albedo parameterizations, we examined baseline sea ice characteristics and responses of sea ice to an external perturbation for the simulations of the albedo parameterizations using a stand‐alone basin‐scale dynamic/thermodynamic sea ice model. Results show that an albedo treatment of sufficient complexity can produce more realistic basin‐scale ice distributions, and likely more realistic ice responses as climate warms. Copyright © 2006 Royal Meteorological Society
Polymers for tissue engineering, medical devices, and regenerative medicine. Concise general review of recent studies
Authors: Jagur‐Grodzinski Joseph 
Published: June 2006

AbstractRecently investigated applications of polymeric materials for tissue engineering, regenerative medicine, implants, stents, and medical devices are described in the present review. Papers published during the last 2 years about polymeric materials used for preparation of various polymeric scaffolds, methods of fabrication of such scaffolds and their effectiveness in providing support for cell growth and development into various tissues and enhancing or mimicking an extracellular network (ECM's) have been cited. Papers describing the use of such polymeric materials for tissue engineering of cartilage and bones were cited. The exciting developments in the field of regenerative medicine, based on application of the self‐assembled biocompatible polymeric scaffolds for regeneration of tissues and organs are described in some detail. The use of the biocompatible and biodegradable collapsible polymeric stents, as well as the use of biocompatible, but not necessarily biodegradable polymeric materials for protective coatings of metallic stents and reservoirs of drugs, preventing restenosis and other post‐operative complications that may occur after insertion of a stent, have been reviewed. Clinical results pointing out the advantages of such treatments, as well as results indicating their limitations, have been cited. New formulas, for coating implants, stents, and other medical devices, have been discussed. Copyright © 2006 John Wiley & Sons, Ltd.
Synthesis, characterization and liquid crystal‐aligning properties of new poly{3‐[4‐(n‐alkyloxy)phenyloxy]pyromellitimide}s
Authors: Lee Jin Kook , Lee Seong Jun , Jung Jin Chul , Zin Wang‐Cheol , Chang Taihyun , Ree Moonhor 
Published: June 2006

AbstractFour new polypyromellitimides (MCm‐PPIs and MCm‐OPIs, m = 6, 8) that are singly substituted with a flexible n‐alkyloxy side branch at the pyromellitimide ring were prepared by the two‐step polycondensation of 3‐[4‐(n‐alkyloxy)phenyloxy]pyromellitic dianhydrides (MCm‐PMDAs, m = 6, 8) with p‐phenylenediamine (PDA) and 4,4′‐oxydianiline (ODA), respectively. The dianhydride monomers were synthesized from durene via several reaction steps. Inherent viscosities of the precursor poly(amic acid)s ranged from 0.57 to 1.58 dl/g. After chemical structures of the polyimides had been characterized, their thermal properties, crystalline structures, and liquid crystal (LC) aligning abilities on their rubbed thin films were determined and discussed in comparison to the polypyromellitimides that are doubly substituted at the pyromellitimide ring with the same side branches. For all polymers thermogravimetric analysis (TGA) programs showed a typical two‐step degradation behavior with onset temperatures in the 430–455°C range. In X‐ray scattering studies all the samples were found to be amorphous, but the presence of a loosely developed layer structure could be confirmed, in which two main chains gather together to form a double‐strand backbone layer and n‐alkyl branches fill the space between the layers. On the rubbed surfaces of the polyimide thin films LCs uniformly aligned parallel to the rubbing direction with the pre‐tilt angles 5–7° in MCm‐OPIs and 18–32° in MCm‐PPIs. Copyright © 2006 John Wiley & Sons, Ltd.
Statin therapy induces ultrastructural damage in skeletal muscle in patients without myalgia
Authors: Draeger A , Monastyrskaya K , Mohaupt M , Hoppeler H , Savolainen H , Allemann C , Babiychuk EB 
Published: June 2006

AbstractMuscle pain and weakness are frequent complaints in patients receiving 3‐hydroxymethylglutaryl coenzymeA (HMG CoA) reductase inhibitors (statins). Many patients with myalgia have creatine kinase levels that are either normal or only marginally elevated, and no obvious structural defects have been reported in patients with myalgia only. To investigate further the mechanism that mediates statin‐induced skeletal muscle damage, skeletal muscle biopsies from statin‐treated and non‐statin‐treated patients were examined using both electron microscopy and biochemical approaches. The present paper reports clear evidence of skeletal muscle damage in statin‐treated patients, despite their being asymptomatic. Though the degree of overall damage is slight, it has a characteristic pattern that includes breakdown of the T‐tubular system and subsarcolemmal rupture. These characteristic structural abnormalities observed in the statin‐treated patients were reproduced by extraction of cholesterol from skeletal muscle fibres in vitro. These findings support the hypothesis that statin‐induced cholesterol lowering per se contributes to myocyte damage and suggest further that it is the specific lipid/protein organization of the skeletal muscle cell itself that renders it particularly vulnerable. Copyright © 2006 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Calculation of proton affinity using the CR‐CCSD[T]/ECP method
Authors: Morgon Nelson H. 
Published: June 2006

AbstractHigh‐level calculations of proton and electron affinities (PA and EA) of CH2X− and CH2CHCHX− (with X = F, Cl, Br, and I) systems were obtained. The methodology employed in the PA and EA calculations is based on CR‐CCSD[T]/B1//MP2/B0 and CCSD(T)/B1//MP2/B0 levels, respectively. B0 is a (small) valence basis set developed by Stevens and colleagues (SBKJC), and B1 is a larger basis set, with extra diffuse and polarization functions (B0 + s, p, d, and f functions). This scheme has been tested on systems containing H, C, and X atoms, and is shown to give good results. The differences between calculated results of PA and EA and the experimental values are in the range of 0.2–4.5 kJ · mol−1 and 0.01 to 0.10 eV, respectively. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2006
Adapted relativistic prolapse‐free Gaussian basis sets for closed shell atoms up to nobelium and to be used with the uniform sphere nucleus model
Authors: De Macedo Luiz Guilherme M. , Haiduke Roberto L. A. , Comar Moacyr , Da Silva Albérico B. F. 
Published: June 2006

AbstractProlapse‐free relativistic Gaussian basis sets are presented for all the closed‐shell elements up to nobelium, using the spherical nuclear model. These relativistic Gaussian basis sets were generated using the polynomial version of the generator coordinate Dirac–Fock (p‐CGDF) method with the goal of obtaining an energy difference with respect to numerical results in the millihartree order of magnitude, resulting in a good balance between cost and accuracy. The discretization parameters for generating the Gaussian exponents are also presented. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2006
A spatial scan statistic for ordinal data
Authors: Jung Inkyung , Kulldorff Martin , Klassen Ann C. 
Published: June 2006

AbstractSpatial scan statistics are widely used for count data to detect geographical disease clusters of high or low incidence, mortality or prevalence and to evaluate their statistical significance. Some data are ordinal or continuous in nature, however, so that it is necessary to dichotomize the data to use a traditional scan statistic for count data. There is then a loss of information and the choice of cut‐off point is often arbitrary. In this paper, we propose a spatial scan statistic for ordinal data, which allows us to analyse such data incorporating the ordinal structure without making any further assumptions. The test statistic is based on a likelihood ratio test and evaluated using Monte Carlo hypothesis testing. The proposed method is illustrated using prostate cancer grade and stage data from the Maryland Cancer Registry. The statistical power, sensitivity and positive predicted value of the test are examined through a simulation study. Copyright © 2006 John Wiley & Sons, Ltd.
Analysis of the short form‐36 (SF‐36): the beta‐binomial distribution approach
Authors: Arostegui Inmaculada , Núñez‐Antón Vicente , Quintana José M. 
Published: June 2006

AbstractHealth‐related quality of life (HRQoL) is an important indicator of health status and the Short Form‐36 (SF‐36) is a generic instrument to measure it. Multiple linear regression (MLR) is often used to study the relationship of HRQoL with patients' characteristics, though HRQoL outcomes tend to be not normally distributed, skewed and bounded (e.g. between 0 and 100). A sample of 193 patients with eating disorders has been analysed to assess the performance of the MLR under non‐normality conditions. Normal distribution was rejected for seven out of the eight domains. A beta‐binomial distribution is suggested to fit the SF‐36 scores. The beta‐binomial distribution is not rejected for five out of the eight domains. Thus, a beta‐binomial regression (BBR) is suggested to analyse the SF‐36 scores. Results using MLR and BBR have been compared for real and simulated data. Performance of the BBR is shown to be better than MLR in the HRQoL domains with few ordered categories and very similar to MLR in the more continuous domains. Moreover, the interpretation of the estimates obtained with BBR is clinically more meaningful. A common technique of statistical analysis is preferable for all the HRQoL dimensions. Therefore, the BBR approach is recommended not only to detect significant predictors of HRQoL when SF‐36 is used, but also to analyse and interpret the effect of several explanatory variables on HRQoL. Further work is required to test the better performance of BBR against standard methods for other HRQoL outcomes, populations or interventions. Copyright © 2006 John Wiley & Sons, Ltd.
A systematic review of the accuracy of first‐trimester ultrasound examination for detecting major congenital heart disease
Authors: Rasiah S. V. , Publicover M. , Ewer A. K. , Khan K. S. , Kilby M. D. , Zamora J. 
Published: June 2006

AbstractObjectiveTo evaluate the accuracy of first‐trimester ultrasound examination in detecting major congenital heart disease (CHD) using a systematic review of the literature.MethodsGeneral bibliographic and specialist computerized databases along with manual searching of reference lists of primary and review articles were used to search for relevant citations. Studies were included if a first‐trimester ultrasound scan was carried out to detect CHD that was subsequently verified by a reference standard. Data were extracted on study characteristics and quality, and 2 × 2 tables were constructed to calculate sensitivity and specificity.ResultsTen studies (involving 1243 patients) were suitable for inclusion. Of these, four used transabdominal ultrasonography, four used transvaginal and two used a combination. Pooled sensitivity and specificity were 85% (95% CI, 78–90%) and 99% (95% CI, 98–100%), respectively.ConclusionUltrasound examination of the fetus in the first trimester is feasible for accurately detecting major CHD. It may be offered to women at high risk of having children with CHD. Copyright © 2006 ISUOG. Published by John Wiley & Sons, Ltd.
Prenatal diagnosis and outcome for fetuses with congenital absence of the pulmonary valve
Authors: Galindo A. , Gutiérrez‐Larraya F. , Martínez J. M. , del Rio M. , Grañeras A. , Velasco J. M. , Puerto B. , Gratacos E. 
Published: June 2006

AbstractObjectivesTo analyze fetal echocardiographic findings of absent pulmonary valve syndrome (APVS), its association with chromosomal and extracardiac anomalies including nuchal translucency (NT) and the outcome after diagnosis.MethodsData of 14 fetuses with confirmed APVS retrospectively collected in two tertiary referral centers between 1998 and 2004 were analyzed. The variables examined were: reason for referral, gestational age at diagnosis and associated abnormalities, including first trimester NT thickness. Cardiac evaluation included measurement of cardiothoracic ratio, diameter of pulmonary arteries and Doppler flow in the pulmonary trunk. Information was retrieved from clinical files, recorded videotapes and stored images. Karyotyping including examination for the 22q11 deletion was performed in all cases.ResultsMean gestational age at diagnosis was 28 weeks, with 5/14 (36%) diagnosed before 22 weeks. In 13/14 (93%) there was an associated ventricular septal defect (subaortic in 12 fetuses and inlet‐type in one) and all 13 had tetralogy of Fallot. Enlargement of the central pulmonary arteries and cardiomegaly were present in all cases diagnosed after 22 weeks. Of the five fetuses in which APVS was detected before 22 weeks, four (80%) had a normal pulmonary trunk diameter, two (40%) had normal pulmonary branches and three (60%) had normal cardiac size. The arterial duct was absent in 11/14 (79%). A correlation between presence of the arterial duct and the size of the central pulmonary arteries or cardiomegaly could not be established. Increased NT was observed in 4/10 cases (40%) for which this information was available. 22q11 microdeletion was diagnosed in three fetuses (21%). There were five terminations of pregnancy, one intrauterine death, five neonatal deaths and one infant death. Of the six neonates with respiratory distress, only one (17%) survived and of the eight babies in whom there was an intention to treat, two survived (25%).ConclusionsAPVS can be accurately diagnosed by fetal echocardiography but screening ultrasound in the mid‐second trimester is likely to have a low detection rate, probably due to the incomplete expression of the disease at this point. Many fetuses with APVS have an increased NT in the first trimester and this may help an earlier recognition of the defect. The most common associated karyotype anomaly is 22q11 microdeletion. Enlargement of the central pulmonary arteries is mainly related to the gestational age at diagnosis. Our results confirm that the outlook for these patients is extremely poor. Copyright © 2006 ISUOG. Published by John Wiley & Sons, Ltd.