bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analysis of biological prognostic factors using tissue microarrays in neuroblastic tumors
Authors: Piqueras Marta , Navarro Samuel , Castel Victoria , Cañete Adela , Llombart‐Bosch Antonio , Noguera Rosa 
Published: November 2008

AbstractBackgroundNeuroblastic tumors (NT) are pediatric neoplasms with a heterogeneous genetic profile. They present genotypic alterations of prognostic value, the study of which is mandatory in designing therapeutic management. Tissue microarrays (TMA) from paraffin material allow the analysis of a large number of cases with minimal costs. The main purpose of the present study is to analyze specific genetic markers of neuroblastic tumors included in TMAs and determine their prognostic value. We compare the results obtained by different molecular techniques at different substrates to evaluate the feasibility of these assays.ProcedureOne hundred thirty‐nine samples were included in four different TMAs. We performed FISH assays to determine the status of MYCN gene, 1p36 region and 17q23 arm. The prognostic value of the genetic markers as well as the statistical correlation among clinical variables and outcome were analyzed by SPSS.ResultsMYCN amplification was detected in 35.3% of the cases, whereas 1p36 deletion and 17q23 gain was observed in 46.8% and 58.3% of the cases, respectively. An adverse prognosis was noted among these patients. Other adverse factors were age (>18 months) as well as high stage of disease (stage 4). Phenotypic signs of differentiation correlated with good outcome.ConclusionRetrospective studies using paraffin‐embedded tissues assembled in TMA are a useful tool for the analysis of prognostic factors in NT. Pediatr Blood Cancer 2009;52:209–214. © 2008 Wiley‐Liss, Inc.
High‐resolution array genomic hybridization in prenatal diagnosis
Authors: Friedman J. M. 
Published: November 2008

AbstractArray genomic hybridization (AGH) can detect chromosomal gains or losses that are 100 times smaller than those identifiable by conventional cytogenetic methods. Genome‐wide AGH can identify genomic imbalance that causes birth defects and mental retardation at least twice as frequently as conventional cytogenetic analysis. Using AGH as a prenatal test for fetal genomic imbalance offers the promise of detecting pathogenic gain or loss of genomic material more quickly and much more frequently than current methods. However, the chance of finding a result of uncertain clinical significance is much greater than with conventional cytogenetic analysis, and the benefit–cost ratio of doing AGH in addition to conventional cytogenetic analysis in pregnancies at high risk for Down syndrome is likely to be poor. Very little is known about the natural history and range of clinical variability associated with most pathogenic submicroscopic copy number variants (CNVs). It seems doubtful that patients can be adequately counseled for prenatal AGH testing in most cases because the risks and benefits are unknown. At present, AGH should be offered for prenatal diagnosis only if the pregnancy is at especially high risk of having a pathogenic CNV or if AGH is being done as part of a clinical trial. Copyright © 2008 John Wiley & Sons, Ltd.
Pediatric drug surveillance and the food and drug administration's adverse event reporting system: an overview of reports, 2003–2007
Authors: Johann‐Liang Rosemary , Wyeth Jo , Chen Min , Cope Judith U. 
Published: November 2008

AbstractPurposeOur objective was to examine the numbers and characteristics of US pediatric adverse events (AEs) reported to the Food and Drug Administration (FDA)'s adverse event reporting system (AERS) for 5 years following implementation of the Best Pharmaceuticals for Children Act (BPCA) in 2002.MethodsWe analyzed reports in AERS received by FDA from January 1, 2003 to January 1, 2008 for overall numbers, age, gender, and seriousness of outcome in children and adults. Pediatric and adult age groups (<2, 2–10, 11–17, 18–50, and >50 years of age) were further evaluated for most frequently reported suspect drug classes and AEs.ResultsSeventy‐two percent of 815 267 crude count reports had specified age information. Six percent of the total reports with age information reported age <18 years. Numbers of AEs being reported for children have remained steady, while those for adults have increased. The proportion of serious AEs reported was similar for pediatrics as compared to adults. Frequently reported suspect drug classes noted in pediatric age groups that were not observed in adults included anticonvulsants, attention deficit hyperactivity disorder (ADHD), anti‐acne, and respiratory medications.ConclusionsThis overview highlights the need for strengthening the passive drug surveillance system from a pediatric perspective, as well as investing in more active surveillance systems. Drug safety initiatives to better capture risk information in order to balance the risk/benefit of drug use in children. Copyright © 2008 John Wiley & Sons, Ltd.
Synthesis, characterization, and bulk properties of amphiphilic copolymers containing fluorinated methacrylates from sequential copper‐mediated radical polymerization
Authors: Hansen Natanya M. L. , Gerstenberg Michael , Haddleton David M. , Hvilsted Søren 
Published: November 2008

AbstractThe partly fluorinated monomers, 2,2,2‐trifluoroethyl methacrylate (3FM), 2,2,3,3,4,4,5,5‐octafluoropentyl methacrylate (8FM), and 1,1,2,2‐tetrahydroperfluorodecyl methacrylate (17FM) have been used in the preparation of block copolymers with methyl methacrylate (MMA), 2‐methoxyethyl acrylate (MEA), and poly(ethylene glycol) methyl ether methacrylate (PEGMA) by Atom Transfer Radical Polymerization. A kinetic study of the 3FM homopolymerization initiated with ethyl bromoisobutyrate and Cu(I)Br/N‐(n‐propyl)‐2‐pyridylmethanimine reveals a living/controlled polymerization in the range 80–110 °C, with apparent rate constants of 1.6 · 10−4 s−1 to 2.9 · 10−4 s−1. Various 3FM containing block copolymers with MMA are prepared by sequential monomer addition or from a PMMA macroinitiator in all cases with controlled characteristics. Block copolymers of 3FM and PEGMA resulted in block copolymers with PDI < 1.22, whereas block copolymers from 3FM and MEA have less controlled characteristics. The block copolymers based on MMA with 8FM and 17 FM have PDI's < 1.30. The glass transition temperatures of the block copolymers are dominated by the majority monomer, as the sequential monomer addition results in too short pure blocks to induce observable microphase separation. The thermal stability of the fluorinated poly((meth)acrylate)s in inert atmosphere is less than that of corresponding nonfluorinated poly((meth)acrylate)s. The presence of fluorinated blocks significantly increases the advancing water contact angle of thin films compared to films of the nonfluorinated poly((meth)acrylate)s. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 8097–8111, 2008
Preparation of polybenzoxazole fibers via electrospinning and postspun thermal cyclization of polyhydroxyamide
Authors: Hsu Steve Lien‐Chung , Lin Kuen‐Shian , Wang Chi 
Published: November 2008

AbstractPolybenzoxazole (PBO) fibers with a submicron diameter were successfully prepared by electrospinning its precursor, polyhydroxyamide (PHA), solutions to obtain the PHA fibers first, followed by appropriate thermal treatments for cyclization reaction. BisAPAF‐IC PHA with two different molecular weights (MWs) were synthesized from a low temperature polymerization of 2,2′‐bis(3‐amino‐4‐hydroxyphenyl) hexafluoropropane (BisAPAF) and isophthaloyl chloride (IC). Using dimethylacetamide (DMAc) and tetrahydrofuran (THF), solvent effects on the electrospinnability of PHA solutions were investigated. For balancing the solution properties, it was found that DMAc/THF mixture with a weight ratio of 1/9 was the best cosolvent to prepare smooth PHA fibers; uniform PHA fibers with a diameter of 325–720 nm were obtained by using 20 wt % PHA/(DMAc/THF) solutions. For a fixed PHA concentration, solutions with a lower MW of PHA yielded thinner electrospun fibers under the same electrospinning condition. After obtaining the electrospun BisAPAF‐IC PHA fibers, subsequent thermal cyclization up to 350 °C produced the corresponding thermally stable BisAPAF‐IC PBO fibers with a diameter of 305–645 nm. The structure of the precursor fibers and the fully cyclized fibers were characterized by FTIR. For the cyclized BisAPAF‐IC PBO fibers, thermogravimetric analysis showed a 5% weight loss temperature at 523 °C in nitrogen atmosphere. The interconnected fiber structure in the BisAPAF‐IC PBO fiber mats was irrelevant to the curing process, but resulted from the jet merging during the whipping process as revealed by the high speed camera images. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 8159–8169, 2008
Monitoring Batch Cooling Crystallization Using NIR: Development of Calibration Models Using Genetic Algorithm and PLS
Authors: Li Rui F. , Wang Xue Z. , Abebe Solomon B. 
Published: November 2008

AbstractNear infrared spectroscopy (NIR) uses fiber‐optics for rapid data transmission, is robust, simple, and sensitive at both low and high solution concentrations. Therefore, it is particularly suitable for monitoring industrial processes. This study investigates the use of NIR for monitoring batch cooling crystallization processes, and emphasis is placed on applying genetic algorithm (GA) for wavelength selection in partial least squares calibration model development. The calibration data was collected for under‐saturated and saturated solutions, as well as for α‐ and β‐form crystal slurries of L‐glutamic acid at a variety of solution concentrations, temperatures, and solid concentrations and sizes. The GA method proves to be capable of effectively selecting a small number of wavelengths and the models thus developed give improved prediction performance in terms of generalization capability compared to models derived using the full spectrum. The developed models are successfully applied to monitoring batch cooling crystallization of L‐glutamic acid under seeded and unseeded conditions and with varied cooling rates.
Is chest sonography a breakthrough in diagnosis of pulmonary thromboembolism in children?
Authors: Kosiak Mateusz , Korbus‐Kosiak Anna , Kosiak Wojciech , Potaz Piotr 
Published: November 2008

AbstractObjectiveSonographic criteria of pulmonary thromboembolism (PTE) have been already evaluated basing on adult patients. There are limited studies to determine diagnostic value of chest ultrasound (CUS) in pediatric PTE. The aim of our study was to present usefulness of ultrasound examination of chest in diagnosis of PTE in children.Material and MethodsWe present results of chest ultrasound examinations of six children: three teenagers—13‐year‐old boy treated for primary antyphospholipid syndrome, 14‐year‐old boy with Wegeners' granuloma, and 15‐year‐old girl with urosepsis—where sonographic results were compared to CT results, and three newborns with congenital heart disease—two boys treated for hypoplastic left heart syndrome (HLHS) and one for duct‐dependent coarctation of the aorta (CoA, PDA). Because of severe clinical condition of the newborns, other imaging tests could not be performed. Ultrasound examination was performed as bedside emergency examination using GE Logic 500 with linear probe 8.2–11.0 MHz.ResultsIn all cases suggestion of PTE was based on ultrasound examination. Sonograms showed: bilateral, peripheral, subpleural, hypoechoic, triangular and oval lesions, accompanied by pleural effusion. In all three teenagers the diagnosis of PTE was confirmed by CT.ConclusionsBedside chest ultrasound examination is especially useful in children with high risk of PTE and in critical general condition. In newborns in severe general condition ultrasound examination of chest should be first imaging test for PTE. It is significant to set on a multicenter study to evaluate the diagnostic value of chest ultrasound in diagnosis of PTE in children. Pediatr. Pulmonol. 2008; 43:1183–1187. © 2008 Wiley‐Liss, Inc.
Flexible bronchoscopy in pediatric intensive care
Authors: Davidson Mark G. , Coutts Jonathan , Bell Graham 
Published: November 2008

AbstractObjectiveTo define the benefits of a flexible bronchoscopy (FB) service in a Paediatric Intensive Care Unit (PICU).DesignReview of the first 200 FBs undertaken in a large PICU.SettingLarge cardiac and medical PICU in the United Kingdom, also providing extra‐corporeal life support.Patients129 patients (78 males, 51 females, median age 9.9 months, median weight 4.6kg) underwent FB from August 1990 to June 2003.InterventionsBroncho‐alveolar lavage (BAL) as indicated at time of bronchoscopy.MeasurementsBasic patient parameters were identified, including ventilation modes and diagnoses. FB findings were correlated with microbiology results.Main resultsThe majority of the FBs were diagnostic (161 of 200). 114 of these were undertaken to exclude underlying airway abnormalities and 47 to aid the diagnosis of pneumonia. Therapeutic procedures including bronchial stenting, directed surfactant instillation and broncho‐alveolar toileting were undertaken in 39 cases. 68% of the diagnostic FBs were deemed to be abnormal. 16% had significant extra‐luminal airway obstruction. 24% had new findings of airway anomalies. 14.5% of the FBs showed endo‐tracheal tube misplacement. Positive microbiological results which altered or confirmed changes in patient management occurred in 46.1% children who had BAL specimens cultured. 80 of the FBs were undertaken whilst the children were receiving extra‐corporeal life support. Only one FB procedure was ceased because of patient instability.ConclusionThere is a high yield of positive findings from undertaking FB both anatomically and microbiologically. FB should be seen as a routine diagnostic and therapeutic tool in paediatric intensive care. Pediatr. Pulmonol. 2008; 43:1188–1192. © 2008 Wiley‐Liss, Inc.
Nanoscale investigation of light‐trapping in a‐Si:H solar cell structures with randomly textured interfaces
Authors: Bittkau Karsten , Beckers Thomas , Fahr Stephan , Rockstuhl Carsten , Lederer Falk , Carius Reinhard 
Published: November 2008

AbstractLight trapping in thin‐film silicon solar cell arising from randomly textured ZnO front contact layers is investigated in the optical near‐field experimentally and theoretically. The experimental data are obtained from near‐field scanning optical microscopy, theoretical data are calculated using rigorous diffraction theory. The surface of the randomly textured ZnO consists of statistically distributed craters with different shapes. Along the rims of the craters light localizations are found. Photon jets emerge from the vertices of the surface profile. From the theoretical study, the local absorption enhancement is calculated. The results provide important insight into the local effects of light trapping in thin‐film optoelectronic devices and strategies for optimizing the external quantum efficiency in thin‐film silicon solar cells are discussed. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Directional selectivity and ultra‐light‐trapping in solar cells
Authors: Ulbrich Carolin , Fahr Stephan , Üpping Johannes , Peters Marius , Kirchartz Thomas , Rockstuhl Carsten , Wehrspohn Ralf , Gombert Andreas , Lederer Falk , Rau Uwe 
Published: November 2008

AbstractDirectional and energy selective optical surface structures attached to solar cells may result in both, enhancement or deterioration of photovoltaic performance of a solar cell. On the one hand, restricting the cell acceptance to the small incidence angle of direct and circumsolar irradiation enhances the maximum path length of the light in a solar cell with Lambertian surfaces even above the Yablonovitch limit (ultra‐light‐trapping). On the other hand, restrictions to small acceptance angles imply losses of diffuse sunlight, even for perfectly tracked cells. Using temporally resolved solar irradiation spectra, we simulate the enhancement and loss in the annual energy yield of silicon solar cells of various thicknesses. We assume an idealized angular and energy selective filter on top of the Lambertian surface of the absorber and compare the results to a Lambertian surface only. We find a maximum annual gain in the energy density of 32.5% for 1 μm, and of ∼10% for 10 μm and 100 μm thick perfectly tracked crystalline silicon solar cells. The simulation implies various tracking modes and two different locations. Finally, we introduce two possible realizations of such a filter; a Rugate stack and inverted opals. In experimental measurements, we could verify the absorptance enhancement by such a structure applied on top of a thin silicon wafer. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Photonics in photovoltaic systems
Authors: Gombert Andreas , Luque Antonio 
Published: November 2008

AbstractThis paper gives an overview on photonics for photovoltaic systems. Starting from the spectral and angular distribution of the electromagnetic radiation from the sun, many important optical approaches how to improve the efficiency of solar cells are presented and discussed. Topics include antireflective coatings, various light trapping structures, refractive, reflective and fluorescent concentrators, and components for spectral management. The theoretical background is shortly described and examples of the experimental and also of the commercial realisation are given. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Light trapping in organic solar cells
Authors: Niggemann Michael , Riede Moritz , Gombert Andreas , Leo Karl 
Published: November 2008

AbstractOne key problem in optimizing organic solar cells is to maximize the absorption of incident light and to keep the charge carrier transport paths as short as possible in order to minimize recombination losses during the charge carrier extraction. The large versatility of organic semiconductors and compositions requires specific optimization of each system. Due to the small thickness of the functional layers in the order of several ten nanometres, coherent optics has to be considered and therefore interference effects play a dominant role. Here we present and discuss concepts for light trapping in organic solar cells. These are wide gap layers in planar solar cells, folded solar cell architectures benefiting from the illumination under inclined incident angles and multiple reflections and absorptions as well as diffraction gratings embossed into the photoactive layer. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Can we use the CO2concentrations determined by continuous‐flow isotope ratio mass spectrometry from small samples for the Keeling plot approach?
Authors: Joos Ottmar , Saurer Matthias , Heim Alexander , Hagedorn Frank , Schmidt Michael W. I. , Siegwolf Rolf T. W. 
Published: November 2008

AbstractA common method to estimate the carbon isotopic composition of soil‐respired air is to use Keeling plots (δ13C versus 1/CO2concentration). This approach requires the precise determination of both CO2concentration ([CO2]), usually measured with an infrared gas analyser (IRGA) in the field, and the analysis ofδ13C by isotope ratio mass spectrometry (IRMS) in the laboratory. We measured [CO2] with an IRGA in the field (n = 637) and simultaneously collected air samples in 12 mL vials for analysis of the13C values and the [CO2] using a continuous‐flow isotope ratio mass spectrometer. In this study we tested if measurements by the IRGA and IRMS yielded the same results for [CO2], and also investigated the effects of different sample vial preparation methods on the [CO2] measurement and the thereby obtained Keeling plot results. Our results show that IRMS measurements of the [CO2] (during the isotope analysis) were lower than when the [CO2] was measured in the field with the IRGA. This is especially evident when the sample vials were not treated in the same way as the standard vials. From the three different vial preparation methods, the one using N2‐filled and overpressurised vials resulted in the best agreement between the IRGA and IRMS [CO2] values. There was no effect on the13C‐values from the different methods. The Keeling plot results confirmed that the overpressurised vials performed best. We conclude that in the cases where the ranges of [CO2] are large (>300 ppm; in our case it ranged between 70 and 1500 ppm) reliable estimation of the [CO2] with small samples using IRMS is possible for Keeling plot application. We also suggest some guidelines for sample handling in order to achieve proper results. Copyright © 2008 John Wiley & Sons, Ltd.
Dynamic perspectives on social characteristics and sustainability in online community networks
Authors: Otto Peter , Simon Martin 
Published: November 2008

AbstractOnline community networks can help organizations improve collaboration. However, in spite of their potential value, there has been little empirical research into two important network factors that determine their success: social characteristics of users and changes in operations that result from network evolution. Our research addresses these deficiencies by using a cultural framework. Derived from anthropology, it extends previous system dynamics research on online community networks. The framework acts as a lens, enabling a better understanding of the effects that changes in these factors bring to online community networks. Using data collected from Wikipedia for model calibration, our findings suggest that, contrary to conventional wisdom, removing policies that focus on building group commitment does not lower performance. The results also show that online networks need structural control, otherwise their attractiveness, credibility and, subsequently, content value might all decrease. To ensure sustainability the network must be monitored, especially during the early stages of its evolution, so that rules and regulations that ensure value and validity can be selectively employed. Copyright © 2008 John Wiley & Sons, Ltd.
Composite beam composed of steel and precast concrete (Modularized Hybrid System, MHS). Part I: experimental investigation
Authors: Hong Won‐Kee , Park Seon‐Chee , Kim Jin‐Min , Lee Seung‐Geun , Kim Seung‐Il , Yoon Ki‐Joon , Lee Ho‐Chan 
Published: November 2008

AbstractAn experimental investigation of composite beams composed of wide flange steel and precast concrete is presented. The bottom flange of the steel section is encased in precast concrete. Utilizing the merits of both steel and concrete material, the size of the steel beams can be reduced without sacrificing performance. The bottom flange of the steel beam is reinforced with concrete at a manufacturing plant, eliminating the use of temporary pour forms. The composite beams were tested to investigate how the size of the wide flange steel and how the top and bottom reinforcements influence the behaviour of the beams. Flexural load carrying capacity, load displacement relationships and failure modes were examined. The test specimens were T‐shaped composite beams with slabs, each measuring 10‐m long. The flexural moment strength of all of the composite beams—at both the yield limit state and the maximum load limit state—was measured and compared with the analytical flexural capacity.The stiffness degradation, ductility and dissipating energy capabilities of the composite beams were investigated based on the hysteresis curves. The composite beams tested in this study successfully reduced both the floor height of the building and the size of the steel beams needed to meet code requirements. Copyright © 2008 John Wiley & Sons, Ltd.