bluuebunny/crossref_metadata_2025_split huggingface dataset:
Estimation of the optimal shift for the discrete Helmholtz operator preconditioned with a shifted Laplacian
Authors: Gijzen M.B. van , Erlangga Y.A. , Vuik C. 
Published: September 2008

AbstractShifted Laplace preconditioners have attracted considerable attention as a technique to speed up convergence of iterative solution methods for the Helmholtz equation. In this paper we present an approach to determine a near‐optimal value for the shift. We illustrate our results with a geophysical test problem. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On the inertial subrange of symmetry‐preserving regularization models for turbulent flow
Authors: Verstappen Roel 
Published: September 2008

AbstractFoias et al. [1] have proven the existence of the inertial subrange for the (incompressible) Navier‐Stokes equations. In this paper, we proof the same result for any skew‐symmetric regularization of the nonlinearity in the Navier‐Stokes equations. A simple dimensional analysis gives then Kolmogorov's ‐5/3 spectrum. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A proof of MIKOTA's conjecture
Authors: Weber Wolfgang , Anders Bernd 
Published: September 2008

AbstractComing from MIKOTA's conjecture [1] a proof is given by examinating the properties of the occuring matrices M, K and M–1K and deducing the natural frequencies of the chain structured mass‐spring vibration system. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Analyzing securitization processes using simulation methods
Authors: Radoslaw Pytlak , Marcin Wierzbicki 
Published: September 2008

AbstractThe aim of this paper is to present an analysis of securitization processes using simulation and optimization methods. We discuss the main risk factors that may affect profitability of the process. These risk factors are interest rates and mortgage prepayments. We combine latest risk factor models to create a consistent framework to analyze and improve securitization processes. We then show that making ad hoc securitization decisions may be far less efficient than by solving optimization problems. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Collective coordinates and the mechanism for conformational transitions of complex molecules
Authors: Yanao Tomohiro , Koon Wang S. , Marsden Jerrold E. , Kevrekidis Ioannis G. 
Published: September 2008

AbstractReduction of dimensionality is crucial for the deeper understanding of the mechanism for large‐amplitude conformational transitions of complex molecules. By taking up a six‐atomcluster as an illustrative example, we present a general methodology to understand conformational transitions of molecules in terms of the low‐dimensional dynamics of molecular gyration radii. The dynamics of gyration radii is generally governed by the interplay between the ordinary potential force and a dynamical force called the internal centrifugal force. We show that the internal centrifugal force can be more important than the original potential barrier and gives rise to a new dynamical barrier that truly dominates the conformational transitions of the system. This kind of dynamical effect should be crucially important in a wide class of molecular reaction dynamics. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Neonatal Apnea: What's New?
Authors: Abu‐Shaweesh Jalal M. , Martin Richard J. 
Published: September 2008

AbstractApnea of prematurity (AOP) remains a major clinical problem in present day neonatology that warrants frequent evaluations and imposes challenges in therapeutic strategies. Although the pathogenesis of AOP is poorly understood, it is probably a manifestation of physiologic immaturity of breathing control rather than a pathologic disorder. Immature breathing responses to hypoxia, hypercapnia and exaggerated inhibitory pulmonary reflexes in preterm infants might also contribute to the occurrence or severity of AOP. Recent data suggest a role for genetic predisposition. Although typically resolve with maturation, the role of bradycardia and desaturation episodes associated with AOP in the development of sleep disorder breathing and neurodevelopmental delay needs further clarification. Pharmacological treatment with methylxanthines and CPAP remain the mainstay for treatment of AOP. However, recent studies have implicated central inhibitory neuromodulators including prostaglandins, GABA and adenosine in its pathogenesis, the fact that might provide future specific targets for treatment. This review will summarize new insights involving these issues as well as others involving the pathogenesis, treatment strategies and consequences of apnea in premature infants. Pediatr Pulmonol. 2008; 43:937–944. © 2008 Wiley‐Liss, Inc.
Safety of bronchoalveolar lavage in young children with cystic fibrosis
Authors: Wainwright Claire E. , Grimwood Keith , Carlin John B. , Vidmar Suzanna , Cooper Peter J. , Francis Paul W. , Byrnes Catherine A. , Whitehead Bruce F. , Martin A. James , Robertson Ian F. , Cooper David M. , Dakin Carolyn J. , Masters Ian. B. , Massie R. John , Robinson Philip J. , Ranganathan Sarath , Armstrong David S. , Patterson Lyndall K. , Robertson Colin F. 
Published: September 2008

AbstractObjective:Our aim was to determine the safety of BAL in young children <6 years with CF.Methods:As part of a multi‐center study of BAL‐directed therapy, children with CF < 6 years had one or more BALs between September 1999 and December 2005. Adverse events were recorded intraoperatively and for 24 hr thereafter. Clinical characteristics before BAL, findings at bronchoscopy and BAL results were assessed as risk factors for adverse events.Results:333 BALs were conducted in 107 (56 males) children, median age 23.5 (range 1.6–67.5) months, including 170 (51%) for pulmonary exacerbation. 29 BALs (8.7%) were followed by fever ≥38.5°C and 10 (3%) had clinically significant episodes (five intraoperative hemoglobin desaturations to <90% requiring intervention, one tachyarrhythmia, two needing post‐operative supplemental oxygen, one hospitalization for stridor). Two contaminated bronchoscopes were detected. 180 minor adverse events were recorded in 174 (52%) BAL procedures (137 altered cough, 41 fever <38.5°C). Low percentage BAL return (P = 0.002) and focal bronchitis (P = 0.02) were associated with clinically significant deterioration. Multivariable analysis identified Streptococcus pneumoniae (OR 22.3; 95% confidence interval (CI); 6.9,72), Pseudomonas aeruginosa (OR 2.4; 95% CI 1.0, 5.8), respiratory signs (OR 5.0; 95% CI 1.7, 14.6) and focal bronchitis (OR 5.9; 95% CI 1.2, 29.8) as independent risk factors for post‐bronchoscopy fever ≥38.5°C.Conclusions:Adverse events are common with BAL in young CF children, but are usually transient and well tolerated. Parents should be counseled that signs of a pre‐existing lower respiratory infection are associated with increased risk of post‐BAL fever. Pediatr Pulmonol. 2008; 43:965–972. © 2008 Wiley‐Liss, Inc.
The SRD5A2 V89L polymorphism is associated with severity of disease in men with early onset prostate cancer
Authors: Scariano John K. , Treat Eric , Alba Frances , Nelson Harold , Ness Scott A. , Smith Anthony Y. 
Published: September 2008

AbstractBACKGROUNDEmerging evidence indicates that testosterone (T), and not dihydrotestosterone (DHT), is the most relevant androgen that promotes carcinogenesis in the prostate. Steroid 5‐alpha reductase type II (SRD5A2) catalyzes the irreversible conversion of T to DHT in male reproductive organs. Because the SRD5A2 gene is highly polymorphic at codon 89, two SRD5A2 isoforms are expressed that differ in Km and Vmax values. The more common and rapid catalytic isoform contains a valine residue at position 89; the slower‐catalytic variant contains leucine at this position.METHODSThirty‐three men with early onset prostate cancer (PCa) were genotyped for the SRD5A2 V89L substitution and other polymorphisms in genes encoding receptors or enzymes that play important roles in pathways of steroid metabolism to ascertain if they were associated with standard clinical measures of disease progression at the time of diagnosis.RESULTSThe expression of at least one SRD5A2 leucine allele in young men with PCa was associated with more significant disease at the time of presentation, as was defined by pretreatment PSA level, clinical staging and Gleason score when compared with affected subjects harboring the more common SRD5A2 valine variant. A dosage effect of a single leucine allele was evident in heterozygotes, as values of their clinical and pathological variables were consistently situated between the extremes of the homozygous V or L phenotypes.CONCLUSIONThe SRD5A2 leucine isoform appears to be acting in a dose‐dependent manner as a significant disease‐modifying factor in young men diagnosed with PCa. Prostate © 2008 Wiley‐Liss, Inc.
Prolonged androgen receptor loading onto chromatin and the efficient recruitment of p160 coactivators contribute to androgen‐independent growth of prostate cancer cells
Authors: Shi Xu‐Bao , Xue Lingru , Zou June X. , Gandour‐Edwards Regina , Chen Hongwu , deVere White Ralph W. 
Published: September 2008

AbstractBACKGROUNDGrowth of most ablation‐resistant prostate cancers (CaPs) is dependent on androgen receptor (AR) activity in chromatin, but cancer cells in these tumors have acquired altered AR activation. It is unclear how the aberrantly activated AR loads onto regulatory regions of AR‐targeted genes. The purpose of this study was to assess the AR chromatin loading in an androgen‐depleted environment.METHODSThe expression of PSA in androgen‐resistant CaP cells was determined using RT‐PCR and Western blot analysis. In order to investigate the binding of the AR to the PSA gene regulatory regions, chromatin immunoprecipitation (ChIP) was performed in the androgen‐independent cds2 cell line in the presence or absence of androgens. In addition, we examined the involvement of p160 coactivators in the chromatin loading of the AR.RESULTSIt was found that constitutive activation of PSA expression was the result of sustained occupancy by the AR at the regulatory region of this gene. This stable AR loading was not blocked by the AR antagonist bicalutamide. Furthermore, androgen‐resistant CaP cells highly expressed both AR and the p160 coactivators and the AR was able to recruit TIF2. Downregulation of TIF2 using short hairpin RNA disrupted the AR loading to the PSA enhancer and subsequently inhibited AR activity.CONCLUSIONProlonged AR localization to the regulatory regions of AR targeted genes and the recruitment of p160 coactivators are a potential mechanism leading to androgen‐independent activation of the AR. Disruption of AR chromatin loading could therefore become an important therapeutic target for this disease. Prostate © 2008 Wiley‐Liss, Inc.
Computerized whole slide quantification shows increased microvascular density in pT2 prostate cancer as compared to normal prostate tissue
Authors: van Niekerk Cornelis G. , van der Laak Jeroen A.W.M. , Börger M. Elisa , Huisman Henk‐Jan , Witjes J. Alfred , Barentsz Jelle O. , Hulsbergen‐van de Kaa Christina A. 
Published: September 2008

AbstractBACKGROUNDContrast enhanced imaging enables powerful, non‐invasive diagnostics, important for detection and staging of early prostate cancer. The uptake of contrast agent is increased in prostate cancer as compared to normal prostate tissue. To reveal the underlying physiological mechanisms, quantification of tissue components in pathology specimens may yield important information. Aim of this study was to investigate whether microvascularity is increased in prostate confined cancer (pT2).METHODSRadical prostatectomy specimens of 26 patients were selected for organ confined peripheral zone tumors which were restricted to one side of the prostate. Microvessels were visualized by immunohistochemistry against CD31. Specimens were scanned using a computer controlled microscope and scanning stage and vessels were recognized automatically. Pseudocolor mappings were produced showing number of vascular profiles (MVD), vascular area (MVA) and perimeter (MVP) in an overview of the entire prostate transection. MVD is a common measure for vascularity, whereas MVA represents the 3D vascular volume and MVP the perfused surface area. Mean, coefficient of variation and 75th percentile of these parameters were calculated automatically in manually indicated areas, consisting of the entire tumor area and the corresponding normal area in the contra lateral side of the prostate.RESULTSThe mappings clearly indicate areas of increased vascularity in prostate transections. In tumor tissue an increase was found compared to normal tissue of 81%, 49%, and 62% for mean MVD, mean MVA and mean MVP, respectively (P < 0.001 for all comparisons). In contrast, the heterogeneity in tumor vasculature was significantly decreased as compared to normal prostate (P < 0.001).CONCLUSIONSCharacteristics of microvasculature deviated significantly in pT2 prostate tumor as compared to normal tissue. Prostate 69: 62–69, 2009. © 2008 Wiley–Liss, Inc.
InGaAsP/InGaAs tandem cells for a solar cell configuration with more than three junctions
Authors: Szabó N. , Sağol B. E. , Seidel U. , Schwarzburg K. , Hannappel T. 
Published: September 2008

AbstractCurrently, triple‐junction solar cells realized from III–V semiconductor compounds hold the solar energy conversion efficiency world record. To improve the efficiency significantly, it is necessary to increase the number of junctions and to involve a sub‐cell with an absorber layer in the band gap range of 1 eV. For the realization of a stacked four‐junction device with optimised band gaps, we have grown InGaAsP/InGaAs tandem cells lattice matched to InP substrates, and investigated properties of the absorber bulk material. Time‐resolved photoluminescence of the low band gap In0.53Ga0.47As absorber embedded between InP barriers was measured. The InGaAs/GaAsSb tunnel diode structure used in the tandem has been processed into a separate device andI–Vcurves were measured. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Monolithically integrated organic waveguide photodiode
Authors: Lamprecht B. , Ditlbacher H. , Jakopic G. , Krenn J. R. 
Published: September 2008

AbstractWe demonstrate the monolithic integration of a microstructured organic photodiode with a planar optical stripe waveguide. The manufacturing of this waveguide‐integrated organic photodiode is based on an UV photolithography process. The integration of photodiodes with optical waveguides represents an essential building block in the field of optoelectronic‐photonic integrated circuits.magnified image(© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electronic structure of GaN(0001)‐2 × 2 thin films grown by PAMBE
Authors: Gutt R. , Lorenz P. , Tonisch K. , Himmerlich M. , Schaefer J. A. , Krischok S. 
Published: September 2008

AbstractGallium nitride thin films were grown on silicon carbide (0001) by plasma‐assisted molecular beam epitaxy (PAMBE). The samples were cooled down in nitrogen plasma and characterized in situ by reflection high energy electron diffraction (RHEED), photoelectron spectroscopy (XPS/UPS), and atomic force microscopy (AFM) revealing stoichiometric and smooth GaN films virtually free of contaminations. We present valence band data obtained by UPS with strong emission from surface states inside the fundamental band gap. These states and the observed 2 × 2 surface reconstruction are highly sensitive towards residual molecules. Once these surface states have disappeared the original state could not be recovered by surface preparation methods underlining the necessity of in situ investigations on as‐grown surfaces. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
‘Big‐eyed frog’ sign on spatiotemporal image correlation (STIC) in the antenatal diagnosis of transposition of the great arteries
Authors: Shih J. C. , Shyu M. K. , Su Y. N. , Chiang Y. C. , Lin C. H. , Lee C. N. 
Published: September 2008

AbstractObjectiveTo determine the value of simultaneous visualization of the cross‐sectional view of both atrioventricular (AV) valves, the pulmonary artery and the aorta (en‐face view of the AV valves and great vessels) in the identification of fetuses with transposition of the great arteries (TGA).MethodsThis was a retrospective analysis of volume datasets obtained with the spatiotemporal image correlation (STIC) technique from 56 fetuses with and 30 fetuses without congenital heart defects. Volume datasets were reviewed offline to compare the en‐face view of the AV valves and great vessels between fetuses with normal echocardiography and those with TGA.ResultsThe en‐face view of both AV valves and great vessels in fetuses with TGA displayed the main pulmonary artery situated side‐by‐side with the aorta (‘big‐eyed frog’ sign). In contrast, fetuses with normal hearts did not have this characteristic sonographic sign. This novel sonographic sign also helped to identify additional cases of TGA in 17 fetuses with complex heart defects.ConclusionThe big‐eyed frog sign may prove helpful in the prenatal diagnosis of TGA. Copyright © 2008 ISUOG. Published by John Wiley & Sons, Ltd.
Efficient convolution with the Newton potential in d dimensions
Authors: Hackbusch W. 
Published: September 2008

AbstractThe paper is concerned with the evaluation of the convolution integral $${\int_{\mathbb{R}^d}\frac{1}{\left\Vert x-y\right\Vert} f(y){\rm d}y}$$ in d dimensions (usually d = 3), when f is given as piecewise polynomial of possibly large degree, i.e., f may be considered as an hp-finite element function. The underlying grid is locally refined using various levels of dyadically organised grids. The result of the convolution is approximated in the same kind of mesh. If f is given in tensor product form, the d-dimensional convolution can be reduced to one-dimensional convolutions. Although the details are given for the kernel $${{1 / \left \Vert x \right\Vert,}}$$ the basis techniques can be generalised to homogeneous kernels, e.g., the fundamental solution $${{const\cdot\left\Vert x\right\Vert ^{2-d}}}$$ of the d-dimensional Poisson equation.
Difference in seasonal activity pattern between non‐native and native ants in subtropical forest of Okinawa Island, Japan
Authors: Suwabe Mayuko , Ohnishi Hitoshi , Kikuchi Tomonori , Kawara Kengo , Tsuji Kazuki 
Published: September 2008

AbstractBiological invasions by non‐native tramp ants are reported throughout the world, particularly in island ecosystems. In Okinawa Island, a subtropical island in south‐western Japan, many tramp ants including the invasive ant, Anoplolepis gracilipes, already occur. In this study activity patterns of the ground‐foraging tramp and native ants were investigated for one year by using food bait traps at the forest edges where both categories of ants coexist. On a seasonal time scale, activity patterns were different between exotic and native ants. Native ants are active and seemingly more dominant from spring to summer whereas tramp ants become more dominant from autumn to winter. These results suggest there might be temporal niche partitioning between tramp and native ants, and native ants might be able to dominate tramp ants in their suitable seasons.
Comparison of In vitro Nanoparticles Uptake in Various Cell Lines and In vivo Pulmonary Cellular Transport in Intratracheally Dosed Rat Model
Authors: Lai Yurong , Chiang Po-Chang , Blom Jason D , Li Na , Shevlin Kimberly , Brayman Timothy G , Hu Yiding , Selbo Jon G , Hu LiangbiaoGeorge 
Published: September 2008

AbstractIn present study, the potential drug delivery of nanoformulations was validated via the comparison of cellular uptake of nanoparticles in various cell lines and in vivo pulmonary cellular uptake in intratracheally (IT) dosed rat model. Nanoparticles were prepared by a bench scale wet milling device and incubated with a series of cell lines, including Caco-2, RAW, MDCK and MDCK transfected MDR1 cells. IT dosed rats were examined for the pulmonary cellular uptake of nanoparticles. The processes of nanoparticle preparation did not alter the crystalline state of the material. The uptake of nanoparticles was observed most extensively in RAW cells and the least in Caco-2 cells. Efflux transporter P-gp did not prevent cell from nanoparticles uptake. The cellular uptake of nanoparticles was also confirmed in bronchoalveolar lavage (BAL) fluid cells and in bronchiolar epithelial cells, type II alveolar epithelial cells in the intratracheally administrated rats. The nanoparticles uptake in MDCK, RAW cells and in vivo lung epithelial cells indicated the potential applications of nanoformulation for poorly soluble compounds. The observed limited direct uptake of nanoparticles in Caco-2 cells suggests that the improvement in oral bioavailability by particle size reduction is via increased dissolution rate rather than direct uptake.
Synthesis, Electrical Measurement, and Field Emission Properties of α-Fe2O3Nanowires
Authors: Hsu Li-Chieh , Li Yuan-Yao , Hsiao Chun-Yen 
Published: September 2008

Abstract
α-Fe2O3nanowires (NWs) were formed by the thermal oxidation of an iron film in air at 350 °C for 10 h. The rhombohedral structure of the α-Fe2O3NWs was grown vertically on the substrate with diameters of 8–25 nm and lengths of several hundred nm. It was found that the population density of the NWs per unit area (D
NWs) can be varied by the film thickness. The thicker the iron film, the more NWs were grown. The growth mechanism of the NWs is suggested to be a combination effect of the thermal oxidation rate, defects on the film, and selective directional growth. The electrical resistivity of a single NW with a length of 800 nm and a diameter of 15 nm was measured to be 4.42 × 103 Ωcm using conductive atomic force microscopy. The field emission characteristics of the NWs were studied using a two-parallel-plate system. A low turn–on field of 3.3 V/μm and a large current density of 10−3 A/cm2(under an applied field of about 7 V/μm) can be obtained using optimal factors ofD
NWsin the cathode.
Fabrication of Large Area Periodic Nanostructures Using Nanosphere Photolithography
Authors: Wu Wei , Dey Dibyendu , Memis Omer G , Katsnelson Alex , Mohseni Hooman 
Published: September 2008

Abstract
Large area periodic nanostructures exhibit unique optical and electronic properties and have found many applications, such as photonic band-gap materials, high dense data storage, and photonic devices. We have developed a maskless photolithography method—Nanosphere Photolithography (NSP)—to produce a large area of uniform nanopatterns in the photoresist utilizing the silica micro-spheres to focus UV light. Here, we will extend the idea to fabricate metallic nanostructures using the NSP method. We produced large areas of periodic uniform nanohole array perforated in different metallic films, such as gold and aluminum. The diameters of these nanoholes are much smaller than the wavelength of UV light used and they are very uniformly distributed. The method introduced here inherently has both the advantages of photolithography and self-assembled methods. Besides, it also generates very uniform repetitive nanopatterns because the focused beam waist is almost unchanged with different sphere sizes.
Nanoporous Silicified Phospholipids and Application to Controlled Glycolic Acid Release
Authors: Kang SangHwa , Lee HyeSun , Lee Jiho , Jeong Seongmin , Choi Jinsub , Lee SangCheon , Kim KyungJa , Chang JeongHo 
Published: September 2008

Abstract
This work demonstrates the synthesis and characterization of novel nanoporous silicified phospholipid bilayers assembled inorganic powders. The materials are obtained by silicification process with silica precursor at the hydrophilic region of phospholipid bilayers. This process involves the co-assembly of a chemically active phospholipids bilayer within the ordered porosity of a silica matrix and holds promise as a novel application for controlled drug release or drug containers with a high level of specificity and throughput. The controlled release application of the synthesized materials was achieved to glycolic acid, and obtained a zero-order release pattern due to the nanoporosity.