bluuebunny/crossref_metadata_2025_split huggingface dataset:
The research of degradability of a novel biodegradable coralline hydroxyapatite after implanted into rabbit
Authors: Ning Yuan , Wei Tian , Defu Chen , Yonggang Xing , Da He , Dafu Chen , Lei Sun , Zhizhong Gao 
Published: March 2008

AbstractTo examine the biodegradability and bone healing effect of a novel biodegradable coralline hydroxyapatite after implanting into the proximal tibia of rabbit. Seventy New Zealand white rabbits were enrolled, bone defects about 10 × 5 × 3 mm3 of bilateral proximal tibias were prepared by drilling, then coralline hydroxyapatite and iliac crest bone were grafted into bilateral bone defects, respectively. Each time five rabbits were sacrificed at 1, 2, 3, 4, 6, 8, 10, 12, 20, 24, 32, 36, 40, and 60 weeks after surgery. Then a series of examination were carried out, including eye view, roentgenographically, and nondecalcification histological examination. Eye view and roentgenographical examination indicate that all the defects grafted with coralline hydroxyapatite exhibited bone fusion, similar to the iliac crest autograft. The bone density of the graft site decreases with time on the X‐ray film. Nondecalcification histological examination results are as followed: In the early time on the sections, the coralline hydroxyapatite looks like interlinked trabecula. Few lymphocytes infiltrate around the trabecula. With time extending, coralline hydroxyapatite looks like thin line or thin circle remnant. The degradation sites are filled with renascence bone. Medulla cavity can be seen in the degradation sites. After grafted in body, coralline hydroxyapatite exhibits little local and general abnormal reaction. It conducts good bone fusion of fracture. Coralline hydroxyapatite can be degraded after grafted into body, which is good for remodeling of bone healing. Hence coralline hydroxyapatite is an ideal bone graft substitute of autograft. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
Synthesis of amphiphilic poly(tetraethylene glycol succinate) and the thermosensitivity of its aggregation in water
Authors: Chen Shusen , Wang Yinong , Fan Yunge , Ma Jianbiao 
Published: March 2008

AbstractAmphiphilic biodegradable polyester, poly(tetraethylene glycol succinate) (PTEGSuc), was synthesized via melt polycondensation of tetraethylene glycol and succinic acid on catalysis of p‐toluenesulfonic acid. It was observed that PTEGSuc could self‐assemble into micelles in water. In addition, thermosensitivity of PTEGSuc aggregation in water was first found in the experiment, and the critical aggregation temperatures could be controlled by solution concentration. Transmission electron microscopy was used to investigate the micellar morphologies of PTEGSuc in different solvents. It was found that particle shape is almost round although the micellar morphology is different depending on the solvent used. Based on the perfect properties, especially in micelle formation and thermosensitivity, PTEGSuc is promising in biomedical field as carrier of drug delivery system, scaffold of tissue engineering, and other medical devices. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
Surface modification of collagen‐based artificial cornea for reduced endothelialization
Authors: Rafat Mehrdad , Matsuura Takeshi , Li Fengfu , Griffith May 
Published: March 2008

AbstractOur objective was to develop collagen‐based hydrogels as tissue substitutes for corneal transplantation. The design of the full‐thickness corneal grafts includes prevention of cell migration onto the posterior surface of the implants, using a plasma‐assisted surface modification technique. Briefly, the hydrogel materials were subjected to ammonia plasma functionalization followed by grafting of alginate macromolecules to the target surface. The treated materials surfaces showed observable decreases in endothelial cell attachment. The decrease in cell attachment and adhesion was dependant upon the concentration of alginate and plasma radio frequency (RF) power. High concentrations of alginate 5% (w/v) and high RF power of 100 W produced surfaces with minimal cell attachment. The plasma‐alginate treatment did not adversely affect the optical or swelling properties of the constructs. Contact angle measurement analysis revealed that the posterior surface hydrophilicity significantly increased after the treatment. The grafting of alginate to the implants surfaces was confirmed by fourier transform infrared spectroscopy. Both of the untreated and alginate grafted corneal materials were found to be superior to human cornea in optical and swelling properties. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
Mesenchymal stem cell‐seeded collagen matrices for bone repair: Effects of cyclic tensile strain, cell density, and media conditions on matrix contraction in vitro
Authors: Sumanasinghe Ruwan D. , Osborne Jason A. , Loboa Elizabeth G. 
Published: March 2008

AbstractType I collagen is the most abundant extracellular matrix protein in bone and contains arginine– glycine–aspartic acid sequences that promote cell adhesion and proliferation. We have previously shown that human mesenchymal stem cells (hMSCs) seeded in three‐dimensional (3D) collagen gels upregulate BMP‐2 mRNA expression in response to tensile strain, indicative of osteogenesis. Therefore, collagen could be a promising scaffold material for functional bone tissue engineering using hMSCs. However, high contraction of the collagen gels by hMSCs poses a challenge to creating large, tissue‐engineered bone constructs. The effects of cyclic tensile strain, medium (with and without dexamethasone), and hMSC seeding density on contraction of collagen matrices have not been investigated. hMSCs were seeded in 3D collagen gels and subjected to cyclic tensile strain of 10% or 12% for 4 h/day at a frequency of 1 Hz in osteogenic‐differentiating or complete MSC growth media for up to 14 days. Viability of hMSCs was not affected by strain or media conditions. While initial seeding density affected matrix contraction alone, there was a high interdependence of strain and medium on matrix contraction. These findings suggest a correlation between hMSC proliferation and osteogenic differentiation on collagen matrix contraction that is affected by media, cell‐seeding density, and cyclic tensile strain. It is vital to understand the effects of culture conditions on collagen matrix contraction by hMSCs in order to consider hMSC‐seeded collagen constructs for functional bone tissue engineering in vitro. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
PMMA particle‐mediated DNA vaccine for cervical cancer
Authors: Lou Pei‐Jen , Cheng Wen‐Fang , Chung Yi‐Chen , Cheng Che‐Yuan , Chiu Lien‐Hua , Young Tai‐Horng 
Published: March 2008

AbstractDNA vaccination is a novel immunization strategy that possesses many potential advantages over other vaccine strategies. One of the major difficulties hindering the clinical application of DNA vaccination is the relative poor immunogenicity of DNA vaccines. Poly(methyl methacrylate) (PMMA) is a synthetic polymer approved by the Food and Drug Administration for certain human clinical applications such as the bone cement. In vivo, PMMA particles are phagocytosable and have the potential to initiate strong immune responses by stimulating the production of inflammatory cytokines. In this study, we synthesized a series of PMMA particles (PMMA 1–5) with different particle sizes and surface charges to test the feasibility of implementing such polymer particles for DNA vaccination. To our knowledge, this is the first report to show that the gene gun can deliver DNA vaccine by propelling PMMA particles mixed with plasmid DNA for cervical cancer. It was found that PMMA 4 particles (particle size: 460 ± 160 nm, surface charge: +11.5 ± 1.8 mV) stimulated the highest level of TNF‐α production by macrophages in vitro and yielded the best result of antitumor protection in vivo. Therefore, our results possess the potential for translation and implementation of polymer particles in gene gun delivering DNA vaccination. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
Suicidal risk in young adult offspring of mothers with bipolar or major depressive disorder: a longitudinal family risk study
Authors: Klimes‐Dougan Bonnie , Lee Chih‐Yuan S. , Ronsaville Donna , Martinez Pedro 
Published: March 2008

AbstractRecent evidence has highlighted suicidal risk associated with bipolar disorder (BD). Using a family risk approach, the goal of this study was to evaluate suicidal thoughts and behaviors longitudinally from childhood to young adulthood in children of mothers with BD, Major depressive disorder (MDD), and well mothers. Few group differences were found for cross‐sectional assessments of suicidal thoughts and behavior in young adulthood; the offspring of MDD demonstrate an earlier onset and more persistent suicidality than other groups, but by young adulthood, BD offspring appear to be comparable to MDD offspring in their rates of suicidality. The longitudinal assessments reveal a pattern of higher suicidal risk in MDD offspring, more intermediate risk in BD offspring, and lower risk in well offspring. Precursors and correlates of suicidal thoughts and behaviors were also examined. These findings suggest diverse developmental trajectories based on family risk and have implications for planning preventive intervention. © 2008 Wiley Periodicals, Inc. J Clin Psychol 64: 531–540, 2008.
New bounds for the chromatic number of graphs
Authors: Zaker Manouchehr 
Published: March 2008

AbstractIn this article we first give an upper bound for the chromatic number of a graph in terms of its degrees. This bound generalizes and modifies the bound given in 11. Next, we obtain an upper bound of the order of magnitude ${\cal O}({n}^{{1}-\epsilon})$ for the coloring number of a graph with small K2,t (as subgraph), where n is the order of the graph. Finally, we give some bounds for chromatic number in terms of girth and book size. These bounds improve the best known bound, in terms of order and girth, for the chromatic number of a graph when its girth is an even integer. © 2008 Wiley Periodicals, Inc. J Graph Theory 58:110–122, 2008
Assessing the spatial and temporal variation in the skill of precipitation forecasts from an NWP model
Authors: Roberts Nigel 
Published: March 2008

AbstractIt is becoming increasingly important to be able to verify the spatial accuracy of precipitation forecasts, especially with the advent of high‐resolution numerical weather prediction (NWP) models. In this article, the fractions skill score (FSS) approach has been used to perform a scale‐selective evaluation of precipitation forecasts during 2003 from the Met Office mesoscale model (12 km grid length). The investigation shows how skill varies with spatial scale, the scales over which the data assimilation (DA) adds most skill, and how the loss of that skill is dependent on both the spatial scale and the rainfall coverage being examined. Although these results come from a specific model, they demonstrate how this verification approach can provide a quantitative assessment of the spatial behaviour of new finer‐resolution models and DA techniques. Copyright © 2008 Royal Meteorological Society
Simultaneous observation of glutamate, γ‐aminobutyric acid, and glutamine in human brain at 4.7 T using localized two‐dimensional constant‐time correlation spectroscopy
Authors: Watanabe H. , Takaya N. , Mitsumori F. 
Published: March 2008

AbstractLocalized two‐dimensional constant‐time correlation spectroscopy (CT‐COSY) was used to resolve glutamate (Glu), γ‐aminobutyric acid (GABA), and glutamine (Gln) in the human brain at 4.7 T. In this method, three‐dimensional localization was achieved using three radio frequency pulses of the CT‐COSY module for slice selection. As this sequence could decouple JHH along the F1 direction, peak resolution of metabolites was improved even on a magnitude‐mode display. In experiments on a phantom containing N‐acetylaspartate, creatine, Glu, Gln, and GABA with a constant time delay (Tct) of 110 ms, cross peaks of Glu, Gln, and GABA were obtained on a spectrum processed with standard sine‐bell windows, which emphasize sine‐dependent signals along the t2 direction. In contrast, diagonal peaks of Glu C4H at 2.35 ppm, GABA C2H at 2.28 ppm, and Gln C4H at 2.44 ppm were resolved on a spectrum processed with Gaussian windows, which emphasize cosine‐dependent signals along t2. Human brain spectra were obtained from a 27 mL voxel within the parieto‐occipital region using a volume transverse electromagnetic (TEM) coil for both transmission and reception. Tct was 110 ms; the total scan time was 30 min. Diagonal peaks of Glu C4H, GABA C2H, and Gln C4H were also resolved on the spectrum processed with Gaussian windows. These results show that the localized two‐dimensional CT‐COSY method featuring 1H decoupling along the F1 direction could resolve Glu, GABA, and Gln signals in the human brain. Copyright © 2008 John Wiley & Sons, Ltd.
Hyperbolicity, stability and monodromy of dynamical systems
Authors: Arai Zin 
Published: March 2008

AbstractWe propose a rigorous computational method for proving uniform hyperbolicity of dynamical systems. Besides finding structurally stable parameters, the algorithm can also be applied for the computation of the monodromy of dynamical systems. With this algorithm, we prove that the topology of the 2‐dimensional generalization of the Mandelbrot set is totally different from that of the original Mandelbrot set. Furthermore, we show that the monodromy of the complex Hénon map can be used to determine the dynamics of the real Hénon map. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Period‐doubling cascades and mode interactions in coupled systems
Authors: Aston P. J. , Mir H. 
Published: March 2008

AbstractSuppose that an iterated map exhibits a period‐doubling cascade. If two such maps are coupled, then the synchronised state will exhibit the same period‐doubling cascade but there is also the additional possibility of symmetry‐breaking bifurcations to non‐synchronised states. By introducing a second parameter, a symmetry‐breaking bifurcation and a period‐doubling bifurcation can be made to occur at the same point, resulting in a mode interaction.As the second parameter is varied from the value at the mode interaction, a second symmetry‐breaking bifurcation may occur from the period 2 solutions, which will then be involved in another mode interaction at the next period‐doubling bifurcation point. In this way, a complete cascade of mode interactions can occur.A local analysis of such a mode interaction is considered. The global consequences together with a classification of different cases are then analysed. Renormalisation theory is used to determine the universal behaviour and parameter scalings of such a system. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On the convergence of quasi‐random sampling importance resampling
Authors: Cools Ronald , Vandewoestyne Bart 
Published: March 2008

AbstractThe Sampling/Importance Resampling (SIR) algorithm can be used for generating representative point sets from a distribution known up to a multiplicative constant. Moreover, the Quasi‐random Sampling Importance Resampling (QSIR) scheme, based on quasi‐Monte Carlo methods, is a recent modification of the SIR algorithm and was empirically shown to have better convergence. We present error convergence results for QSIR that we obtained using quasi‐Monte Carlo theory. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Numerical solution of a variational problem with L∞ functionals
Authors: Parente Lisandro A. , Aragone Laura S. , Lotito Pablo A. , Reyero Gabriela F. 
Published: March 2008

AbstractWe consider the problem which consists in finding an optimal Lipschitz extension to the domain Ω of functions that verify the restriction u = g on ∂Ω. This work deals with the numerical approximations of the problem in dimension two. Using a discretization procedure based on finite differences method we obtain a large scale non smooth convex minimization problem, which is solved via Variable Metric Hibrid Proximal Point Method. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Clustering of point vortices in a periodic box
Authors: Umeki Makoto 
Published: March 2008

AbstractMotions of N point vortices with square periodic boundary conditions are studied numerically, where N is order of 100. The clustering property is examined by computing the L function familiar in the field of spatial ecology. The case of a positive value of L corresponds to the state of clustering and the Onsager's negative temperature. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Protein profile in neuroblastoma cells incubated with S‐ and R‐enantiomers of ibuprofen by iTRAQ‐coupled 2‐D LC‐MS/MS analysis: Possible action of induced proteins on Alzheimer's disease
Authors: Zhang Jianhua , Sui Jianjun , Ching Chi Bun , Chen Wei Ning 
Published: March 2008

AbstractIbuprofen is a member of the proprionic acid group of nonsteroidal anti‐inflammatory drugs (NSAID), with the S‐enantiomer being more active than the R‐enantiomer. It has been shown to display protective effects against neuroinflammation, which is linked to the pathogenesis of several neurodegenerative disorders, including Alzheimer's disease (AD). While its prophylactic effect on AD has been suggested, a comprehensive understanding of its mechanism of action remains unclear. Using iTRAQ‐coupled 2‐D LC‐MS/MS analysis, we report here the first study of protein profiles of neuroblastoma cells incubated separately with the two enantiomers of ibuprofen. Three types of cellular proteins, including metabolic enzymes, signaling molecules and cytoskeletal proteins, displayed changes. The changes in the level of a number of enzymes involved in fatty acid synthesis and antioxidant activity in cells incubated with the S‐enantiomer were further supported by the real‐time PCR analysis as well as the reduced level of reactive oxygen species in cells incubated with the S‐enantiomer of ibuprofen. Our findings, therefore, provide the possible mechanism of ibuprofen‐induced proteins on AD, and the beneficial effects of ibuprofen in reducing the development of AD.
The effect of low pH on protein expression by the probiotic bacterium Lactobacillus reuteri
Authors: Lee KiBeom , Lee Hong‐Gu , Pi KyungBae , Choi Yun‐Jaie 
Published: March 2008

AbstractThe ability of a lactic acid bacterium to survive passage through the gastrointestinal tract is a key point in its function as a probiotic. In this study, protein synthesis by the probiotic bacterium, Lactobacillus reuteri, was analyzed under transiently decreased pH conditions. L. reuteri cells grown to the midexponential growth phase at 37°C were exposed to transient (1 h) low‐pH stresses from pH 6.8 to pH 5.0, 4.5, or 4.0. 2‐DE allowed us to identify 40 common proteins that were consistently and significantly altered under all three low‐pH conditions. PMF was used to identify these 40 proteins, and functional annotation allowed them to be distributed to six major classes: (i) transport and binding proteins; (ii) transcription–translation; (iii) nucleotide metabolism and amino acid biosynthesis; (iv) carbon energy metabolism; (v) pH homeostasis and stress; and (vi) unassigned. These findings provide new insight into the inducible mechanisms underlying the capacity of gastrointestinal L. reuteri to tolerate acid stress.
Contact spotting of protein microarrays coupled with spike‐in of normalizer protein permits time‐resolved analysis of ERBB receptor signaling
Authors: Löbke Christian , Laible Mark , Rappl Claudia , Ruschhaupt Markus , Sahin Özgür , Arlt Dorit , Wiemann Stefan , Poustka Annemarie , Sültmann Holger , Korf Ulrike 
Published: March 2008

AbstractProtein microarrays allow highly accurate comparison and quantification of numerous biological samples in parallel while requiring only little material. This qualifies protein arrays for systems biology and clinical research where only limited sample material is available, but a precise readout is required. With the introduction of signal normalization steps to monitor the drop size of manually contact‐spotted RP protein arrays, the usefulness of normalizer proteins to ensure a high‐throughput but inexpensive protein analysis was demonstrated. This approach was applied for the analysis of signaling through ERBB receptor activated kinases in the breast cancer cell line MCF‐7. Activation of ERK1/2 and AKT by ERBB1 (EGFR), ERRB2 (HER2/neu), and ERBB3‐4 was monitored in a time‐resolved manner. Analysis of pathway activation by stimulation with epidermal growth factor and heregulin, or inhibition by blocking with gefitinib or herceptin allowed a characterization of the distinct signaling properties of the different ERBB receptor subtypes.
Uniaxial anisotropy of organic thin films determined by ellipsometry
Authors: Heinemeyer U. , Hinderhofer A. , Alonso M. I. , Ossó J. O. , Garriga M. , Kytka M. , Gerlach A. , Schreiber F. 
Published: March 2008

AbstractOrganic thin films frequently exhibit strong anisotropic optical constants, which in many cases are uniaxial with the optic axis oriented along the surface normal. The data analysis presented here to obtain the anisotropic optical constants of thin films on silicon substrates is based on the model system diindenoperylene (DIP), but nevertheless applies to all uniaxial films on SiO2. In addition to variable angle spectroscopic ellipsometry, different substrates are used to perform a multiple sample analysis. This way of analysing data increases the sensitivity to uniaxial anisotropy. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
In‐situ spectroscopic ellipsometry: optimization of monitoring and closed‐loop‐control procedures
Authors: Humlíček J. 
Published: March 2008

AbstractWe discuss optimized extraction of information contained in a series of complex reflectance ratios in a series of consecutive, in‐situ SE measurements during the growth of thin films. We present a general computational scheme and discuss guidelines for the optimum data treatment. As an example, we analyze several hundreds of spectra recorded during the growth of diamond‐like carbon on TiCN/steel substrate. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Application of transmission ellipsometry to the determination of CD spectra of porphyrin J‐aggregates solid‐state samples
Authors: Arteaga O. , El‐Hachemi Z. , Canillas A. 
Published: March 2008

AbstractTransmission‐mode perpendicular incidence phase modulated ellipsometry was applied to study anisotropic thin films of porphyrin J‐aggregates. A customized data acquisition system and measurement method was implemented to measure seven Mueller matrix elements, which allow us to determine the circular birefringence and dichroism as well as the linear birefringence and dichroism of solid‐state films. The examples shown illustrate the performance of the method for obtaining the true circular dichroism and consequently for detecting structural differences in chiral aggregates. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The anisotropic bond model of nonlinear optics
Authors: Adles E. J. , Aspnes D. E. 
Published: March 2008

AbstractThe anisotropic‐bond model (ABM) of nonlinear optics (NLO) provides a simple means of calculating NLO properties of materials by factoring the problem into four parts: first, determination of the local field at a bond‐charge site; second, solution of the anharmonic force equation of the bond charge; third, calculation of the radiation from the charge; and fourth, superposition of the radiation from all charges. Because this factorization is impossible in linear optics, this is one of the few cases where a nonlinear problem is simpler than its linear equivalent. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)