bluuebunny/crossref_metadata_2025_split huggingface dataset:
Myocardin‐related transcription factor B is required for normal mouse vascular development and smooth muscle gene expression
Authors: Wei Ke , Che Nam , Chen Fabian 
Published: December 2006

AbstractSmooth muscle gene expression is required for the proper development and function of multiple organ systems. Expression of smooth muscle genes is critical for contractile function and tissue architectural integrity. One critical transcription factor for smooth muscle gene expression is the Serum Response Factor (SRF). SRF is expressed ubiquitously, but tissue‐specific transcriptional regulation is conferred by its binding to cofactors such as myocardin. Myocardin‐related transcription factor B (MRTF‐B) is a member of a family of genes (Myocardin(Myocd),Myocardin‐related transcription factor A(MRTF‐A),MRTF‐B) that provides tissue‐specificity and potentiate SRF‐dependent transcription. Unlike myocardin, which is expressed specifically in smooth and cardiac muscle, MRTF‐B is expressed in a wide variety of tissues. To examine the function of MRTF‐B, we generated mice containing an insertional mutation of MRTF‐B. MRTF‐B homozygous mutants die in late gestation with vascular defects and liver hemorrhage. At E9.5, MRTF‐B is expressed strongly in the septum transversum mesoderm critical for development of the vitelline system that produces the liver sinusoids and portal venous system. MRTF‐B deficiency results in defective smooth muscle gene expression in the liver sinusoids, vitelline veins, and yolk sac, which contributes significantly to the lethal phenotype. These data support our hypothesis that MRTF‐B has a unique role in regulating smooth muscle genes important for liver, yolk sac, and portal vascular development. Developmental Dynamics 236:416–425, 2007. © 2006 Wiley‐Liss, Inc.
Mass Flow Balances of Triclosan in Small Rural Wastewater Treatment Plants and the Impact of Biomass Parameters on the Removal
Authors: Winkler G. , Thompson A. , Fischer R. , Krebs P. , Griffin P. , Cartmell E. 
Published: December 2006

AbstractThree United Kingdom (UK) wastewater treatment plants (WWTP) – rotating biological contactor (RBC), trickling filter (TF) and oxidation ditch (OD) – were analyzed for their triclosan contents at different treatment stages. Furthermore, selected wastewater and biomass parameters were determined to draw correlations between the biological treatment, biomass make‐up and the removal efficiency of triclosan. Within this study, triclosan bound to the extracellular polymeric substances (EPS) of sludge flocs in the oxidation ditch seemed to have an adverse effect on the effluent quality, reducing the triclosan overall removal due to re‐balancing effects within the final clarifier. Within this study of the three examined WWTPs, temperature and pH of the bulk phase and as well the lipid content of the biomass seemed to have the most significant effects on the triclosan removal. The triclosan overall removal for each site was shown to be significantly high, ranging on average between 81 % (RBC) and 96 % (OD). The most efficient plant regarding the triclosan overall removal was found to be the oxidation ditch, which can be explained due to high hydraulic retention times. Primary settling points were found to have a significant impact on the triclosan overall loss rate, which was associated with the high fat content of primary sludge and the hydrophobic properties of triclosan. Besides the fat content of sludge or biomass, the pH and temperature showed a significant impact on triclosan loss rates as well.
Spatial selectivity and theta phase precession in CA1 interneurons
Authors: Ego‐Stengel Valérie , Wilson Matthew A. 
Published: December 2006

AbstractTraditionally, most of the information processing of neural networks is thought to be carried out by excitatory cells. Likewise, recent evidence for temporal coding comes from the study of the detailed firing patterns of excitatory neurons. In the CA1 region of the rat hippocampus, pyramidal cells discharge selectively when the animal is in specific locations in its environment, and exhibit a precise relationship with the ongoing rhythmic activity of the network (phase precession). We demonstrate that during a spatial exploratory behavior on a linear track, inhibitory interneurons also show spatial selectivity and phase precession dynamics. We found that the firing rate of interneurons is modulated reliably up and down around an ongoing baseline activity level for specific locations in the environment, producing robust place‐specific increases or decreases in discharge. On some sections of the track, the range of theta phases shifts progressively to earlier parts of the theta cycle as the rat advances, so that a negative correlation between phase and position could be demonstrated. Unlike pyramidal cells, phase and rate were not strongly correlated. We discuss the influence of the intrinsic firing properties of interneurons on a model of phase precession, as well as the influence of the detailed shape of the inhibitory oscillation. These results indicate that spatial selectivity and phase precession in CA1 are not properties restricted to pyramidal cells. Rather, they may be a more general expression of a common interaction between the different inputs impinging on both excitatory and inhibitory cells in CA1 and the intrinsic characteristics of those cells. Furthermore, they suggest that the role of interneurons may extend beyond a global damping of the network by participating in a finely‐tuned local processing with the pyramidal cells. © 2006 Wiley‐Liss, Inc.
Mechanical properties and biological behavior of carbon nanotube/polycarbosilane composites for implant materials
Authors: Wang Wei , Watari Fumio , Omori Mamoru , Liao Susan , Zhu Yuhe , Yokoyama Atsuro , Uo Motohiro , Kimura Hisamichi , Ohkubo Akira 
Published: December 2006

AbstractMultiwalled carbon nanotube/polycarbosilane (MWCNT/PCS) composites were fabricated by the spark plasma sintering (SPS) method. The MWCNT/PCS composites consisted of MWCNTs and nanosized SiC particles pyrolyzed from PCS and possessing good mechanical properties for bone tissue repair or dental implantation. The MWCNT/PCS composites were implanted in the subcutaneous tissue and femur of rats at 1 and 4 weeks after implantation. Histological investigations showed that there was little inflammatory response in the subcutaneous tissue, and newly formed bone tissue was observed in the femur. These results indicated that the MWCNT/PCS composite had little prophlogistic effect and good osteoconductivity. The study suggested the possibility that the MWCNT/PCS composite could be a candidate bone‐substitute and dental‐implant material in the future. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 2006.
Hydroxyapatite moldable formulation using natural rubber latex as binder
Authors: Sailaja G. S. , Ramesh P. , Varma H. K. 
Published: December 2006

AbstractA simple but efficient processing method for shaping intricate bioceramic green bodies has been developed by using natural rubber latex as binder. Different shapes of hydroxyapatite Ca10(PO4)6(OH)2 (HAP) were molded from a composite formulation containing wet precipitated HAP, natural rubber latex (NRL), and a stabilizer. On controlled heat treatment followed by sintering, dense shapes of HAP contours were obtained. The thermal degradation profile of HAP–NRL composites shows that NRL degrades slowly without any abrupt exotherm. The results of energy dispersive X‐ray analysis together with inductively coupled plasma (ICP) analysis indicate that the inorganic residue of NRL does not contain any heavy element. The sintered density of the samples increased with increased HAP content in the formulation and percentage shrinkage reduced accordingly. On varying the HAP content in the formulation from 35 to 95 wt %, the compositions with 85, 90, 92, and 95 wt % HAP showed better flexural strength in the range 40–54 MPa and a flexural modulus value in the range 36–50 GPa. The fracture morphology, as observed by the scanning electron microscope confirms that with increased HAP content in the formulation the sample microstructure attains higher uniformity. The Vickers microhardness for the samples sintered at two different temperatures (1150 and 1250°C) showed that hardness increases with increase in the sintering temperature with a maximum for the highest HAP loaded formulation. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 2006.
Evaluation of DBM/AM composite as a graft substitute for posterolateral lumbar fusion
Authors: Qiu Qing‐Qing , Shih Mei‐Shu , Stock Kimberly , Panzitta Teri , Murphy Patricia A. , Roesch Sana C. , Connor Jerome 
Published: December 2006

AbstractDemineralized bone matrix (DBM) has been investigated as a bone graft substitute for spinal fusion with less morbidity. Various carriers have been added to DBM to enhance its handling characteristics. This study investigates the spinal fusion induced by a composite of DBM and acellular dermal matrix (AM) in comparison with autologous bone in an athymic rat spinal fusion model. Single‐level intertransverse process fusions were performed in 60 athymic nude rats grafted with 2 mL/kg of DBM/AM composite, AM alone, or autologous bone. Fusion was assessed at 6 weeks by radiography, manual palpation, and histology. At 6 weeks, 70% of the animals from the DBM/AM composite group exhibited complete spine fusion, whereas 35% from the autologous bone group and 20% from AM group showed bridging with some gaps. The DBM/AM composite induced a significantly higher fusion rate than both the autologous bone and AM groups (p << 0.001) in all measured parameters. The current study demonstrated that using DBM/AM composite can have more robust fusion than autologous bone at 6 weeks in an athymic rat spinal fusion model. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 2006.
Role of indenter material and size in veneer failure of brittle layer structures
Authors: Bhowmick Sanjit , Meléndez‐Martínez Juan José , Hermann Ilja , Zhang Yu , Lawn Brian R. 
Published: December 2006

AbstractThe roles of indenter material and size in the failure of brittle veneer layers in all‐ceramic crown‐like structures are studied. Glass veneer layers 1 mm thick bonded to alumina layers 0.5 mm thick on polycarbonate bases (representative of porcelain/ceramic‐core/dentin) are subject to cyclic contact loading with spherical indenters in water (representative of occlusal biting environment). Two indenter materials—glass and tungsten carbide—and three indenter radii—1.6, 5.0, and 12.5 mm—are investigated in the tests. A video camera is used to follow the near‐contact initiation and subsequent downward propagation of cone cracks through the veneer layer to the core interface, at which point the specimen is considered to have failed. Both indenter material and indenter radius have some effect on the critical loads to initiate cracks within the local Hertzian contact field, but the influence of modulus is weaker. The critical loads to take the veneer to failure are relatively insensitive to either of these indenter variables, since the bulk of the cone crack propagation takes place in the contact far field. Clinical implications of the results are considered, including the issue of single‐cycle overload versus low‐load cyclic fatigue and changes in fracture mode with loading conditions. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 2006.
Three new distal tephras in sediments spanning the Last Glacial–Interglacial Transition in Scotland
Authors: Pyne‐O'Donnell Sean D. F. 
Published: December 2006

AbstractThree new microtephras are reported from a number of lake sites from the Inner Hebrides and Scottish mainland. One occurs stratigrapically in the middle of Greenland Interstadial 1 (GI‐1) and has been named the Penifiler Tephra. It is rhyolitic and possesses a geochemical signature that is very similar to that of the Borrobol Tephra, which also occurs in three of the sequences reported here, but which lies close to the lower boundary of GI‐1. The second occurs stratigraphically in the early Holocene below the Saksunarvatn Ash and is named the Ashik Tephra. This tephra is geochemically bimodal, with a rhyolitic component comparable to the An Druim Tephra that occurs later in the Holocene, and a basaltic component which is similar to the Saksunarvatn Ash. A third tephra occurs stratigraphically above the Saksunarvatn Ash and is provisionally named the Breakish Tephra. The consistent inter‐site correlation demonstrated for these new tephras at several sites enhances the regional tephrostratigraphic framework, and increases the potential for correlating palaeoenvironmental events during GI‐1 and the early Holocene. However, the occurrence of multiple tephras with similar geochemistry in close stratigraphic and temporal proximity has implications for the rigour with which tephrostratigraphic investigations must be performed. Copyright © 2006 John Wiley & Sons, Ltd.
Fodder production and soil health with conjunctive use of saline and good quality water in ustipsamments of a semi‐arid region
Authors: Yadav R. K. , Singh S. P. , Lal D. , Kumar A. 
Published: December 2006

AbstractFood and fodder shortage in arid and semi‐arid regions force farmers to use marginal quality water for meeting the water requirement of crops which result in low quality, reduced production and an adverse impact on soil properties. A field study on loamy‐sand (Hyperthermic Typic Ustipsamments) saline soil was conducted during 1999–2001 at Central Institute for Research on Buffaloes, Hisar. This involved assessment of effects of conjunctive use of saline water, EC = 4·6–7·4 dSm−1, SAR = 14–22 ((mmol−1)½with good quality water on five fodder crop rotations: oat‐sorghum (Avena sativa‐–Sorghum bicolor), rye grass–sorghum (Loleum rigidum—Sorghum bicolor), Egyptian clover—sorghum (Trifoleum alexandrinum—Sorghum bicolor), Persian clover—sorghum (Trifoleum resupinatum—Sorghum bicolor) and Indian clover–sorghum (Melilotus indica—Sorghum bicolor) and certain soil properties associated with it. Leguminous winter fodder crops were more sensitive to poor quality water use. Reductions in fodder yield with use of saline water alone throughout season were 85, 68, 54, 42, 36 and 26 per cent in Indian clover, Egyptian clover, Persian clover, oat, rye grass and sorghum respectively as compared to good quality water. Leguminous fodder crops produced protein rich (12–14 per cent) and low fibre (18–20 per cent) fodder as compared to poor quality grassy fodder under good quality water irrigation but their quality deteriorated when saline water was used. These leguminous crops accumulated proportionately higher Na+(1·58 per cent) resulting in adverse impact on their growth as compared to grassy fodder crops. Higher soil salinity (12·2 dSm−1), SAR = 20 (mmol−1)½was recorded with saline water irrigation; and slight adverse impact was noticed on infiltration rate and contents of water dispersible clay. Alternate cyclic use of canal and saline water could be an option for fodder production under such conditions. Copyright © 2006 John Wiley & Sons, Ltd.
Participatory soil and water conservation planning using a financial analysis tool in the West Usambara highlands of Tanzania
Authors: Tenge A. J. , Okoba B. O. , Sterk G. 
Published: December 2006

AbstractDespite decades of soil and water conservation (SWC) efforts in Tanzania, the adoption of the recommended SWC measures by farmers is minimal. In the past, SWC plans did not incorporate farmers' knowledge, and the economics of SWC was not given much attention at the planning stage. This research evaluated the applicability of two tools for participatory soil erosion mapping using farmers' indicators of soil erosion and financial analysis of SWC measures at the planning stage. The two tools were evaluated in Kwalei catchment in the West Usambara highlands, Tanzania. The participatory soil erosion‐mapping tool uses farmers' indicators of soil erosion to identify, classify and map soil erosion at the catchment level. The financial analysis tool involves farmers in a stepwise analysis of the costs and benefits of SWC measures before the implementation. The erosion‐mapping tool increased farmers' awareness on the severity of soil erosion problems, and they realised the need for SWC plans at both field and catchment scales. With the financial analysis tool farmers participated in the cost and benefits analysis and were able to select SWC options that were feasible under their socio‐economic situation. The two tools were able to demonstrate that farmers' participation in SWC planning increases the acceptance of SWC measures because they solve problems that are perceived by themselves. The financial analysis tool demonstrated how farmers could make selection of SWC measures that are feasible under their biophysical and economic condition if they are informed about the costs and benefits. Copyright © 2006 John Wiley & Sons, Ltd.
On the point spectrum of ℋ︁–2‐singular perturbations
Authors: Albeverio Sergio , Dudkin Mykola , Konstantinov Alexei , Koshmanenko Volodymyr 
Published: December 2006

AbstractWe prove that for any self‐adjoint operator A in a separable Hilbert space ℋ︁ and a given countable set Λ = {λ i }i ∈ℕ of real numbers, there exist ℋ︁–2‐singular perturbations Ã of A such that Λ ⊂ σ p (Ã). In particular, if Λ = {λ 1,…, λ n } is finite, then the operator Ã solving the eigenvalues problem, Ã ψ k = λ k ψ k , k = 1,…, n, is uniquely defined by a given set of orthonormal vectors {ψ k }n k =1 satisfying the condition span {ψ k }n k =1 ∩ dom (|A |1/2) = {0}. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Cusps and codes
Authors: Barth Wolf P. , Rams Sławomir 
Published: December 2006

AbstractWe study a construction, which produces surfaces Y ⊂ ℙ3(ℂ) with cusps. For example we obtain surfaces of degree six with 18, 24 or 27 three‐divisible cusps. For sextics in a particular family of surfaces with up to 30 cusps the codes of these sets of cusps are determined explicitly. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Co‐rigidity of groups, von Neumann algebras and Kac algebras
Authors: Heo Jaeseong 
Published: December 2006

AbstractIn this paper, we consider a generalization of property T of Kazhdan for groups and property T of Connes for von Neumann algebras. We introduce another relative property T for groups corresponding to co‐rigidity for von Neumann algebras, which is different from relative property T of Margulis. We investigate the connection between a pair of von Neumann algebras and a pair of their commutants with respect to co‐rigidity. We define relative property T and co‐rigidity for a pair of Kac algebras as the generalizations of relative property T and co‐rigidity for groups. We show that the tensor product of two Kac algebras has property T if and only if two Kac algebras all have property T. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Branching rules for Hecke algebras of type Dn
Authors: Hu Jun 
Published: December 2006

AbstractIn this paper we study the branching problems for the Hecke algebra ℋ︁(D n ) of type D n . We explicitly describe the decompositions into irreducible modules of the socle of the restriction of each irreducible ℋ︁(D n )‐representation to ℋ︁(D n –1) by using the corresponding results for type B Hecke algebras. In particular, we show that any such restrictions are always multiplicity free. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A notion of Euler characteristic for fractals
Authors: Llorente Marta , Winter Steffen 
Published: December 2006

AbstractA notion of (average) fractal Euler number for subsets of ℝd with infinite singular complexes is introduced by means of rescaled Euler numbers of infinitesimal ε ‐neighbourhoods. For certain classes of self‐similar sets we calculate the associated Euler exponent and the (average) fractal Euler number with the help of the Renewal theorem. Examples like the Sierpinski gasket or carpet are provided. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Solutions to some nonlinear parabolic equations in pseudomeasure spaces
Authors: Miao Changxing , Yuan Baoquan 
Published: December 2006

AbstractIn this paper we study the Cauchy problem in pseudomeasure spaces for some nonlinear parabolic equations including nonlinear heat equations, nonlinear hyper‐dissipative equations, generalized nonlinear Hamilton–Jacobi equations, nonlinear hyper‐dissipative equations with convective term and the Ginzburg–Landau equation with third‐order nonlinear growth. We prove the existence, uniqueness and asymptotic stability of the global‐in‐time solutions for small initial data in some pseudomeasure spaces. As a result, the existence and uniqueness of selfsimilar solutions to the equations are obtained. Furthermore, with the self‐similar solutions of the equations, the long time behavior of solutions to the problem are also discussed. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Integrable operators and canonical differential systems
Authors: Sakhnovich Lev 
Published: December 2006

AbstractIn this article we consider a class of integrable operators and investigate its connections with the following theories: the spectral theory of the non‐self‐adjoint operators, the Riemann‐Hilbert problem, the canonical differential systems, the random matrices theory and the limit values of the multiplicative integral. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Theoretical and Experimental Investigation of the Production of PMMA‐Based Bone Cement
Authors: Santos Jorge G. F. , Peixoto Luciana S. , Nele Márcio , Melo Príamo A. , Pinto José Carlos 
Published: December 2006

AbstractPoly(methyl methacrylate) (PMMA)‐based polymers have been extensively used for manufacturing of artificial bone cements for treatment of osteoporosis. A typical bone cement recipe contains methyl methacrylate, which polymerizes in situ during cement application. An inherent problem of this reaction is the high amount of heat released during the cement preparation, which may lead to irreparable damage of living tissues. Optimization of PMMA‐based bone cement (PMMABC) recipes is thus an important step towards safe and reliable clinical usage of these materials. A theoretical and experimental investigation is performed here to unveil the influence of some preparation variables on the production of PMMABC and to allow for future optimization of the PMMABC recipe. It is shown that the degree of mixing of the components of the recipe plays a fundamental role on the development of the temperature profile. For this reason, the PMMABC obtained with the in‐situ blending of PMMA and barium sulfate during the suspension polymerization leads to much better homogeneity of the final test pieces and improved control of the temperature profile.
Modeling Methyl Methacrylate (MMA) Polymerization for Bone Cement Production
Authors: Lemos Lívia , Nele Marcio , Melo Príamo , Pinto José Carlos 
Published: December 2006

AbstractBone cements based on poly(methyl methacrylate) (PMMA) have been widely used in orthopedic surgeries for fixation of prostheses and filling of bone defects. Bone cements are produced through in situ and in vivo free radical bulk polymerizations, which are highly exothermic and are subject to strong gel and glass effects. As a consequence, high temperatures may be reached during application. Furthermore, residual monomer usually remains unreacted inside the body and may cause aseptic loosening and tissue damages.1 In a companion work in this volume, it was shown that usual free‐radical polymerization models might effectively describe the bone cement preparation2 and therefore be used for quantitative analysis of the bone cement synthesis. In this work, a theoretical investigation based on a multicell reactor model is performed to study the bone cement production and allow for future optimization of the preparation procedure. It is shown that the degree of solubility of the pre‐polymer powder in the liquid monomer is the most important variable during the bone cement preparation and that this variable should be manipulated for design and control of the operation in real applications.