bluuebunny/crossref_metadata_2025_split huggingface dataset:
On the relationship between hydrographs and chemographs
Authors: Kurtenbach Andreas , Möller Steffen , Krein Andreas , Symader Wolfhard 
Published: August 2006

AbstractThe spatial representativeness of gauging stations was investigated in two low‐mountainous river basins near the city of Trier, southwest Germany. Longitudinal profiles during low and high flow conditions were sampled in order to identify sources of solutes and to characterize the alteration of flood wave properties during its travel downstream. Numerous hydrographs and chemographs of natural flood events were analysed in detail. Additionally, artificial flood events were investigated to study in‐channel transport processes.During dry weather conditions the gauging station was only representative for a short river segment upstream, owing to discharge and solute concentrations of sources contiguous to the measurement site. During artificial flood events the kinematic wave velocity was considerably faster than the movement of water body and solutes, refuting the idea of a simple mixing process of individual runoff components. Depending on hydrological boundary conditions, the wave at a specific gauge could be entirely composed of old in‐channel water, which notably reduces the spatial representativeness of a sampling site. Natural flood events were characterized by a superimposition of local overland flow, riparian water and the kinematic wave process comprising the downstream conveyance of solutes. Summer floods in particular were marked by a chronological occurrence of distinct individual runoff components originating only from a few contributing areas adjacent to the stream and gauge. Thus, the representativeness of a gauge for processes in the whole basin depends on the distance of the nearest significant source to the station. The consequence of our study is that the assumptions of mixing models are not satisfied in river basins larger than 3 km2. Copyright © 2006 John Wiley & Sons, Ltd.
Predicting rainfall intensity using a genetic algorithm approach
Authors: Karahan Halil , Ceylan Halim , Tamer Ayvaz M. 
Published: August 2006

AbstractA genetic algorithm rainfall intensity (GARI) model has been developed and used to predict the intensities for given return period. It is a one‐step solution procedure that may not require any mathematical transformation. The problem formulation is given and the genetic algorithm solution of the problem is presented. The results show that the proposed GARI model can be used to solve the rainfall intensity–duration–frequency relations with lowest mean‐squared error between measured and predicted intensities. Predicted intensities are in good agreement between measured and predicted values for given return periods. Copyright © 2006 John Wiley & Sons, Ltd.
FAP‐1‐mediated activation of NF‐κB induces resistance of head and neck cancer to fas‐induced apoptosis
Authors: Wieckowski Eva , Atarashi Yoshinari , Stanson Joanna , Sato Taka‐Aki , Whiteside Theresa L. 
Published: August 2006

AbstractMolecular mechanisms responsible for tumor resistance to apoptosis often involve the Fas/FasL pathway. While squamous cell carcinomas of the head and neck (SCCHN) express both Fas and FasL, their resistance to self‐induced apoptosis or apoptosis mediated by Fas agonistic antibody (CH‐11Ab) was independent of the level of Fas surface expression or the presence of soluble Fas in supernatants of primary or metastatic SCCHN cell lines. By in vitro immunoselection, using PCI‐15A cell line treated with successive cycles of CH‐11 Ab, Fas‐resistant sublines with the parental genotype were selected. Such sublines failed to cleave caspase‐8 upon Fas engagement and were resistant to CH‐11 Ab, although they remained sensitive to VP‐16 or staurosporin. In the presence of cycloheximide, the selected SCCHN sublines become susceptible to CH‐11 Ab, and showed cleavage of caspase‐8, suggesting that apoptosis resistance was mediated by an inhibitory protein(s) acting upstream of caspase‐8. Overexpression of Fas‐associated phosphatase 1 (FAP‐1), but not cellular FLICE‐inhibitory protein (cFLIP) in SCCHN sublines was documented by Western blots and RT‐PCR analyses. The FAP‐1+ selected sublines also downregulated cell surface Fas. A high phosphorylation level of IκBκ, NFκB activation and upregulation of Bcl‐2 expression were observed in the FAP‐1+ sublines. Treatment with the phosphatase inhibitor, orthovanadate, or silencing of FAP‐1 with siRNA abolished their resistance to apoptosis, suggesting that FAP‐1 phosphatase activity could be responsible for NF‐κB activation and resistance of SCCHN cells to Fas‐mediated apoptosis. J. Cell. Biochem. 100: 16–28, 2007. © 2006 Wiley‐Liss, Inc.
High affinity of anti‐GM1 antibodies is associated with disease onset in experimental neuropathy
Authors: Comín Romina , Yuki Nobuhiro , Lopez Pablo H.H. , Nores Gustavo A. 
Published: August 2006

AbstractHigh antibody affinity has been proposed as a disease determinant factor in neuropathies associated with anti‐GM1 antibodies. An experimental model of Guillain‐Barré syndrome, induced by immunization of rabbits with bovine brain gangliosides or GM1, was described recently (Yuki et al. [2001] Ann. Neurol. 49:712–720). We searched plasma from these rabbits, taken at disease onset and 1 or 2 weeks prior to onset, for the presence of high‐affinity anti‐GM1 IgG antibodies. Affinity was estimated by soluble antigen binding inhibition. High‐affinity antibodies (binding inhibition by 10–9 M GM1) were detected at disease onset but not before. No such difference was found for other antibody parameters such as titer, fine specificity, and population distribution. These findings support the proposed role of high affinity as an important factor in disease induction by anti‐GM1 antibodies. © 2006 Wiley‐Liss, Inc.
NADPH oxidase inhibitor diphenyliodonium abolishes lipopolysaccharide‐induced down‐regulation of transferrin receptor expression in N2a and BV‐2 cells
Authors: Reis Katarina , Hälldin Jonas , Fernaeus Sandra , Pettersson Christina , Land Tiit 
Published: August 2006

AbstractThe activation of cellular inflammatory response is tightly linked to induced production of reactive oxygen species (ROS) and nitric oxide (NO), which in turn have been identified as important regulators of cellular iron metabolism. In the present study, we have used the microglia cell line BV‐2 and the neuroblastoma cell line N2a to study the regulatory effects of the microbial agent lipopolysaccharide (LPS) on the expression of the transferrin receptor (TfR) and ferritin in cell lines with different characteristics. The receptor mainly responsible for LPS recognition is the Toll‐like receptor 4 (TLR4) that triggers a variety of intracellular signalling cascades leading to the induction of transcription of target genes involved in the innate immune response. Among the pathways to be activated is the MAPK cascade leading to the activation of nuclear factor‐κB that induces transcription of a variety of genes, e.g., inducible nitric oxide synthase (iNOS). The TLR4‐mediated LPS response also induces the production of ROS through a mechanism(s) suggested to involve the activation of NADPH oxidase(s). This study shows that exposure of BV‐2 and N2a cells to LPS results in decreased TfR protein levels and increased H‐ferritin mRNA levels. The LPS down‐regulatory effect on TfR protein expression is abolished by the NADPH oxidase inhibitor diphenyliodonium (DPI) but is not affected by the free radical scavenger N‐acetyl‐L‐cysteine (NAC) or the iNOS inhibitor aminoguanidine (AG). The increased H‐ferritin mRNA levels in response to LPS are not affected by DPI, NAC, or AG. © 2006 Wiley‐Liss, Inc.
IL‐1β, an immediate early protein secreted by activated microglia, induces iNOS/NO in C6 astrocytoma cells through p38 MAPK and NF‐κB pathways
Authors: Kim Yun‐Jung , Hwang So‐Young , Oh Eok‐Soo , Oh Seikwan , Han Inn‐Oc 
Published: August 2006

AbstractIn the present study we sought to examine cell–cell interactions by investigating the effects of factors released by stimulated microglia on inducible nitric oxide (NO) synthase (iNOS) induction in astrocytoma cells. After examining the temporal profiles of proinflammatory molecules induced by lipopolysaccharide (LPS) stimulation in BV2 microglial cells, iNOS and IL‐1β were observed to be the first immediate‐response molecules. Removal of LPS after 3 hr stimulation abrogated NO release, whereas a full induction of IL‐1β was retained in BV2 cells. We observed consistently that conditioned medium (CM) from activated microglia resulted in the induction of iNOS in C6 cells, and IL‐1β was shown to be a key regulator of iNOS induction. An IL‐1β‐neutralizing antibody diminished NO induction. Incubation with recombinant IL‐1β stimulated NO release to a lesser extent compared to microglial CM; co‐treatment of LPS and IL‐1β had a potent, synergistic effect on NO release from C6 cells. Transient transfection with MEK kinase 1 (MEKK1) or nuclear factor‐kappa B (NF‐κB) expression plasmids induced iNOS, and IL‐1β further enhanced the MEKK1 response. Furthermore, IL‐1β‐mediated NO release from C6 cells was significantly suppressed by inhibition of p38 mitogen activated protein kinase (MAPK) or NF‐κB by specific chemical inhibitors. Both IL‐1β and MEKK1 stimulated p38 and JNK MAPKs, as well as the NF‐κB pathway, to induce iNOS in C6 cells. Microglia may represent an anti‐tumor response in the central nervous system, which is potentiated by the local secretion of immunomodulatory factors that in turn affects astrocytoma (glioma) cells. A better understanding of microglia–glioma or microglia–astrocyte interactions will help in the design of novel immune‐based therapies for brain tumors or neuronal diseases. © 2006 Wiley‐Liss, Inc.
Differential sensitivity of Desi (small‐seeded) and Kabuli (large‐seeded) chickpea genotypes to water stress during seed filling: effects on accumulation of seed reserves and yield
Authors: Nayyar Harsh , Kaur Satwinder , Singh Smita , Upadhyaya Hari D 
Published: August 2006

AbstractWater stress during the reproductive phase, especially during seed development, is considered detrimental for chickpea yield. In the present study, the relative sensitivity of Desi and Kabuli chickpea types to water stress during seed filling was assessed in terms of effects on quantitative and qualitative aspects of seed yield. Leaves of both types experienced stress injury (evaluated as electrolyte leakage) to the same extent and possessed almost similar values of water potential at the end of 14 days of water stress. The stressed plants of Kabuli type lost more chlorophyll and had less photosynthesis than Desi type. At maturity, Desi type showed more diminution of vegetative dry matter due to stress over control than Kabuli type. On the other hand, Kabuli type showed a proportionally greater reduction in seed weight per plant, average seed weight, average seed size, number of pods (single‐ and double‐seeded) and harvest index. The stressed seeds of Kabuli type showed 48 and 46% reduction over control in starch and protein content compared with 25 and 40%, respectively in Desi type. The accumulation of soluble sugars was relatively greater due to stress in Kabuli (47%) than Desi type (23%). Fat and fiber content declined by 39 and 35% over control in Desi seeds because of stress whereas Kabuli type showed 46 and 67% decreases, respectively. Protein fractions, namely albumins, globulins, glutelins and prolamins, decreased in stressed seeds of Kabuli by 32, 40, 16 and 15% over control relative to 40, 48, 30 and 28%, respectively, in Kabuli type. The activities of sucrose synthase, invertase and soluble starch synthase were inhibited to a higher extent in Kabuli seeds than Desi seeds under stress. Kabuli seeds showed significantly more reduction in the accumulation of amino acids such as phenylalanine + tyrosine, tryptophan, valine, alanine and histidine and minerals (Ca, P, Fe) due to stress compared with Desi type. Copyright © 2006 Society of Chemical Industry
High‐performance liquid chromatographic enantioseparations on capillary columns containing crosslinked polysaccharide phenylcarbamate derivatives attached to monolithic silica
Authors: Chankvetadze Bezhan , Kubota Takateru , Ikai Tomoyuki , Yamamoto Chiyo , Kamigaito Masami , Tanaka Nobuo , Nakanishi Kazuki , Okamoto Yoshio 
Published: August 2006

AbstractMonolithic capillary columns containing native silica gel were covalently modified with 3,5‐disubstituted phenylcarbamate derivatives of cellulose and amylose and applied for enantioseparations in capillary LC. The method previously used for covalent immobilization of polysaccharide phenylcarbamate derivatives onto the surface of microparticulate silica gel was successfully adapted for in situ modification of monolithic fused‐silica capillary columns. The effects of the nature of polysaccharide and the substituents, as well as of multiple covalent immobilization of polysaccharide derivative on chromatographic performance of capillary columns were studied. The capillary columns obtained using this technique are stable in all solvents commonly used in LC and exhibit promising enantiomer resolving ability.
Determination of anatoxin‐a in environmental water samples by solid‐phase microextraction and gas chromatography‐mass spectrometry
Authors: Rodríguez Vania , Yonamine Mauricio , Pinto Ernani 
Published: August 2006

AbstractIn the present work, a method was developed and optimized aiming at the determination of anatoxin‐a in environmental water samples. The method is based on the direct derivatization of the analyte by adding hexylchloroformate in the alkalinized sample (pH = 9.0). The derivatized anatoxin‐a was extracted by a solid‐phase microextraction (SPME) procedure, submersing a PDMS fiber in an amber vial for 20 min under magnetic stirring. GC‐MS was used to identify and quantify the analyte in the SIM mode. Norcocaine was used as internal standard. The following ions were chosen for SIM analyses (quantification ions in italics): anatoxin‐a: 191, 164, 293 and norcocaine: 195, 136, 168. The calibration curve showed linearity in the range of 2.5–200 ng/mL and the LOD was 2 ng/mL. This method of SPME and GC‐MS analysis can be readily utilized to monitor anatoxin‐a for water quality control.
Approaching the Proteoglycome: Molecular Interactions of Proteoglycans and Their Functional Output
Authors: Cattaruzza Sabrina , Perris Roberto 
Published: August 2006

AbstractSummary: Through their diverse core protein modules and glycan/glycosaminoglycan moieties, proteoglycans may engage in numerous cellular and molecular interactions which are dispensable during embryogenesis, are essential for the maintenance of a healthy state and are prone to modulation in pathological conditions. Proteoglycan interactions may involve binding to other structural components of the ECM, to cell surface receptors, to membrane‐associated components, and to soluble signaling molecules, which through this interaction may become entrapped in the ECM or sequestered at the cell surface. Understanding of these multiple interplays is therefore of paramount importance and requires a detailed mapping through what we define as the proteoglycome.
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Fast frequency response analysis of large‐scale structures with non‐proportional damping
Authors: Kim Chang‐Wan , Bennighof J. K. 
Published: August 2006

AbstractModal frequency response analysis is an economical approach for large and complex structural systems since there is an enormous reduction in dimension from the finite element frequency response problem. However, when non‐proportional damping exists, the modal frequency response problem is expensive to solve at many frequencies because modal damping matrices are fully populated. This paper presents a new algorithm to solve the modal frequency response problem for large and complex structural systems with structural and viscous damping. The newly developed algorithm, fast frequency response analysis (FFRA) algorithm, solves the damped modal frequency response problem with O(m2) operations at each frequency. Then the FFRA algorithm is extended for solving a system of equations in optimization application with the modal correction approach, in which the mass, stiffness and damping matrices of a modified configuration differ from the original configuration. Numerical results show that the FFRA algorithm dramatically improves the performance of the modal frequency response analysis compared to conventional methods in industry while obtaining the same accuracy. Copyright © 2006 John Wiley & Sons, Ltd.
Phase‐field modelling of solidification microstructure formation using the discontinuous finite element method
Authors: Shu Y. , Ai X. , Li B. Q. 
Published: August 2006

AbstractThis paper presents a discontinuous Galerkin finite element computational methodology for solving the coupled phase‐field and heat diffusion equations to predict the microstructure evolution during solidification. The phase‐field modelling of microstructure formation is briefly discussed. The discontinuous Galerkin finite element formulation for the phase‐field model systems for solidification microstructure formation is described in detail. Numerical stability is performed using the Neumann method. The accuracy of the discontinuous model is verified by the analytic solution of a simple 1‐D solidification problem. Numerical calculations using the discontinuous finite element phase‐field model have been performed for simulating the complex 2‐D and 3‐D dendrite structures formed in supercooled melts and the results are compared well with those in literature using the finite difference methods. Parallel computing algorithm is presented and results show that the minimization of the intercommunication between microprocessors is the key to increase the effectiveness in parallel computing with the discontinuous finite element phase‐field model for solidification microstructure formation. Copyright © 2006 John Wiley & Sons, Ltd.
Application of hybrid Trefftz finite element method to non‐linear problems of minimal surface
Authors: Wang Hui , Qin Qing‐Hua , Arounsavat Detdexa 
Published: August 2006

AbstractThis investigation provides a hybrid Trefftz finite element approach for analysing minimal surface problems. The approach is based on combining Trefftz finite element formulation with radial basis functions (RBF) and the analogue equation method (AEM). In this method, use of the analogue equation approach avoids the difficulty of treating the non‐linear terms appearing in the soap bubble equation, making it possible to solve non‐linear problems with the Trefftz method. Global RBF is used to approximate the inhomogeneous term induced from non‐linear functions and other loading terms. Finally, some numerical experiments are implemented to verify the efficiency of this method. Copyright © 2006 John Wiley & Sons, Ltd.
Topology optimization of regions of Darcy and Stokes flow
Authors: Wiker Niclas , Klarbring Anders , Borrvall Thomas 
Published: August 2006

AbstractThis paper treats the topology optimization problem of obtaining an optimal layout of regions of Darcy and Stokes flow, where the objective is the total potential power functional representing average fluid pressure. It extends the work of Borrvall and Petersson, which concerned optimal layout of Stokes flow only. A generalization of Stokes' equations is derived and used as state constraints in the optimization problem. A proof of existence of solutions is provided, and it is seen that although the corresponding proof in Borrvall and Petersson does not need regularization, the present one does. It is also concluded that linear interpolations of state parameters will result in black and white (unfiltered) designs. The method is tested on an area‐to‐point flow problem of the type discussed by Bejan, where the influence of various parameters and numerical strategies on the design are studied. Copyright © 2006 John Wiley & Sons, Ltd.
Solution of periodic group circular hole problems by using the series expansion variational method
Authors: Chen Y. Z. , Lin X. Y. 
Published: August 2006

AbstractThis paper investigates the periodic group circular holes composed of infinite groups with numbering fromj= − ∞, …, −2, −1, 0, 1, 2, … toj= ∞ placed periodically in an infinite plate. The same loading condition and the same geometry are assumed for holes in all groups. The series expansion variational method (SEVM) is used for the solution of the periodic group circular hole problems. After using the SEVM, the boundary value problem is then reduced to an algebraic equation for the undetermined coefficients in the series expansion form, which is formulated on the central group. The influences on the central group from central group itself and many neighbouring groups are evaluated exactly. The influences on the central group from remote groups fromj= − ∞, −(M+ 2), −(M+ 1),M+ 1,M+ 2 toj= ∞ are approximately summed up into one term. This suggested technique is called the remainder estimation technique (RET) hereafter. It is proved from the computed results that the RET is very effective for the solution of the periodic group hole problems. Finally, several numerical examples are given and the interaction between the groups is addressed. Comparison between various sources of computation is presented. In the uniaxial tension iny‐direction, the stacking effect of the stacked groups is studied. Copyright © 2006 John Wiley & Sons, Ltd.
A wet‐road braking distance estimate utilizing the hydroplaning analysis of patterned tire
Authors: Cho J. R. , Lee H. W. , Yoo W. S. 
Published: August 2006

AbstractA wet‐road braking distance estimate for the vehicles equipped with ABS (anti‐lock brake system) is presented in this paper. The entire speed interval at braking is divided into several uniform sub‐intervals, and the energy conservation law is applied to individual sub‐intervals to predict the intervalwise braking times and the resulting velocity profile at braking and the total braking distance. The proposed method is based on a numerical‐analytical approach such that the frictional energy loss of the patterned tire is computed by 3‐D hydroplaning analysis while the other at the disc pad is analytically derived. The operation of ABS is numerically implemented by controlling the tire angular velocity such that the preset tire slip ratio on the wet road is maintained. The tire hydroplaning is analysed by generally coupling an Eulerian finite volume method and an explicit Lagrangian finite element method. Illustrative numerical experiment is presented to support the validity of the proposed estimate. Copyright © 2006 John Wiley & Sons, Ltd.
Eigensolution for free vibration of planar frames by weighted graph symmetry
Authors: Kaveh A. , Dadfar B. 
Published: August 2006

AbstractIn this paper, the method recently developed for mass‐spring systems is generalized to include the free vibration of frames. Here, the inter‐relation for the mechanical properties of elements is established using weighted graphs, enabling the calculation of the eigenvalues involved. Using graph symmetry, the models are decomposed into submodels and healing processes are employed such that the union of the eigenvalues of the healed submodels results in the eigenvalues of the entire model. The present method is illustrated through many simple examples of different configurations. Copyright © 2006 John Wiley & Sons, Ltd.