bluuebunny/crossref_metadata_2025_split huggingface dataset:
Signaling proteins in the axoglial apparatus of sciatic nerve nodes of Ranvier
Authors: Toews Joanna C. , Schram Vincent , Weerth Susanna H. , Mignery Gregory A. , Russell James T. 
Published: November 2006

AbstractDuring action potential conduction, the axonal specializations at the node, together with the adjacent paranodal terminations of the myelin sheath, interact with glial processes that invest the nodal gap. The nature of the mutual signals between axons and myelinating glia, however, are not well understood. Here we have characterized the distribution of inositol 1,4,5‐trisphosphate receptors (IP3Rs) in the axoglial apparatus by immunohistochemistry, using known myelin domain‐specific markers. While IP3R1 is not expressed in the Schwann cells or the axon, IP3R2 and IP3R3 are expressed in distinct cellular domains, suggesting distinct signaling roles for the two receptors. IP3R3 is the most predominant isoform in Schwann cells, and is expressed in particularly dense patches in the paranodal region. In addition to IP3Rs, two other members of the metabotropic Ca2+ signaling pathway, Gαq, and P2Y1 type of purinoceptors were also found in Schwann cells. Their pattern of expression matches the expression of their signaling partners, the IP3Rs. One interesting finding to emerge from this study is the expression of connexin 32 (Cx32) in close proximity with IP3R3. Although IP3R3 and Cx32 are not colocalized, their expression in the same membrane areas raises the question whether Schwann cell Ca2+ signals either control the function of the gap junctions, or whether the gap junctional channels serve as conduits for rapid radial spread of Ca2+ signals initiated during action potential propagation. Published 2006 Wiley‐Liss, Inc.
Expression of tranferrin receptors in the pineal gland of postnatal and adult rats and its alteration in hypoxia and melatonin treatment
Authors: Kaur C. , Sivakumar V. , Ling E. A. 
Published: November 2006

AbstractTransferrin receptors (Tfrc) are membrane bound glycoproteins which function to mediate cellular uptake of iron from transferrin. We examined expression of Tfrc in the pineal gland of rats of different ages from 1 day to 12 weeks. The mRNA and protein expression of Tfrc increased up to 6 weeks of age and decreased in 12 week rats. Tfrc immunoreactivity was observed on pinealocytes and macrophages/microglia. By immunoelectron microscopy, the immunoreaction in pinealocytes was observed in the cytosol, on mitochondria and plasma membrane whereas in macrophages/microglia it was localized on the plasma membrane in 1‐day to 2‐week old rats. In older rats, the immunoreaction product in pinealocytes was associated with the plasma membrane and mitochondria only. Iron localization was observed in pinealocytes as well as macrophages/microglia. It is suggested that Tfrc are required for uptake of iron for cell proliferation and maturation in the pineal gland upto 6 weeks of age. The significance of Tfrc expression on mitochondria is speculative. They may be involved in iron transport to the mitochondria or for regulation of the secretory activity of pinealocytes. The TfrcmRNA and protein expression increased significantly in response to hypoxia in 12‐week rats and this coincided with intense iron staining of the pinealocytes and macrophages/microglia. It is concluded that increased expression of Tfrc in response to hypoxia leads to excess cellular uptake of iron which may be damaging to the cells. Melatonin administration in hypoxic rats may prove to be beneficial as it reduced the Tfrc expression. © 2006 Wiley‐Liss, Inc.
Modelling multi‐period inflation uncertainty using a panel of density forecasts
Authors: Lahiri Kajal , Liu Fushang 
Published: November 2006

AbstractThis paper examines the determinants of inflation forecast uncertainty using a panel of density forecasts from the Survey of Professional Forecasters (SPF). Based on a dynamic heterogeneous panel data model, we find that the persistence in forecast uncertainty is much less than what the aggregate time series data would suggest. In addition, the strong link between past forecast errors and current forecast uncertainty, as often noted in the ARCH literature, is largely lost in a multi‐period context with varying forecast horizons. We propose a novel way of estimating ‘news’ and its variance using the Kullback‐Leibler information, and show that the latter is an important determinant of forecast uncertainty. Our evidence suggests a strong relationship of forecast uncertainty with level of inflation, but not with forecaster discord or with the volatility of a number of other macroeconomic indicators. Copyright © 2006 John Wiley & Sons, Ltd.
Health insurance and retirement of married couples
Authors: Blau David M. , Gilleskie Donna B. 
Published: November 2006

AbstractMost health insurance in the USA is provided by employers until eligibility for public health insurance (Medicare) begins at age 65. Retiring before 65 exposes workers who lack retiree health insurance coverage to the risk of catastrophic medical expenditure. We solve and estimate a dynamic model of the employment behavior of older married couples that includes risky medical expenditure and health insurance. Parameter estimates imply that the risk‐reducing feature of health insurance can account for about half of the observed association between retiree health insurance and employment for married men, but can account for only one tenth of the much larger observed association for married women. Policy simulations imply very small effects on employment of changing the age of eligibility for Medicare from 65 to 67. Copyright © 2006 John Wiley & Sons, Ltd.
Sensitivity of regional climatic simulation over Southeastern South America to SST specification during austral summer
Authors: Cuadra Santiago Vianna , da Rocha Rosmeri Porfírio 
Published: November 2006

AbstractThe impact of the sea‐surface temperature (SST) specification over the South Atlantic Ocean on the interannual variability of the simulated precipitation and air temperature over Southeastern South America (SESA) was studied during ten austral summers, from 1989 to 1998, using the Regional Climate Model version 3 (RegCM3), driven by the National Centers for Environmental Prediction (NCEP) reanalysis. The analyses were performed by comparing simulations forced with: (1) monthly observed SST (OSST); (2) SST composed by the persistence of November SST anomalies superimposed on the climatological observed cycle (persisted SST‐PSST). The results show that, over the continental SESA, the PSST impact is low on the simulated seasonal precipitation and air temperature climatologies. Furthermore, the interannual seasonal anomalies in this area do not change sign as a function of the prescribed SST. This is very important since it shows that, on a seasonal timescale, the use of PSST over the subtropical South Atlantic does not introduce additional error source in the regional model simulations over the continental SESA. Over the Atlantic Ocean, mainly in the region where the South Atlantic Convergence Zone (SACZ) acts, the simulations presented a direct response as a function of the SST, i.e. if the PSST is warmer (colder) than the OSST, the seasonal precipitation increases (decreases).Ensemble simulations of a particular summer showed that the deviation introduced by PSST is of the same intensity of the model internal variability and the use of five members ensemble‐mean eliminates the differences between OSST and PSST experiments over continental SESA. However, this result cannot be applied over the subtropical South Atlantic Ocean, where the differences were not eliminated by calculating the ensemble‐mean, showing a signal generated by the prescribed SST. Copyright © 2006 Royal Meteorological Society
On the critical values of the standard normal homogeneity test (SNHT)
Authors: Khaliq M. N. , Ouarda T. B. M. J. 
Published: November 2006

AbstractThe use of the standard normal homogeneity test (SNHT) for homogenization of climatological records and studying changes in their patterns has increased in recent years. The critical values of this test were originally developed for sample sizes ranging from 10 to 250 using relatively short Monte Carlo simulations (MCS). The objective of this paper is to improve the critical values of the SNHT and extend them to large sample sizes. The critical values, along with their standard errors, are developed for 108 sample sizes ranging from 10 to 50 000 using 30 replicates of one million samples for each sample size. These critical values mimic the tails of the SNHT statistic better and therefore are more accurate, and would be useful for making correct statistical inference for climate data homogenization and assessment of climate variability in future studies. Copyright © 2006 Royal Meteorological Society
Eukaryotic initiation factor 4E variants alter the morphology, proliferation, and colony‐formation properties of MDA‐MB‐435 cancer cells
Authors: Goldson Tovë M. , Vielhauer George , Staub Eveline , Miller Steve , Shim Hyunsuk , Hagedorn Curt H. 
Published: November 2006

AbstractEukaryotic initiation factor 4E (eIF4E) binds to the 5′ m7G cap of mRNAs and is a focal point of regulation of initiation of mRNA translation. High levels of expression of eIF4E in many epithelial cancers, including breast, head and neck, colon, and bladder, correlate with increased tissue invasion and metastasis. To further examine the role of eIF4E in the biology of cancer cells, variants of eIF4E with impaired 5′ cap binding function were expressed in MDA‐MB‐435 carcinoma cells. Cell lines overexpressing variants of eIF4E had impaired growth properties and exhibited a different morphology compared to cells expressing similar amounts of exogenous wild‐type eIF4E or control cells. Cells expressing variant eIF4E did not form foci in culture and produced smaller colonies in soft agar compared to cells expressing wild‐type eIF4E. In addition, analysis of polyribosomes for vascular endothelial growth factor (VEGF) mRNA demonstrated a shift from translationally active to inactive fractions in variant eIF4E cells, while GAPDH mRNA did not. The long G‐C rich 5′ untranslated region of VEGF mRNA is a feature of other mRNAs encoding growth regulating proteins that are predicted to have their translation enhanced by increases in eIF4E; whereas mRNA with shorter and less structured 5′ UTRs, like that of GAPDH, are predicted to be largely unaffected. These data suggest that targeting the 5′ cap‐binding domain of eIF4E may be a viable option to slow cancer cell growth and alter the malignant phenotype. © 2006 Wiley‐Liss, Inc.
Prediction of surface crown pillar stability using artificial neural networks
Authors: Tawadrous A. S. , Katsabanis P. D. 
Published: November 2006

AbstractA relatively novel technique, artificial neural networks (ANN), is used in predicting the stability of crown pillars left over large excavations. Data for the training and verification of the networks were obtained from the literature. Four artificial networks, based on two different architectures, were used. The networks used different numbers of input parameters to predict the stability or failure of crown pillars. Multi‐layer perceptron networks using mine type, dip of orebody, overburden thickness, pillar thickness, pillar length, stope height, backfill height, Rock Mass Rating (RMR) of the host rock and RMR of the orebody showed excellent performance in training and verification. Adding three more variables, namely pillar width, rock density and pillar thickness to width ratio, showed symptoms of over‐learning without degrading performance significantly. Radial basis function networks were capable of predicting crown pillar behaviour on the basis of few input functions. It was shown that mine type, dip and pillar thickness to width ratio can be used for a preliminary estimation of stability. Copyright © 2006 John Wiley & Sons, Ltd.
Upper bound limit analysis using simplex strain elements and second‐order cone programming
Authors: Makrodimopoulos A. , Martin C. M. 
Published: November 2006

AbstractIn geomechanics, limit analysis provides a useful method for assessing the capacity of structures such as footings and retaining walls, and the stability of slopes and excavations. This paper presents a finite element implementation of the kinematic (or upper bound) theorem that is novel in two main respects. First, it is shown that conventional linear strain elements (6‐node triangle, 10‐node tetrahedron) are suitable for obtaining strict upper bounds even in the case of cohesive‐frictional materials, provided that the element sides are straight (or the faces planar) such that the strain field varies as a simplex. This is important because until now, the only way to obtain rigorous upper bounds has been to use constant strain elements combined with a discontinuous displacement field. It is well known (and confirmed here) that the accuracy of the latter approach is highly dependent on the alignment of the discontinuities, such that it can perform poorly if an unstructured mesh is employed. Second, the optimization of the displacement field is formulated as a standard second‐order cone programming (SOCP) problem. Using a state‐of‐the‐art SOCP code developed by researchers in mathematical programming, very large example problems are solved with outstanding speed. The examples concern plane strain and the Mohr–Coulomb criterion, but the same approach can be used in 3D with the Drucker–Prager criterion, and can readily be extended to other yield criteria having a similar conic quadratic form. Copyright © 2006 John Wiley & Sons, Ltd.
Analysis of SMA composite laminates using a multiscale modelling technique
Authors: Marfia Sonia , Sacco Elio 
Published: November 2006

AbstractThe present work deals with the analysis of smart laminates, obtained as stacking sequence of fibre‐reinforced composite laminae and composite shape memory alloy (SMA) layers. The behaviour of composite SMA (CSMA) laminate is studied developing a full micro–macro approach. In fact, a non‐linear 4‐node mixed interpolation of tensorial components (MITC4) laminate finite element, based on the first‐order shear deformation theory, is developed. The SMA layer constitutive relationship is determined solving a non‐linear homogenization problem at each non‐linear iteration of each time step for each integration Gauss point. Some numerical applications are developed in order to investigate the influence of the CSMA on the buckling behaviour of plates and on the transversal displacement control of plates subjected to different loading conditions. Copyright © 2006 John Wiley & Sons, Ltd.
Analysis of plates stiffened by parallel beams
Authors: Sapountzakis E. J. , Mokos V. G. 
Published: November 2006

AbstractIn this paper a general solution for the analysis of plates stiffened by parallel beams subjected to an arbitrary loading is presented. According to the proposed model, the stiffening beams are isolated from the plate by sections in the lower outer surface of the plate, taking into account the arising tractions in all directions at the fictitious interfaces. The aforementioned integrated tractions result in the loading of the beams as well as the additional loading of the plate. Their distribution is established by applying continuity conditions in all directions at the interfaces. The analysis of both the plate and the beams is accomplished on their deformed shape taking into account second‐order effects. Six boundary value problems with respect to the plate transverse deflection, to the plate inplane displacement components, to the beam transverse deflections, to the beam axial deformation and to the beam non‐uniform angle of twist are formulated and solved using the analog equation method (AEM), a boundary element method (BEM)‐based method employing a boundary integral equation approach. The solution of the aforementioned plate and beam problems, which are non‐linearly coupled, is achieved using iterative numerical methods. The adopted model describes better the actual response of the plate beams system and permits the evaluation of the shear forces at the interfaces in both directions, the knowledge of which is very important in the design of prefabricated ribbed plates. The evaluated lateral deflections of the plate–beams system are found to exhibit considerable discrepancy from those of other models, which neglect inplane and axial forces and deformations. Copyright © 2006 John Wiley & Sons, Ltd.
Estimation of cable safety factors of suspension bridges using artificial neural network‐based inverse reliability method
Authors: Cheng Jin , Cai C. S. , Xiao Ru‐Cheng 
Published: November 2006

AbstractThe design of the main cables of suspension bridges is based on the verification of the rules defined by standard specifications, where cable safety factors are introduced to ensure safety. However, the current bridge design standards have been developed to ensure structural safety by defining a target reliability index. In other words, the structural reliability level is specified as a target to be satisfied by the designer. Thus, calibration of cable safety factors is needed to guarantee the specified reliability of main cables. This study proposes an efficient and accurate algorithm to solve the calibration problem of cable safety factors of suspension bridges. Uncertainties of the structure and load parameters are incorporated in the calculation model. The proposed algorithm integrates the concepts of the inverse reliability method, non‐linear finite element method, and artificial neural networks method. The accuracy and efficiency of this method with reference to an example long‐span suspension bridge are studied and numerical results have validated its superiority over the conventional deterministic method or inverse reliability method with Gimsing's simplified approach. Finally, some important parameters in the proposed method are also discussed. Copyright © 2006 John Wiley & Sons, Ltd.
Nano clay reinforced biodegradable plastics of PCL starch blends
Authors: Ikeo Yasuhiro , Aoki Kazuhiko , Kishi Hajime , Matsuda Satoshi , Murakami Atsushi 
Published: November 2006

AbstractOne of the conventional methods to develop biodegradable plastics at a reasonable cost is manufacturing the blend of expensive polycaprolactone (PCL) and lower‐priced starch. However, past studies have shown that the amount of starch blended with plastics is relatively small and the dynamic properties are not sufficiently improved. This study focuses on the improvement of physical properties of starch, including thermal plasticity, compatibility with PCL and dynamic properties. Starch was blended with glycerine and water to achieve thermal plasticity and improve compatibility with PCL. Addition of maleic anhydride to PCL improved compatibility, which resulted in improved dynamic properties. Addition of clay results in dispersed thermo plastic starch, which improves compatibility with PCL. In addition, it was clarified that addition of clay accelerates the positive effect of electron irradiation on the blend. Copyright © 2006 John Wiley & Sons, Ltd.
Pinch‐off syndrome in patients with sickle cell disease receiving erythrocytapheresis
Authors: Nuss Rachelle , Cole Laura , Le Tuan , Orsini Edmund , Harned Roger 
Published: November 2006

AbstractA 6‐year‐old female with homozygous sickle cell disease had a central venous access device (CVAD) placed to facilitate chronic erythrocytapheresis. Erythrocytapheresis was ineffective due to the rare pinch‐off syndrome causing communication between the dual lumen tubing. Awareness of and monitoring for the pinch‐off syndrome is indicated in people with sickle cell disease and a CVAD for chronic erythrocytapheresis. Pediatr Blood Cancer 2008;50:354–356. © 2006 Wiley‐Liss, Inc.
SRPK1: A cisplatin sensitive protein expressed in retinoblastoma
Authors: Krishnakumar Subramanian , Mohan Adithi , Kandalam Mallikarjuna , Ramkumar Hema L. , Venkatesan Nalini , Das Radha R. 
Published: November 2006

AbstractChemotherapy is an essential modality in the treatment of retinoblastoma (RB). Mammalian serine/arginine‐rich protein‐specific kinase 1 (SRPK1) is a cisplatin‐sensitivity‐related protein and its downregulation is known to be associated with decreased response to cisplatin and carboplatin. We investigated the expression of SRPK1 in 63 archival RB and correlated its expression with pathologic staging and exposure to chemotherapy. The majority of the RB (62/63) were advanced stage (Groups D and E) with intermediate to high risk of treatment failure according to the new international classification for intraocular RB and SRPK1 was reduced in 32/62 (51%) tumors. SRPK1 protein expression was reduced in (100%) 8/8 RB that had recurred in the orbit or had metastasized. SRPK1 protein expression is reduced in RB with advanced stage of presentation and this may add to drug resistance mechanisms in RB. Pediatr Blood Cancer 2008;50:402–406. © 2006 Wiley‐Liss, Inc.
Benzophenone‐functionalized, starlike polystyrenes as organic supports for a tridentate bis(imino)pyridinyliron/trimethylaluminum catalytic system for ethylene polymerization
Authors: Bouilhac Cécile , Cramail Henri , Cloutet Eric , Deffieux Alain , Taton Daniel 
Published: November 2006

AbstractStarlike polystyrenes composed of a microgel core and arms terminated with benzophenone groups were used as organic supports for a tridentate bis(imino)pyridinyliron catalyst for ethylene polymerization in the presence of trimethylaluminum as a cocatalyst. The microgels were synthesized by the atom transfer radical polymerization of styrene initiated by 4‐(1‐bromoethyl)‐benzophenone, with divinylbenzene as the crosslinker. The bromine polystyrene chain ends prevented the ethylene polymerization reaction and had to be removed. This was readily achieved with Cu0 together with dodecanethiol as a transfer agent. When used as supports in the presence of trimethylaluminum and 2,6‐bis[1‐2,6(diisopropylphenyl)imino]ethylpyridynyl iron, these bromine‐free, functionalized polystyrene stars enabled the production of polyethylene beads of a spherical morphology and high bulk density with a catalytic activity similar to that under homogeneous reaction conditions. Moreover, the molar mass distribution of the polyethylene was narrow, suggesting limited transfer to trimethylaluminum. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 6997–7007, 2006
Ellipsometry as a probe of crystallization kinetics in thin diblock copolymer films
Authors: Carvalho J. L. , Massa M. V. , Dalnoki‐Veress K. 
Published: November 2006

AbstractWe present results on the use of ellipsometry as a novel probe for the crystallization kinetics in thin films of a diblock copolymer. Ellipsometry makes use of the change in polarization induced upon the reflection of light from a film‐covered substrate to enable the calculation of the refractive index and thickness of the film. The information obtained with these measurements can be compared with information from differential scanning calorimetry, with the additional advantages that small sample volumes and slow cooling rates can be employed and that expansion coefficients can be determined. By studying the temperature dependence of these quantities, we are able to measure the crystallization kinetics within very small volumes (∼10−10 L) of a poly(butadiene‐b‐ethylene oxide) diblock copolymer. Through a comparison of two different poly (ethylene oxide) block lengths, we demonstrate a reduction in both the crystallization and melting temperatures as the domain volume is reduced. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 3448–3452, 2006