bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sensitivity of YBa2Cu3O7 thick films to gamma rays
Authors: Albiss B. A. , Al‐Akhras M. A. 
Published: November 2006

AbstractSuperconducting YBa2Cu3O7 (YBCO) thick films have been prepared using the screen printing method. Effects of gamma irradiation on their structure and transport properties have been investigated up to a gamma dose of 50 MR. A considerable decrease in the intensities of the major diffraction peaks of the XRD pattern was observed due to gamma irradiation. A gradual increase in the normal state resistance, with a gradual increase in the slope of the resistance‐temperature (R‐T) curves was observed with increasing gamma doses. However, slight decrease in the transition temperature has been observed. The Voltage‐current (V‐I) data were fitted to the power law V ∼ Iβ in which the power exponent β was found to increase gradually with gamma dose. The sensitivity of the R‐T and V‐I curves to gamma rays where precisely estimated and from which the regions of linear response were deduced. The possibility of using YBCO thick film as a candidate device for gamma rays sensing was presented. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Enhancement of solder properties of Sn‐9Zn lead‐free solder alloy
Authors: Kamal M. , Gouda E. S. 
Published: November 2006

AbstractThe eutectic alloy Sn‐9Zn was considered as a potential alternative to lead‐tin solder alloys when compared with other solders. In this paper, ternary, quaternary and penternary additions of the elements Bi, Cu and In were added to the eutectic alloy as a trial to improve its properties. The results showed that, the penternary alloy has properties superior to those of the binary, ternary and quaternary alloys. The alloy of composition Sn‐9Zn‐1Bi‐2Cu‐2In has the most suitable properties as a candidate alloy for lead‐free solder. It has a lower melting point, 186°C, which is very close to that of Sn‐37Pb solder, a lower value of electrical resistivity, 16.5 μΩ.cm, compared with that of Sn‐37Pb (17 μΩ.cm), higher value of the Young's modulus, 47 GPa, compared with 45 GPa of Sn‐37Pb and a higher value of the Vickers hardness, 191 MPa, compared with 129 MPa of Sn‐37Pb eutectic alloy. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Crystal and molecular structure of 1‐allyl‐5‐(4‐methylbenzoyl)‐4‐(4‐methylphenyl)pyrimidine‐2(1H)‐thione
Authors: Yıldırım İ. , Koca İ. , Dinçer M. , Özdemir N. , Andaç Ö. 
Published: November 2006

AbstractThe crystal structure of 1‐allyl‐5‐(4‐methylbenzoyl)‐4‐(4‐methylphenyl)pyrimidine‐2(1H)‐thione (C22H20N2OS) has been determined from three dimensional single crystal X‐ray diffraction data. The title compound crystallizes in the monoclinic space group P 21/c, with a = 10.6674(13), b = 10.1077(7), c = 17.9467(19) Å, β = 98.460(9)°, V = 1914.0(3) Å3, Dcalc = 1.251 g cm–3, Z = 4. In the title compound, the allyl group shows positional disorder. Molecules are linked by C‐H···O, C‐H···N and C‐H···S intermolecular interactions forming two‐dimensional network. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A General and Facile One‐Step Synthesis of Imido–Titanium(IV) Complexes: Application to the Synthesis of Compounds Containing Functionalized or Chiral Imido Ligands and Bimetallic Diimido Architectures (Eur. J. Inorg. Chem. 22/2006)
Authors: Lorber Christian , Choukroun Robert , Vendier Laure 
Published: November 2006

AbstractThe cover picture shows some various examples ofterminal imido–titanium complexes of the general formula Ti(=NR)Cl2(NHMe2)2 that are accessible through the reported one‐pot reaction of Ti(NMe2)4 with a primary amine RNH2 in the presence of excess chlorotrimethylsilane. This procedure appears to be general to the generation of a wide range of imido groups: alkyl‐, silyl‐, and arylimido groups, as well as functional organoimido, chiral imido, and diimido ligands. Ti(=NR)Cl2(NHMe2)2 complexes are of particular interest as organometallic synthons and for further applications in the field of homogeneous catalysis and materials science. The background photo of the famous palm tree vault of the Jacobins church (Toulouse, France, founded in the 13th–14th centuries) symbolizes the diversity of the compounds – arranged in arc around the palm tree vault – that can be prepared by using our promising synthetic strategy, and provides a solid foundation – the pillar – for attractive applications. Details are discussed in the article by C. Lorber et al. on p. 4503 ff. The authors acknowledge Christian Bergounhou (LCC Toulouse) for the Palm Tree photograph.
Aging of transformer insulating materials under selective conditions
Authors: Fofana I. , Borsi H. , Gockenbach E. , Farzaneh M. 
Published: November 2006

AbstractIn today's economic climate, it is important to know the condition, by means of suitable diagnostic tests, of the oil impregnated paper usable as primary insulation in equipment such as transformers, switchgear, bushings, cables, and their accessories. The aim of this paper is regarded as a main task to study the parameters that mostly influence the ageing process of oil/paper insulation used in transformers with preset moisture levels. A comparison is made between the performances of cellulose and Aramid papers. It is shown that Aramid paper is much less sensitive to water than cellulose paper. However, the addition of air (oxygen), via acid formation and oxidation in the oil, has a direct influence on the increase of the loss factor for both papers. The catalysts, that represent the metallic components in the transformer, accelerate the ageing process of the cellulose papers, while no influence on the ageing process of Aramid was observed. Oil ageing without a solid partner is insignificantly influenced by water, but accelerated by air‐oxygen, via the moisture and acid formation, and oxidation processes. A direct influence on the increase of the loss factor and the decrease of electric strength particularly at low temperatures is to be noted. Copyright © 2006 John Wiley & Sons, Ltd.
Analysis of load transfer on radial distribution systems with tie lines
Authors: Lee Chien‐Hsing , Huang Chi‐Ming 
Published: November 2006

AbstractThis paper analyzes four types of load transfer in the radial distribution system with tie lines of Taiwan power company (TPC). Type I is the two feeders tied and were fed by the same transformer located in the same secondary substation. Type II is the two feeders tied and were fed by two different transformers located in the same secondary substation. Type III is the two feeders tied and were fed by two different transformers located in different secondary substations. Type IV is the two feeders tied and were fed by two different transformers, one is located in a distribution substation and the other is located in a secondary substation. The test results are recorded and summarized to determine the effective scheme of load transfer without power interruptions. As a result, Type I is the most simple method to eliminate customers' interruption during load transfer. Copyright © 2006 John Wiley & Sons, Ltd.
Using vorticity to define conditions at multiple open boundaries for simulating flow in a simplified vortex settling basin
Authors: Ziaei A. N. , McDonough J. M. , Emdad H. , Keshavarzi A. R. 
Published: November 2006

AbstractIn this paper a method is developed to define multiple open boundary (OB) conditions in a simplified vortex settling basin (VSB). In this method, the normal component of the momentum equation is solved at the OBs, and tangential components of vorticity are calculated by solving vorticity transport equations only at the OBs. Then the tangential vorticity components are used to construct Neumann boundary conditions for tangential velocity components. Pressure is set to its ambient value, and the divergence‐free condition is satisfied at these boundaries by employing the divergence as the Neumann condition for the normal‐direction momentum equation. The 3‐D incompressible Navier–Stokes equations in a primitive‐variable form are solved using the SIMPLE algorithm. Grid‐function convergence tests are utilized to verify the numerical results. The complicated laminar flow structure in the VSB is investigated, and preliminary assessment of two popular turbulence models, k–ε and k–ω, is conducted. Copyright © 2006 John Wiley & Sons, Ltd.
Reducing vascular variability of fMRI data across aging populations using a breathholding task
Authors: Handwerker Daniel A. , Gazzaley Adam , Inglis Ben A. , D'Esposito Mark 
Published: November 2006

AbstractThe magnitude and shape of blood oxygen level‐dependent (BOLD) responses in functional MRI (fMRI) studies vary across brain regions, subjects, and populations. This variability may be secondary to neural activity or vasculature differences, thus complicating interpretations of BOLD signal changes in fMRI experiments. We compare the BOLD responses to neural activity and a vascular challenge and test a method to dissociate these influences in 26 younger subjects (ages 18–36) and 24 older subjects (ages 51–78). Each subject performed a visuomotor saccade task (a vascular response to neural activity) and a breathholding task (vascular dilation induced by hypercapnia) during separate runs in the same scanning session. For the saccade task, signal magnitude showed a significant decrease with aging in FEF, SEF, and V1, and a delayed time‐to‐peak with aging in V1. The signal magnitudes from the saccade and hypercapnia tasks showed significant linear regressions within subjects and across individuals and populations. These two tasks had weaker, but sometimes significant linear regressions for time‐to‐peak and coherence phase measures. The significant magnitude decrease with aging in V1 remained after dividing the saccade task magnitude by the hypercapnia task magnitude, implying that the signal decrease is neural in origin. These findings may lead to a method to identify vascular reactivity‐induced differences in the BOLD response across populations and the development of methods to account for the influence of these vasculature differences in a simple, noninvasive manner. Hum Brain Mapp 2006. © 2006 Wiley‐Liss, Inc.
Validity and power in hemodynamic response modeling: A comparison study and a new approach
Authors: Lindquist Martin A. , Wager Tor D. 
Published: November 2006

AbstractOne of the advantages of event‐related functional MRI (fMRI) is that it permits estimation of the shape of the hemodynamic response function (HRF) elicited by cognitive events. Although studies to date have focused almost exclusively on the magnitude of evoked HRFs across different tasks, there is growing interest in testing other statistics, such as the time‐to‐peak and duration of activation as well. Although there are many ways to estimate such parameters, we suggest three criteria for optimal estimation: 1) the relationship between parameter estimates and neural activity must be as transparent as possible; 2) parameter estimates should be independent of one another, so that true differences among conditions in one parameter (e.g., hemodynamic response delay) are not confused for apparent differences in other parameters (e.g., magnitude); and 3) statistical power should be maximized. In this work, we introduce a new modeling technique, based on the superposition of three inverse logit functions (IL), designed to achieve these criteria. In simulations based on real fMRI data, we compare the IL model with several other popular methods, including smooth finite impulse response (FIR) models, the canonical HRF with derivatives, nonlinear fits using a canonical HRF, and a standard canonical model. The IL model achieves the best overall balance between parameter interpretability and power. The FIR model was the next‐best choice, with gains in power at some cost to parameter independence. We provide software implementing the IL model. Hum Brain Mapp 2006. © 2006 Wiley‐Liss, Inc.
Effect of the number of response alternatives on brain activity in response selection
Authors: Woo Sung‐Ho , Lee Kyoung‐Min 
Published: November 2006

AbstractIt is well‐known in motor control literature that a response time (RT) increases as a logarithmic function of the number of response alternatives (NA) (Hick's law). In this study, we identified neural correlates for this relationship using event‐related functional MRI and a choice finger‐movement task. Behaviorally, average RTs of all subjects increased as a logarithmic function of the NA in accordance with the law. From a voxel‐wise search for brain areas where the activity was correlated with NA and thence the RT, a positive correlation was found at the posterior cingulate and left superior frontal gyri, whereas a negative correlation was observed at areas in bilateral inferior parietal lobules. This differential modulation by the task context, namely, the NA available for a choice response with identical stimulus and response, indicates that these regions are involved in various aspects of response selection, intentional retrieval of motor program, or spatial expectancy. Hum Brain Mapp 2006. © 2006 Wiley‐Liss, Inc.
Kinin B1 and B2 receptors are overexpressed in the hippocampus of humans with temporal lobe epilepsy
Authors: Perosa Sandra Regina , Argañaraz Gustavo Adolfo , Goto Eduardo Massatoshi , Costa Luciana Gilbert Pessoa , Konno Ana Carla , Varella Pedro Paulo Vasconcellos , Santiago Joselita Ferreira Carvalho , Pesquero João Bosco , Canzian Mauro , Amado Debora , Yacubian Elza Marcia , Carrete Henrique , Centeno Ricardo Silva , Cavalheiro Esper Abrão , Silva Jose Antonio , Mazzacoratti Maria da Graça Naffah 
Published: November 2006

AbstractMolecular biology tools have been employed to investigate the participation of peptides in human temporal lobe epilepsy (TLE). Active polypeptides and their receptors have been related to several brain processes, such as inflammation, apoptosis, brain development, K+ and Ca2+ channels' activation, cellular growth, and induction of neuronal differentiation. Previous works have shown a neuroprotector effect for kinin B2 receptor and a deleterious, pro‐epileptogenic action for kinin B1 receptor in animal models of TLE. The present work was delineated to analyze the kinin B1 and B2 receptors expression in the hippocampus of patients presenting refractory mesial TLE. The hippocampi were removed during the patients surgery in a procedure used for seizure control and compared with tissues obtained after autopsy. Nissl staining was performed to study the tissue morphology and immunohistochemistry, and Western blot was used to compare the distribution and levels of both receptors in the hippocampus. In addition, real time PCR was employed to analyze the gene expression of these receptors. Nissl staining showed sclerotic hippocampi with hilar, granular, and pyramidal cell loss in TLE patients. Immunohistochemistry and Western blot analyses showed increased expression of kinin B1 and B2 receptors but the real‐time PCR data demonstrated increased mRNA level only for kinin B2 receptors, when compared with controls. These data show for the first time a relationship between human TLE and the kallikrein–kinin system, confirming ours previous results, obtained from experimental models of epilepsy. © 2006 Wiley‐Liss, Inc.
Transforming growth factor‐β2 modulates synaptic efficacy and plasticity and induces phosphorylation of CREB in hippocampal neurons
Authors: Fukushima Teruyuki , Liu Rong‐Yu , Byrne John H. 
Published: November 2006

AbstractTransforming growth factor‐βs (TGF‐βs) are widely expressed and play roles as multifunctional growth factors and regulators of key events in development, disease, and repair. However, it is not known whether TGF‐βs affect the plasticity of hippocampal neurons. As a first step to address this issue, we examined whether TGF‐β2 modulated the electrophysiological and biochemical properties of cultured hippocampal neurons. We found that prolonged 24 h treatment with TGF‐β2 induced facilitation of evoked postsynaptic currents (ePSCs). This facilitation was associated with a decrease in short‐term synaptic depression of ePSCs and increases in both the amplitude and frequency of spontaneous miniature postsynaptic currents (mPSCs). The long‐term changes of ePSCs and mPSCs may be associated with cAMP response element‐binding protein (CREB), which has been previously implicated in long‐term potentiation. Immunofluorescence techniques and Western blot analysis both revealed that TGF‐β2 enhanced the phosphorylation of CREB. Together, these results suggest that TGF‐β2 may play a role in the cascade of events underlying long‐term synaptic facilitation in hippocampus, and that CREB may be an important mediator of these effects. © 2006 Wiley‐Liss, Inc.
Functional divergence after gene duplication and sequence–structure relationship: a case study of G‐protein alpha subunits
Authors: Zheng Ying , Xu Dongping , Gu Xun 
Published: November 2006

AbstractIn this article, we use animal G‐protein alpha subunit family as an example to illustrate a comprehensive analytical pipeline for detecting different types of functional divergence of protein families, which is phylogeny‐dependent, combined with ancestral sequence inference and available protein structure information. In particular, we focus on (i) Type‐I functional divergence, or site‐specific rate shift, as typically exemplified by amino acid residue highly conserved in a subset of homologous genes but highly variable in a different subset of homologous genes, and (ii) Type‐II functional divergence, or the shift of cluster‐specific amino acid property, as exemplified by a radical shift of amino acid property between duplicate genes, which is otherwise evolutionally conserved. We utilized the software DIVERGE2 to carry out these analyses. In the case of G‐protein alpha subunit gene family, we have predicted amino acid residues that are related to either Type‐I or Type‐II functional divergence. The inferred ancestral sequences for these sites are helpful to explore the trends of functional divergence. Finally, these predicted residues are mapped to the protein structures to test whether these residues may have 3D structure or solvent accessibility preference. J. Exp. Zool. (Mol. Dev. Evol.) 306B, 2006. © 2006 Wiley‐Liss, Inc.
Cerebral vascular response to hypercapnia: Determination with perfusion MRI at 1.5 and 3.0 Tesla using a pulsed arterial spin labeling technique
Authors: Nöth Ulrike , Meadows Guy E. , Kotajima Futoshi , Deichmann Ralf , Corfield Douglas R. , Turner Robert 
Published: November 2006

AbstractPurposeTo compare the quantification of cerebral blood flow (CBF) at 1.5 and 3.0 Tesla, under normo‐ and hypercapnia, and to determine the cerebral vascular response (CVR) of gray matter (GM) to hypercapnia, a pulsed arterial spin labeling technique was used. Additionally, to improve GM CBF quantification a high‐resolution GM‐mask was applied.Materials and MethodsCBF was determined with the QUIPSS II with thin slice TI1 periodic saturation (Q2TIPS) sequence at 1.5 and 3.0 Tesla in the same group of eight subjects, both under normocapnia and hypercapnia. Absolute GM‐CBF maps were calculated using a GM‐mask obtained from a high‐resolution structural scan by segmentation. The CVR to hypercapnia was derived from the quantitative GM‐CBF maps.ResultsFor both field strengths, the GM‐CBF was significantly higher under hypercapnia compared to normocapnia. For both conditions, there was no significant difference of GM‐CBF for 1.5 and 3.0 Tesla; the same applies to the CVR, which was 4.3 and 4.5%/mmHg at 1.5 and 3.0 Tesla, respectively.ConclusionThe method presented allows for the quantification of CBF and CVR in GM at the common clinical field strengths of 1.5 and 3.0 Tesla and could therefore be a useful tool to study these parameters under physiological and pathophysiological conditions. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Multiple organizational identification levels and the impact of perceived external prestige and communication climate
Authors: Bartels Jos , Pruyn Ad , de Jong Menno , Joustra Inge 
Published: November 2006

AbstractEarlier studies have shown that perceived external prestige and communication climate influence organizational identification. In this paper we present the results of a study of the influence of communication climate and perceived external prestige on organizational identification at various organizational levels of a regional police organization. In total, 314 respondents filled out a questionnaire on communication climate, perceived external prestige and organizational identification. The results of this study show that communication climate has the strongest link with employee identification when it concerns the identification with the daily work group and a weaker one with the organization as a whole. It also appears that perceived external prestige has a stronger influence on the identification with the organization as a whole than on the identification at the more concrete organizational levels (such as department or work group). This research offers reasons to presuppose that organizational identification and communication climate are multiple constructs. If management wishes to influence organizational identification through a bottom‐up process, it is wise to pay particular attention to the communication climate in the work groups. Influencing organizational identification with the organization as a whole is better conducted through perceived external prestige. Copyright © 2006 John Wiley & Sons, Ltd.
Functionally perturbed stochastic differential equations
Authors: Jovanović Miljana , Janković Svetlana 
Published: November 2006

AbstractThis paper is devoted to the large class of stochastic differential equations of the Ito type whose coefficients are functionally perturbed and depend on a small parameter. The solution of a such equation is compared with the solution of the corresponding unperturbed equation, in the (2m)‐th moment sense, on finite intervals or on intervals whose length tends to infinity as small parameter tends to zero. Some numerical estimations of these intervals with respect to the parameter are also given. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On the absolutely continuous spectrum of the Laplace–Beltrami operator acting on p ‐forms for a class of warped product metrics
Authors: Antoci Francesca 
Published: November 2006

AbstractWe explicitely compute the absolutely continuous spectrum of the Laplace–Beltrami operator for p ‐forms for the class of warped product metrics dσ 2 = y 2a dy 2 + y 2b dθ 2, where y is a boundary defining function on the unit ball B (0, 1) in ℝN . (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Another characterization of the Hardy space with non doubling measures
Authors: Hu Guoen , Liang Shuang 
Published: November 2006

AbstractLet μ be a Radon measure on ℝd which may be non doubling, and let H 1(μ) be the Hardy space associated with μ introduced by Tolsa. In this paper, a new atomic characterization of H 1(μ) is established. Some applications of this characterization are also given. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)