bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analysis of the effects of Nyquist pulse‐shaping on the performance of OFDM systems with carrier frequency offset
Authors: Tan Peng , Beaulieu Norman C. 
Published: July 2008

AbstractAn exact method for calculating the bit error rate (BER) of an uncoded orthogonal frequency‐division multiplexing (OFDM) system with transmitter Nyquist pulse‐shaping over AWGN channels in the presence of frequency offset is derived. This method represents a unified way to calculate the BER of this system with different one‐ and two‐dimensional subcarrier modulation formats. The precise BER expressions are obtained using a characteristic function method.The effects of several widely referenced Nyquist pulse‐shapings, including the Franks pulse, the raised‐cosine pulse, the ‘better than’ raised‐cosine (BTRC) pulse, the second‐order continuous window (SOCW), the double‐jump pulse and the polynomial pulse on intercarrier interference (ICI) reduction and BER improvement of the system with carrier frequency offset are examined in the AWGN channel. The dependence of the BER on the roll‐off factor of the pulse employed for a specific system in the presence of frequency offset is investigated. Analysis and numerical results show that the Franks pulse exhibits the best performance among the Nyquist pulses considered in most cases. Copyright © 2008 John Wiley & Sons, Ltd.
Local Heaviside‐weighted LRPIM meshless method and its application to two‐dimensional potential flows
Authors: Saeedpanah Iraj , Jabbari E. 
Published: July 2008

AbstractIn this paper, the local radial point interpolation meshless method (LRPIM) is used for the analysis of two‐dimensional potential flows, based on a local‐weighted residual method with the Heaviside step function as the weighting function over a local subdomain. Trial functions are constructed using radial basis functions. The present method is a truly meshless method based only on a number of randomly located nodes. Integration over the subdomains requires only a simple integration cell to obtain the solution. No element matrix assembly is required and no special treatment is needed to impose the essential boundary conditions. The novelty of the paper is the use of a local Heaviside weight function in the LRPIM, which does not need local domain integration and integrations only on the boundary of the local domains are needed. Effects of the sizes of local subdomain and interpolation domain on the performance of the present method are investigated. The behavior of shape parameters of multiquadrics has been systematically studied. Two numerical tests in groundwater and fluid flows are presented and compared with closed‐form solutions and finite element method. The results show that the use of a local Heaviside weight function in the LRPIM is highly accurate and possesses no numerical difficulties. Copyright © 2008 John Wiley & Sons, Ltd.
Numerical simulation of liquid crystalline polymer flow into two‐dimensional thin cavity moulds
Authors: Sun Jianye 
Published: July 2008

AbstractIn this paper, flows of liquid crystalline polymers into two‐dimensional thin cavity moulds are simulated. The flows are modelled by Ericksen–Leslie equations of motion in the high viscosity limit. An elliptic pressure equation is derived under Hele–Shaw approximations, and the non‐isothermal natures of the flow are modelled. The equations are solved using the finite‐difference technique. A new boundary‐mapping technique is developed in this study to solve the difficulty in the finite‐difference treatment of arbitrarily shaped boundaries, which possess no natural coordinate system. This new method avoids the difficult mesh control in the body‐fitted mapping process and makes the mapping process easy to implement. It can also solve the problems caused by the uneven distribution of grid nodes in the traditional body‐fitted mapping technique. Copyright © 2008 John Wiley & Sons, Ltd.
Impact of mass lumping on gravity and Rossby waves in 2D finite‐element shallow‐water models
Authors: Le Roux D. Y. , Hanert E. , Rostand V. , Pouliot B. 
Published: July 2008

AbstractThe goal of this study is to evaluate the effect of mass lumping on the dispersion properties of four finite‐element velocity/surface‐elevation pairs that are used to approximate the linear shallow‐water equations. For each pair, the dispersion relation, obtained using the mass lumping technique, is computed and analysed for both gravity and Rossby waves. The dispersion relations are compared with those obtained for the consistent schemes (without lumping) and the continuous case. The P0−P1, RT0 and P−P1 pairs are shown to preserve good dispersive properties when the mass matrix is lumped. Test problems to simulate fast gravity and slow Rossby waves are in good agreement with the analytical results. Copyright © 2008 John Wiley & Sons, Ltd.
Implicit–explicit finite‐difference lattice Boltzmann method with viscid compressible model for gas oscillating patterns in a resonator
Authors: Wang Yong , He Yaling , Huang Jing , Li Qing 
Published: July 2008

AbstractDifficulties for the conventional computational fluid dynamics and the standard lattice Boltzmann method (LBM) to study the gas oscillating patterns in a resonator have been discussed. In light of the recent progresses in the LBM world, we are now able to deal with the compressibility and non‐linear shock wave effects in the resonator. A lattice Boltzmann model for viscid compressible flows is introduced firstly. Then, the Boltzmann equation with the Bhatnagar–Gross–Krook approximation is solved by the finite‐difference method with a third‐order implicit–explicit (IMEX) Runge–Kutta scheme for time discretization, and a fifth‐order weighted essentially non‐oscillatory (WENO) scheme for space discretization. Numerical results obtained in this study agree quantitatively with both experimental data available and those using conventional numerical methods. Moreover, with the IMEX finite‐difference LBM (FDLBM), the computational convergence rate can be significantly improved compared with the previous FDLBM and standard LBM. This study can also be applied for simulating some more complex phenomena in a thermoacoustics engine. Copyright © 2008 John Wiley & Sons, Ltd.
Three‐dimensional numerical simulation of compound meandering open channel flow by the Reynolds stress model
Authors: Jing H. , Guo Y. , Li C. , Zhang J. 
Published: July 2008

AbstractTurbulent flow in a compound meandering open channel with seminatural cross sections is one of the most complicated turbulent flows as the flow pattern is influenced by the combined action of various forces, such as centrifugal force, pressure, and shear stresses. In this paper, a three‐dimensional (3D) Reynolds stress model (RSM) is adopted to simulate the compound meandering channel flows. Governing equations of the flow are solved numerically with finite‐volume method. The velocity fields, wall shear stresses, and Reynolds stresses are calculated for a range of input conditions. Good agreement between the simulated results and measurements indicates that RSM can successfully predict the complicated flow phenomenon. Copyright © 2008 John Wiley & Sons, Ltd.
A semi‐implicit finite volume implementation of the CSF method for treating surface tension in interfacial flows
Authors: Raessi M. , Bussmann M. , Mostaghimi J. 
Published: July 2008

AbstractWe present an implementation of Hysing's (Int. J. Numer. Meth. Fluids 2006; 51:659–672) semi‐implicit method for treating surface tension, for finite volume models of interfacial flows. Using this method, the surface tension timestep restriction, which is often very stringent, can be exceeded by at least a factor of 5 without destabilizing the solution. The surface tension force in this method consists of an explicit part, which is the regular continuum surface force, and an implicit part which represents the diffusion of velocities induced by surface tension on fluids interfaces. The surface tension force is applied to the velocity field by solving a system of equations iteratively. Since the equations are solved only near interfaces, the computational time spent on the iterative procedure is insignificant. Copyright © 2008 John Wiley & Sons, Ltd.
Novel V600E BRAF mutations in imatinib‐naive and imatinib‐resistant gastrointestinal stromal tumors
Authors: Agaram Narasimhan P. , Wong Grace C. , Guo Tianhua , Maki Robert G. , Singer Samuel , DeMatteo Ronald P. , Besmer Peter , Antonescu Cristina R. 
Published: July 2008

AbstractBRAF and NRAS are commonly mutated in cancer and represent the most frequent genetic events in malignant melanoma. More recently, a subset of melanomas was shown to overexpress KIT and harbor KIT mutations. Although most gastrointestinal stromal tumors (GISTs) exhibit activating mutations in either KIT or PDGFRA, about 10% of the cases lack mutations in these genes. It is our hypothesis following the melanoma model that mutations in BRAF or NRAS may play a role in wild‐type GIST pathogenesis. Alterations in RAS/MEK/ERK pathway may also be involved in development of imatinib resistance in GIST, particularly in tumors lacking secondary KIT or PDGFRA mutations. Imatinib‐naive wild‐type GISTs from 61 patients, including 15 children and 28 imatinib‐resistant tumors without secondary KIT mutations were analyzed. Screening for hot spots mutations in BRAF (exons 11 and 15) and NRAS (exons 2 and 3) was performed. A BRAF exon 15 V600E was identified in 3 of 61 GIST patients, who shared similar clinical features, being 49‐ to 55‐years‐old females and having their tumors located in the small bowel. The tumors were strongly KIT immunoreactive and had a high risk of malignancy. An identical V600E BRAF mutation was also identified in one of 28 imatinib resistant GIST lacking a defined mechanism of drug resistance. In conclusion, we identified a primary BRAF V600E mutations in 7% of adult GIST patients, lacking KIT/PDGFRA mutations. The BRAF‐mutated GISTs show predilection for small bowel location and high risk of malignancy. A secondary V600E BRAF mutation could represent an alternative mechanism of imatinib resistance. Kinase inhibitors targeting BRAF may be effective therapeutic options in this molecular GIST subset. © 2008 Wiley‐Liss, Inc.
Multipoint lods provide reliable linkage evidence despite unknown limiting distribution: type I error probabilities decrease with sample size for multipoint lods and mods
Authors: Hodge Susan E. , Rodriguez‐Murillo Laura , Strug Lisa J. , Greenberg David A. 
Published: July 2008

AbstractWe investigate the behavior of type I error rates in model‐based multipoint (MP) linkage analysis, as a function of sample size (N). We consider both MP lods (i.e., MP linkage analysis that uses the correct genetic model) and MP mods (maximizing MP lods over 18 dominant and recessive models). Following Xing and Elston (2006Genet. Epidemiol, 30: 447–458), we first consider MP linkage analysis limited to a single position; then we enlarge the scope and maximize the lods and mods over a span of positions. In all situations we examined,type I error rates decrease with increasing sample size, apparently approaching zero. We show: (a) For MP lods analyzed only at a single position, well‐known statistical theory predicts that type I error rates approach zero. (b) For MP lods and mods maximized over position, this result has a different explanation, related to the fact that one maximizes the scores over only a finite portion of the parameter range. The implications of these findings may be far‐reaching: Although it is widely accepted that fixed nominal critical values for MP lods and mods are not known, this study shows that whatever the nominal error rates are, the actual error rates appear to decrease with increasing sample size. Moreover, the actual (observed) type I error rate may be quite small for any given study. We conclude that MP lod and mod scores provide reliable linkage evidence for complex diseases, despite the unknown limiting distributions of these MP scores.Genet. Epidemiol. 2008. © 2008 Wiley‐Liss, Inc.
A partial least‐square approach for modeling gene‐gene and gene‐environment interactions when multiple markers are genotyped
Authors: Wang Tao , Ho Gloria , Ye Kenny , Strickler Howard , Elston Robert C. 
Published: July 2008

AbstractGenetic association studies achieve an unprecedented level of resolution in mapping disease genes by genotyping dense single nucleotype polymorphisms (SNPs) in a gene region. Meanwhile, these studies require new powerful statistical tools that can optimally handle a large amount of information provided by genotype data. A question that arises is how to model interactions between two genes. Simply modeling all possible interactions between the SNPs in two gene regions is not desirable because a greatly increased number of degrees of freedom can be involved in the test statistic. We introduce an approach to reduce the genotype dimension in modeling interactions. The genotype compression of this approach is built upon the information on both the trait and the cross‐locus gametic disequilibrium between SNPs in two interacting genes, in such a way as to parsimoniously model the interactions without loss of useful information in the process of dimension reduction. As a result, it improves power to detect association in the presence of gene‐gene interactions. This approach can be similarly applied for modeling gene‐environment interactions. We compare this method with other approaches, the corresponding test without modeling any interaction, that based on a saturated interaction model, that based on principal component analysis, and that based on Tukey's one‐degree‐of‐freedom model. Our simulations suggest that this new approach has superior power to that of the other methods. In an application to endometrial cancer case‐control data from the Women's Health Initiative, this approach detected AKT1 and AKT2 as being significantly associated with endometrial cancer susceptibility by taking into account their interactions with body mass index. Genet. Epidemiol. 2008. © 2008 Wiley‐Liss, Inc.
Age of the peel sandstone group, isle of man
Authors: Crowley Stephen F. , Higgs Kenneth T. , Piper John D.A. , Morrissey Lance B. 
Published: July 2008

AbstractAn Early Devonian age for the continental, red‐bed succession of the Peel Sandstone Group can be defined on the basis of: (1) a derived marine fauna of late Wenlock (Homerian) age, (2) a Scoyenia ichnofacies assemblage (including Beaconites and Diplichnites) characteristic of latest Silurian to Early Devonian (Lower Old Red Sandstone magnafacies) sediments in the British Isles, (3) a microflora of late Lochkovian to Pragian age, (4) a detrital palaeomagnetic remanence that pre‐dates local, Acadian palaeomagnetic directions and coincides with a prominent, southerly, Late Silurian to Early Devonian excursion in the local apparent polar wander path, and (5) a mid‐Devonian palaeomagnetic remanence that overprints (?)Acadian, thrust‐related folding. Data presented in this study confirm previous suggestions (Allen and Crowley 1983) that the Peel Sandstone Group represents a rare example of Early Devonian sedimentation preserved on the northern margin of the former Eastern Avalonia microcontinent. Potential correlations and linkages with other Lower Old Red Sandstone successions exposed in the Anglo‐Welsh Basin are developed and discussed. Copyright © 2008 John Wiley & Sons, Ltd.
Aggregate sources and supplies in Jamaica
Authors: Scott Peter W. , Harrison David J. 
Published: July 2008

AbstractAggregate resources in Jamaica are sand and gravel found in active river systems, and limestone. Other rocks in Cretaceous inliers and elsewhere are generally too weathered at the surface or too remote from centres of population to be considered suitable as significant sources of aggregates. Sand and gravel generally supplies the south of the country with limestone production and markets being concentrated along the northern coastal areas. Limestone aggregates are produced by ripping and crushing, blasting being uncommon. Sand and gravel are often simply processed using a single screen, although fixed crushing and screening plant are used in some operations. The aggregate industry operates inefficiently, generally utilizing old plant, although an economic assessment shows it to be very profitable. Substitution of sand and gravel by limestone would help mitigate the negative environmental impact of extraction of aggregates from active river systems, but would considerably distort the supply of aggregates throughout the country. Copyright © 2008 John Wiley & Sons, Ltd.
Confocal imaging and tracking of the exocytotic routes for D‐serine‐mediated gliotransmission
Authors: Martineau Magalie , Galli Thierry , Baux Gérard , Mothet Jean‐Pierre 
Published: July 2008

AbstractD‐Serine is an astrocyte‐derived regulator for N‐methyl‐D‐aspartate receptors, but the intracellular routes of its trafficking are still largely unknown. Here, we combined confocal microscopy with colocalization quantification to track the astrocytic organelles that store D‐serine. We report that D‐serine colocalizes with the transfected eGFP‐synaptobrevin/VAMP2 and eGFP‐cellubrevin/VAMP3, two v‐SNAREs of the regulated secretory pathway. No significant colocalization was found with markers of the endosomal sorting and recycling system: EEA1, eGFP‐endobrevin/VAMP8, eGFP‐TI‐VAMP/VAMP7, LAMP1, and CD63. Blockade of vesicular budding with colchicine shows that secretory vesicles import D‐serine downstream to the Golgi apparatus. Finally, treatment of astrocytes with the Ca2+‐ionophore A23187, glutamate agonists, or bradykinin trigger translocation of synaptobrevin/VAMP2 to the plasma membrane with a concomitant disappearance of D‐serine from the regulated secretory pathway. Our results provide morphological evidence for a vesicular storage of D‐serine in the regulated secretory pathway and the possible recruitment of these stores by Ca2+ mobilization to release D‐serine. © 2008 Wiley‐Liss, Inc.
GLT‐1 expression and Glu uptake in rat cerebral cortex are increased by phencyclidine
Authors: Fattorini Giorgia , Melone Marcello , Bragina Luca , Candiracci Chiara , Cozzi Andrea , Pellegrini Giampietro Domenico E. , Torres‐Ramos Monica , Pérez‐Samartín Alberto , Matute Carlos , Conti Fiorenzo 
Published: July 2008

AbstractUsing western blottings, microdialysis, and functional assays we tested the hypothesis that phencyclidine (PCP) modifies the expression and function of glutamate (Glu) transporters in the rat frontal cortex. Western blotting studies revealed that administration of PCP (10 mg/kg/day; 7 days) increased significantly the expression of the astrocytic Glu transporter GLT‐1/EAAT2. Functional studies showed that PCP increased significantly Na+‐dependent Glu uptake in slices and in neuron/astrocyte co‐cultures, and microdialysis studies evidenced that PCP treatment reduced basal Glu output. In our experimental conditions, PCP did not induce toxicity. These studies show that PCP increases the expression of GLT‐1 in the cerebral cortex, thereby increasing Glu uptake and reducing extracellular [Glu]. © 2008 Wiley‐Liss, Inc.
Retracted:Integrated specialty mental health care among older minorities improves access but not outcomes: results of the PRISMe study
Authors: Areán Patricia A. , Ayalon Liat , Jin Chengshi , McCulloch Charles E. , Linkins Karen , Chen Hongtu , McDonnell‐Herr Betsy , Levkoff Sue , Estes Carroll 
Published: July 2008

AbstractThis paper, by Patricia A. Areán, Liat Ayalon, Chengshi Jin, Charles E. McCulloch, Karen Linkins, Hongtu Chen, Betsy McDonnell‐Herr, Sue Levkoff and Carroll Estes has been retracted by agreement between the journal Editors and John Wiley & Sons, Ltd. The retraction has been agreed due to this being the unrevised version of the article. The final accepted version of this manuscript can now be found with the following identification. DOI: 10.1002/gps.2100.The Editors of International Journal of Geriatric Psychiatry
Stressful life events in older bipolar patients
Authors: Beyer John L. , Kuchibhatla Maragatha , Cassidy Frederick , Krishnan K. Ranga R 
Published: July 2008

AbstractObjectiveTheories about the impact of stressful life events (SLE) in bipolar disorder have focused on their role early in the disease. Few studies have examined SLE in older bipolar patients. We wanted to assess the impact of SLE in late life bipolar disorderMethodsWe evaluated negative SLE experienced by older bipolar subjects compared with younger bipolar subjects and older controls for number, type, and their association with phase of illness, age of onset, and previous episodes.ResultsBoth younger and older bipolar subjects have more SLE than similarly aged controls. There was no significant difference in the number of stressors that younger and older bipolar subjects experienced, based on mood state, previous episodes, or age‐of‐onset. Both older and younger depressed bipolar subjects reported more SLE in the previous 12 months compared with those in a manic state.ConclusionsNegative SLE are much more prevalent in bipolar patients compared with age‐matched controls, and continue to be frequent in later life. Copyright © 2008 John Wiley & Sons, Ltd.
Major depression and emergency medical services utilization in community‐dwelling elderly persons with disabilities
Authors: Lee Benjamin W. , Conwell Yeates , Shah Manish N. , Barker William H. , Delavan Rachel L. , Friedman Bruce 
Published: July 2008

AbstractObjectiveTo examine the association between major depression and emergency medical services (EMS) use by community‐dwelling older adults with disabilities.MethodsA prospective observational.study including 1,444 participants age 65+ in 19 counties in three US states that participated in the Medicare Primary and Consumer‐Directed Care Demonstration. Eligibility criteria included needing or receiving help with either 2+ activities of daily living (ADLs) or 3+ instrumental ADLs, and having received recent significant healthcare services use. The presence of major depression was measured at baseline by the MINI Major Depressive Episode module. EMS utilization data for the following 2 years were obtained from a daily journal concurrently completed by each subject or a caregiver.ResultsMore persons with major depression (43%) than without (35%) reported EMS use. When other factors were controlled in a logistic regression model, this effect was no longer statistically significant. However, of those with at least one episode of EMS transport, the depressed reported significantly (25%) more episodes (mean = 2.10) than the non‐depressed (mean = 1.68). Major depression was significantly associated with more EMS episodes in both Poisson (Z = 1.99; p = 0.047) and ordinary least squares (t = 2.08; p = 0.038) regression models.ConclusionsDepressed disabled older adults who utilize EMS have more EMS episodes than those without depression. This higher use may be driven in part by affective illness. Research is needed to determine whether more EMS episodes are necessary to address symptoms of major depression, especially suicidal ideation, or whether they are due to other illnesses that are exacerbated by symptoms of major depression. Copyright © 2008 John Wiley & Sons, Ltd.