bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evidence for a disorder of locomotor timing in Huntington's disease
Authors: Bilney Belinda , Morris Meg E. , Churchyard Andrew , Chiu Edmond , Georgiou‐Karistianis Nellie 
Published: September 2004

AbstractDisturbances of walking have been described in people with Huntington's disease (HD), although the nature of the deficits have not yet been well defined. The purpose of this investigation was to determine whether people with HD have a deficit in the regulation of footstep timing during walking. The footstep patterns of 30 people with HD and 30 matched comparisons were measured at self‐selected slow, preferred, and fast speeds. Subjects were also instructed to match their footsteps to auditory metronome cues set at 80 and 120 beats per minute. Gait speed, cadence, stride length, and double limb support as a percentage of the gait cycle were measured using a computerized foot‐switch system. People with HD demonstrated a disorder in their ability to regulate cadence, manifest as a reduced step frequency when walking at preferred speed and when required to increase their speed. For all walking conditions, people with HD had increased variability of footstep cadence. They also had difficulty synchronizing their footstep timing to an auditory cue. For all walking conditions, people with HD had reduced stride length. Thus, in HD, there is a disorder in the regulation of footstep timing, with increased variability, a restricted cadence range, difficulty synchronizing footsteps to an auditory cue and reduced stride length. The exact neural correlates of this timing disorder are yet to be determined. © 2004 Movement Disorder Society
Dynamics of non‐linear wave equations
Authors: Todorova Grozdena 
Published: September 2004

AbstractWe present several stability/instability results for the ground‐state standing waves and high‐energy‐bound‐state standing waves for the NLKG, NLS and NLDW equations. At the end of the paper we present a number of open problems. Copyright © 2004 John Wiley & Sons, Ltd.
Existence and non‐existence of global solutions of a non‐local wave equation
Authors: Ackleh Azmy S. , Deng Keng 
Published: September 2004

AbstractWe study the initial value problem

where $ \|u(\cdot,t)\| = \int \nolimits ^ {\infty} _ {- \infty}\varphi(x) | u( x,t ) | {\rm{ d }} x$ with φ(x)⩾0 and $ \int \nolimits^{\infty} _ {-\infty} \varphi (x) \, {\rm{d}}x\,= 1$. We show that solutions exist globally for 0<p⩽1, while they blow up in finite time if p>1. We also present the growth rate at blow‐up. Copyright © 2004 John Wiley & Sons, Ltd.
Inward linear perturbation can produce unbounded solutions
Authors: Ninomiya Hirokazu , Weinberger Hans F. 
Published: September 2004

AbstractOne may expect that if one adds a vector field which points toward the origin to the right‐hand side of a first‐order system of ordinary differential equations for which the origin is globally stable, then the origin is globally stable for the new system as well. The purpose of this note is to present an example which shows that this apparently obvious statement is, in fact, false. Copyright © 2004 John Wiley & Sons, Ltd.
Uniform blow‐up profile and boundary behaviour for a non‐local reaction–diffusion equation with critical damping
Authors: Souplet Philippe 
Published: September 2004

AbstractWe consider the Dirichlet problem for a non‐local reaction–diffusion equation with integral source term and local damping involving power non‐linearities. It is known from previous work that for subcritical damping, the blow‐up is global and the blow‐up profile is uniform on all compact subsets of the domain. In this paper, we address the critical case. It turns out that the blow‐up profile is still uniform. Also we compute the sharp blow‐up rate and we find that, unlike in the subcritical case, the blow‐up rate reveals the influence of the damping term.Next, we give precise estimates of the solution in the boundary layer and show that the width of the boundary layer behaves like $\sqrt {T-t}$ as t approaches the blow‐up time T. Even in the subcritical case, this last property was known only for powers p<2. Here, we remove this restriction on p. Some other non‐local equations are also discussed. Copyright © 2004 John Wiley & Sons, Ltd.
On creating a nonisotropic propagation environment inside a scattered field chamber
Authors: Otterskog Magnus , Madsén Kent 
Published: September 2004

AbstractA traditional reverberation chamber creates a statistically isotropic test environment. Tests of communication devices may demand different environments to be able to test, for example, the influence of a diversity antenna. Here, a simple way of altering the distribution of plane waves incident on the device under test is presented. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 43: 192–195, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20417
A multilevel fast multipole algorithm for electrically small composite structures
Authors: Chu Yun‐Hui , Chew Weng Cho 
Published: September 2004

AbstractA multi‐tree scheme to apply the low‐frequency multilevel fast multipole algorithm to composite structures is presented, so that O(N) CPU time and memory usage are obtained. The convenience of “plug and play” in electromagnetic simulation is illustrated in the scenario of contact‐region modeling with an inconsistent mesh. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 43: 202–207, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20419
A fundamental study on the improvement of indoor propagation for wireless LAN communication by an EM wave absorber
Authors: Kimura Ken‐Ichi , Hashimoto Osamu 
Published: September 2004

AbstractIndoor propagation is conducted in an experimental room, in order to estimate the setting absorber for an improved wireless LAN communication environment. Comparison of well reflected environment, replacing of one side wall to the developed absorber makes the average delay profile half, and further replacing of ceiling makes that 1/4. Simulation using the ray‐tracing method is also performed to confirm the effectiveness. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 43: 226–228, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20425
Power coupling between two step‐index multimode fibers of different numerical apertures with an angular misalignment
Authors: Gao Cheng , Farrell Gerald 
Published: September 2004

AbstractThe coupling efficiency between two step‐index multimode fibers of different numerical apertures with an angular misalignment is calculated. The theory is presented using radiometry and geometrical optics. The limit case of the calculation is consistent with a previously published result. Applications include power launching between two types of fibers with different numerical apertures, for example, silica fiber and plastic optical fiber (POF) with an angular misalignment. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 43: 231–234, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20427
A robust approach for derivation of new class of closed‐form Green's functions for microstrip structures
Authors: Kim E. J. , Lee Y. S. , Ko J. H. , Cho Y. K. 
Published: September 2004

AbstractBased upon three‐level approximation and the steepest descent path (SDP) method, we consider a robust approach for the derivation of a new class of closed‐form Green's functions for microstrip structures. Some numerical results are presented for the validation of the present method. It is observed that this method can provide a more accurate evaluation of the spatial Green's functions than the previous method, even without the advance investigation of the spectral functions, over a wide frequency range. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 43: 235–238, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20428
Experimental study of a top‐loaded cylindrical monopole antenna with a truncated‐conical ground plane
Authors: Liu Yung‐Tao , Su Che‐Wei , Wong Kin‐Lu , Tang Chia‐Lun 
Published: September 2004

AbstractThis paper presents an experimental study of a low‐profile, top‐loaded cylindrical monopole antenna with a truncated‐conical ground plane. The cylindrical monopole antenna has omnidirectional radiation and is suitable for WLAN access‐point application. By varying the dimensions of the truncated‐conical ground plane, the maximum radiation direction and 3‐dB beamwidth of the monopole's omnidirectional radiation pattern can be effectively controlled, thus making it possible to achieve an optimized radiation coverage area for various practical applications. The experimental results for operating in the 2.4‐GHz WLAN band are presented and discussed. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 43: 245–247, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20432
Improvement of the coding performance of SSFBG en/decoder by apodization technique
Authors: Wang Xu , Nishiki Akihiko , Kitayama Ken‐Ichi 
Published: September 2004

AbstractThe conflict between the good coding performance and high reflectivity of the superstructure fiber Bragg grating (SSFBG) en/decoder for coherent optical code division multiple access (OCDMA) is analyzed in this paper. Apodization along grating length is proposed for solving this problem for the first time. By using a simple feedback‐searching procedure, an apodization profile for a 15‐chip SSFBG is successfully generated and high reflectivity and a high P/W ratio are exhibited simultaneously. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 43: 247–250, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20433
Design of wide‐band band‐pass filters using discrete‐time domain techniques
Authors: Tsai Lin‐Chuan , Chen Kuo‐Lung , Hsue Ching‐Wen 
Published: September 2004

AbstractA transmission‐line configuration consisting of equal‐length two‐section open stubs, serial lines, and short stubs is employed to emulate the Z‐domain transfer function of a wideband band‐pass filter. Both mitering and slots are used to reduce the discontinuity effect caused by the abrupt changes of characteristic impedances of transmission lines. A wideband filter is realized in the form of microstrip lines and its frequency responses are measured to validate this novel method. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 43: 264–266, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20438
Efficient evaluation of nonredundant moment of method matrix elements for electrically large objects
Authors: See Kye Yak , Liu Zhihong 
Published: September 2004

AbstractA computationally efficient technique is developed to precompute nonredundant elements for moment‐method matrix. This technique reduces the solution time of moment of method (MoM) analysis by 20% to 40%, especially for modelling objects the size of several wavelengths. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 43: 266–268, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20439
Comments on “Direct Extraction Technique for a Small‐Signal MOSFET Equivalent Circuit with Substrate Parameters”
Authors: Torres‐Torres Reydezel 
Published: September 2004

Abstract© 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 43: 268, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20440
Response to comments on “A Direct Extraction Technique for a Small‐Signal MOSFET Equivalent Circuit with Substrate Parameters”
Authors: Lee Seonghearn 
Published: September 2004

Abstract© 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 43: 269, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20441
Conformational insights into furo‐ and thieno[2,3‐b]indolines derived from coupling constants and molecular modeling
Authors: Morales‐Ríos Martha S. , Santos‐Sánchez Norma F. , Pérez‐Rojas Nadia A. , Joseph‐Nathan Pedro 
Published: September 2004

AbstractThe extent to which conformational preferences of fused heterocyclic five‐membered rings change with the nature of the heteroatom (O and S) was investigated in furo‐ (1, 2) and thieno[2,3‐b]indolines (3, 4) by the combined use of 1H NMR spectroscopy and density functional theory (DFT) calculations. In contrast to the behavior observed for pyrroloindolines, the furo‐ and thienoindolines exist in solution in only one conformer, with structures in the 2E–2T3 (1,2) and 2T3–E (3,4) North/West region of the pseudorotational wheel, and with pseudorotation phase angles (P) of 315.8, 311.6, 337.2 and 331.6°, respectively. Copyright © 2004 John Wiley & Sons, Ltd.
A1,3‐strain mediated epimerization of 2e,3e,5e,6e‐tetraarylpiperidin‐4‐one oximes
Authors: Srinivasan M. , Perumal S. , Selvaraj S. 
Published: September 2004

AbstractA series of tri‐ and tetraarylpiperidin‐4‐one oximes were synthesized from 2e,3e,6e‐tri‐ and 2e,3e,5e,6e‐tetraarylpiperidin‐4‐ones, respectively. In the case of the latter compounds, oximation is accompanied by epimerization at C‐5 to avoid the A1,3‐strain between the oxime OH group and the 5e‐aryl ring of the initially formed oxime resulting in 2e,3e,5a,6e‐tetraarylpiperidin‐4‐one oximes. 1H, 13C and 2D NMR spectroscopic data were employed to characterize and investigate the stereochemistry of these compounds. Copyright © 2004 John Wiley & Sons, Ltd.
Plasticity of nonneuronal brain tissue: Roles in developmental disorders
Authors: Dong Willie K. , Greenough William T. 
Published: September 2004

AbstractNeuronal and nonneuronal plasticity are both affected by environmental and experiential factors. Remodeling of existing neurons induced by such factors has been observed throughout the brain, and includes alterations in dendritic field dimensions, synaptogenesis, and synaptic morphology. The brain loci affected by these plastic neuronal changes are dependent on the type of experience and learning. Increased neurogenesis in the hippocampal dentate gyrus is a well‐documented response to environmental complexity (“enrichment”) and learning. Exposure to challenging experiences and learning opportunities also alters existing glial cells (i.e., astrocytes and oligodendrocytes), and up‐regulates gliogenesis, in the cerebral cortex and cerebellum. Such glial plasticity often parallels neuronal remodeling in both time and place, and this enhanced morphological synergism may be important for optimizing the functional interaction between glial cells and neurons. Aberrant structural plasticity of nonneuronal elements is a contributing factor, as is aberrant neuron plasticity, to neurological and developmental disorders such as epilepsy, autism, and mental retardation (i.e., fragile X syndrome). Some of these nonneuronal pathologies include abnormal cerebral and cerebellar white matter and myelin‐related proteins in autism; abnormal myelin basic protein in fragile X syndrome (FXS); and abnormal astrocytes in autism, FXS, and epilepsy. A number of recent studies demonstrate the possibility of using environmental and experiential intervention to reduce or ameliorate some of the neuronal and nonneuronal abnormalities, as well as behavioral deficits, present in these neurological and developmental disorders. MRDD Research Reviews 2004;10:85–90. © 2004 Wiley‐Liss, Inc.
Environmental complexity and central nervous system development and function
Authors: Lewis Mark H. 
Published: September 2004

AbstractEnvironmental restriction or deprivation early in development can induce social, cognitive, affective, and motor abnormalities similar to those associated with autism. Conversely, rearing animals in larger, more complex environments results in enhanced brain structure and function, including increased brain weight, dendritic branching, neurogenesis, gene expression, and improved learning and memory. Moreover, in animal models of CNS insult (e.g., gene deletion), a more complex environment has attenuated or prevented the sequelae of the insult. Of relevance is the prevention of seizures and attenuation of their neuropathological sequelae as a consequence of exposure to a more complex environment. Relatively little attention, however, has been given to the issue of sensitive periods associated with such effects, the relative importance of social versus inanimate stimulation, or the unique contribution of exercise. Our studies have examined the effects of environmental complexity on the development of the restricted, repetitive behavior commonly observed in individuals with autism. In this model, a more complex environment substantially attenuates the development of the spontaneous and persistent stereotypies observed in deer mice reared in standard laboratory cages. Our findings support a sensitive period for such effects and suggest that early enrichment may have persistent neuroprotective effects after the animal is returned to a standard cage environment. Attenuation or prevention of repetitive behavior by environmental complexity was associated with increased neuronal metabolic activity, increased dendritic spine density, and elevated neurotrophin (BDNF) levels in brain regions that are part of cortical–basal ganglia circuitry. These effects were not observed in limbic areas such as the hippocampus. MRDD Research Reviews 2004;10:91–95. © 2004 Wiley‐Liss, Inc.
Analysis of soil consolidation by vertical drains with double porosity model
Authors: Wang Xu‐Sheng , Jiao Jiu Jimmy 
Published: September 2004

AbstractThe soil around a drain well is traditionally divided into smeared zone and undisturbed zone with constant hydraulic conductivity. In reality, hydraulic conductivity of the soil changes continuously and it may not be always appropriate to approximate its distribution with two zones. In this study, the horizontal hydraulic conductivity of the soil is described by an arbitrary function of radial distance. The horizontal flow under equal strain condition is analysed for a soil–drain system with a circular or regular polygonal boundary. It is found that the horizontal flow can be generally characterized with a linear equation in which the flow rate of water through soil–drain interface is proportional to the difference between the average excess pore pressure in the soil and the excess pore pressure in the drain well. The water exchange between the drain and the soil is analogous to that between fractures and matrix in a double porosity system, a popular conceptual model of fracture rocks. On the basis of this characterization, a simplified approach to analyse soil–drain systems is developed with one‐dimensional double porosity model (DPM). Analytical solutions for both fully and partially penetrating drains are derived. The solution for partially penetrating drains is compared with both numerical and approximate analytical results in literature. Copyright © 2004 John Wiley & Sons, Ltd.
A re‐investigation of the low Reynolds number uniform flow past a porous spherical shell
Authors: Hsu H. J. , Huang L. H. , Hsieh P. C. 
Published: September 2004

AbstractThis work reinvestigates the flow field of a uniform flow past a porous spherical shell based on Song and Huang's (2000) theory of laminar poroelastic media flow with proper boundary conditions. The analytical solution of this study not only indicates viscous effects inside the porous spherical shell, but it also preserves the continuities of tangential velocity and shear stress at the interfaces. The result reveals that as the porosity approaches unity, the flow is entirely comprised of the incident stream; as the porosity approaches zero, the well‐known Stokes' solution of a uniform flow past a sphere with low Reynolds number is obtained. Copyright © 2004 John Wiley & Sons, Ltd.
Pelvic floor muscle function in continent and stress urinary incontinent women using dynamometric measurements
Authors: Morin Mélanie , Bourbonnais D. , Gravel D. , Dumoulin C. , Lemieux M.‐C. 
Published: September 2004

AbstractAimsTo compare the pelvic floor muscle (PFM) function in continent and stress urinary incontinent women using dynamometric measurements.MethodsThirty continent women and 59 women suffering from stress urinary incontinence (SUI), aged between 21 and 44 and parous, participated in the study. An instrumented speculum was used to assess the static parameters of the PFM: (1) passive force at 19 and 24 mm of vaginal aperture (antero‐posterior diameter), (2) maximal strength in a self‐paced effort at both apertures, (3) rate of force development and number of contractions during a protocol of rapidly repeated 15‐sec contractions, and lastly (4) absolute endurance recorded over a 90‐sec period during a sustained maximal contraction. The parameters described in the two latter conditions were assessed at the aperture of 19 mm. Analyses of covariance were used to control the confounding variables of age and parity when comparing the PFM function in the continent and incontinent women.ResultsThe continent women demonstrated higher passive force at both openings and a higher absolute endurance as compared to the incontinent women (P ≤ 0.01). In the protocol of rapidly repeated contractions, the rate of force development and number of contractions were both lower in the incontinent subjects (P ≤ 0.01). The differences between the two groups for maximal strength at the 19‐ and 24‐mm apertures did not reach the statistically significant level.ConclusionsThe PFM function is impaired in incontinent women. The assessment of PFM should not be restricted to maximal strength. Other parameters that discriminate between continent and incontinent women need to be added to the PFM assessment in both clinical and research settings. © 2004 Wiley‐Liss, Inc.
Force–length relationship in the pelvic floor muscles under transverse vaginal distension: A method study in healthy women
Authors: Verelst M. , Leivseth G. 
Published: September 2004

AbstractAimsThe purpose of this study was to investigate whether there is a relationship between changes in the diameter of the urogenital hiatus and force developed in pelvic floor musculature. In addition, we wanted to examine the reliability of the method that measures force development in the pelvic floor in the transverse direction of the urogenital hiatus.Materials and MethodsPassive and total force in the pelvic floor was measured with an intra‐vaginal device in 20 healthy parous volunteers. The measurements were done with a consecutively increasing diameter in the transverse plane of the urogenital hiatus. The procedure was repeated with a few days interval.ResultsThe measurements show an increase in force with an increasing device‐diameter. The results are reliable at all the diameters tested, estimated by the within‐subject day‐to‐day variability which was non‐significant. The 40 mm diameter device is most favourable, estimated by Bland Altman plots of the test–retest measurements.ConclusionsForce development in pelvic floor muscles increased as a function of vaginal diameter when measured in the frontal plane. The measurements were reliable at all the different diameters chosen. © 2004 Wiley‐Liss, Inc.