bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fetal brain activity in response to a visual stimulus
Authors: Fulford Jonathan , Vadeyar Shantala H. , Dodampahala Senani H. , Moore Rachel J. , Young Paul , Baker Philip N. , James David K. , Gowland Penny A. 
Published: December 2003

AbstractPrevious studies have demonstrated the use of functional magnetic resonance imaging (fMRI) to assess fetal brain activity. To extend these studies, a fetal fMRI experiment using a visual stimulus has been performed at 0.5 T. This used a block fMRI paradigm with a bright, constant‐intensity light source being shone at the maternal abdomen for 8 sec followed by 16 sec of darkness. This was repeated typically 40 times on nine subjects all of whom were greater than 36 weeks gestational age. Of these, one could not be analysed due to motion, three did not show significant activation, and five showed significant activation (P < 0.0085). In all cases, activation was localised within the frontal cortex. Exact localisation was difficult but this may correspond to the frontal eye fields and dorsolateral prefontal cortex. In no cases was significant activation present within the occipital region as would have been expected and was observed in 2/8 adult subjects. Hum. Brain Mapping 20:239–245, 2003. © 2003 Wiley‐Liss, Inc.
Detecting low‐frequency functional connectivity in fMRI using a self‐organizing map (SOM) algorithm
Authors: Peltier Scott J. , Polk Thad A. , Noll Douglas C. 
Published: December 2003

AbstractLow‐frequency oscillations (<0.08 Hz) have been detected in functional MRI studies, and appear to be synchronized between functionally related areas. A current challenge is to detect these patterns without using an external reference. Self‐organizing maps (SOMs) offer a way to automatically group data without requiring a user‐biased reference function or region of interest. Resting state functional MRI data was classified using a self‐organizing map (SOM). Functional connectivity between the left and right motor cortices was detected in five subjects, and was comparable to results from a reference‐based approach. SOMs are shown to be an attractive option in detecting functional connectivity using a model‐free approach. Hum. Brain Mapping 20:220–226, 2003. © 2003 Wiley‐Liss, Inc.
Willingness to pay for a QALY
Authors: Gyrd‐Hansen Dorte 
Published: December 2003

AbstractA willingness to pay (WTP) per quality‐adjusted‐life year (QALY) of DKK 88 was estimated on the basis of elicited preferences for health states. The WTP per QALY estimate presented here differs considerably from that implied in contingent valuation studies, suggesting that WTP for reducing risk of death is based on other preference structures than is ex post WTP for improvements in quality of life. Results further suggest that different preference structures may exist when respondents are faced with WTP questions in which case elimination of minor health problems are associated with negligible utility. Copyright © 2003 John Wiley & Sons, Ltd.
Stack unit mapping of coastal aquifer to predict and control sea water intrusion using remote sensing and a geographical information system
Authors: Moses Edwin J. , Thirumalaivasan D. 
Published: December 2003

AbstractAquifers are inherently susceptible to contamination and coastal aquifers in specific are highly vulnerable to sea water intrusion. For efficient planning and management of coastal aquifers in Kayalpattu and Tiruchopuram villages, which extend over 4·05 km2, it is essential to delineate and predict the extent of intrusion into the shallow aquifer. Management of ground water in coastal aquifers is composed of major elements that should be properly evaluated, and special attention is given to the sea water intrusion problem. Different data, like hydro‐geomorphological and depth‐wise iso‐apparent resistivity, are integrated spatially using a geographical information system. The stack‐unit mapping approach is used to delineate the zones with iso‐apparent resistivity of less than 10 Ω m have been found to be increasing in areal extent with reference to depth. Copyright © 2003 John Wiley & Sons, Ltd.
The influence of diurnal temperatures on the hydrochemistry of a tufa‐depositing stream
Authors: Drysdale R. , Lucas S. , Carthew K. 
Published: December 2003

AbstractAt‐a‐station diurnal variations in carbonate hydrochemistry were measured during four observation periods at Davys Creek, a tufa‐depositing stream in central NSW, Australia. Major ion concentrations and continuously logged measurements of specific conductivity, pH and temperature showed that changes in the amount of CaCO3 deposited upstream of the study reach were directly related to changes in diurnal water temperatures, which control the rate of CO2 efflux to the atmosphere. The greatest upstream losses occurred during the mid‐afternoon water temperature peak, whereas the lowest upstream losses occurred at sunrise, when water temperatures were at their lowest. Cloudy days at all times of the year produced small diurnal water temperatures ranges (c. 2–5°C) and, consequently, relatively small changes in upstream CaCO3 loss (23–50 mg L−1) through the day. Clear sunny days, especially during summer months, produced large diurnal water temperature changes (up to c. 11°C), which in turn triggered diurnal changes in upstream CaCO3 loss of up to 100 mg L−1. By implication, the active reach of tufa deposition must advance downstream and increase in length during the evening and vice versa during the day. Given that the temperature of Davys Creek waters are a function of insolation, changes in the reach of tufa deposition under baseflow conditions are a direct function of the prevailing weather. This has implications for the palaeoclimatic interpretation of fossil tufa deposits. Copyright © 2003 John Wiley & Sons, Ltd.
Hydromorphological and biological factors influencing sediment and phosphorus loss via bank erosion in small lowland rural streams in Denmark
Authors: Laubel A. , Kronvang B. , Hald A. B. , Jensen C. 
Published: December 2003

AbstractBank erosion was measured at 91 stream banks located in 15 Danish rural 1st and 2nd order streams over a 2‐year period. Our aims were firstly to examine factors controlling spatial variation in bank erosion, secondly to estimate sediment and phosphorus (P) loss via bank erosion. The overall mean bank erosion rate was 11 mm year−1. Bank erosion rate over the 2‐year period was significantly related to a number of site‐specific characteristics, including bank angle, bank vegetation cover, overhanging bank and estimated stream power. An empirical model for bank erosion based on these descriptive variables yielded a 55% explanation of the observed spatial variation in bank erosion rate. Bank erosion was higher at the lower 50‐cm bank section (20 mm year−1) than at the upper bank (6 mm year−1). Cattle fencing in grazed areas and buffer zones with riparian woodland lowered bank erosion rates. We found that total P content of bank material was high (0·64 g P kg−1) and at the same level as found in agricultural topsoil along the streams. The overall annual catchment loss of bank‐derived clay–silt sediment and total P to streams amounted to 58–72 kg sediment ha−1 and 0·23–0·28 kg P ha−1, respectively. In comparison, the mean annual suspended sediment (SS) and total P losses from 14 similar sized Danish agricultural catchments were 122 kg SS ha−1 and 0·58 kg P ha−1 over the 2‐year study period. Thus, bank erosion seems to be a major contributor of suspended sediment and P in this type of small channelized lowland stream. Copyright © 2003 John Wiley & Sons, Ltd.
Rhythmic cortical myoclonus in a case of HIV‐related encephalopathy
Authors: Canafoglia Laura , Panzica Ferruccio , Franceschetti Silvana , Carriero M. Rita , Ciano Claudia , Scaioli Vidmer , Chiapparini Luisa , Visani Elisa , Avanzini Giuliano 
Published: December 2003

AbstractWe describe a 66‐year‐old, HIV‐seropositive patient presenting with ataxia and upper limb rhythmic myoclonus activated by postural maintenance. Electromyograph (EMG) recordings of the forearm muscles showed 50‐msec bursts, with a frequency of 10 Hz, concurring with frontocentral electroencephalograph (EEG) rhythmic activity. Autoregressive spectral analysis applied to the EEG–EMG traces made it possible to detect significant coherence between the rhythmic EEG discharges and EMG bursts. The amplitude of the middle‐latency somatosensory evoked potentials was increased. Long‐latency reflexes were enhanced. On the basis of the electrophysiological findings, the movement disorder should be considered a rhythmic variant of cortical myoclonus. In our patient, HIV infection may have caused a dysfunction in the central nervous system pathways involving the cerebellum and sensorimotor cortex, similar to that occurring in genetically determined conditions characterised by cortical myoclonus. © 2003 Movement Disorder Society
Phenotypic features of Huntington's disease‐like 2
Authors: Walker Ruth H. , Jankovic Joseph , O'Hearn Elizabeth , Margolis Russell L. 
Published: December 2003

AbstractHuntington's disease‐like 2 is an autosomal dominantly inherited disorder due to an expansion of trinucleotide repeats. It resembles classic Huntington's disease in clinical phenotype, inheritance pattern, and neuropathological features. We highlight the clinical features of this disorder, including chorea, dystonia, parkinsonism, and cognitive deficits. © 2003 Movement Disorder Society
Chronic treatment with small doses of cabergoline prevents dopa‐induced dyskinesias in parkinsonian monkeys
Authors: Bélanger Nancy , Grégoire Laurent , Tahar Abdallah Hadj , Bédard Paul J. 
Published: December 2003

AbstractLevodopa continues to be the most effective agent for the symptomatic treatment of Parkinson's disease (PD). But over time, initial benefits decline in efficacy because of a rise in adverse effects such as dyskinesias. The pathophysiology of levodopa‐induced dyskinesias (LID) is not completely understood, but it appears to result from deficient regulation by dopamine of corticostriatal glutamatergic inputs leading to a cascade of neurochemical changes in the striatum and the output pathways. In the present study, we examined if the addition of small doses of cabergoline (a long‐acting D2 receptor agonist) to levodopa could prevent LID. The major hypothesis is that sustained activation of postsynaptic D2 receptors on medium spiny neurons even by small doses of cabergoline could prevent or reduce LID. The minor hypothesis, and the more controversial of the two, is that the long‐acting stimulation by small doses of cabergoline could diminish the release of glutamate by the corticostriatal pathway and prevent LID. Eight MPTP‐treated monkeys with a long‐standing and stable parkinsonian syndrome and having never received dopaminergic agents were used. Two groups of four were treated for 1 month with levodopa/benserazide administered orally (100 mg/25 mg). The second group received in addition a threshold dose of cabergoline (dose ranging from 0.015 to 0.035 mg/kg, SC). During the treatment, we observed LID in the levodopa group but not in the group receiving levodopa+cabergoline. Furthermore, the combination produced a comparable antiparkinsonian effect in terms of quality but prolonged the duration (by 1 to 2 hours) and increased the locomotion (mean for 2 weeks ≅ 104%). Our data suggest that a small dose of a long‐acting D2 agonist combined with high doses of levodopa could be preventive of LID in patients with PD and could be an alternative to using antiglutamatergic agents for this purpose. © 2003 Movement Disorder Society
Epilepsia partialis continua in progressive multifocal leukoencephalopathy: A motor cortex isolation syndrome
Authors: Berciano José , Leno Carlos , Figols Javier , García Antonio , Polo José M. , Berciano María T. , Ariza Aurelio 
Published: December 2003

AbstractWe describe the clinical and neuropathological features in a patient aged 45 years with progressive multifocal leukoencephalopathy with epilepsia partialis continua. The motor cortex and basal ganglia were preserved. Our findings lend support to the notion of isolation of the motor cortex as the cause of this particular type of focal status epilepticus. © 2003 Movement Disorder Society
Parkinson's disease, subthalamic stimulation, and selection of candidates: A pathological study
Authors: Jarraya Bechir , Bonnet Anne‐Marie , Duyckaerts Charles , Houeto Jean‐Luc , Cornu Philippe , Hauw Jean‐Jacques , Agid Yves 
Published: December 2003

AbstractWe report on a patient with Parkinson's disease (PD) who was moderately improved by stimulation of the subthalamic nucleus (STN) and died 2 years after electrode implantation. After neurosurgery, symptoms that had responded to levodopa treatment preoperatively continued to improve. Postural instability, dysarthria, and cognitive impairment continued to worsen, despite STN stimulation and levodopa treatment. Postmortem examination of the brain confirmed the diagnosis of PD and showed that the electrodes had been correctly positioned within the STN. The failure of STN stimulation in this patient confirms the importance of screening and excluding patients from surgery with evolving parkinsonian axial symptoms or cognitive impairment. © 2003 Movement Disorder Society
Subtraction brain SPECT imaging in a patient with gait ignition failure
Authors: Lee Phil Hyu , Lee Jin Soo , Lee Myung Hoon , Lee Jung Doo , Huh Kyoon 
Published: December 2003

AbstractThe precise anatomical location and pathophysiology of gait ignition failure (GIF) is poorly understood. We investigated the cerebral perfusion patterns using subtraction brain single photon emission computed tomography (SPECT) in a patient with GIF. Subtraction brain SPECT imaging revealed an increased activity in the region of right ventrolateral midbrain and ventral medulla. © 2003 Movement Disorder Society
Auditory startle response in cervical dystonia
Authors: Müller Jörg , Kofler Markus , Wenning Gregor K. , Seppi Klaus , Valls‐Solé Josep , Poewe Werner 
Published: December 2003

AbstractThe excitability of brainstem neurons is abnormally enhanced in patients with cervical dystonia (CD), but the extend of such abnormality is not known. We examined whether patients with CD showed abnormalities in the auditory startle response (ASR), a brainstem reflex elicited by an unexpected loud stimulus. Thirteen patients with CD were investigated 3 months after botulinum toxin treatment. Thirteen healthy volunteers served as controls. ASRs were elicited by binaural high‐intensity auditory stimuli. Reflex electromyographic (EMG) activity was recorded simultaneously with surface electrodes bilaterally from masseter, orbicularis oculi, sternocleidomastoid, and biceps brachii muscles. We found that ASR onset latencies were similar for patients and controls. CD patients had significantly lower ASR probabilities than controls (P = 0.007). ASR area under the curve was significantly smaller in CD patients (P = 0.017). Similar to controls, patients showed a significant habituation of ASR (P < 0.001, each); however, CD patients showed a prolonged tonic or phasic EMG activity after the initial ASR that was not observed in controls. Normal latencies and recruitment pattern indicate a preserved organization of intrinsic neural pathways mediating ASR in CD. Reduced ASR probability and magnitude as well as prolonged EMG activity after the proper startle response corroborate and extend previous findings on brainstem dysfunction in CD. © 2003 Movement Disorder Society
Magnetic resonance spectroscopy of cerebral cortex is normal in hereditary hyperekplexia due to mutations in the GLRA1 gene
Authors: Tijssen Marina A.J. , Brown Peter , MacManus David , McLean Mary A. , Davie Charles 
Published: December 2003

AbstractExcessive startling and stiffness in hereditary hyperekplexia has been attributed to lack of inhibition at either the cortical or brainstem level. Six patients with hereditary hyperekplexia (HH) and a confirmed mutation in the gene encoding the α1 subunit of the glycine receptor (GLRA1) underwent single voxel 1H magnetic resonance spectroscopy (MRS) of the brainstem and an area of frontal cortex and white matter using a method that allows absolute quantification of metabolites. The results of MRS were within normal limits, although there was a tendency for the neuronal marker N‐acetyl aspartate to be reduced in the brainstem of patients compared with that in controls. Thus, we found no evidence to support a deficit in the cerebral cortex in patients with hereditary hyperekplexia due to mutations in the GLRA1 gene. © 2003 Movement Disorder Society
Dystonia in a patient with ring chromosome 21
Authors: Hou Craig E. , Schlaggar Bradley L. , Racette Brad A. 
Published: December 2003

AbstractDystonia associated with chromosomal abnormalities is typically attributed to chromosomal deletions. We describe a patient with ring chromosome 21, with karyotype 46XX,r(21)(p11.2q22.3); 46,XX,dic r(21)(p11.2q22.3); 45, XX, –21, who developed childhood onset cervical dystonia. © 2003 Movement Disorder Society
Deficits induced by quinolinic acid lesion to the striatum in a position discrimination and reversal task are ameliorated by permanent and temporary lesion to the globus pallidus: A potential novel treatment in a rat model of Huntington's disease
Authors: Joel Daphna , Ayalon Liat , Tarrasch Ricardo , Weiner Ina 
Published: December 2003

AbstractSymptoms in the early stages of Huntington's disease (HD) are assumed to reflect basal ganglia circuit dysfunction secondary to degeneration of striatal projections to the external segment of the globus pallidus (GPe). The hypothesis that GPe lesion would ameliorate HD symptoms by “normalizing” the circuit's functioning was tested in a rat model of this disease. The performance of rats sustaining quinolinic acid lesion to the striatum (a rat model of HD) in a position discrimination and reversal task was compared with the performance of rats sustaining in addition a bilateral excitotoxic lesion to the globus pallidus (GP) carried out simultaneously with the striatal lesion (Experiment 1) or 1 month after the striatal lesion (Experiment 2), as well as a unilateral temporary lesion of the GP (Experiment 3). The striatal lesion‐induced deficit in the task was effectively reversed by a bilateral excitotoxic GP lesion carried out simultaneously or 1 month after the striatal lesion, as well as by a temporary unilateral GP inactivation. Given that a similar dysfunction of basal ganglia circuitry is thought to subserve the behavioral alterations seen in quinolinic acid lesioned rats and some of the symptoms in HD, these results raise the possibility that lesion or inactivation of the GPe may alleviate some of HD symptoms. © 2003 Movement Disorder Society
Stochastic computational modelling of highly heterogeneous poroelastic media with long‐range correlations
Authors: Frias Diego G. , Murad Márcio A. , Pereira Felipe 
Published: December 2003

AbstractThe compaction of highly heterogeneous poroelastic reservoirs with the geology characterized by long‐range correlations displaying fractal character is investigated within the framework of the stochastic computational modelling. The influence of reservoir heterogeneity upon the magnitude of the stresses induced in the porous matrix during fluid withdrawal and rock consolidation is analysed by performing ensemble averages over realizations of a log‐normally distributed stationary random hydraulic conductivity field. Considering the statistical distribution of this parameter characterized by a coefficient of variation governing the magnitude of heterogeneity and a correlation function which decays with a power‐law scaling behaviour we show that the combination of these two effects result in an increase in the magnitude of effective stresses of the rock during reservoir depletion. Further, within the framework of a perturbation analysis we show that the randomness in the hydraulic conductivity gives rise to non‐linear corrections in the upscaled poroelastic equations. These corrections are illustrated by a self‐consistent recursive hierarchy of solutions of the stochastic poroelastic equations parametrized by a scale parameter representing the fluctuating log‐conductivity standard deviation. A classical example of land subsidence caused by fluid extraction of a weak reservoir is numerically simulated by performing Monte Carlo simulations in conjunction with finite elements discretizations of the poroelastic equations associated with an ensemble of geologies. Numerical results illustrate the effects of the spatial variability and fractal character of the permeability distribution upon the evolution of the Mohr–Coulomb function of the rock. Copyright © 2004 John Wiley & Sons, Ltd.
Numerical prediction of blast‐induced stress wave from large‐scale underground explosion
Authors: Wu Chengqing , Lu Yong , Hao Hong 
Published: December 2003

AbstractThis paper presents a numerical model for predicting the dynamic response of rock mass subjected to large‐scale underground explosion. The model is calibrated against data obtained from large‐scale field tests. The Hugoniot equation of state for rock mass is adopted to calculate the pressure as a function of mass density. A piecewise linear Drucker–Prager strength criterion including the strain rate effect is employed to model the rock mass behaviour subjected to blast loading. A double scalar damage model accounting for both the compression and tension damage is introduced to simulate the damage zone around the charge chamber caused by blast loading. The model is incorporated into Autodyn3D through its user subroutines. The numerical model is then used to predict the dynamic response of rock mass, in terms of the peak particle velocity (PPV) and peak particle acceleration (PPA) attenuation laws, the damage zone, the particle velocity time histories and their frequency contents for large‐scale underground explosion tests. The computed results are found in good agreement with the field measured data; hence, the proposed model is proven to be adequate for simulating the dynamic response of rock mass subjected to large‐scale underground explosion. Extended numerical analyses indicate that, apart from the charge loading density, the stress wave intensity is also affected, but to a lesser extent, by the charge weight and the charge chamber geometry for large‐scale underground explosions. Copyright © 2004 John Wiley & Sons, Ltd.
Novel applications of bifacial solar cells
Authors: Hezel Rudolf 
Published: December 2003

AbstractUtilizing the light reflected by simple means onto the rear surface of solar cells is an effective way of lowering the cost of solar electricity, since more power is generated per cell. Innovative bifacial photovoltaic modules have been introduced, such as a multi‐functional bifacial PV sun‐shading element which is based on bifacially sensitive solar cells in combination with a white semitransparent reflector back sheet. Not only is sunlight collected by its front and rear surface efficiently converted into electricity, but also diffuse glare‐free daylight is provided. Other applications include relatively narrow bifacial modules installed at a certain distance in front of a reflecting background. In all cases power gains of more than 50% can be achieved with little extra cost compared with monofacial modules. Copyright © 2003 John Wiley & Sons, Ltd.