bluuebunny/crossref_metadata_2025_split huggingface dataset:
Radiologically guided percutaneous fine‐needle aspiration biopsy of pelvic and retroperitoneal masses: A retrospective study of 68 cases
Authors: Guo Ziwen , Kurtycz Daniel F.I. , De Las Casas Luis E. , Hoerl H. Daniel 
Published: September 2002

AbstractFine‐needle aspiration (FNA) of the pelvis and retroperitoneum (excluding the pancreas, kidney, and adrenal masses) has not achieved its full potential as a diagnostic modality. We reviewed 68 percutaneous, radiologically guided FNAs from these locations to assess the clinical utility and complication rate of this procedure. Satisfactory material was obtained in 66 cases (97.1%), of which 37 were deemed positive (55%), 3 suspicious (4%), 4 atypical (6%), and 22 negative (32%) for malignancy; two cases (3%) were unsatisfactory. Compared to biopsy (36 patients) and clinical information, the sensitivity and specificity of FNA for malignancy were 90.2% and 100%, respectively, yielding a positive predictive value of 100% and a negative predictive value of 86.6%. The four false‐negative cases (5.9%) were due to sampling error. One patient had a minor complication (hematoma) from the procedure. We conclude that FNA is the procedure of choice for detecting most malignancies in these two locations. Diagn. Cytopathol. 25:43–49, 2001. © 2001 Wiley‐Liss, Inc.
The dominance of dispersion in the evolution of bed material waves in gravel‐bed rivers
Authors: Lisle Thomas E. , Cui Yantao , Parker Gary , Pizzuto James E. , Dodd Annjanette M. 
Published: September 2002

AbstractBed material waves are temporary zones of sediment accumulation created by large sediment inputs. Recent theoretical, experimental and field studies examine factors influencing dispersion and translation of bed material waves in quasi‐uniform, gravel‐bed channels. Exchanges of sediment between a channel and its floodplain are neglected. Within these constraints, two factors influence relative rates of dispersion and translation: (1) interactions between wave topography, flow and bed load transport; and (2) particle‐size differences between wave material and original bed material. Our results indicate that dispersion dominates the evolution of bed material waves in gravel‐bed channels. Significant translation requires a low Froude number, which is uncharacteristic of gravel‐bed channels, and low wave amplitude which, for a large wave, can be achieved only after substantial dispersion. Wave material of small particle size can promote translation, but it primarily increases bed load transport rate and thereby accelerates wave evolution. Copyright © 2001 John Wiley & Sons, Ltd.
An improved automatic analyzer for organic compounds in water based on headspace solid‐phase microextraction (SPME) coupled to gas chromatography
Authors: Belau Eckhard , Grote Christoph , Spiekermann Manfred , Levsen Karsten 
Published: September 2002

AbstractAn automated analyzer based on solid‐phase microextraction (SPME) coupled to gas chromatography (GC) for monitoring organic compounds in water is presented. The instrumental setup, which was tested previously with direct SPME, is now tested in the headspace mode. Memory effects observed in the earlier design were reduced by using glass instead of plastic tubing. Parameters that potentially influence the extraction yield were studied in the laboratory with the use of spiked water samples. These parameters were temperature, salt content, methanol content, pH value, and excess components. The extraction efficiency as a function of the extraction time (absorption profiles) was determined for 24 standard compounds. The method was validated in the laboratory. Good precision (in general <5%) and linearity were observed. With the use of flame ionization, detection limits of quantitation were in the low‐ppb range, sufficient for wastewater monitoring. The instrument was tested continuously for 6 days at the wastewater plant of a chemical company in northern Germany. Better stability and robustness were observed in the headspace SPME compared to the direct SPME. © 2001 John Wiley & Sons, Inc. Field Analyt Chem Technol 5: 37–49, 2001
A linear forecasting model and its application to economic data
Authors: Peters Georg 
Published: September 2002

AbstractWe present a forecasting model based on fuzzy pattern recognition and weighted linear regression. In this model fuzzy pattern recognition is used to find homogeneous fuzzy classes in a heterogeneous data set. It is assumed that the classes represent typical situations. For each class a weighted regression analysis is conducted. The forecasting results obtained by the class regression analysis are aggregated to obtain the ‘overall’ estimation of the regression model. We apply the model to the forecasting of economic data of the USA. Copyright © 2001 John Wiley & Sons, Ltd.
Misspecified prediction for time series
Authors: Choi In‐Bong , Taniguchi Masanobu 
Published: September 2002

AbstractLet {Xt} be a stationary process with spectral density g(λ).It is often that the true structure g(λ) is not completely specified. This paper discusses the problem of misspecified prediction when a conjectured spectral density fθ(λ), θ∈Θ, is fitted to g(λ). Then, constructing the best linear predictor based on fθ(λ), we can evaluate the prediction error M(θ). Since θ is unknown we estimate it by a quasi‐MLE $\hat{\theta}_{Q}$. The second‐order asymptotic approximation of $M(\hat{\theta}_{Q})$ is given. This result is extended to the case when Xt contains some trend, i.e. a time series regression model. These results are very general. Furthermore we evaluate the second‐order asymptotic approximation of $M(\hat{\theta}_{Q})$ for a time series regression model having a long‐memory residual process with the true spectral density g(λ). Since the general formulae of the approximated prediction error are complicated, we provide some numerical examples. Then we illuminate unexpected effects from the misspecification of spectra. Copyright © 2001 John Wiley & Sons, Ltd.
Vasoactive intestinal polypeptide in neuroglia? Immunoelectron microscopic localization in astrocytes of the rat mesencephalon
Authors: Paspalas Constantinos D. , Halasy Katalin , Gerics Balázs , Papadopoulos Georgios C. , Hajós Ferenc 
Published: September 2002

AbstractThe dorsal region of the rat interpeduncular nucleus (IPN) was found highly immunoreactive for vasoactive intestinal polypeptide (VIP). This area appeared as a cap‐like structure at the midcaudal level of the nucleus. Unlike other brain areas, however, VIP immunoreactivity within the “cap” appeared vaguely punctuate with no light microscopically identifiable cell structures. Ultrastructurally, a dense meshwork of VIP‐immunopositive bouton‐laden axons was revealed. Labeled neuronal perikarya were not encountered. Some lightly immunoreactive dendrites were observed. In addition, immunopositive glial profiles were frequently seen. Perikarya and numerous fine processes, occasionally perivascular, identified as astroglia by established ultrastructural criteria, exhibited VIP immunoreactivity. Constant feature of the peptide immunolocalization was the predilection for the intermediate filament bundles of astrocytic perikarya and processes. This was usually accompanied by a thick coating of the inner aspect of glial plasmalemma and, in perikarya, by highly reactive vesicular profiles. Glial immunopositive elements were never seen beyond the boundaries of the diffuse “cap.” In view of the repertoire of metabolic, neurotrophic, and neuroprotective mechanisms in which VIP neurons are involved in conjunction with astroglia, the presence of VIP‐immunoreactive astrocytes in a circumscribed area, confirms the heterogeneity of astrocyte populations. GLIA 34:229–233, 2001. © 2001 Wiley‐Liss, Inc.
Angiotensin receptor‐like immunoreactivity in adult brain white matter astrocytes and oligodendrocytes
Authors: Fogarty David J. , Matute Carlos 
Published: September 2002

AbstractMost of the physiological effects of brain angiotensins are currently believed to be mediated by angiotensin receptors located principally on neurons. However, numerous studies in vitro have demonstrated the presence of functional angiotensin receptors on brain astrocytes, raising the possibility that glial cells may also participate in mediating the effects of the central renin–angiotensin system. Nevertheless, it is uncertain whether these cells in situ express angiotensin receptors, raising questions about the physiological significance of results observed in cell cultures. We have examined the distribution of angiotensin receptor‐like immunoreactivity in glial cells in white matter tracts in the adult CNS, using a panel of antisera to the AT1 and AT2 angiotensin receptors. Antiserum preadsorption and/or Western blot demonstrated the specificity of the antisera in brain tissue. In immunohistochemical experiments, the AT1 antisera selectively labeled AT1‐expressing neurons in the piriform cortex, whereas the AT2 antiserum stained cells in the trigeminal motor nucleus, these being nuclei known to express AT1 and AT2 receptors, respectively. Using double‐label immunohistochemistry, we observed AT1‐ and AT2‐immunoreactive astrocytes and oligodendrocytes in white matter tracts, which include the rat cerebellar white matter, periventricular white matter, and optic nerve, in addition to the bovine corpus callosum and human subcortical white matter. In contrast, astrocytes in the gray matter region of the cerebral cortex were not found to be angiotensin receptor‐like immunoreactive. These results demonstrate the presence of AT1 and/or AT2 angiotensin receptor‐like immunoreactivity in brain white matter macroglial cells in situ and support the idea that glial cells may play a more important role in the central renin‐angiotensin system than previously thought. GLIA 35:131–146, 2001. © 2001 Wiley‐Liss, Inc.
Sensorimotor mapping of the human cerebellum: fMRI evidence of somatotopic organization
Authors: Grodd Wolfgang , Hülsmann Ernst , Lotze Martin , Wildgruber Dirk , Erb Michael 
Published: September 2002

AbstractFunctional magnetic resonance imaging (fMRI) was employed to determine areas of activation in the cerebellar cortex in 46 human subjects during a series of motor tasks. To reduce the variance due to differences in individual anatomy, a specific transformational procedure for the cerebellum was introduced. The activation areas for movements of lips, tongue, hands, and feet were determined and found to be sharply confined to lobules and sublobules and their sagittal zones in the rostral and caudal spino‐cerebellar cortex. There was a clear symmetry mirroring at the midline. The activation mapped as two distinct homunculoid representations. One, a more extended representation, was located upside down in the superior cerebellum, and a second one, doubled and smaller, in the inferior cerebellum. The two representations were remarkably similar to those proposed by Snider and Eldred [1951] five decades ago. In the upper representation, an intralimb somatotopy for the right elbow, wrist, and fingers was revealed. The maps seem to confirm earlier electrophysiological findings of sagittal zones in animals. They differ, however, from micromapping reports on fractured somatotopic maps in the cerebellar cortex of mammals. We assume that the representations that we observed are not solely the result of spatial integration of hemodynamic events underlying the fMRI method and may reflect integration of afferent peripheral and central information in the cerebellar cortex. Hum. Brain Mapping 13:55–73, 2001. © 2001 Wiley‐Liss, Inc.
Analysis and use of FMRI response delays
Authors: Saad Ziad S. , Ropella Kristina M. , Cox Robert W. , DeYoe Edgar A. 
Published: September 2002

AbstractIn this study, we implemented a new method for measuring the temporal delay of functional magnetic resonance imaging (fMRI) responses and then estimated the statistical distribution of response delays evoked by visual stimuli (checkered annuli) within and across voxels in human visual cortex. We assessed delay variability among different cortical sites and between parenchyma and blood vessels. Overall, 81% of all responsive voxels showed activation in phase with the stimulus while the remaining voxels showed antiphase, suppressive responses. Mean delays for activated and suppressed voxels were not significantly different (P< 0.001). Cortical flat maps showed that the pattern of activated and suppressed voxels was dynamically induced and depended on stimulus size. Mean delays for blood vessels were 0.7–2.4 sec longer than for parenchyma (P< 0.01). However, both parenchyma and blood vessels produced responses with long delays. We developed a model to identify and quantify different components contributing to variability in the empirical delay measurements. Within‐voxel changes in delay over time were fully accounted for by the effects of empirically measured fMRI noise with virtually no measurable variability associated with the stimulus‐induced response itself. Across voxels, as much as 47% of the delay variance was also the result of fMRI noise, with the remaining variance reflecting fixed differences in response delay among brain sites. In all cases, the contribution of fMRI noise to the delay variance depended on the noise power at the stimulus frequency. White noise models significantly underestimated the fMRI noise effects. Hum. Brain Mapping 13:74–93, 2001. © 2001 Wiley‐Liss, Inc.
Unusual products in reactions using ethyldimesitylborane, mesityllithium, and carbonyl compounds
Authors: Kawashima Takayuki , Yamashita Naoko , Kannabe Tohru , Okazaki Renji 
Published: September 2002

AbstractUnusual carbonyl adducts, Mes2BCH=CHCHCH3CRR1OH, were obtained by sequential treatment of ethyldimesitylborane with mesityllithium (<1.0 equiv.) and carbonyl compounds instead of the normal adducts, Mes2BCHCH3CRR1OH. A mechanistic study was carried out. © 2001 John Wiley & Sons, Inc. Heteroatom Chem 12:354–357, 2001
Synthesis and structure of pentaphenyl‐telluronium salts of perchlorate and tetrakis{3,5‐bis(trifluoromethyl)phenyl}borate: hypervalent onium compounds
Authors: Minoura Mao , Mukuda Takahiro , Sagami Takao , Akiba Kin‐ya 
Published: September 2002

AbstractThe reaction of pentaphenyltellurium chloride 2 with silver perchlorate afforded the pentaphenyltelluronium salt, Ph5Te+ClO, (1b), and treatment of 2 with silver triflate and sodium tetrakis{3,5‐bis(trifluoromethyl)phenyl}borate provided Ph5Te+[3,5‐(CF3)2C6H3]4B− (1c), which were isolated as stable yellow solids. X‐ray crystallographic analyses of the hypervalent telluronium salts revealed square‐pyramidal geometry around the tellurium, which are rare examples for penta‐substituted main group element compounds. © 2001 John Wiley & Sons, Inc. Heteroatom Chem 12:380–384, 2001
Dissociating hippocampal subregions: A double dissociation between dentate gyrus and CA1
Authors: Gilbert Paul E. , Kesner Raymond P. , Lee Inah 
Published: September 2002

AbstractThis study presents a double dissociation between the dentate gyrus (DG) and CA1. Rats with either DG or CA1 lesions were tested on tasks requiring either spatial or spatial temporal order pattern separation. To assess spatial pattern separation, rats were trained to displace an object which covered a baited food‐well. The rats were then allowed to choose between two identical objects: one covered the same well as the sample phase object (correct choice), and a second object covered a different unbaited well (incorrect choice). Spatial separations of 15–105 cm were used to separate the correct object from the incorrect object. To assess spatial temporal order pattern separation, rats were allowed to visit each arm of a radial eight‐arm maze once in a randomly determined sequence. The rats were then presented with two arms and were required to choose the arm which occurred earliest in the sequence. The choice arms varied according to temporal separation (0, 2, 4, or 6) or the number of arms that occurred between the two choice arms in the sample phase sequence. On each task, once a preoperative criterion was reached, each rat was given either a DG, CA1, or control lesion and then retested. The results demonstrated that DG lesions resulted in a deficit on the spatial task but not the temporal task. In contrast, CA1 lesions resulted in a deficit on the temporal task but not the spatial task. Results suggest that the DG supports spatial pattern separation, whereas CA1 supports temporal pattern separation. Hippocampus 2001;11:626–636. © 2001 Wiley‐Liss, Inc.
Long‐term changes in concentrations and flux of nitrogen in the Mississippi River Basin, USA
Authors: Goolsby Donald A. , Battaglin William A. 
Published: September 2002

AbstractCurrent and historical data show that nitrogen concentrations and flux in the Mississippi River Basin have increased significantly during the past 100 years. Most of the increase observed in the lower Mississippi River has occurred since the early 1970s and is due almost entirely to an increase in nitrate. The current (1980–99) average annual nitrogen (N) flux from the Mississippi Basin to the Gulf of Mexico is about 1 555 500 t year−1, of which about 62% is nitrate‐N. The remaining 38% is organic nitrogen and a small amount of ammonium. The current (1980–99) average nitrate flux to the Gulf is almost three times larger than it was during 1955–70. This increased supply of nitrogen to the Gulf is believed to be partly responsible for the increasing size of a large hypoxic zone that develops along the Louisiana–Texas shelf each summer. This zone of oxygen‐depleted water has doubled in areal extent since it was first measured in 1985. The increase in annual nitrate flux to the Gulf can be largely explained by three factors: increased fertilizer use, annual variability in precipitation and increased streamflow, and the year‐to‐year variability in the amount of nitrogen available in the soil‐ground water system for leaching to streams. The predominant source areas for the nitrogen transported to the Gulf of Mexico are basins draining southern Minnesota, Iowa, Illinois, Indiana, and Ohio. Basins in this region yield 1801 to 3050 kg N km−2 year−1 to streams, several times the N yield of basins outside this region. Published in 2001 by John Wiley & Sons, Ltd.
Water flow and hydraulic characteristics of Japanese red pine and oak trees
Authors: Kobayashi Yoshikazu , Tanaka Tadashi 
Published: September 2002

AbstractTo assess the characteristics of water flow in a tree and the contribution of the stem water storage to transpiration, some field observations were carried out in two natural forests: a Japanese red pine (Pinus densiflora Sieb. et Zucc.) forest and an oak (Quercus mongolica Fish) forest. Water potentials of leaf, stem, root and soil water, sap flow rate, volumetric water content of the stem and micrometeorological factors were measured during the observation periods. Clear diurnal variations in volumetric water content of a stem were observed. It was confirmed that water storage in the stem contributed to the transpiration process. This contribution appeared when the difference in water potential between the root and stem was more than 0·3 MPa. The stem water storage was extracted by the driving force due to the difference of the response of the root and stem water potential to change in the leaf water potential in daytime. The stem capacitance of 1·44 kg MPa−1 for the Japanese red pine and 0·44 kg MPa−1 for the oak were evaluated from the variation in the water storage in the stem and the difference of water potential between root and stem. Evaluations of the water budget were made for each test stand. The results indicated that the contribution of water storage in the stem to transpiration accounted for 10 to 20% of the daily transpiration. Copyright © 2001 John Wiley & Sons, Ltd.
Strontium isotope constraint on the provenance of basic cations in soil water and stream water in the Kawakami volcanic watershed, central Japan
Authors: Nakano Takanori , Yokoo Yoriko , Yamanaka Masaru 
Published: September 2002

AbstractPositive correlations among the concentrations of Sr, Ca and Mg in soil water and stream water in a forested volcanic watershed at Kawakami, central Japan indicate that the Sr isotope can be used as a tool to elucidate the source and transport of the essential terrestrial ecosystem nutrients, Ca and Mg. The 87Sr/86Sr ratio in surface soil water varied widely along a 74 m slope; it was almost identical to the 87Sr/86Sr ratio of exchangeable soil and existing plants with different rooting zones (Japanese oak and bamboo grass), but differed significantly from that of soil minerals. In contrast, the 87Sr/86Sr ratios of stream water at baseflow periods were uniform regardless of location and time, and were indistinguishable from those of the weathered andesite bedrock. The Sr isotopic and elemental data indicate that Sr, Ca and possibly other cations (e.g. K, Mg) in the plant cycle efficiently with exchangeable soil through soil water and without a large supply of cations from secondary soil minerals, while cations in stream water are controlled mainly by exchange reactions with bedrock derived secondary minerals occurring in the lower soil horizon to water‐saturated zones. It is calculated that about 10% of Sr and Mg and 20% of Ca in stream water are derived from wet precipitation, while the contribution of atmospherically derived Sr and Ca in the exchangeable soil pool increases from 22 to 72% and from 42 to 87% respectively, with increasing distance from the valley. This increase of Sr and Ca in the exchangeable soil pool coincides with rock derived, low Ca materials dominating in the surface soil of the upper elevation in the slope. Copyright © 2001 John Wiley & Sons, Ltd.
Tests of CAPM with nonstationary beta
Authors: Huang Ho‐Chuan (river) 
Published: September 2002

AbstractConventional tests of capital asset pricing model usually assume that β, a measure of the systematic risk, is stable over time. Nonetheless, empirical investigations generally find that β tends to be volatile over time. This paper formulates novel empirical models for testing the capital asset pricing model (CAPM) by allowing β to be drawn from two distinct regimes, or to be time varying. The econometric method via the Gibbs sampler with data augmentation algorithm is applied to the data from Taiwan Stock Market to estimate and test the model. Copyright © 2001 John Wiley & Sons, Ltd.
Modelling fundamentals for forecasting capital flows to emerging markets
Authors: Mody Ashoka , Taylor Mark P. , Kim Jung Yeon 
Published: September 2002

AbstractIn this paper, we provide capital flow forecasts to 32 developing countries using a vector error correction framework based on underlying domestic (pull) fundamentals and international (push) factors. In general, pull factors have a heavier weight in determining these capital flows. However, short‐term dynamics of capital flows can be significantly influenced by external developments. Simulations under various economic scenarios show that while financial variables (such as the US interest rate and high‐yield spread) are important, real US activity may be even more potent in influencing capital flow movements. Copyright © 2001 John Wiley & Sons, Ltd.