bluuebunny/crossref_metadata_2025 huggingface dataset:
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

The 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

Most 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

Functional 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

In 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

Unusual 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

The 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

This 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

Current 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

To 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

Positive 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

Conventional 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

In 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.
Using dendronal signatures for feature extraction and retrieval
Authors: Chen Luojian , Berry Michael W. , Hargrove William W.
Published: September 2002

A dendrone is a hierarchical thresholding structure that can be automatically generated from a complex image. The dendrone structure captures the connectedness of objects and subobjects during successive brightness thresholding. Based on connectedness and changes in intensity contours, dendronic representations of objects in images capture the coarse‐to‐fine unfolding of finer and finer detail, creating a unique signature for target objects that is invariant to lighting, scale, and placement of the object within the image. Subdendrones within the hierarchy are recognizable as objects within the picture. Complex composite images can be autonomously analyzed to determine if they contain the unique dendronic signatures of particular target objects of interest. In this paper, we describe the initial design of the dendronic image characterization environment (DICE) for the generation of dendronic signatures from complex multiband remote imagery. By comparing subdendrones within an image to dendronic signatures of target objects of interest, DICE can be used to match/retrieve target features from a library of composite images. The DICE framework can organize and support a number of alternative object recognition and comparison techniques, depending on the application domain. © 2001 John Wiley & Sons, Inc. Int J Imaging Syst Technol 11, 243–253, 2000
Hemocompatibility, biocompatibility, inflammatory and in vivo studies of primary reference materials low‐density polyethylene and polydimethylsiloxane: A review
Authors: Bélanger Marie–Claire , Marois Yves
Published: September 2002

In 1984, low‐density polyethylene (LDPE) and polymethylsiloxane (PDMS), two primary reference materials (PRM), were made available by the National Heart, Lung, and Blood Institute (NHLBI) as discriminatory tools for the validation of standardized and novel in vitro and in vivo tests in the evaluation of biomaterials. This article reviews the results and conclusions obtained by several studies investigating the hemocompatibility, in vitro biocompatibility, inflammatory response, and in vivo tissue reactions of these two reference materials. Variable results obtained with LDPE and PDMS in ex vivo hemocompatibility studies were attributed to the type of animal model used, the flow velocity of the circulating blood, the time of exposure, and the methodology used to measure blood cell adhesion or activation at the surface of the materials. In contrast, both the LDPE and PDMS appeared to be suitable reference materials when used in in vitro biocompatibility, inflammatory response, and in vivo studies. However, caution must be taken when interpreting the results, because gamma sterilization of these two materials as well as their origin (for example PDMS) are two critically important factors. In conclusion, we see a definite need for standardized hemocompatible parameters and better high‐quality hemocompatibility studies on PRM. This review also suggests other materials as potential PRM candidates, namely, Biomer® and Intramedic™ polyethylene. © 2001 John Wiley & Sons, Inc. J Biomed Mater Res (Appl Biomater) 58: 467–477, 2001
Acrolein induces activation of the epidermal growth factor receptor of human keratinocytes for cell death
Authors: Takeuchi Kei , Kato Masashi , Suzuki Haruhiko , Akhand Anwarul A. , Wu Jianghong , Hossain Khaled , Miyata Toshio , Matsumoto Yoshinari , Nimura Yuji , Nakashima Izumi
Published: September 2002

Acrolein, which is a highly reactive formaldehyde generated by lipid peroxidation, can affect skin and cause various disorders. The effect of exposure of human keratinocytes to acrolein on cell surface‐oriented signal transduction into cells was examined. Incubation of human keratinocytes with a relatively low concentration (50 μM) of acrolein caused a prompt and selective induction of tyrosine phosphorylation of the epidermal growth factor receptor (EGFR) as a 180‐kDa molecule during the period from 5–30 min after the start of incubation. This early event was followed by an increase in the density and number of phosphotyrosine‐containing proteins during the period from 60–120 min after the start of incubation. The catalytic activity of EGFR as measured by the levels of autophorphorylation and phosphorylation of an exogenously added substrate, casein, in in vitro kinase assay, greatly increased as early as 1 min after the start of incubation and then decreased gradually 30 min later. MAP family kinases, including ERK, JNK, and p38 kinase, and the potentially downstream transcription factor c‐Jun were all promoted for phosphorylation/activation during a period of 5–30 min. Selective prompt phosphorylation/activation of EGFR followed by phosphorylation of MAP family kinases and c‐Jun and their blockade by a specific EGFR inhibitor, AG1478, suggested that activation of EGFR is the major, and possibly single, cell surface element for intracellular signal transduction in acrolein‐treated cells. Incubation of human keratinocytes with 50 μM of acrolein induced atypical apoptosis with morphologic apoptotic features with low‐grade oligonucleoside‐sized DNA fragmentation. Partial inhibition of such a cytopathic effect of acrolein on human keratinocytes by preincubation with AG1478 suggests the involvement of an EGFR‐mediated signal pathway for atypical apoptosis. These results provide new information on acrolein‐induced cell surface‐oriented signal transduction to human keratinocytes, and this information may be useful for understanding the pathogenesis of a number of skin diseases in response to environmental acrolein and acrolein‐generating ultraviolet irradiation. J. Cell. Biochem. 81: 679–688, 2001. © 2001 Wiley‐Liss, Inc.
Vertex criticality for upper domination and irredundance
Authors: Grobler P. J. P. , Mynhardt C. M.
Published: September 2002

Let π be any of the domination parameters ir γ, i, β, Γ or IR. The graph G is π‐critical (π+‐critical) if the removal of any vertex of G causes π(G) to decrease (increase). We show that the classes of IR‐critical and Γ‐critical graphs coincide, and exhibit a class of Γ+‐critical graphs. © 2001 John Wiley & Sons, Inc. J Graph Theory 37: 205–212, 2001
Mispatterning in the ommatidia of Apis mellifera pupae treated with a juvenile hormone analogue
Authors: Boleli Isabel Cristina , Bitondi Márcia Maria Gentile , Figueiredo Vera Lúcia Castelo , Simões Zilá Luz Paulino
Published: September 2002

To further understand the function of morphogenetic hormones in honeybee eye differentiation, the alterations in ommatidial patterning induced by pyriproxyfen, a juvenile hormone (JH) analogue, were studied by scanning and transmission electron microscopy. Prepupae of prospective honeybee workers were treated with pyriproxyfen and the effects on ommatidial differentiation were described at the end of the pupal development. The results show that the entire ommatidia, i.e., the dioptric as well as the receptor systems, were affected by the JH analogue. The wave of ommatidial differentiation, which progresses from the posterior to the anterior region of the pupal eyes, was arrested. In treated pupae, the rhabdomeres only differentiated at the apical axis of the retinula, the secondary and tertiary pigment cells did not develop their cytoplasm protrusions, and the cone cell quartet did not pattern correctly. Simultaneously, an intense vacuolization was observed in cells forming ommatidia. In a previous study we showed that pyriproxyfen exerts an inhibition on pupal ecdysteroid secretion. In this sense, the arrested ommatidial differentiation in pyriproxyfen‐treated pupae could be due to a secondary effect resulting from an alteration in pupal ecdysteroid titers. J. Morphol. 249:89–99, 2001. © 2001 Wiley‐Liss, Inc.
Managing relationship conflict and the effectiveness of organizational teams
Authors: De Dreu Carsten K.W. , Van Vianen Annelies E.M.
Published: September 2002

Past research has revealed that team effectiveness and satisfaction suffer when teams experience relationship conflict—conflict related to interpersonal issues, political norms and values, and personal taste. This study examined how teams should respond to these conflicts. Three types of conflict responses were studied: collaborating responses, contending responses, and avoiding responses. A field study involving a heterogeneous sample of teams performing complex, non‐routine task showed that collaborating and contending responses to relationship conflict negatively relate to team functioning (i.e., voice, compliance, helping behavior) and overall team effectiveness, while avoiding responses were associated with high team functioning and effectiveness. It is suggested that collaborating and contending responses to relationship conflict distract team members from their tasks, while avoiding responses appear more functional in that they allow team members to pursue task performance. Copyright © 2001 John Wiley & Sons, Ltd.
Homogeneity adjustments of temperature and precipitation series—Finnish and Nordic data
Authors: Tuomenvirta H.
Published: September 2002

An analysis is made of the adjustments needed to produce three homogeneous data sets, namely the 1961–1990 mean temperatures in Finland, the North Atlantic Climatolological Dataset (NACD) temperature and precipitation series (1890–1990), and the Finnish daily mean maximum and minimum temperature series (1910–1995), as well as the reasons for making such adjustments. The adjustments in the annual (seasonal) mean temperatures are up to ±1°C (±2°C), and annual precipitation adjustments can be ±40%. In Finland, the homogeneity breaks in the normal period temperatures and in the long‐term daily mean maximum and minimum temperatures appear to be random, and thus, do not bias averages based on large numbers of stations. However, both the temperature and precipitation series of the NACD would have been statistically significantly biased without adjustments. Station relocations appear to be the most common cause of homogeneity breaks in the temperature series. In the NACD, the adjustments resulting from relocations are statistically significant and reflect changes to colder observing sites. Also, changes in the formula used for the calculation of mean temperatures and urbanization both cause systematic biases in the data. The installation of improved precipitation gauges has been systematic in the NACD; thus, the original series need to be adjusted upwards in the early years. The applied adjustments are of the same order of magnitude as the observed long‐term trends, which stresses the importance of the testing and adjusting of long‐term series before analysis of climatic changes. In order to monitor climatic changes in a reliable manner, the observing network should be designed to withstand the common discontinuities (e.g. relocations, observer and environment changes etc.) in observation series, because the number of homogeneity breaks appears to be roughly constant in time. Moreover, the introduction of new technology may cause systematic changes in the observations, and comprehensive comparison measurements are needed. Copyright © 2001 Royal Meteorological Society
Climatology of near‐surface wind patterns over Switzerland
Authors: Weber Rudolf O. , Furger Markus
Published: September 2002

Over complex, mountainous terrain the near‐surface winds can form intricate patterns as large‐scale winds and locally forced wind systems interplay. Switzerland, with its mountainous topography and dense meteorological network of 115 automated surface stations, ideally serves as a study area for such wind system interactions. Applying an automated classification scheme to the wind data of one single year (1995), 16 distinct near‐surface flow patterns were found. These patterns also show characteristic distributions in magnitude and areal extent of temperature, global radiation and precipitation. An 18‐year climatology of flow patterns was created with an identification method for fewer stations. This allowed the determination of annual and diurnal variations in the frequencies of occurrence of the different flow patterns, revealing pronounced daytime and night‐time classes characterized by thermally forced winds. Transition probabilities between the flow patterns were computed as well. The relationship between the near‐surface wind patterns and the synoptic flow situation was investigated with a comparison with synoptic weather types defined for the Alpine region. The results show clear but not unequivocal interdependencies between the synoptic weather type and the near‐surface flow pattern. Copyright © 2001 Royal Meteorological Society
Markov chain models for pre‐monsoon season thunderstorms over Pune
Authors: Kulkarni M. K. , Kandalgaonkar S. S. , Tinmaker M. I. R. , Nath Asha
Published: September 2002

The probabilistic distribution of the thunderstorm phenomenon during the pre‐monsoon season (1 March to 18 June) over Pune, a tropical Indian station, has been examined with the help of Markov chain models using daily thunderstorm data for a period of 11 years (1970–80). The data have also been tested using Akaike's information criterion. This test has clearly indicated that the first‐order Markov chain model is the best fit model for thunderstorm forecasting, which has described the appropriate period (8 days) of occurrence of thunderstorm phenomenon over Pune. Further, the steady‐state probabilities and mean recurrence time of thunderstorm days and non‐thunderstorm days have also been calculated for the first‐ and second‐order Markov chain models. These computations have revealed that the observed and theoretical values of steady‐state probabilities are realistically matched. Copyright © 2002 Royal Meteorological Society.
Recent trends in temperature and precipitation over South Korea
Authors: Jung Hyun‐Sook , Choi Youngeun , Oh Jai‐Ho , Lim Gyu‐Ho
Published: September 2002

Temperature and precipitation changes over South Korea have been studied since 1954, both in terms of means and extreme events, using observational station data. Recurrence intervals are defined to examine trends in extreme events at each station. Generally, it is possible to describe trends in temperature and precipitation over South Korea as follows. The annual mean temperature shows an upward trend at a rate of 0.23 °C decade−1 in the past four to five decades. There are some indications that climatic extremes have increased during recent decades. The diurnal temperature range increased in the later part of the time series (except for summer) as a result of a faster increase in maximum temperature than in minimum temperature. This is not consistent with the results reported elsewhere in the world. A wavelet analysis of wintertime temperatures indicates that the rapid warming in the recent decade may be associated with the warm phase of a decadal–interdecadal variation. The frequency of occurrence of extreme maximum temperature events shows an increasing trend, with higher values in the 1980s and 1990s. The frequency of occurrence of extreme minimum temperature events shows the opposite, with a statistically significant decreasing trend. Copyright © 2002 Royal Meteorological Society.
Relationship between Soviet snow and Korean rainfall
Authors: Kripalani R. H. , Kim Baek‐Jo , Oh Jai‐Ho , Moon Sung‐Euii
Published: September 2002

In this study the statistical relationship between winter–spring Soviet snow depth and summer monsoon rainfall over South Korea has been investigated by lag correlation coefficients and composite analysis. Data for the 1966–95 period are used. Results reveal that the winter/springtime snow depth over western Eurasia (over Kazakhstan) is negatively related, whereas the snow depth over eastern Eurasia (over Manchuria–eastern Siberia) is positively related with Korean monsoon rainfall. The dipole correlation pattern suggests that heavy snow over eastern Eurasia and light snow over western Eurasia is favourable, whereas the reverse situation is unfavourable for monsoon activity over South Korea. The NCEP–NCAR re‐analyses data reveal that the dipole correlation configuration is indicative of a mid‐latitude long‐wave pattern with an anomalous ridge over north Asia during the winter prior to a weak Korean monsoon and an anomalous trough prior to a strong monsoon. The re‐analyses data further suggest that the position, shape, and strength of the summertime North Pacific subtropical high and the low‐level jet over the East Asian sector could be considerably influenced by the snow distribution over Eurasia. Copyright © 2002 Royal Meteorological Society.
Multiple‐Well, multiple‐path unimolecular reaction systems. I. MultiWell computer program suite
Authors: Barker John R.
Published: September 2002

Unimolecular reaction systems in which multiple isomers undergo simultaneous reactions via multiple decomposition reactions and multiple isomerization reactions are of fundamental interest in chemical kinetics. The computer program suite described here can be used to treat such coupled systems, including the effects of collisional energy transfer (weak collisions). The program suite consists of MultiWell, which solves the internal energy master equation for complex unimolecular reactions systems; DenSum, which calculates sums and densities of states by an exact‐count method; MomInert, which calculates external principal moments of inertia and internal rotation reduced moments of inertia; and Thermo, which calculates equilibrium constants and other thermodynamics quantities. MultiWell utilizes a hybrid master equation approach, which performs like an energy‐grained master equation at low energies and a continuum master equation in the vibrational quasicontinuum. An adaptation of Gillespie's exact stochastic method is used for the solution. The codes are designed for ease of use. Details are presented of various methods for treating weak collisions with virtually any desired collision step‐size distribution and for utilizing RRKM theory for specific unimolecular rate constants. © 2001 John Wiley & Sons, Inc. Int J Chem Kinet 33: 232–245, 2001
Causal processes of soil salinization in Tunisia, Spain and Hungary
Authors: Schofield R. , Thomas D. S. G. , Kirkby M. J.
Published: September 2002

Soil salinization arises due to the build up of soluble salts at or near the soil surface. Salts accumulate by primary and secondary processes that alter the soils physicochemical properties and lead to direct and indirect soil degradation. Results are presented here from the study of three contrasting salt‐affected landscapes. The Chott el Fedjadj, Tunisia, is a naturally salt‐affected basin containing saline sediments deposited during a marine incursion. The endoreic conditions lead to salt recirculation, concentration and reprecipitation. In the Guadalentin Valley, Spain, increased irrigated agriculture has led to aquifer overexploitation releasing gas and salts. Irrigating with the resultant contaminated groundwater has induced soil salinization. The salt accumulation and translocation is dictated predominantly by irrigation method, water quality and quantity. Hungary has the largest expanse of naturally salt‐affected soil in Europe, with the dominant soil type being solonetz. In Hungary the type of salt‐affected soil development is related to the salts present, hydraulic properties of the soil and depth and quality of the watertable. In Tunisia a catenary relationship of increased water and soil salinity towards the centre of the chott is found, whereas in Spain the highest salinities were found under flood irrigation with the valley displaying a complex spatial distribution of soil salinity. The sediment distribution in Hungary dictates that solonchak soils are found mostly in the Danube–Tisza interfluve and solonetz soils in the Tisza floodplain, with localized variations in soil type related to watertable characteristics. Copyright © 2001 John Wiley & Sons, Ltd.
A conceptual framework for analyzing deception and debriefing effects in marketing research
Authors: Toy Dan , Wright Lauren , Olson Jerry
Published: September 2002

Deception and debriefing are commonly used marketing research procedures. However, marketers have paid little attention to the ethical and methodological issues inherent in the use of these practices. One explanation may be that greater emphasis has traditionally been placed on research outcomes than on how the research results were generated. In this article we attempt to redress this situation by examining the methodological and ethical issues concerning deception and debriefing from a process perspective. We review the past research on deception and debriefing, identify key psychological processes by which deception and debriefing influence participants, and present a framework for understanding the effects of both deceptions and debriefings on research participants. We then show how the results generated from this framework can be examined from an ethical perspective to provide a better understanding of the benefits and costs of the research to all stakeholders. © 2001 John Wiley & Sons, Inc.
Non‐vital, prosthetic, and virtual reality models of microsurgical training
Authors: Lannon Declan A. , Atkins Jo‐Anne , Butler Peter E.M.
Published: September 2002

Many microsurgical training models exist. These can be broadly classified into living and non‐living. The latter type can be further sub‐classified into non‐vital, prosthetic, and virtual reality models. We review each model within these sub‐groups with reference to the ideal properties of a training model. The most important attribute of any model is that the skills acquired from it must translate efficiently into microsurgical skill in the clinical situation. We believe that non‐vital and prosthetic models are an important complement to living ones in training and maintaining the skills of all microsurgeons. As virtual reality technology improves, virtual models may succeed the rat as the microsurgical training tool of choice. © 2001 Wiley‐Liss, Inc. MICROSURGERY 21:389‐393 2001
Effect of hypothermia on the ischemic and reperfused rat skeletal muscle, monitored by in vivo 31p‐magnetic resonance spectroscopy
Authors: Lundberg Jonas , Elander Anna , Soussi Bassam
Published: September 2002

The aim of this study was to compare the ischemic and postischemic energetic changes of rat skeletal muscle in response to hypothermia or room temperature, monitored noninvasively and continuously by in vivo 31P‐magnetic resonance spectroscopy (31P‐MRS). A model of pedicled rat rectus femoris muscle was developed and analyzed by in vivo 31P‐MRS at a magnetic field strength of 2.35 T. Measurements were performed at three time points: before ischemia, after 4 hours of ischemia, and after 1 hour of reperfusion. Three groups were studied: (1) sham‐operated rats (n = 6); (2) rats subjected to room temperature (24–26°C, n = 6); and (3) rats subjected to hypothermia (9–12°C, n = 6). Blood perfusion was measured by laser Doppler flowmetry (LDF). In the hypothermic group, phosphocreatine (PCr) recovered to 75% and adenosine triphosphate (ATP) to 86%; in the room temperature group, the recovery was 53% and 51%, respectively (P < 0.05). Skeletal muscle subjected to hypothermia (9–12°C) was found to recover to a higher postischemic energetic level compared with skeletal muscle subjected to room temperature. Hypothermia appears to be a simple and eFFective method with which to reduce the damage related to ischemia and reperfusion. © 2001 Wiley‐Liss, Inc. MICROSURGERY 21:‐‐ 2001
Optimization of energetic advantages of burst swimming of fish
Authors: Stöcker Sabine , Weihs Daniel
Published: September 2002

It is well‐known that fish can swim more efficiently by alternating periods of accelerated motion and powerless gliding. It has been shown numerically that this strategy is most effective for small velocities and very small variations of the accelerating and gliding mode. In the paper presented here, this has been reinvestigated analytically. By that means, the maximum energy saving obtained can be evaluated. Knowing the cheapest swimming mode in terms of energy of fish enables knowing its minimal oxygen need. In calculating the volume a fish crosses using this cheapest mode, we are able to estimate the least required oxygen concentration of the surrounding water. Therefore, we can also calculate the restriction on the size of fish schools due to oxygen limitations. The theoretical value for the maximum size of a school increases if one considers energetic advantages of schooling. These evaluations are of special interest for the estimation of fish stocks and for fishery. Copyright 2001 John Wiley & Sons, Ltd.
Control of the impedance bandwidth of wideband planar monopole antennas using a beveling technique
Authors: Ammann M. J.
Published: September 2002

Wideband planar monopole antennas have recently been proposed for use on digital mobile terminals. The square planar monopole is the simplest to analyze, and suffers little degradation of radiation pattern within the impedance bandwidth. The addition of a bevel on one or both sides of the feed probe is shown to increase the bandwidth with good control of the upper edge frequency. The impedance bandwidth ratio for this antenna is shown to vary from 2:1 to 6:1, which can be controlled by beveling the planar geometry. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 30: 229–232, 2001.
Plasma levels of natriuretic peptides in relation to doxorubicin‐induced cardiotoxicity and cardiac function in children with cancer
Authors: Hayakawa H. , Komada Y. , Hirayama M. , Hori H. , Ito M. , Sakurai M.
Published: September 2002

Background

Anthracyclines are effective anticancer drugs for childhood cancer with dose‐limiting cardiotoxicity. Children who have received anthracyclines thus need periodical cardiac evaluation. The plasma levels of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) have been shown to increase in proportion to severity of cardiac dysfunction. We examined whether plasma levels of ANP and BNP, in addition to echocardiographic evaluation, can be used as specific markers for doxorubicin‐induced cardiotoxic effects in children.

Procedure

Consecutively, 34 patients (18 boys and 16 girls) who had previously received doxorubicin‐containing chemotherapy were enrolled in this study. Plasma ANP and BNP were assayed simultaneously at the time of first cardiac function evaluation by echocardiography.

Results

Of the 34 patients, 8 (23.5%) had left ventricular dysfunction as assessed by echocardiography. Both ANP and BNP plasma levels in these patients were significantly elevated in comparison with healthy controls (P < 0.01) or patients with normal cardiac function (P < 0.05). It should be also noted that ANP and BNP levels were correlated significantly with cardiac systolic function, but not with diastolic function.

Conclusions

These results suggest that plasma ANP and BNP levels could be markers for doxorubicin‐induced cardiotoxicity in children. Measurement of natriuretic peptide levels during treatment may allow earlier‐identification of individuals at risk for severe cardiac damage. Med. Pediatr. Oncol. 37:4–9, 2001. © 2001 Wiley‐Liss, Inc.
Primary Ewing tumor of the vertebrae: Clinical characteristics, prognostic factors, and outcome*
Authors: Venkateswaran Lakshmi , Rodriguez‐Galindo Carlos , Merchant Thomas E. , Poquette Catherine A. , Rao Bhaskar N. , Pappo Alberto S.
Published: September 2002

Background

Fewer than 10% of Ewing family of tumors (EFT) arise in the vertebrae. Little information is available regarding the clinical presentation and outcome of these tumors.

Procedure

We reviewed the clinical features, prognostic factors, and outcome of EFT of the spine identified at our institution between 1962 and 1999.

Results

Thirty‐three (10%) of 344 patients with EFT had a primary vertebral tumor. There were 21 (64%) males. Median age at diagnosis was 13.3 years. Six patients had metastatic disease and 10 had tumors  ≥ 8 cm in diameter. Primary sites were sacral (13), thoracic (10), lumbar (8), and cervical (2) vertebrae. We found no association between the affected spinal region and outcome, although sacral tumors were associated with delayed diagnosis (4 vs. 2 months after onset of symptoms, P = 0.076). Pain (n = 32) and neurologic deficits (n = 31; 82% motor, 58% sensory, 42% bladder, 27% bowel) were the most common presenting features. All patients received combination chemotherapy and local radiotherapy. With a median follow up of 9.7 years, 5‐year survival and event‐free survival ( ± SD) estimates were 48.1% (8.9%) and 35.6% (8.6%), respectively, comparable to those of other patients with EFT. Outcome was better for patients with tumor size  < 8 cm (P = 0.008) or localized disease (P = 0.084). Treatment era and specific tumor site did not affect outcome.

Conclusions

Outcomes are similar for primary EFT of the spine and primary EFT in other sites. Unlike others, we found that patients with sacral tumors did not fare worse than patients with tumors at other spinal sites. Med. Pediatr. Oncol. 37:30–35, 2001. © 2001 Wiley‐Liss, Inc.
Pancreatoblastoma in childhood: Clinical course and therapeutic management of seven patients
Authors: Défachelles A.S. , Martin de Lassalle E. , Boutard P. , Nelken B. , Schneider P. , Patte C.
Published: September 2002

Background

To analyze the clinical course of pancreatoblastoma in children and to propose management and therapy.

Procedure

Retrospective review of seven cases of pancreatoblastoma treated in France over a 20‐year period and literature review.

Results

Median age of patients was 6 years. The tumor was well encapsulated in one patient and had direct extension to adjacent tissues in two others. Three patients had regional lymph node involvement and one had liver metastases. The tumor arose in the head of the pancreas in three children, in the tail and body in two and in the tail and in the body, one each. Elevation of AFP serum levels was noted in four out of 6 cases. Five tumor resections were performed, one initially and 4 after neoadjuvant chemotherapy, and cisplatin plus doxorubicin seemed effective. Two chidren received post‐operative irradiation because of incomplete resection. In all, four children are disease free with a median follow‐up of 50 months ( range, 5–120 months) : one had a complete removal of tumor at diagnosis and no further treatment, three had unresectable tumor at diagnosis and received neoadjuvant chemotherapy with cisplatin and doxorubicin. One of them also received post‐operative irradiation.

Conclusions

Pancreatoblastoma is a curable tumor. Examination of serum AFP levels may be useful for diagnosis and to follow the course of the disease. Complete resection is the treatment of choice. However, tumor is often unresectable at diagnosis and preoperative chemotherapy is needed to reduce tumor volume. We suggest a regimen that include cisplatin and doxorubicin. In patients with incompletely resected disease, postoperative radiation may be indicated. Med. Pediatr. Oncol. 37:47–52, 2001. © 2001 Wiley‐Liss, Inc.