bluuebunny/crossref_metadata_2025_split huggingface dataset:
Genetic programming model for forecast of short and noisy data
Authors: Sivapragasam C. , Vincent P. , Vasudevan G. 
Published: August 2006

AbstractThough forecasting of river flow has received a great deal of attention from engineers and researchers throughout the world, this still continues to be a challenging task owing to the complexity of the process. In the last decade or so, artificial neural networks (ANNs) have been widely applied, and their ability to model complex phenomena has been clearly demonstrated. However, the success of ANNs depends very crucially on having representative records of sufficient length. Further, the forecast accuracy decreases rapidly with an increase in the forecast horizon. In this study, the use of the Darwinian theory‐based recent evolutionary technique of genetic programming (GP) is suggested to forecast fortnightly flow up to 4‐lead. It is demonstrated that short lead predictions can be significantly improved from a short and noisy time series if the stochastic (noise) component is appropriately filtered out. The deterministic component can then be easily modelled. Further, only the immediate antecedent exogenous and/or non‐exogenous inputs can be assumed to control the process. With an increase in the forecast horizon, the stochastic components also play an important role in the forecast, besides the inherent difficulty in ascertaining the appropriate input variables which can be assumed to govern the underlying process. GP is found to be an efficient tool to identify the most appropriate input variables to achieve reasonable prediction accuracy for higher lead‐period forecasts. A comparison with ANNs suggests that though there is no significant difference in the prediction accuracy, GP does offer some unique advantages. Copyright © 2006 John Wiley & Sons, Ltd.
Seasonal flooding in Bangladesh – variability and predictability
Authors: Chowdhury Md. Rashed , Ward M. Neil 
Published: August 2006

AbstractAt present, Bangladesh has a flood forecasting lead time of only 3 days or so. There is demand for a forecasting lead time of a month to a season. The primary objectives of this paper are to study the variability and predictability of seasonal flooding in Bangladesh, as revealed by large‐scale predictors of the climate across the watersheds. To explore the source of predictability, accessible Bangladesh hydrological indicators are related to large‐scale oceanic variability and to large‐scale atmospheric circulation patterns predicted by general circulation models (GCMs).Correlation analyses between the flood‐affected area (FAA) for July–September and tropical sea‐surface temperature (SST) indicate connections to tropical Pacific and Indian Ocean SSTs, at a short lead time of a month or so. These are related to El Niño–southern oscillation (ENSO). Correlations between the SSTs of the preceding October–December and the July–September FAA are weaker but notable. Forecasts of the FAA using the leading principal components (PCs) of SST were made, which provided good skill with a lead time of a month or so. The streamflows and rainfall observed in Bangladesh have been added to these prediction models. Finally, the SST PCs were replaced with PCs of GCM prediction fields (precipitation). The prediction models at short lead time that were constructed for FAA were of generally similar levels of skill to that for SST. This is encouraging, as it suggests that linkages with SST can be successfully recovered in a physical model of the climate system in Bangladesh.This study concludes that seasonal flood prediction in Bangladesh is possible from the unusually warm or cold SST in parts of the tropics. This predictability can be enhanced with the information achievable from monitoring the downstream streamflows (which are generated mainly from upstream rainfall conditions) in advance of the flooding season. Finally, this study recommends formalizing a regional cooperation among the countries in the principal co‐basin areas of the Ganges–Brahmaputra–Meghna to achieve this goal. Copyright © 2006 John Wiley & Sons, Ltd.
Assessment of rainfall‐runoff models based upon wavelet analysis
Authors: Lane Stuart N. 
Published: August 2006

AbstractA basic hypothesis is proposed: given that wavelet‐based analysis has been used to interpret runoff time‐series, it may be extended to evaluation of rainfall‐runoff model results. Conventional objective functions make certain assumptions about the data series to which they are applied (e.g. uncorrelated error, homoscedasticity). The difficulty that objective functions have in distinguishing between different realizations of the same model, or different models of the same system, is that they may have contributed in part to the occurrence of model equifinality. Of particular concern is the fact that the error present in a rainfall‐runoff model may be time dependent, requiring some form of time localization in both identification of error and derivation of global objective functions. We explore the use of a complex Gaussian (order 2) wavelet to describe: (1) a measured hydrograph; (2) the same hydrograph with different simulated errors introduced; and (3) model predictions of the same hydrograph based upon a modified form of TOPMODEL. The analysis of results was based upon: (a) differences in wavelet power (the wavelet power error) between the measured hydrograph and both the simulated error and modelled hydrographs; and (b) the wavelet phase. Power difference and wavelet phase were used to develop two objective functions, RMSE(power) and RMS(phase), which were shown to distinguish between simulated errors and model predictions with similar values of the commonly adopted Nash‐Sutcliffe efficiency index. These objective functions suffer because they do not retain time, frequency or time‐frequency localization. Consideration of wavelet power spectra and time‐ and frequency‐integrated power spectra shows that the impacts of different types of simulated error can be seen through retention of some localization, especially in relation to when and the scale over which error was manifest. Theoretical objections to the use of wavelet analysis for this type of application are noted, especially in relation to the dependence of findings upon the wavelet chosen. However, it is argued that the benefits of localization and the qualitatively low sensitivity of wavelet power and phase to wavelet choice are sufficient to warrant further exploration of wavelet‐based approaches to rainfall‐runoff model evaluation. Copyright © 2006 John Wiley & Sons, Ltd.
Novel “plum pudding” gels as potential drug‐eluting stent coatings: Controlled release of fluvastatin
Authors: McGillicuddy F.C. , Lynch I. , Rochev Y.A. , Burke M. , Dawson K.A. , Gallagher W.M. , Keenan A.K. 
Published: August 2006

AbstractThis study evaluated novel structural motifs known as “plum pudding” gels as potential drug‐eluting stent coatings. Controlled delivery of a HMG‐CoA reductase inhibitor (statin) from the intravascular stent surface represents a potential therapeutic modality for prevention of in‐stent restenosis (ISR). In this study, gels were comprised of fluvastatin‐loaded thermoresponsive microgel particles containing the relatively hydrophilic N‐isopropylacrylamide (NiPAAm), mixed with the more hydrophobic N‐tert‐butylacrylamide (NtBAAm) in different wt/wt ratios: 85/15, 65/35, and 50/50, randomly dispersed in a 65/35 or 85/15 NiPAAm/NtBAAm copolymer matrix. Fluvastatin release from 5 μm copolymer films was greatest from the most hydrophilic systems and least from the more hydrophobic systems. Release from hydrophobic matrices appeared to be via Fickian diffusion, enabling use of the Stokes–Einstein equation to determine diffusion coefficients. Release from hydrophilic matrices was non‐Fickian. Eluted drug retained its bioactivity, assessed as selective inhibition of human coronary artery smooth muscle cell proliferation. When stainless steel stent wires were coated (25 μm thickness) with fluvastatin‐loaded 65/35 microgels in an 85/15 copolymer matrix, drug elution into static and perfused flow environments followed similar elution profiles. In contrast to elution from copolymer films cast on flat surfaces, diffusion from stent wires coated with hydrophilic and hydrophobic systems both followed Fickian patterns, with slightly larger diffusion coefficients for elution from the flow system. We conclude that manipulation of the relative hydrophobicities of both microgel and matrix components of “plum pudding” gels results in tightly regulated release of fluvastatin over an extended time period relevant to initiation and propagation of ISR. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
Synthesis and temperature response analysis of magnetic‐hydrogel nanocomposites
Authors: Frimpong Reynolds A. , Fraser Stew , Zach Hilt J. 
Published: August 2006

AbstractMagnetically responsive hydrogel networks based on composites of magnetic nanoparticles and temperature responsive hydrogels were developed. These systems show great promise as active components of microscale and nanoscale devices and are expected to have a wide applicability in various biomedical applications. Specifically, nanocomposite hydrogel systems based on the temperature sensitive N‐isopropylacrylamide hydrogels crosslinked with ethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, and poly(ethylene glycol) 400 dimethacrylate (PEG400DMA) were synthesized and characterized. The composite systems were synthesized by UV free‐radical polymerization. Iron oxide magnetic nanoparticles were incorporated into the hydrogel systems by polymerizing mixtures of the nanoparticles and monomer solutions. The swelling response of these composite systems to different crosslinking molecular weights, temperature, and the effect of the presence of the magnetic nanoparticles were examined. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2007
Femtosecond two‐photon high‐resolution 3D imaging, spatial‐volume rendering and microspectral characterization of immunolocalized MHC‐II and mLangerin/CD207 antigens in the mouse epidermis
Authors: Tirlapur Uday K. , Mulholland William J. , Bellhouse Brian J. , Kendall Mark , Cornhill J. Fredrick , Cui Zhanfeng 
Published: August 2006

AbstractLangerhans cells (LCs) play a sentinel role by initiating both adaptive and innate immune responses to antigens pertinent to the skin. With the discovery of various LCs markers including antibodies to major histocompatibility complex class II (MHC‐II) molecules and CD1a, intracellular presence of racket‐shaped “Birbeck granules,” and very recently Langerin/CD207, LCs can be readily distinguished from other subsets of dendritic cells. Femtosecond two‐photon laser scanning microscopy (TPLSM) in recent years has emerged as an alternative to the single photon‐excitation based confocal laser scanning microscope (CLSM), particularly for minimally‐invasive deep‐tissue 3D and 4D vital as well as nonvital biomedical imaging. We have recently combined high resolution two‐photon immunofluorescence (using anti MHC‐II and Langerin/CD207 antibodies) imaging with microspectroscopy and advanced image‐processing/volume‐rendering modalities. In this work, we demonstrate the use of this novel state‐of‐the‐art combinational approach to characterize the steady state 3D organization and spectral features of the mouse epidermis, particularly to identify the spatial distribution of LCs. Our findings provide unequivocal direct evidence that, in the mouse epidermis, the MHC‐II and mLangerin/CD207 antigens do indeed manifest a high degree of colocalization around the nucleus of the LCs, while in the distal dendritic processes, mLangerin/CD207 antigens are rather sparsely distributed as punctuate structures. This unique possibility to simultaneously visualize high resolution 3D‐resolved spatial distributions of two different immuno‐reactive antigens, namely MHC‐II and mLangerin/CD207, along with the nuclei of LCs and the adjacent epidermal cells can find interesting applications. These could involve aspects associated with pragmatic analysis of the kinetics of LCs migration as a function of immuno‐dermatological responses during (1) human Immunodeficiency virus disease progression, (2) vaccination and targeted gene therapy, (3) skin transplantation/plastic surgery, (4) ultraviolet and other radiation exposure, (5) tissue‐engineering of 3D skin constructs, as well as in (6) cosmetic industry, to unravel the influence of cosmeceuticals. Microsc. Res. Tech., 2006. © 2006 Wiley‐Liss, Inc.
Intensity‐based signal separation algorithm for accurate quantification of clustered centrosomes in tissue sections
Authors: Fleisch Markus C. , Maxwell Christopher A. , Kuper Claudia K. , Brown Erika T. , Barcellos‐Hoff Mary Helen , Costes Sylvain V. 
Published: August 2006

AbstractCentrosomes are small organelles that organize the mitotic spindle during cell division and are also involved in cell shape and polarity. Within epithelial tumors, such as breast cancer, and some hematological tumors, centrosome abnormalities (CAs) are common, occur early in disease etiology, and correlate with chromosomal instability and disease stage. In situ quantification of CA by optical microscopy is hampered by overlap and clustering of these organelles, which appear as focal structures. CA has been frequently associated with Tp53 status in premalignant lesions and tumors. Here the authors described an approach to accurately quantify centrosome frequencies in tissue sections and tumors, independently of background or noise levels. Applying simple optical rules in nondeconvolved conventional 3D images of stained tissue sections, the authors showed that they could evaluate more accurately and rapidly centrosome frequencies than with traditional investigator‐based visual analysis or threshold‐based techniques. The resulting population‐based frequency of centrosomes per nucleus could then be used to approximate the proportion of cells with CA in that same population. This was done by taking into account baseline centrosome amplification and proliferation rates measured in the tissue. Using this technique, the authors showed that 20–30% of cells have amplified centrosomes in Tp53 null mammary tumors. Microsc. Res. Tech., 2006. © 2006 Wiley‐Liss, Inc.
Head and neck cancer cells are efficiently infected by Ad5/35 hybrid virus
Authors: Suominen Elina , Toivonen Raine , Grenman Reidar , Savontaus Mikko 
Published: August 2006

AbstractBackgroundClinical gene therapy trials using standard Ad5‐based vectors have thus far demonstrated limited efficacy, most likely due to low expression levels of adenoviral receptors on tumor cells. We sought to analyze adenoviral receptor expression levels on primary head and neck squamous cell carcinoma (HNSCC) cells and to determine whether adenoviral retargeting to the CD46 receptor via the Ad5/35 system would increase therapeutic potential for HNSCC.MethodsWe used flow cytometric analyses to determine adenoviral receptor expression levels on nine primary HNSCC cells collected from cancer patients. Adenoviruses Ad5.LacZ and Ad5/35.LacZ were used to analyze the differences in viral transduction both in vitro and in a HNSCC tumor mouse model.ResultsFlow cytometric analyses demonstrated uniformly high CD46 expression in all cells studied (85–99%). In contrast, coxsackievirus and adenovirus receptor (CAR) expression was substantially lower and highly variable (1.6–62%). αv integrin expression was between 39–98%. In situ stainings for β‐galactosidase gene expression demonstrated that Ad5/35.LacZ was clearly more effective than Ad5.LacZ in transducing primary HNSCC cells. Quantification of β‐galactosidase expression revealed up to 65 times higher transgene expression from Ad5/35.LacZ than Ad5.LacZ. In vivo, β‐galactosidase expression was detected in a substantial area after a single intratumoral injection of Ad5/35.LacZ, whereas injection with Ad5.LacZ resulted in gene expression only in a few cells.ConclusionsOur results demonstrate that the low and variable CAR expression levels limit the therapeutic efficacy of Ad5‐based strategies for HNSCC. In contrast, the effective in vivo transduction capacity of Ad5/35 warrants further development of this vector for the treatment of head and neck cancer. Copyright © 2006 John Wiley & Sons, Ltd.
Significance of the perfusion‐diffusion mismatch in chronic cerebral ischemia
Authors: Surikova Irina , Meisel Stefanie , Siebler Mario , Wittsack Hans‐Jörg , Seitz Rüdiger J. 
Published: August 2006

AbstractPurposeTo determine whether the perfusion deficit could predict brain infarction in patients with chronic cerebral ischemia who experienced recurring episodes of neurological symptoms and showed a perfusion‐diffusion mismatch on magnetic resonance (MR) images.Materials and MethodsIn 53 consecutive patients (38 males and 15 females, 62 ± 13 years old) with ischemia in the middle cerebral artery (MCA) territory, lesion volumetry was performed on parametric maps of the time‐to‐peak, the cerebral blood volume, and diffusion‐weighted (DW) images. The infarct lesions were assessed on follow‐up T2‐weighted (T2W) MR images after eight days. Cerebrovascular changes were determined by time‐of‐flight (TOF) MR angiography (MRA). Inferential and correlation statistics were used.ResultsPatients with chronic ischemic brain disease (N = 39) who presented with a severe perfusion‐diffusion mismatch in the presence of a normal cerebral blood volume had no or small brain infarctions as found on follow‐up T2W images. MRA revealed widespread abnormalities of the basal cerebral arteries compatible with brain perfusion abnormalities. In contrast, in acute stroke patients (N = 14) the deficit of cerebral perfusion predicted the infarct lesion in the T2W images.ConclusionOur results suggest that in chronic cerebral ischemia the normal blood volume was maintained despite the depression of cerebral perfusion and recurring minor insults. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
MR spectroscopy: Predicting long‐term neuropsychological outcome following pediatric TBI
Authors: Babikian Talin , Freier M. Catherin , Ashwal Stephen , Riggs Matt L. , Burley Todd , Holshouser Barbara A. 
Published: August 2006

AbstractPurposeTo identify useful acute indicators of long‐term neurocognitive outcome beyond clinical variables for children and adolescents treated for a traumatic brain injury (TBI).Materials and MethodsThe efficacy of magnetic resonance spectroscopy (MRS) acquired 6 ± 4 days after TBI in 20 children/adolescents in predicting intellectual and neuropsychological functioning one to four years post injury was assessed. Short echo‐time single voxel MRS (SVS) from normal‐appearing brain was compared to intermediate echo‐time multivoxel MR spectroscopic imaging (MRSI) from normal‐appearing and visibly‐injured brain acquired through the level of the corpus callosum (CC).ResultsN‐acetyl aspartate (NAA) was moderate to strongly correlated with cognitive scores. Mean NAA/creatine (Cre) from MRSI alone explained over 40% of the variance in cognitive scores and 18% of the variance above and beyond demographic and clinical variables alone. Mild to moderate associations were noted between SVS metabolites (glutamate/glutamine [Glx] and myoinositol [mI]) and cognitive scores, with no such associations apparent for choline (Cho) or Cre. Exploratory analyses revealed trends for regional neuroimaging data and specific cognitive abilities.ConclusionAcute MR spectroscopy of the pediatric brain injury patient improves prognostic ability and may provide valuable information for early treatment and intervention planning. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Desipramine prevents the sustained increase in corticotropin‐releasing hormone‐like immunoreactivity induced by repeated immobilization stress in the rat central extended amygdala
Authors: Santibañez Marcos , Gysling Katia , Forray María Inés 
Published: August 2006

AbstractClinical and experimental studies have shown that the activation of corticotropin‐releasing hormone (CRH) and noradrenergic systems mediate stress‐induced anxiety. Repeated immobilization stress (RIS) has been shown to induce long‐lasting anxiety behavior and changes in noradrenaline turnover. The present work was aimed at studying the effect of RIS on the in situ expression of CRH‐LI in the central extended amygdala and paraventricular nucleus of the hypothalamus (PVN). Our results showed that RIS for 15 days induces a significant increase of CRH‐LI expression in the central extended amygdala. The increase in CRH‐LI expression in the central extended amygdala was sustained even after a 25‐day stress‐free period. The concomitant administration of desipramine (DMI), a specific noradrenaline uptake inhibitor, fully prevented the RIS‐induced increase in CRH expression. RIS also induced an increase of CRH‐LI expression in the PVN that was prevented by the concomitant DMI administration. In contrast to the sustained effect observed in the central extended amygdala, the RIS‐induced increase of CRH‐LI expression in the PVN was nonlasting. DMI administration also prevented the RIS‐induced increase of adrenal gland weight. The present findings showing that RIS induces a sustained increase of CRH expression in the central extended amygdala suggest that the repeated activation of CRH neurons and CRH receptors in the central extended amygdala may underlie the long‐lasting anxiety behavior induced by RIS. Further studies should address the mechanisms involved in the effect of DMI and its eventual relevance in the therapeutic actions of DMI. © 2006 Wiley‐Liss, Inc.
Neuroprotective role of ERK1/2 and ERK5 in a dopaminergic cell line under basal conditions and in response to oxidative stress
Authors: Cavanaugh Jane E. , Jaumotte Juliann D. , Lakoski Joan M. , Zigmond Michael J. 
Published: August 2006

AbstractLoss of motor function in Parkinson's disease is due in part to degeneration of dopamine (DA) neurons. Pharmacological evidence suggests that the mitogen‐activated protein kinase signaling pathways involving extracellular signal‐regulated kinases (ERKs) play important roles in neuroprotection of DA neurons. However, the relative roles of the several ERK isoforms in the viability of DA neurons have not yet been determined. In the present study, we investigated the contributions of ERK5, as well as ERK1/2, to MN9D cell survival under basal conditions and in response to 6‐hydroxydopamine (6‐OHDA). We observed that U0126, an inhibitor of ERK activation, decreased basal survival of these cells. To differentiate between ERK1/2 and ERK5, cells were transfected with a dominant negative form of either ERK5 or MEK1, the upstream activator of ERK1/2. Transfection of MN9D cells with either dominant negative construct mimicked U0126, reducing cell survival. Moreover, transfection of the cells in such a way as to increase ERK5 or ERK1/2 activity inhibited 6‐OHDA‐induced cell death, although this effect was significant only in the case of ERK1/2 activation. These studies suggest that activations of ERK5 and ERK1/2 both promote basal DA cell survival and that ERK1/2 also protects DA cells from oxidative stress. These are the first studies to demonstrate a role for ERK5 in DA neuronal survival and to investigate the relative roles of ERK1/2 and ERK5 in basal DA survival and neuroprotection from oxidative stress. © 2006 Wiley‐Liss, Inc.