bluuebunny/crossref_metadata_2025_split huggingface dataset:
Can crude oils be distinguished by different component distribution obtained by laser desorption ionization mass spectrometry and evaluated by chemometrics?
Authors: Smaniotto Anna , Montanari Luciano , Flego Cristina , Rizzi Andrea , Ragazzi Eugenio , Seraglia Roberta , Traldi Pietro 
Published: April 2008

AbstractFourteen different crude oil samples were analyzed as collected by mass spectrometry. For two of them the results obtained by means of different techniques, i.e. electrospray ionization, atmospheric pressure chemical ionization, laser desorption/ionization, were compared. The latter technique leads to the best results: even if unable to give specific information on heteroatom‐containing components, it allows a general view to be obtained of the panorama of the oil composition in terms of molecular weight distribution. The statistical evaluation of the mass spectrometry data by multivariate techniques, such as cluster analysis (Average Linkage) and correspondence analysis, allows evidence for the differences and similarities among the crude oils under study. Copyright © 2008 John Wiley & Sons, Ltd.
Three‐dimensional ultrasound‐guided robotic needle placement: an experimental evaluation
Authors: Boctor Emad M. , Choti Michael A. , Burdette Everette C. , Webster III Robert J. 
Published: April 2008

AbstractBackgroundClinical use of image‐guided needle placement robots has lagged behind laboratory‐demonstrated robotic capability. Bridging this gap requires reliable and easy‐to‐use robotic systems.MethodsOur system for image‐guided needle placement requires only simple, low‐cost components and minimal, entirely off‐line calibration. It rapidly aligns needles to planned entry paths using 3D ultrasound (US) reconstructed from freehand 2D scans. We compare system accuracy against clinical standard manual needle placement.ResultsThe US‐guided robotic system is significantly more accurate than single manual insertions. When several manual withdrawals and reinsertions are allowed, accuracy becomes equivalent. Inex vivoexperiments, robotic repeatability was 1.56 mm, compared to 3.19 and 4.63 mm for two sets of manual insertions. In anin vivoexperiment with heartbeat and respiratory effects, robotic system accuracy was 5.5 mm.ConclusionsA 3D US‐guided robot can eliminate error bias and reduce invasiveness (the number of insertions required) compared to manual needle insertion. Remaining future challenges include target motion compensation. Copyright © 2008 John Wiley & Sons, Ltd.
Afferent influences on striatal development in organotypic cocultures
Authors: Snyder‐Keller Abigail , Tseng Kuei Y. , Lyng Gregory D. , Graber David J. , O'Donnell Patricio 
Published: April 2008

AbstractOrganotypic cocultures of striatum, cortex, and ventral mesencephalon were used to study the anatomical and physiological development of striatal neurons in the presence or absence of cortical and nigral (SN/VTA) inputs. Striatum and cortex were dissected from prenatal (E18–E22) or early postnatal (P0–P2) rats, and SN/VTA was dissected from E14–15 fetuses; pieces were maintained up to 3 weeks in static slice culture. Triple cocultures containing SN/VTA exhibited rapid and robust dopamine (DA) innervation of the striatum in a patchy pattern, and homogeneous distribution within the cortical piece, regardless of the orientations of the three pieces. DA fibers within the striatal piece overlapped striatal patch neurons, marked by DARPP‐32 immunoreactivity, in striatal cultures prepared from all age rats, but development most analogous to that seen in vivo was observed with the use of late prenatal (E20–E22) striatum. The patch/matrix organization was maintained in cultures prepared from late prenatal striatum in the presence of cortical and nigrostriatal DA afferents. In addition, a more complete transition to a patchy organization was observed in E18/19 striatal cultures in the presence of cortical and DA innervation. Electrophysiological recording demonstrated the presence of both spontaneous and cortically evoked activity in striatal medium spiny neurons; this activity was greatly influenced by the presence of DA innervation. These findings demonstrate the importance of afferent innervation in the maturation of striatal neurons in organotypic cultures. Synapse 62:487–500, 2008. © 2008 Wiley‐Liss, Inc.
Cerebellar modulation of frontal cortex dopamine efflux in mice: Relevance to autism and schizophrenia
Authors: Mittleman Guy , Goldowitz Daniel , Heck Detlef H. , Blaha Charles D. 
Published: April 2008

AbstractCerebellar and frontal cortical pathologies have been commonly reported in schizophrenia, autism, and other developmental disorders. Whether there is a relationship between prefrontal and cerebellar pathologies is unknown. Using fixed potential amperometry, dopamine (DA) efflux evoked by cerebellar or, dentate nucleus electrical stimulation (50 Hz, 200 μA) was recorded in prefrontal cortex of urethane anesthetized lurcher (Lc/+) mice with 100% loss of cerebellar Purkinje cells and wildtype (+/+) control mice. Cerebellar stimulation with 25 and 100 pulses evoked prefrontal cortex DA efflux in +/+ mice that persisted for 12 and 25 s poststimulation, respectively. In contrast, 25 pulse cerebellar stimulation failed to evoke prefrontal cortex DA efflux in Lc/+ mice indicating a dependency on cerebellar Purkinje cell outputs. Dentate nucleus stimulation (25 pulses) evoked a comparable but briefer (baseline recovery within 7 s) increase in prefrontal cortex DA efflux compared to similar cerebellar stimulation in +/+ mice. However, in Lc/+ mice 25 pulse dentate nucleus evoked prefrontal cortex DA efflux was attenuated by 60% with baseline recovery within 4 s suggesting that dentate nucleus outputs to prefrontal cortex remain partially functional. DA reuptake blockade enhanced 100 pulse stimulation evoked prefrontal cortex responses, while serotonin or norepinephrine reuptake blockade were without effect indicating the specificity of the amperometric recordings to DA. Results provide neurochemical evidence that the cerebellum can modulate DA efflux in the prefrontal cortex. Together, these findings may explain why cerebellar and frontal cortical pathologies co‐occur, and may provide a mechanism that accounts for the diversity of symptoms common to multiple developmental disorders. Synapse 62:544–550, 2008. © 2008 Wiley‐Liss, Inc.
Transmission power adjustment of wireless sensor networks using fuzzy control algorithm
Authors: Zhang Jianhui , Chen Jiming , Sun Youxian 
Published: April 2008

AbstractEnergy constraint is the most conspicuous characteristic in wireless sensor networks (WSN). Node deployment, dynamic topology control, and data transmission in WSN all consume a large amount of energy. Therefore, proper adjustment of transmission power (TP) contributes much energy saving. In this paper, a new TP adjustment method based on Fuzzy Control Theory, called FCTP, is proposed for the dynamic topology control. The simulation results show that this method is more robust to tolerate accidental interfere, more rapidly convergent, and more energy efficient than other TP adjustment approaches, which lead to longer network lifetime. Copyright © 2008 John Wiley & Sons, Ltd.
Overproduction of non‐translatable mRNA silences. The transcription of Ty1 retrotransposons in S. cerevisiae via functional inactivation of the nuclear cap‐binding complex and subsequent hyperstimulation of the TORC1 pathway
Authors: Wu Xiaofeng , Jiang Yi Wei 
Published: April 2008

AbstractCo‐suppression is high gene copy number‐triggered homology‐dependent gene silencing, and co‐suppression may have evolved in eukaryotes to counter invasive molecular parasites, such as viruses and transposons. We previously reported ‘Ty1 transcriptional co‐suppression’—high Ty1 copy number‐triggered transient transcriptional silencing of Ty1 retrotransposons in S. cerevisiae. We report here that this phenomenon is unlikely to be homology‐dependent, despite the copy number dependence. The Ty1 mRNA is an extremely poor template for translation, and overproduction of non‐translatable mRNA without Ty1 homology is sufficient to initiate the transient Ty1 transcriptional silencing. We present genetic evidence that overproduction of non‐translatable mRNA may functionally inactivate the nuclear cap‐binding complex (CBC), and inactivation of CBC may then hyperstimulate the TORC1 pathway to mediate Ty1 transcriptional silencing. Our results point to a potent regulatory function of non‐translatable mRNA in vivo (via CBC and TORC1) to potentially modulate a variety of intracellular activities, such as Ty1 transcription. Although overproduction of non‐translatable mRNA causes transient Ty1 transcriptional silencing, it does not play a detectable role in controlling Ty1 retrotransposition. Copyright © 2008 John Wiley & Sons, Ltd.
23S RNA‐derived replicon as a ‘molecular tag’ for monitoring inoculated wine yeast strains
Authors: Esteban Rosa , Rodríguez‐Cousiño Nieves 
Published: April 2008

AbstractIn this study we have developed a useful method to identify a particular yeast strain within a mixture of strains during must fermentation, based on the presence or absence of a stable genetic element derived from Saccharomyces cerevisiae 23S RNA autonomous replicon. 23S RNA is a natural virus‐like RNA replicon present in some S. cerevisiae strains, which encodes only its own RNA‐dependent RNA polymerase named p104. A modified version of 23S RNA (23S‐tagged RNA) was generated after transformation of S. cerevisiae wine strains with a launching plasmid, where six nucleotides were changed in the 23S RNA cDNA sequence without modifying the amino acid sequence of p104 RNA polymerase. Once generated, the 23S‐tagged RNA can replicate autonomously (without the plasmid), is very stable, is present in high copy number in stationary phase or nitrogen‐starved cells and confers no phenotype to the host, like the endogenous 23S RNA replicon. However, it can be distinguished from endogenous 23S RNA by reverse transcription followed by polymerase chain reaction (RT–PCR) with specific oligonucleotide primers. 23S RNA‐derived replicon can be used to tag wine yeast strains in order to monitor easily their prevalence over endogenous strains during wine fermentation. Copyright © 2008 John Wiley & Sons, Ltd.
Atomistic simulation of CeO2 surface hydroxylation: implications for glass polishing
Authors: Stanek Christopher R. , Tan Averyl H. H. , Owens Scott L. , Grimes Robin W. 
Published: April 2008

Abstract
Atomistic simulation techniques have been used to investigate the dissociative adsorption of water on the (110), (111), and (100) low index surfaces of CeO2, as well as a so-called “trench” surface configuration. Several different coverages of water have been considered to better understand how the hydroxylation process progresses. Hydroxylation energies and surface energies of CeO2 calculated via atomistic simulations are compared to similar results for other fluorite oxides. Finally, the modification of CeO2 crystallite morphology in the presence of water is predicted from the changes in surface energy and the implications of these morphological changes for glass polishing are discussed.
Nicotine dependence criteria and nicotine withdrawal symptoms in relation to pain among an adult general population sample
Authors: John Ulrich , Meyer Christian , Rumpf Hans‐Jürgen , Hapke Ulfert 
Published: April 2008

ABSTRACTBackground: Evidence has shown that people who have smoked at any point in life have a higher probability of pain than those who have never smoked. The goal of this study was to analyze whether there are associations between nicotine dependence including nicotine withdrawal with pain and the number of pain locations.Methods: Data stems from a cross‐sectional survey study with a probability sample of residents of a northern German area with 4075 study participants, aged 18–64 years (participation rate 70.2%). Face‐to‐face in‐home computer‐aided interviews (Composite International Diagnostic Interview) were used to assess single pain locations, the diagnostic criteria of nicotine dependence, alcohol dependence, depressive, and anxiety disorders according to the Diagnostic and Statistical manual of the American Psychiatric Association (DSM‐IV).Results: Ever smokers with three or more nicotine dependence criteria after controlling for alcohol dependence, depressive, anxiety disorders, age and gender revealed an odds ratio (OR) of 4.2 (95% confidence interval, CI, 2.0–9.0) compared to ever smokers without nicotine dependence criteria, and ever smokers with four or more nicotine withdrawal symptoms displayed an OR of 3.6 (CI 1.5–8.7) compared to ever smokers who had not experienced withdrawal symptoms. Current smokers who used 20 or more cigarettes per day had an OR of 0.5 (CI 0.3–0.8) of experiencing pain in three or more locations compared to former smokers.Conclusion: Nicotine dependence criteria are associated with a higher probability of pain than having no nicotine dependence criteria in this general population sample.
A study of visual and tactile terrain classification and classifier fusion for planetary exploration rovers
Authors: Halatci Ibrahim , Brooks Christopher A. , Iagnemma Karl 
Published: April 2008

SUMMARYKnowledge of the physical properties of terrain surrounding a planetary exploration rover can be used to allow a rover system to fully exploit its mobility capabilities. Terrain classification methods provide semantic descriptions of the physical nature of a given terrain region. These descriptions can be associated with nominal numerical physical parameters, and/or nominal traversability estimates, to improve mobility prediction accuracy. Here we study the performance of multisensor classification methods in the context of Mars surface exploration. The performance of two classification algorithms for color, texture, and range features are presented based on maximum likelihood estimation and support vector machines. In addition, a classification method based on vibration features derived from rover wheel–terrain interaction is briefly described. Two techniques for merging the results of these “low-level” classifiers are presented that rely on Bayesian fusion and meta-classifier fusion. The performance of these algorithms is studied using images from NASA's Mars Exploration Rover mission and through experiments on a four-wheeled test-bed rover operating in Mars-analog terrain. Also a novel approach to terrain sensing based on fused tactile and visual features is presented. It is shown that accurate terrain classification can be achieved via classifier fusion from visual and tactile features.
A structural approach to the automatic adjudication of word sense disagreements
Authors: NAVIGLI ROBERTO 
Published: April 2008

AbstractThe semantic annotation of texts with senses from a computational lexicon is a complex and often subjective task. As a matter of fact, the fine granularity of the WordNet sense inventory [Fellbaum, Christiane (ed.). 1998.WordNet: An Electronic Lexical DatabaseMIT Press], ade factostandard within the research community, is one of the main causes of a low inter-tagger agreement ranging between 70% and 80% and the disappointing performance of automated fine-grained disambiguation systems (around 65% state of the art in the Senseval-3 English all-words task). In order to improve the performance of both manual and automated sense taggers, either we change the sense inventory (e.g. adopting a new dictionary or clustering WordNet senses) or we aim at resolving the disagreements between annotators by dealing with the fineness of sense distinctions. The former approach is not viable in the short term, as wide-coverage resources are not publicly available and no large-scale reliable clustering of WordNet senses has been released to date. The latter approach requires the ability to distinguish between subtle or misleading sense distinctions. In this paper, we propose the use of structural semantic interconnections – a specific kind of lexical chains – for the adjudication of disagreed sense assignments to words in context. The approach relies on the exploitation of the lexicon structure as a support to smooth possible divergencies between sense annotators and foster coherent choices. We perform a twofold experimental evaluation of the approach applied to manual annotations from the SemCor corpus, and automatic annotations from the Senseval-3 English all-words competition. Both sets of experiments and results are entirely novel: structural adjudication allows to improve the state-of-the-art performance in all-words disambiguation by 3.3 points (achieving a 68.5% F1-score) and attains figures around 80% precision and 60% recall in the adjudication of disagreements from human annotators.
Disparities in pension systems and financial flows among European countries
Authors: CHATEAU JEAN , CHOJNICKI XAVIER , MAGNANI RICCARDO 
Published: April 2008

AbstractWe present a quantitative analysis of the impact of differential ageing and pension reforms on capital and labor market and, in particular, on intra-European capital flows. To this end, we develop a stylized general equilibrium model with overlapping generations of heterogeneous agents for the three largest European countries: France, Germany and the United Kingdom. The model presents a structure halfway between pure general equilibrium models with rigorous microeconomic foundations and accounting models where the macroeconomic environment remains exogenous. We show that the dynamics of capital accumulation and pension system sustainability are totally different depending on the assumption concerning economic openness. Finally, in the long run, resorting to debt financing seems to be a dead end to finance retirement systems.
Mast cells can contribute to axon–glial dissociation and fibrosis in peripheral nerve
Authors: Monk Kelly R. , Wu Jianqiang , Williams Jon P. , Finney Brenda A. , Fitzgerald Maureen E. , Filippi Marie-Dominique , Ratner Nancy 
Published: April 2008

AbstractExpression of the human epidermal growth factor receptor (EGFR) in murine Schwann cells results in loss of axon–Schwann cell interactions and collagen deposition, modeling peripheral nerve response to injury and tumorigenesis. Mast cells infiltrate nerves in all three situations. We show that mast cells are present in normal mouse peripheral nerve beginning at 4 weeks of age, and that the number of mast-cells in EGFR+ nerves increases abruptly at 5–6 weeks of age as axons and Schwann cells dissociate. The increase in mast cell number is preceded and accompanied by elevated levels of mRNAs encoding the mast-cell chemoattractants Rantes, SCF and VEGF. Genetic ablation of mast cells and bone marrow reconstitution in W41 × EGFR+ mice indicate a role for mast cells in loss of axon−Schwann cell interactions and collagen deposition. Pharmacological stabilization of mast cells by disodium cromoglycate administration to EGFR+ mice also diminished loss of axon−Schwann cell interaction. Together these three lines of evidence support the hypothesis that mast cells can contribute to alterations in peripheral nerves.
Events at the transition between cell cycle exit and oligodendrocyte progenitor differentiation: the role of HDAC and YY1
Authors: He Ye , Sandoval Juan , Casaccia-Bonnefil Patrizia 
Published: April 2008

AbstractThe complexity of the adult brain is the result of an integrated series of developmental events that depends on appropriate timing of differentiation. The importance of transcriptional regulatory networks and epigenetic mechanisms of regulation of gene expression is becoming increasingly evident. Among these mechanisms, previous work has revealed the importance of histone deacetylation in oligodendrocyte differentiation. In this manuscript we define the region of interaction between transcription factor Yin-Yang 1 (YY1) and histone deacetylase 1, and characterize the functional consequences of YY1 overexpression on the differentiation of oligodendrocyte progenitors.
Reduced EGFR signaling in progenitor cells of the adult subventricular zone attenuates oligodendrogenesis after demyelination
Authors: Aguirre Adan , Gallo Vittorio 
Published: April 2008

AbstractNeural progenitor cells that express the NG2 proteoglycan are present in different regions of the adult mammalian brain where they display distinct morphologies and proliferative rates. In the developing postnatal and adult mouse, NG2+ cells represent a major cell population of the subventricular zone (SVZ). NG2+ cells divide in the anterior and lateral region of the SVZ, and are stimulated to proliferate and migrate out of the SVZ by focal demyelination of the corpus callosum (CC). Many NG2+ cells are labeled by GFP-retrovirus injection into the adult SVZ, demonstrating that NG2+ cells actively proliferate under physiological conditions and after demyelination. Under normal physiological conditions and after focal demyelination, proliferation of NG2+ cells is significantly attenuated in wa2 mice, which are characterized by reduced signaling of the epidermal growth factor receptor (EGFR). This results in reduced SVZ-to-lesion migration of NG2+ cells and oligodendrogenesis in the lesion. Expression of vascular endothelial growth factor (VEGF) and EGFR ligands, such as heparin binding-EGF and transforming growth factor α, is upregulated in the SVZ after focal demyelination of the CC. EGF-induced oligodendrogenesis and myelin protein expression in wild-type SVZ cells in culture are significantly attenuated in wa2 SVZ cells. Our results demonstrate that the response of NG2+ cells in the SVZ and their subsequent differentiation in CC after focal demyelination depend on EGFR signaling.
Supportive or information-processing functions of the mature protoplasmic astrocyte in the mammalian CNS? A critical appraisal
Authors: Kimelberg Harold K. 
Published: April 2008

AbstractIt has been proposed that astrocytes should no longer be viewed purely as support cells for neurons, such as providing a constant environment and metabolic substrates, but that they should also be viewed as being involved in affecting synaptic activity in an active way and, therefore, an integral part of the information-processing properties of the brain. This essay discusses the possible differences between a support and an instructive role, and concludes that any distinction has to be blurred. In view of this, and a brief overview of the nature of the data, the new evidence seems insufficient to conclude that the physiological roles of mature astrocytes go beyond a general support role. I propose a model of mature protoplasmic astrocyte function that is drawn from the most recent data on their structure, the domain concept and their syncytial characteristics, of an independent rather than integrative functioning of the ends of each process where the activities that affect synaptic activity and blood vessel diameter will be concentrated.