bluuebunny/crossref_metadata_2025 huggingface dataset:
Context‐dependent variation in social stereotyping 3: Extremism as a self‐categorical basis for polarized judgement
Authors: Haslam S. Alexander , Turner John C.
Published: May 2007

A large body of research suggests that extremists make more accentuated (‘black and white’) judgements than moderates. This phenomenon has been explained in terms of individual differences associated with extremism or as the product of general processes of social judgement. Self‐categorization theory suggests that extremists represent the world in relatively polarized terms only because, and to the extent that, similar others are more similar to them and different others are more different from them than is the case for moderates. This analysis is tested and supported in three experiments (Ns = 61, 101, 69) which (a) manipulate subjects' extremity and reproduce standard accentuation effects, and (b) change the configuration of the comparative features comprising the judgmental context and reverse these effects. These findings are inconsistent with individual difference explanations of accentuation and extend previous social judgemental theorizing. Implications for the conceptualization of extremism are also discussed.
Social interactions, stressful events and negative affect at work: A micro‐analytic approach
Authors: Peeters Maria C. W. , Buunk Bram P. , Schaufeli Wilmar B.
Published: May 2007

In the present study a daily event‐recording method, the DIRO (Daily Interaction Record in Organizations), was employed for assessing social interactions, stressful events and negative affect at work. Forty‐one secretaries filled out the records during the course of a week. This made it possible to consider both between‐and within‐subject effects of social interactions. The results showed that the social interactions of secretaries were characterized by three dimensions: intimate support, instrumental support and rewarding companionship. These three dimensions appeared to have different relationships with occupational stress. Instrumental support seemed to play the most important role in the work of secretaries, whereas rewarding companionship played no role at all in alleviating occupational stress. In the discussion some explanations are offered for this unexpected result.
How context‐independent is the outgroup homogeneity effect? A response to Bartsch and Judd
Authors: Haslam S. Alexander , Oakes Penelope J.
Published: May 2007

Bartsch and Judd (1993) argue that outgroup homogeneity effects occur independently of any tendency for members of minority groups to see their ingroup as more homogeneous than the majority outgroup. This argument is based on evidence of an underlying outgroup homogeneity effect in a study which purports to unconfound the roles of judged group size and ingroup–outgroup judgement by presenting subjects first with a small or large ingroup (or outgroup) and then a small comparison outgroup (or ingroup). However, from the perspective of self‐categorization theory (SCT), such a procedure actually introduces a confound as SCT predicts that when an ingroup is judged first it should be perceived as relatively heterogeneous due to the intragroup nature of this judgemental context. Close examination of Bartsch and Judd's data bears this point out: the tendency to see the ingroup as less homogeneous than the outgroup when the ingroup was judged first was extinguished when the ingroup was judged second even when the judged groups were of equal size. Consistent with SCT, this re‐analysis suggests that manifestations of outgroup homogeneity are not independent of contextual factors which determine the relative appropriateness of category‐based perception of ingroup and outgroup.
The third person effect: Social distance and perceived media bias
Authors: Gibbon Peter , Durkin Kevin
Published: May 2007

Two studies were conducted to determine the conditions under which the third person effect (Davison, 1983) operates. It was hypothesized that the effect would be accentuated as target groups of others became more remote from the self. A second objective was to determine whether the effect operates in the absence of overtly persuasive intent in the media. Television programmes concerned with moral themes were employed as stimuli. The results further support Davison's claim that overestimation of media effects is greater when people imagine the responses of others whom they do not know than those of familar individuals. The results also indicate that the third person effect does operate in the absence of perceived persuasive intent, but is accentuated when bias is perceived by viewers.
Racial categorization and preference among older children in The Netherlands
Authors: Verkumen Maykel , Masson Kees , Elffers Henk
Published: May 2007

In this study the pervasiveness of racial categorization is investigated among children (10–12 years of age) in multi‐racial schools. Subjects were asked to sort photographs of unknown contemporaries and to indicate preferences. Skin colour, sex and facial expression were used as three characteristics which varied systematically in the pictures. The results show, first, that children preferred to use different features simultaneously instead of a single feature only. Second, in a dichotomous classification task skin colour and sex were the most obvious visible features used for categorization. Gender was also used for explaining socially undesirable behaviour, and for indicating preferences. while race was not used in these tasks. In indicating preferences facial expression and not skin colour was used as a subordinate category. There were very few differences between ethnic Dutch, coloured and ethnic minority children in the use of skin colour or other features.
How the sperm dominates the ovum — objectification by metaphor in the social representation of conception
Authors: Wagner Wolfgang , Elejabarrieta Fran , Lahnsteiner Ingrid
Published: May 2007

This investigation is about the use of metaphors in the everyday understanding of conception. It is argued that the analysis of the relationship between source and target domain in a metaphor used as an objectification device can help explain how social representations are acquired collectively and individually. We expect that in popular knowledge of conception the central metaphors and images relate to the subjects' everyday experience as social actors and sexual beings because social and sexual experience is pervasive and well‐understood. In an experimental questionnaire study involving 169 subjects, it is shown as hypothesized that subjects prefer to compare the process of fertilization, i.e. the role and behaviour of sperms and ovum, with sexual and sex‐role behaviour where the role of men is projected upon sperms and the role of women upon the ovum. This implies that sperms are seen not only as more active, but also as harder, stronger, and more dominant than the ovum. These effects are stronger, the more subjects personally subscribe to a more conservative sex‐role orientation. In the discussion it is suggested that it is necessary to analyse the two intricately linked levels of objectification, the cognitive process of selecting specific images and the social process of the diffusion of popular knowledge, if we want to understand how common sense works.
Determination of Piroxicam in Pharmaceutical Formulations Combining Amperometry and Multicommutation
Authors: Silva M. Luísa S. , Garcia M. Beatriz Q. , Lima José L. F. C. , Barrado E.
Published: May 2007

This work describes the development of a multicommutated flow system with amperometric detection, applied in the determination of piroxicam in pharmaceutical formulations.
Electrochemical Preparation of Poly(Malachite Green) Film Modified Nafion‐Coated Glassy Carbon Electrode and Its Electrocatalytic Behavior Towards NADH, Dopamine and Ascorbic Acid
Authors: Chen Shen‐Ming , Chen Ji‐Yan , Thangamuthu R.
Published: May 2007

Poly(malachite green) film modified Nafion‐coated glassy carbon electrodes have been prepared by potentiodynamic cycling in malachite green solution. The pH of polymerisation solution has only minor effect on film formation. Electrochemical quartz crystal microbalance (EQCM) was used to monitor the growth of the poly(malachite green) film. Cyclic voltammogram of the poly(malachite green) film shows a redox couple with well‐defined peaks. The redox response of the modified electrode was found to be depending on the pH of the contacting solution. The peak potentials were shifted to a less positive region with increasing pH and the dependence of the peak potential was found to be 56 mV per pH unit. The electrocatalytic behavior of poly(malachite green) film modified Nafion‐coated glassy carbon electrodes was tested towards oxidation of NADH, dopamine, and ascorbic acid. The oxidation of dopamine and ascorbic acid occurred at less positive potential on poly(malachite green) film compared to bare glassy carbon electrode. In the case of NADH, the overpotential was reduced substantially on modified electrode. Finally, the feasibility of utilizing poly(malachite green) film electrode in analytical estimation of ascorbic acid was demonstrated in flow injection analysis.
Fragility assessment of building structural systems in Mid‐America
Authors: Ellingwood Bruce R. , Celik Ozan Cem , Kinali Kursat
Published: May 2007

Uncertainty in response of buildings and other civil infrastructure to earthquake ground motion is due to the inherent randomness in the ground motion itself—peak intensity, time‐varying amplitude and strong‐motion duration, and frequency content—and local design and construction practices. In the recently completed SAC project and ongoing research in the Pacific Earthquake Engineering Research (PEER) Center, the focus is on performance of buildings designed for regions of high seismicity. In contrast, current research in the Mid‐America Earthquake (MAE) Center is examining the potential impact of earthquakes on building construction in regions of low‐to‐moderate seismicity in the Central and Eastern United States (CEUS) where design and construction practices seldom have made provision for earthquake resistance. This paper assesses the seismic fragilities of several typical low‐to‐mid‐rise steel and reinforced concrete buildings representative of design and construction practices in the CEUS. A comparison of these fragilities with those incorporated in HAZUS carries implications for damage and loss estimation in this region. Copyright © 2007 John Wiley & Sons, Ltd.
Noncanonical spike‐related BOLD responses in focal epilepsy
Authors: Lemieux Louis , Laufs Helmut , Carmichael David , Paul Joseph Suresh , Walker Matthew C. , Duncan John S.
Published: May 2007

Till now, most studies of the Blood Oxygen Level‐Dependent (BOLD) response to interictal epileptic discharges (IED) have assumed that its time course matches closely to that of brief physiological stimuli, commonly called the canonical event‐related haemodynamic response function (canonical HRF). Analyses based on that assumption have produced significant response patterns that are generally concordant with prior electroclinical data. In this work, we used a more flexible model of the event‐related response, a Fourier basis set, to investigate the presence of other responses in relation to individual IED in 30 experiments in patients with focal epilepsy. We found significant responses that had a noncanonical time course in 37% of cases, compared with 40% for the conventional, canonical HRF‐based approach. In two cases, the Fourier analysis suggested activations where the conventional model did not. The noncanonical activations were almost always remote from the presumed generator of epileptiform activity. In the majority of cases with noncanonical responses, the noncanonical responses in single‐voxel clusters were suggestive of artifacts. We did not find evidence for IED‐related noncanonical HRFs arising from areas of pathology, suggesting that the BOLD response to IED is primarily canonical. Noncanonical responses may represent a number of phenomena, including artefacts and propagated epileptiform activity. Hum Brain Mapp 2008. © 2007 Wiley‐Liss, Inc.
Specific Processes and Scrambling in the Dehydrogenation of Ethane and the Degenerate Hydrogen Exchange in the Gas‐Phase Ion Chemistry of the Ni(C,H3,O)+/C2H6 Couple
Authors: Schlangen Maria , Schwarz Helmut , Schröder Detlef
Published: May 2007

A mechanistically unprecedented situation characterizes the gas‐phase ion chemistry of Ni(C,H3,O)+ when reacted under thermal, single‐collision conditions with ethane. A dehydrogenation channel leading to Ni(C3,H7,O)+ is to 90% preceded by a complete loss of positional identity of all nine H‐atoms of the encounter complex (‘scrambling’), whereas ca. 10% of the reaction exhibit a selective CH bond activation of the alkane. In addition, a degenerate H exchange between ethane and the (C,H3,O) unit occurs as a side reaction, the mechanistic details of which remain unknown for the time being.
Synthesis and Qualitative Olfactory Evaluation of Benzodioxepine Analogues
Authors: Drevermann Britta , Lingham Anthony R. , Hügel Helmut M. , Marriott Philip J.
Published: May 2007

Marine fragrances, particularly Calone 1951® (=7‐methyl‐2H‐1,5‐benzodioxepin‐3(4H)‐one; 1) has carved a minor but distinct niche in the broad field of fragrance chemistry. By focusing on the polar structure fragment of the benzodioxepinone parent compound, we set out to determine the molecular influence on the dominant marine note attributed to the Calone 1951® structure. A selection of one‐step modifications of the ketone 1 resulted in a range of odor‐active conformers with diverse olfactory attributes. The synthesis of a range of benzodioxepine analogues, i.e., of 3–11, is presented alongside olfactory evaluation (Tables 2 and 3). Removal of the carbonyl group of 1 and increasing the size of the aliphatic ring portion (see 6 and 7) introduced sweetness and a predominant loss of the marine character.
Oligonucleotide Analogues with Integrated Bases and Backbone. Part 15
Authors: Zhang Xiaomin , Bernet Bruno , Vasella Andrea
Published: May 2007

The self‐complementary (Z)‐configured U*[ce]A(*) dinucleotide analogues 6, 8, 10, 12, 14, and 16, and the A*[ce]U(*) dimers 19, 21, 23, 25, 27, and 29 were prepared by partial hydrogenation of the corresponding ethynylene linked dimers. Photolysis of 14 led to the (E)‐alkene 17. These dinucleotide analogues associate in CDCl3 solution, as evidenced by NMR and CD spectroscopy. The thermodynamic parameters of the duplexation were determined by van't Hoff analysis. The (Z)‐configured U*[ce]A(*) dimers 14 and 16 form cyclic duplexes connected by Watson–Crick H‐bonds, the (E)‐configured U*[ce]A dimer 17 forms linear duplexes, and the U*[ce]A(*) allyl alcohols 6, 8, 10, and 12 form mixtures of linear and cyclic duplexes. The C(6/I)‐unsubstituted A*[ce]U allyl alcohols 19 and 23 form linear duplexes, whereas the C(6/I)‐substituted A*[ce]U* allyl alcohols 21 and 25, and the C(5′/I)‐deoxy A*[ce]U(*) dimers 27 and 29 also form minor amounts of cyclic duplexes. The influence of intra‐ and intermolecular H‐bonding of the allyl alcohols and the influence of the base sequence upon the formation of cyclic duplexes are discussed.
Donor/Acceptor Effects on the Linear and Nonlinear Optical Properties of Geminal Diethynylethenes (g‐DEEs)
Authors: Zhao Yuming , Zhou Ningzhang , Slepkov Aaron D. , Ciulei Sorin C. , McDonald Robert , Hegmann Frank A. , Tykwinski Rik R.
Published: May 2007

A series of geminal diethynylethenes (g‐DEEs) with electron‐donating and/or electron‐accepting (D/A) groups were synthesized via a Pd‐catalyzed cross‐coupling sequence. The UV/VIS spectra for donor–acceptor (D–A) functionalized g‐DEEs 5, 8, and 11 show distinctive absorption trends attributable to intramolecular charge‐transfer (ICT). The bond‐length‐alternation (BLA) index for the cross‐conjugated enediyne framework varies slightly with different terminal substituents as determined by density‐functional theory (DFT) calculations and single‐crystal X‐ray analysis. Ultrafast third‐order optical nonlinearities for the g‐DEEs were measured by the differential optical Kerr effect (DOKE) technique and show that terminal donor–acceptor substitution of g‐DEEs enhances molecular second hyperpolarizabilities (γ) in comparison to donor or acceptor g‐DEEs. A small increase in the two‐photon‐absorption cross‐section (σ(2)) is observed in the series 9–11 as a result of increased functionalization. The effects of donor/acceptor substitution on electron delocalization along the cross‐conjugated enediyne structure are evaluated on the basis of natural‐bond‐orbital (NBO) analysis. Solid‐state structures of the four derivatives 3b, 4b, 7 and 8 were characterized by single‐crystal X‐ray structural analysis and show an asymmetric unit cell for one derivative, D–A g‐DEE 8.
A Novel Method for the Asymmetric Synthesis of α,β‐Diamino Acids by a Glucose‐Mediated Stereoselective Strecker Reaction
Authors: Wang Dong , Zhang Peng‐Fei , Yu Biao
Published: May 2007

A novel method for the asymmetric synthesis of α,β‐diamino acids by using the 2,3,4,6‐tetra‐O‐pivaloyl‐β‐D‐glucopyranosyl group (Piv4Glc) as chiral auxiliary was developed (Table and Scheme). The reaction was promoted by CuBr⋅Me2S as Lewis acid, and high yields and good diastereoselectivities were achieved.
Synthesis and Structure of 2‐Substituted Thieno[3′,2′:5,6]pyrido[4,3‐d]pyrimidin‐4(3H)‐one Derivatives
Authors: Liu Jian‐Chao , He Hong‐Wu , Ding Ming‐Wu
Published: May 2007

A series of new 2‐substituted 3‐(4‐chlorophenyl)‐5,8,9‐trimethylthieno[3′,2′: 5,6]pyrido[4,3‐d]pyrimidin‐4(3H)‐ones 8 were synthesized via an aza‐Wittig reaction. Phosphoranylideneamino derivatives 6a or 6b reacted with 4‐chlorophenyl isocyanate to give carbodiimide derivatives 7a or 7b, respectively, which were further treated with amines or phenols to give compounds 8 in the presence of a catalytic amount of EtONa or K2CO3. The structure of 2‐(4‐chlorophenoxy)‐3‐(4‐chlorophenyl)‐5,8,9‐trimethylthieno[3′,2′: 5,6]pyrido[4,3‐d]pyrimidin‐4(3H)‐one (8j) was comfirmed by X‐ray analysis.
Evaluating the potential of a blended passive microwave‐interactive multi‐sensor product for improved mapping of snow cover and estimations of snow water equivalent
Authors: Kongoli Cezar , Dean Charles A. , Helfrich Sean R. , Ferraro Ralph R.
Published: May 2007

The retrieval of Snow Water Equivalent (SWE) from remote sensing satellites continues to be a very challenging problem. In this paper, we evaluate the accuracy of a new SWE product derived from the blending of a passive microwave SWE product based on the Advanced Microwave Sounding Unit (AMSU) with a multi‐sensor snow cover extent product based on the Interactive Multi‐sensor Snow and Ice Mapping System (IMS). The microwave measurements have the ability to penetrate the snow pack, and thus, the retrieval of SWE is best accomplished using the AMSU. On the other hand, the IMS maps snow cover more reliably due to the use of multiple satellite and ground observations. The evolution of global snow cover from the blended, the AMSU and the IMS products was examined during the 2006 snow season. Despite the overall good inter‐product agreement, it was shown that the retrievals of snow cover extent in the blended product are improved when using IMS, with implications for improved microwave retrievals of SWE. In a separate investigation, the skill of the microwave SWE product was also examined for its ability to correctly estimate SWE globally and regionally. Qualitative evaluation of global SWE retrievals suggested dependence on land surface temperature: the lower the temperature, the higher the SWE retrieved. This temperature bias was attributed in part to temperature effects on those snow properties that impact microwave response. Therefore, algorithm modifications are needed with more dynamical adjustments to account for changing snow cover. Quantitative evaluation over Slovakia in central Europe, for a limited period in 2006, showed reasonably good performance for SWE less than 100 mm. Sensitivity to deeper snow decreased significantly. Copyright © 2007 John Wiley & Sons, Ltd.
Oxidative damage in mild cognitive impairment and early Alzheimer's disease
Authors: Lovell Mark A. , Markesbery William R.
Published: May 2007

Increasing evidence supports a role for oxidative damage in the pathogenesis of Alzheimer's disease (AD). Multiple studies show significantly increased levels of lipid peroxidation and protein, DNA, and RNA oxidation in vulnerable regions of the brain of patients with late‐stage AD (LAD). More recent studies of patients with amnestic mild cognitive impairment (MCI), the earliest clinical manifestation of AD, show similar patterns of oxidative damage. These observations suggest that oxidative damage to critical biomolecules occurs early in the pathogenesis of AD and precedes pronounced neuropathologic alterations. Because oxidative damage begins early in the progress of the disease, it represents a potential therapeutic target for slowing the onset and progression of AD. © 2007 Wiley‐Liss, Inc.
β‐amyloid (25–35) enhances lipid metabolism and protein ubiquitination in cultured neurons
Authors: Cazzaniga Emanuela , Bulbarelli Alessandra , Cassetti Arianna , Lonati Elena , Re Francesca , Palestini Paola , Mutoh Tatsuro , Masserini Massimo
Published: May 2007

We investigated the effect of β‐amyloid (Aβ) (25–35), a cytotoxic fragment of Aβ peptide, on lipid metabolism and protein ubiquitination in cultured rat hippocampal neurons. After treatment with Aβ under conditions leading to apoptotis, as assessed by caspase activity assay, the total cell mass of lipids changed following a biphasic behavior, with an increase that reached a maximum after 16 hr of treatment, followed by a decrease. The increase at 16 hr was 15.3% in the case of phospholipids and 103.0% in the case of gangliosides and was due to enhanced biosynthesis as confirmed by increase of radioactivity incorporation (phospholipids +52.0%, gangliosides +193.1%) in cells fed with tritiated palmitic acid. No change with respect to cholesterol was observed. Strikingly, under these conditions, the ubiquitination state of cell proteins strongly increased. These effects were not observed with the (35–25) reverse sequence peptide. Similarly to Aβ, lactacystin treatment increased lipid synthesis and protein ubiquitination; only lactacystin, and not Aβ, induced a strong decrease of proteasome chimotrypsin activity. These results suggest that Aβ enhances protein ubiquitination, without inhibiting proteasomal activity, and lipid synthesis. These results may shed new light on the mechanisms of Aβ toxicity. © 2007 Wiley‐Liss, Inc.
Regulatory factor X4 variant 3: A transcription factor involved in brain development and disease
Authors: Zhang Donghui , Zeldin Darryl C. , Blackshear Perry J.
Published: May 2007

Regulatory factor X4 variant 3 (RFX4_v3) is a recently identified transcription factor specifically expressed in the brain. Gene disruption in mice demonstrated that interruption of a single allele (heterozygous, +/–) prevented formation of the subcommissural organ (SCO), resulting in congenital hydrocephalus, whereas interruption of two alleles (homozygous, –/–) caused fatal failure of dorsal midline brain structure formation. These mutagenesis studies implicated RFX4_v3 in early brain development as well as the genesis of the SCO. Rfx4_v3 deficiency presumably causes abnormalities in brain by altering the expression levels of many genes that are crucial for brain morphogenesis, such as the signaling components in the Wnt, bone morphogenetic protein, and retinoic acid pathways. RFX4_v3 might affect these critical signaling pathways in brain development. Cx3cl1, a chemokine gene highly expressed in brain, was identified as a direct target for RFX4_v3, indicating that RFX4_v3 possesses trans‐acting activity to stimulate gene expression. Rfx4_v3 is highly expressed in the suprachiasmatic nucleus and might be involved in regulating the circadian clock. One haplotype in RFX4_v3 gene is linked to a higher risk of bipolar disorder, suggesting that this protein might contribute to the pathogenesis of the disease. This Mini‐Review describes our current knowledge about RFX4_v3, an important protein that appears to be involved in many aspects of brain development and disease. © 2007 Wiley‐Liss, Inc.
Peroxynitrite‐mediated oxidative damage to brain mitochondria: Protective effects of peroxynitrite scavengers
Authors: Singh Indrapal N. , Sullivan Patrick G. , Hall Edward D.
Published: May 2007

Peroxynitrite‐mediated oxidative damage has been implicated in brain mitochondrial respiratory dysfunction after traumatic brain injury (TBI), which precedes the onset of neuronal loss. The aim of this study was to investigate the detrimental effects of the peroxynitrite donor SIN‐1 (3‐morpholinosydnonimine) on isolated brain mitochondria and to screen penicillamine, a stoichiometric (1:1) peroxynitrite‐scavenging agent, and tempol, a catalytic scavenger of peroxynitrite‐derived radicals, as antioxidant mitochondrial protectants. Exposure of the isolated mitochondria to SIN‐1 caused a significant dose‐dependent decrease in the respiratory control ratio and was accompanied by a significant increase in state II respiration, followed by significant decreases (P < 0.05) in states III and V. These functional alterations occurred together with significant increases in mitochondrial protein carbonyl (PC), lipid peroxidation–related 4‐hydroxynonenal (4‐HNE), and 3‐nitrotyrosine (3‐NT) content. Penicillamine hydrochloride (10 μM) partially but significantly (P < 0.05) protected against SIN‐1‐induced decreases in states III and V. However, a 2.5 μM concentration of tempol was able to significantly antagonize a 4‐fold molar excess (10 μM) concentration of SIN‐1 as effectively as were higher tempol concentrations, consistent with the likelihood that tempol works by a catalytic mechanism. The protection of mitochondrial respiration by penicillamine and tempol occurred in parallel with attenuation of PC, 4‐HNE, and 3‐NT. These results indicate that SIN‐1 causes mitochondrial oxidative damage and complex I dysfunction and that antioxidant compounds that target either peroxynitrite or its radicals may be effective mitochondrial protectants in the treatment of neural injury. © 2007 Wiley‐Liss, Inc.
Evidence that nucleocytoplasmic Olig2 translocation mediates brain‐injury‐induced differentiation of glial precursors to astrocytes
Authors: Magnus Tim , Coksaygan Turhan , Korn Thomas , Xue Haipeng , Arumugam Thiruma V. , Mughal Mohamed R. , Eckley D. Mark , Tang Sung‐Chun , DeTolla Louis , Rao Mahendra S. , Cassiani‐Ingoni Riccardo , Mattson Mark P.
Published: May 2007

The mechanisms by which neural and glial progenitor cells in the adult brain respond to tissue injury are unknown. We studied the responses of these cells to stab wound injury in rats and in two transgenic mouse models in which Y/GFP is driven either by Sox2 (a neural stem cell marker) or by Tα‐1 (which marks newly born neurons). The response of neural progenitors was low in all nonneurogenic regions, and no neurogenesis occurred at the injury site. Glial progenitors expressing Olig2 and NG2 showed the greatest response. The appearance of these progenitors preceded the appearance of reactive astrocytes. Surprisingly, we found evidence of the translocation of the transcription factor Olig2 into cytoplasm in the first week after injury, a mechanism that is known to mediate the differentiation of astrocytes during brain development. Translocation of Olig2, down‐regulation of NG2, and increased glial fibrillary acidic protein expression were recapitulated in vitro after exposure of glial progenitors to serum components or bone morphogentic protein by up‐regulation of Notch‐1. The glial differentiation and Olig2 translocation could be blocked by inhibition of Notch‐1 with the γ‐secretase inhibitor DAPT. Together, these data indicate that the prompt maturation of numerous Olig2+ glial progenitors to astrocytes underlies the repair process after a traumatic injury. In contrast, neural stem cells and neuronal progenitor cells appear to play only a minor role in the injured adult CNS. © 2007 Wiley‐Liss, Inc.
Locally delivered lovastatin nanoparticles enhance fracture healing in rats
Authors: Garrett I.R. , Gutierrez G.E. , Rossini G. , Nyman J. , McCluskey B. , Flores A. , Mundy G.R.
Published: May 2007

Statins stimulate bone formation in vitro and in vivo and, when given in large doses or by prolonged infusions, stimulate biomechanical strength of murine long bones with healing fractures. However, administration of statins by large oral doses or prolonged infusions to a fracture site is not a feasible therapeutic approach to hasten healing of human fractures. We administered lovastatin in biodegradable polymer nanobeads of poly(lactic‐co‐glycolide acid) to determine if lovastatin delivered in low doses in nanoparticles of a therapeutically acceptable scaffold could increase rates of healing in a standard preclinical model of femoral fracture. We found that these nanobeads: (1) stimulated bone formation in vitro at 5 ng/mL, (2) increased rates of healing in femoral fractures when administered as a single injection into the fracture site, and (3) decreased cortical fracture gap at 4 weeks as assessed by microcomputed tomography. These preclinical results suggest that lovastatin administered in a nanobead preparation may be therapeutically useful in hastening repair of human fractures. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:1351–1357, 2007
Decreased muscle loading delays maturation of the tendon enthesis during postnatal development
Authors: Thomopoulos Stavros , Kim Hyun‐Min , Rothermich Stefan Y. , Biederstadt Carrie , Das Rosalina , Galatz Leesa M.
Published: May 2007

Physical environment influences the development and maintenance of musculoskeletal tissues. The current study uses an animal model to explore the role of the physical environment on the postnatal development of the supraspinatus tendon enthesis. A supraspinatus intramuscular injection of botulinum toxin A was used to paralyze the left shoulders of mice at birth. The supraspinatus muscles of right shoulders were injected with saline to serve as contralateral controls. The supraspinatus enthesis was examined after 14, 21, 28, and 56 days of postnatal development. Histologic assays were used to examine fibrocartilage morphology and percentage osteoclast surface. Micro‐computed tomography was used to examine muscle geometry and bone architecture. At 14 days there were no differences between groups in fibrocartilage formation, muscle geometry, bone architecture, or osteoclast surface. When comparing groups at 21, 28, and 56 days, muscle volume was decreased, fibrocartilage development was delayed, mineralized bone was decreased, and osteoclast surface was higher at each timepoint in the botulinum group compared to the contralateral saline control group. Our results indicate that the development of the tendon enthesis is sensitive to its mechanical environment. A reduction in muscle loading delayed the development of the tendon‐to‐bone insertion site by impeding the accumulation of mineralized bone. Physical factors did not play a significant role in enthesis maturation in the first 14 days postnatally, implying that biologic factors may drive early postnatal development. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:1154–1163, 2007
Quantifier elimination for the theory of algebraically closed valued fields with analytic structure
Authors: Çelikler Yalın F.
Published: May 2007

The theory of algebraically closed non‐Archimedean valued fields is proved to eliminate quantifiers in an analytic language similar to the one used by Cluckers, Lipshitz, and Robinson. The proof makes use of a uniform parameterized normalization theorem which is also proved in this paper. This theorem also has other consequences in the geometry of definable sets. The method of proving quantifier elimination in this paper for an analytic language does not require the algebraic quantifier elimination theorem of Weispfenning, unlike the customary method of proof used in similar earlier analytic quantifier elimination theorems. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On n ‐contractive fuzzy logics
Authors: Horčík Rostislav , Noguera Carles , Petrík Milan
Published: May 2007

It is well known that MTL satisfies the finite embeddability property. Thus MTL is complete w. r. t. the class of all finite MTL‐chains. In order to reach a deeper understanding of the structure of this class, we consider the extensions of MTL by adding the generalized contraction since each finite MTL‐chain satisfies a form of this generalized contraction. Simultaneously, we also consider extensions of MTL by the generalized excluded middle laws introduced in [9] and the axiom of weak cancellation defined in [31]. The algebraic counterpart of these logics is studied characterizing the subdirectly irreducible, the semisimple, and the simple algebras. Finally, some important algebraic and logical properties of the considered logics are discussed: local finiteness, finite embeddability property, finite model property, decidability, and standard completeness. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A generalization of the Keisler‐Morley theorem to recursively saturated ordered structures
Authors: Mohsenipour Shahram
Published: May 2007

We prove a model theoretic generalization of an extension of the Keisler‐Morley theorem for countable recursively saturated models of theories having a κ ‐like model, where κ is an inaccessible cardinal. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Kripke submodels and universal sentences
Authors: Ellison Ben , Fleischmann Jonathan , McGinn Dan , Ruitenburg Wim
Published: May 2007

We define two notions for intuitionistic predicate logic: that of a submodel of a Kripke model, and that of a universal sentence. We then prove a corresponding preservation theorem. If a Kripke model is viewed as a functor from a small category to the category of all classical models with (homo)morphisms between them, then we define a submodel of a Kripke model to be a restriction of the original Kripke model to a subcategory of its domain, where every node in the subcategory is mapped to a classical submodel of the corresponding classical model in the range of the original Kripke model. We call a sentence universal if it is built inductively from atoms (including ⊤ and ⊥) using ∧, ∨, ∀, and →, with the restriction that antecedents of → must be atomic. We prove that an intuitionistic theory is axiomatized by universal sentences if and only if it is preserved under Kripke submodels. We also prove the following analogue of a classical model‐consistency theorem: The universal fragment of a theory Γ is contained in the universal fragment of a theory Δ if and only if every rooted Kripke model of Δ is strongly equivalent to a submodel of a rooted Kripke model of Γ. Our notions of Kripke submodel and universal sentence are natural in the sense that in the presence of the rule of excluded middle, they collapse to the classical notions of submodel and universal sentence. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Coloring linear orders with Rado's partial order
Authors: Camerlo Riccardo , Marcone Alberto
Published: May 2007

Let ⪯R be the preorder of embeddability between countable linear orders colored with elements of Rado's partial order (a standard example of a wqo which is not a bqo). We show that ⪯R has fairly high complexity with respect to Borel reducibility (e.g. if P is a Borel preorder, then P ≤B ⪯R), although its exact classification remains open. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Friction and Wear Mechanisms of Sintered and Thermoplastic Polyimides under Adhesive Sliding
Authors: Samyn Pieter , Schoukens Gustaaf , Verpoort Francis , Van Craenenbroeck Jeroen , De Baets Patrick
Published: May 2007

Polyimides function under high‐temperature sliding. The available literature explains transitions in friction and wear mainly by mechanical effects, such as influences of normal load, sliding velocity and humidity on polymer transfer to steel counterfaces. Theoretical models are evaluated for sintered and thermoplastic polyimides. Tribologists have been interested in tribochemical and tribophysical reactions in the sliding interface for about 25 years. Reactions such as hydrolysis, imidisation and/or degradation occur as a function of sliding temperature and are reviewed in this paper. An overview of polyimide synthesis and degradation is presented, while new insights in sliding mechanisms are obtained from a detailed study of Raman spectroscopy on worn polymer surfaces.

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Electret Properties of Polyetherimides: Influence of Water Content and Comparison with Other High‐Temperature Polymer Films
Authors: Frese Thomas , Lovera Deliani , Sandler Jan K. W. , Lim Goy Teck , Altstädt Volker , Giesa Reiner , Schmidt Hans‐Werner
Published: May 2007

In this comparative study, the charge storage performance of commercial high‐temperature polymer films was evaluated and correlated with their chemical structure. Isothermal surface potential decay measurements after annealing periods at 90 °C revealed that amorphous polyetherimide (PEI) films showed the best charge storage behavior. Polyimide films showed reduced charge storage performance, whereas sulfur‐containing polymer films are not suitable as electrets due to their fast charge decay. Additionally, the effect of water content in PEI films in the range of 0.02–0.79 wt.‐% was studied. Increasing amounts of water decreased the charge storage properties proportionally, but only by a relatively smaller amount: the highest investigated water content of 0.79 wt.‐% reduced the charge by only 30%.

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Synthesis and Thermal Characterization of Some Novel ABA Block Copolymers
Authors: Cicala Gianluca , Mamo Antonino , Recca Giuseppe , Restuccia Carmelo Luca
Published: May 2007

The synthesis of some novel ABA block copolymers is reported. The block A is a PPO while the block B is a random copoly(aryl ether sulfone), synthesized with three different molecular weights. The block copolymers were obtained by a two step procedure consisting on the functionalization of the random copoly(aryl ether sulfone) followed by a condensation with PPO. Spectroscopic techniques (1H NMR and 13C NMR) were used to characterize the polymers obtained from each step. The NMR data proved the complete conversion of amino groups after the first reaction step and gave some useful insights on the completion of the second step. Copolymer formation is supported by a comparison of the thermal behavior of the block copolymers with respect to the physical blends of the two homopolymers. DSC and DMA analyses showed double glass transitions for the physical blends which could be related to the immiscibility of the two homopolymers, while, in contrast, the block copolymer showed single glass transition. Blends of ABA triblock copolymer/PPO and of ABA triblock/copoly(arylen ether sulfone)s were also prepared. These blends, tested by DSC, showed a good level of compatibility of the ABA copolymer with its singular constituents.

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Structured maintenance policies on interior sample paths
Authors: Maillart Lisa M. , Zheltova Ludmila
Published: May 2007

We examine the problem of adaptively scheduling perfect observations and preventive replacements for a multi‐state, Markovian deterioration system with silent failures such that total expected discounted cost is minimized. We model this problem as a partially observed Markov decision process and show that the structural properties of the optimal policy hold for certain non‐extreme sample paths. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007
The first prenatal diagnosis for veno‐occlusive disease and immunodeficiency syndrome, an autosomal recessive condition associated with mutations in SP110
Authors: Cliffe Simon T. , Wong Melanie , Taylor Peter J. , Ruga Ezia , Wilcken Bridget , Lindeman Robert , Buckley Michael F. , Roscioli Tony
Published: May 2007

Objectives

We present the first prenatal diagnosis of familial hepatic veno‐occlusive disease with immunodeficiency (VODI). Homozygous mutations in the gene SP110 are the genetic basis of VODI. The proband in this report presented at three months of age with hepatomegaly hepatic failure and was found to have hypogammaglobulinemia. He died one month after hepatic transplant at eight months of age due to hemophagocytic syndrome. DNA testing detected a homozygous truncating mutation in exon 5; SP110 c.642delC. Prenatal testing was offered to this family in a subsequent pregnancy.

Methods

Chorion villus was sampled at 12 weeks' gestation. DNA was extracted using standard techniques, and sequencing of SP110 exon 5 was performed using flanking primers. Maternal contamination was excluded by examining STR markers in CVS and maternal DNA.

Results

A heterozygous SP110 c.642delC mutation was detected in exon 5. This mutation was present in heterozygous form in both parents.

Conclusions

The prenatal test result is predictive of a child with a normal immune and hepatic phenotype. This report presents the first prenatal molecular diagnosis for VODI and shows the importance of molecular genetic research in not only defining the aetiology of syndromes but also in assisting reproductive choices through the collaboration of genetic and feto‐maternal services. Copyright © 2007 John Wiley & Sons, Ltd.
Effect of soft segment length on properties of hydrophilic/hydrophobic polyurethanes
Authors: Lin Yung‐Hsin , Chou Nai‐Kuan , Chen Kuan‐Fu , Ho Guan‐Huei , Chang Chih‐Hao , Wang Shoei‐Shen , Chu Shu‐Hsun , Hsieh Kuo‐Huang
Published: May 2007

Polyurethanes (PUs) were prepared from 4,4′‐diphenylmethane diisocyanate and various molecular weights of poly(tetramethylene glycol) and polydimethylsiloxane. The physical properties of these polymers were determined using Fourier transform infrared spectroscopy and through calculation of their swelling ratios. The thermal properties were investigated through thermogravimetric analysis and dynamic mechanical analysis. The blood compatibility of each polymer was determined by calculating its relative index of platelet adhesion (RIPA). Domain separation of the resulting PUs occurred during polymerization because of the immiscibility of the hydrophilic and hydrophobic polyols. The hydrophilic/hydrophobic domain‐separated structure affected the surface tension through the formation of hydrophilic and hydrophobic domains of the PU, which reduced the adhesion of blood platelets onto the materials. The PU(PDMS/PTMO1000) = 75/25 sample, with its RIPA of 0.34, appears to be suitable for biomedical applications as a blood‐compatible material. Copyright © 2007 Society of Chemical Industry
Nonlinear optical properties of regioregular main‐chain polyesters
Authors: Centore R. , Riccio P. , Fusco S. , Carella A. , Quatela A. , Schutzmann S. , Stella F. , De Matteis F.
Published: May 2007

We have prepared new polyesters containing quadratic, nonlinear optical (NLO) active chromophores covalently incorporated into the main chain. In these polymers, the sequence of the chromophore units along the main chain is rigorously head to tail. All the polyesters are processable, both in the melt and in solution. For one polyester, a full second‐order NLO characterization has been performed. An out‐of‐resonance d33 coefficient of 21 pm/V at 1368 nm has been measured. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2719–2725, 2007
Synthesis and characterization of model polybutadiene‐1,4‐b‐polydimethylsiloxane‐b‐polybutadiene‐1,4 copolymers
Authors: Ciolino Andrés E. , Villar Marcelo A. , Vallés Enrique M. , Hadjichristidis Nikos
Published: May 2007

Model copolymers of poly(butadiene) (PB) and poly(dimethylsiloxane) (PDMS), PB‐b‐PDMS‐b‐PB, were synthesized by sequential anionic polymerization (high vacuum techniques) of 1,3‐butadiene and hexamethylciclotrisiloxane (D3) on sec‐BuLi followed by chlorosilane‐coupling chemistry. The synthesized copolymers were characterized by nuclear magnetic resonance (1H NMR), size‐exclusion chromatography (SEC), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). SEC and 1H NMR results showed low polydispersity indexes (Mw/Mn) and variable siloxane compositions, whereas DSC and TGA experiments indicated that the thermal stability of the triblock copolymers depends on the PDMS composition. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2726–2733, 2007
Dyspepsia: key considerations for cost‐effective management
Authors: Cawston Jane , Evans Norman
Published: May 2007

PPI prescribing continues to increase for dyspepsia man agement in the UK and the rising cost suggests that alternative options need to be considered. This article looks at the savings achieved with a policy of stepping down or off PPI therapy, with an alginate for acid rebound or break through symptoms. Copyright © 2007 Wiley Interface Ltd
Exubera: first inhaled insulin for the management of diabetes
Authors: Barnett Anthony
Published: May 2007

Exubera is a dry‐powder inhaled formulation of insulin that has now gained licence approval in the UK for use in patients with both type 1 and type 2 diabetes. Here, Professor Barnett discusses the properties of this novel therapeutic option and its potential role in the current and future management of diabetes. Copyright © 2007 Wiley Interface Ltd
Blue–green–red LEDs based on InGaN quantum dots grown by plasma‐assisted molecular beam epitaxy
Authors: Xu Tao , Nikiforov A. Yu , France Ryan , Thomidis Christos , Williams Adrian , Moustakas T. D.
Published: May 2007

Self‐assembled InGaN quantum dots were grown in the Stranski–Krastanov mode by plasma‐assisted molecular beam epitaxy. The average dot height, diameter and density are 3 nm, 30 nm and 7 × 1010 cm–2, respectively. The dot density was found to decrease as the growth temperature increases. The cathodoluminescence emission peak of the InGaN/GaN multiple layer quantum dots (MQDs) was found to red shift 330 meV with respect to the emission peak of the uncapped single layer of InGaN QDs due to Quantum Confined Stark effect. Blue LEDs based on InGaN/GaN multiple quantum wells (MQWs) as well as green and red LEDs based on InGaN MQDs emitting at 440, 560 and 640 nm, respectively, were grown and fabricated. The electroluminescence peak positions of both the green and red InGaN MQD LEDs are shown to be more blue‐shifted with increasing injection current than that of the blue InGaN/GaN MQW LEDs. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Spontaneous growth of uniformly distributed In nanodots and InI3 nanowires on InP induced by a focused ion beam
Authors: Callegari Victor , Nellen Philipp M.
Published: May 2007

We show the growth of hemispherical In nanodots due to differential sputtering by 30 keV gallium (Ga+) ions and of InI3 nanodots and nanowires due to chemical reactions with iodine on the surface of focused ion beam‐irradiated areas on a (100)InP substrate. Growth occurs exclusively on previously FIB‐fabricated nucleation‐sites in the form of craters and trenches. Surface topography and the native oxide on InP are identified as the factors determining the area of growth. Arbitrary 2D patterns can be generated with good control of localization and dimension of the nanostructures. Limitations of size and surface density of the nanodots and nanowires are discussed. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)