bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis and characterization of fluorescence end‐labeled polystyrene via reversible addition‐fragmentation chain transfer (RAFT) polymerization
Authors: Zhou Di , Zhu Xiulin , Zhu Jian , Cheng Zhenping
Published: August 2008

Fluorescence end‐labeled polystyrene (PS) with heteroaromatic carbazole or indole group were prepared conveniently via reversible addition‐fragmentation chain transfer (RAFT) polymerization using dithiocarbamates, ethyl 2‐(9H‐carbazole‐9‐carbonothioylthio)propanoate (ECCP) and benzyl 2‐phenyl‐1H‐indole‐1‐carbodithioate (BPIC) as RAFT agents. The end functionality of obtained PS with different molecular weights was high. The steady‐state and the time‐resolved fluorescence techniques had been used to study the fluorescence behaviors of obtained end‐labeled PS. The fluorescence of dithiocarbamates resulting PS in solid powder cannot be monitored; however, they exhibited structured absorptions and emissions in solvent DMF and the fluorescence lifetimes of PS had no obvious change with molecular weights increasing. These observations suggested that the polymer chains were possibly stretched adequately in DMF, that is, the fluorescence end group was exposed into solvent molecules and little quenching of excited state occurred upon incorporation into polymer chain. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 6198–6205, 2008
Thermal recordable novel cholesteric liquid crystalline polyacrylates containing various chiral moieties
Authors: Liu Jui‐Hsiang , Hung Hsien‐Jung , Yang Po‐Chih , Tien Kai‐Hsin
Published: August 2008

To investigate the effect of spacer length and linkages between the rigid mesogenic core and the terminal group on the molecular interaction and physical properties of polymers, two series of novel side chain liquid crystalline polyacrylates were synthesized. These were composed of liquid crystalline monomers with six or eleven methylene segments as spacers, and chiral monomers end capped with menthyl or cholesteryl groups. Liquid crystalline phases of the polymers were investigated using differential scanning calorimetry and polarized optical microscopy, and confirmed with X‐ray diffractometry. Color image recording of the synthesized polymer films was achieved using a thermal treatment, and then fixed by quenching. This investigation demonstrates that the introduction of carbonate linking groups between the rigid mesogenic core and terminal group decreases both the lateral molecular interaction and thermal stability of the liquid crystalline polymers. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 6214–6228, 2008
Thermal treatment of dense polyimide membranes
Authors: Duthie X. , Kentish S. , Pas S. J. , Hill A. J. , Powell C. , Nagai K. , Stevens G. , Qiao G.
Published: August 2008

A study has been conducted to clarify the relationship between polymer structure, annealing temperature, and the extent of plasticization by high‐pressure CO2 for two typical polyimide membranes; BTDA‐DAPI (poly(3,3′‐4,4′‐benzophenone tetracarboxylic–dianhydride diaminophenylindane) and 6FDA‐TMPDA (poly(2,2′‐bis(3,4′‐dicasrboxyphenyl) hexafluoropropane dianhydride–2,3,5,6‐tetramethyl‐1,4‐phenylenediamine). Both membrane materials are exposed to varying levels of thermal annealing at 200 and 250 °C. The effect of this heat treatment on free volume is examined using positron annihilation lifetime spectroscopy (PALS), whereas fluorescence spectroscopy is used to monitor changes in electronic structure. Results show that thermal annealing causes a reduction in both the size and number of free volume elements. A strong relationship is found between the fluorescence peak intensity for 6FDA‐TMPDA and both the membrane gas permeability and plasticization pressure. This correlation is most likely the result of the formation of charge transfer complexes, particularly at 250 °C. However, the formation of covalent crosslinks at these temperatures cannot be discounted. No fluorescence is observed for BTDI‐DAPI. Although thermal annealing has a significant effect on the extent of plasticization in both polymers, it is found that the rate of plasticization is unaffected by the annealing temperature. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 1879–1890, 2008
Characterization of the stable and metastable poly(ethylene oxide)–urea complexes in electrospun fibers
Authors: Liu Yang , Antaya Hélène , Pellerin Christian
Published: August 2008

Solution electrospinning was used for the first time to prepare nanofibers of the stable (α) and metastable (β) complexes between poly(ethylene oxide) (PEO) and urea. Both types of fibers were highly crystalline and presented a large level of molecular orientation. Detailed characterization of the ill‐studied β complex was performed using wide angle X‐ray diffraction (WAXD), infrared spectroscopy, and differential scanning calorimetry (DSC). Results reveal that it possesses a 3:2 PEO:urea stoichiometry and suggest that it belongs to the orthorhombic system with a = 1.907 nm, b = 0.862 nm, and c = 0.773 nm. The PEO chains are oriented along the fiber axis and present a conformation significantly affected by strong hydrogen bonding with urea when compared with the pure polymer and the stable complex. A layered structure model is suggested for the metastable complex, in which the urea molecules would be arranged into a ribbon‐like structure intercalated between two PEO layers. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 1903–1913, 2008
Synthesis and optoelectronic characterization of poly(fluorenylethynylene)s containing perylene bisimide moiety in the backbone
Authors: Wang Hong‐Yu , Peng Bo , Wei Wei
Published: August 2008

A series of poly(fluorenylethynylene)s containing different ratios of perylene bisimide moiety in the backbone were synthesized by Sonogashira cross‐coupling reaction. The electron‐deficient perylene bisimide moiety was introduced into the backbone to construct the donor‐acceptor architectures. The chemical structures of these copolymers were determined by 1H NMR and FTIR. The solubility, thermal, and optoelectronic properties were studied. The results of UV–vis absorption and fluorescence spectra of these copolymers showed that intramolecular energy transfer and charge separation occur between the fluorenyl alkyne segment and perylene bisimide moiety. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 1932–1938, 2008
The relationship between chondroprotective and antiinflammatory effects of Withania somnifera root and glucosamine sulphate on human osteoarthritic cartilage in vitro
Authors: Sumantran Venil N. , Chandwaskar Rucha , Joshi Asavari Kulkarni , Boddul Sanjay , Patwardhan Bhushan , Chopra Arvind , Wagh Ulhas V.
Published: August 2008

Using a validated explant model of in vitro cartilage damage, the effects of aqueous extracts of Withania somnifera (Ashwagandha) root and glucosamine sulphate (GlcS) were tested on the levels of nitric oxide (NO) and glycosaminoglycans (GAGs) secreted by knee cartilage from chronic osteoarthritis (OA) patients. W. somnifera extracts significantly decreased NO release by explants from one subset of patients (antiinflammatory response) and significantly increased levels of NO and GAGs released by explants from the second subset (‘non‐responders’). This is the first study showing direct, statistically significant, antiinflammatory effects of W. somnifera on human OA cartilage. It also confirmed that glucosamine sulphate exhibited statistically significant, antiinflammatory and chondroprotective activities in human OA cartilage. However, these beneficial effects of GlcS were observed in cartilage explants from 50% of patients tested (‘responders’). In contrast, glucosamine significantly increased secretion of NO but not GAGs in explants from the second subset of OA patients (‘non‐responders’). Cartilage explants from the 11 OA patients gave differential responses to both drugs. Patient samples which responded to the antiinflammatory effects of W. somnifera did not always give a similar response to glucosamine, and vice versa. Thus, this in vitro model of human cartilage damage provides qualitative and statistically significant, quantitative pre‐clinical data on antiinflammatory and chondroprotective activities of antiarthritic drugs. Copyright © 2008 John Wiley & Sons, Ltd.
Omega‐3 fatty acid deficiency augments amphetamine‐induced behavioral sensitization in adult DBA/2J mice: Relationship with ventral striatum dopamine concentrations
Authors: McNamara Robert K. , Sullivan Juliana , Richtand Neil M. , Jandacek Ronald , Rider Therese , Tso Patrick , Campbell Nick , Lipton Jack
Published: August 2008

The principal polyunsaturated fatty acid acids found in brain, arachidonic acid (AA) and docosahexaenoic acid (DHA), preferentially accumulate in synaptic membranes. Although neurochemical studies have found that dietary‐induced deficits in rat brain DHA composition significantly alter mesocorticolimbic dopamine (DA) neurotransmission, its impact on DA‐mediated behavior remains poorly understood. In the present study, we determined the effects of dietary‐induced deficits in brain DHA composition on amphetamine (AMPH)‐induced locomotor activity and sensitization in DBA/2J mice, an inbred strain previously found to be hyporesponsive to AMPH, as well as monoamine concentrations in the PFC and ventral striatum following the AMPH challenge. Chronic dietary ω‐3 fatty acid deficiency significantly decreased PFC (−25%) and ventral striatum (−20%) DHA composition, increased PFC (+7%) and ventral striatum (+6%) AA composition, and increased the AA:DHA ratio in PFC (+30%) and ventral striatum (+24%). The development and expression of AMPH‐induced sensitization was significantly increased in DHA‐deficient mice, whereas novelty‐ and acute AMPH‐induced locomotor activity were not altered. DHA‐deficient mice exhibited significantly greater ventral striatum, but not PFC, DA and DA metabolite concentrations following the AMPH challenge, whereas serotonin and noradrenalin concentrations were not altered. Ventral striatum AA composition and the AA:DHA ratio were both positively correlated with DA concentrations, and both ventral striatum AA composition and DA concentrations were positively correlated with locomotor activity during the preceding AMPH challenge. These results demonstrate that dietary‐induced brain DHA deficiency, and associated elevation in the AA:DHA ratio, augment AMPH‐induced sensitization in DBA/2J mice, and that this augmented response is associated with selective alterations in the mesolimbic DA pathway. Synapse 62:725–735, 2008. © 2008 Wiley‐Liss, Inc.
Differences in aggressive behavior and in the mesocorticolimbic DA system between A/J and BALB/cJ mice
Authors: Couppis Maria H. , Kennedy Craig H. , Stanwood Gregg D.
Published: August 2008

The neurotransmitters DA and serotonin are known to be important modulators of aggression, but endogenous differences in these systems between aggressive and nonaggressive animals are poorly understood. To examine this issue, the mesocorticolimbic DA and serotonin systems of two mouse strains that differ in aggressive behavior, BALB/cJ and A/J, were analyzed using high performance liquid chromatography and quantitative receptor autoradiography. Significant differences in both serotonergic and dopaminergic systems were found between aggressive and nonaggressive mice. The nonaggressive A/J mice exhibited higher DA utilization in the nucleus accumbens and prefrontal cortex, higher D1 receptor expression in the rostral pole of the accumbens, and lower D2 receptor expression throughout the accumbens, as compared with aggressive BALB/cJ mice. Although correlative in nature, these data suggest that differences in mesocorticolimbic DA and serotonin systems may contribute to endogenous differences in aggression. Synapse 62:715–724, 2008. © 2008 Wiley‐Liss, Inc.
Repeated morphine exposure decreased the nucleus accumbens excitability during short‐term withdrawal
Authors: Heng Li‐Jun , Yang Jing , Liu Yi‐Hui , Wang Wen‐Ting , Hu San‐Jue , Gao Guo‐Dong
Published: August 2008

It is well known that the nucleus accumbens plays an important role in drug reinforcing effect and relapse. However, the cellular neuroadaptations that take place in accumbens neurons after repeated drug exposure are still not well understood, especially for opioids. Here, we examined how nucleus accumbens neuronal excitability becomes affected in rats exposed to morphine using whole‐cell patch‐clamp recordings. Medium spiny neurons recorded from brain slices of repeated morphine treated rats exhibited a significant decrease in the intrinsic excitability after 3–4 days withdrawal, compared to that of neurons from saline treated animals, which was indicated by the increase of current to evoke the first spike and the decrease of spike number induced by depolarizing current steps in the morphine group. Moreover, the excitability decrease was accompanied by related membrane property changes, such as resting membrane potential hyperpolarization, input resistance, and membrane time constant decrease, inward rectification increase, and action potential duration decrease. Taken together, repeated morphine exposure and short‐term withdrawal may reduce nucleus accumbens activity and output by modulating intrinsic membrane properties of its output neurons, which could be an important neuroadaptation process that mediates morphine addictive effect. Synapse 62:775–782, 2008. © 2008 Wiley‐Liss, Inc.
Identification of the orotidine‐5′‐monophosphate decarboxylase gene of the oleaginous yeast Rhodosporidium toruloides
Authors: Yang Fan , Zhang Sufang , Tang Wei , Zhao Zongbao K.
Published: August 2008

Oleaginous yeast Rhodosporidium toruloides is an excellent microbial lipid producer of great industrial potential, yet there is no effective genetic tool for rationally engineering this microorganism. To develop a marker recycling system, the orotidine‐5′‐monophosphate (OMP) decarboxylase gene of R. toruloides (RtURA3) was isolated using methods of degenerate polymerase chain reaction (PCR) together with rapid amplification of cDNA ends. The results showed that RtURA3 contains four extrons and three introns, and that the encoded polypeptide holds a sequence of 279 amino acid residues with significant homology to those of OMP decarboxylases from other yeasts. A shuttle vector pYES2/CT–RtURA3 was constructed via site‐specific insertion of RtURA3 into the commercial vector pYES2/CT. Transformation of the shuttle vector into Saccharomyces cerevisiae BY4741, a URA3‐deficient yeast strain, ensured the viability of the strain on synthetic dextrose agar plate without uracil, suggesting that the isolated RtURA3 was functionally equivalent to the URA3 gene from S. cerevisiae. The GenBank Accession Nos for the cDNA and genomic DNA sequences of RtURA3 are EU693528 and EU693529, respectively. Copyright © 2008 John Wiley & Sons, Ltd.
Photosynthetic response of Fragaria orientalis in different water contrast clonal integration
Authors: Zhang Yunchun , Zhang Qiaoying , Luo Peng , Wu Ning
Published: August 2008

The capacity to exchange resources and non‐resource agents is one of the most outstanding features of clonal plants. Contrast between patches in a heterogeneous environment is the main external driving force behind integration effects. It was hypothesized, on the basis of the source–sink hypothesis, that assimilate demand from drought‐stressed ramets will result in enhancement of the photosynthesis of well‐watered ramets by a mechanism of feedback regulation, that the negative effect of drought on the photosynthesis of drought‐stressed ramets will be ameliorated by physiological integration, and that these effects will be enhanced by increasing contrast. A pot experiment was conducted with clonal fragments consisting of two interconnected ramets of Fragaria orientalis. In the experiment, both the connected and the disconnected clonal fragments were divided into three water contrast groups: (1) homogeneous (no contrast) group; (2) low‐contrast group; (3) high‐contrast group. The photosynthesis and stress tolerance of drought‐stressed ramets did not decrease under the support of well‐watered ramets when they were connected, allowing clones to maintain their performance in less favorable environments. But the photosynthesis and stress tolerance of drought‐stressed ramets decreased with increasing drought‐stress when stolons were disconnected. With a feedback regulation process, the photosynthesis of well‐watered ramets connected to drought‐stressed ramets was enhanced by the latter, which can compensate, at least partially, for the cost of maintaining the stressed ramets. Drought‐stressed ramets gained more benefits in a high‐contrast environment than in a lower‐contrast environment; this can enhance the survival of drought‐stressed ramets in unfavorable habitats, especially stressed patches that would otherwise be unexploitable by independent ramets. But photosynthesis of well‐watered ramets did not increase with increasing water availability contrast. It can be concluded that photosynthesis and stress tolerance of F. orientalis was affected by clonal integration and by contrasts of water availability.
Biological Functions and Metabolism of Oleoylethanolamide
Authors: Thabuis Clémentine , Tissot‐Favre Delphine , Bezelgues Jean‐Baptiste , Martin Jean‐Charles , Cruz‐Hernandez Cristina , Dionisi Fabiola , Destaillats Frédéric
Published: August 2008

The present review is focused on the metabolism and the emerging roles of oleoylethanolamide (OEA) with emphasis on its effects on food intake control and lipid metabolism. The biological mechanism of action, including a non‐genomic effect mediated through peroxisome proliferator‐activated receptor alpha (PPAR‐α) and transient receptor potential vanilloid type 1 (TRPV1) receptor, is discussed. The research related to fatty acid ethanolamides has been focused until recently on anandamide and its interaction with cannabinoid receptor subtype 1. The roles of other N‐acyl ethanolamine fatty acid derivatives have been neglected until it was demonstrated that OEA can modulate food intake control through interaction with PPAR‐α. Further investigations demonstrated that OEA modulates lipid and glucose metabolism, and recent study confirmed that OEA is an antagonist of TRVP1. It has been demonstrated that OEA has beneficial effects on health by inducing food intake control, lipid β‐oxidation, body weight loss and analgesic effects. The investigation of the mechanism of action revealed that OEA activates PPAR‐α and stimulates the vagal nerve through the capsaicin receptor TRPV1. Pre‐clinical studies showed that OEA remains active when administered orally.
Establishment and functional characterization of a tracheal epithelial cell line RTEC11 from transgenic rats harboring temperature‐sensitive simian virus 40 large T‐antigen
Authors: Tabuchi Yoshiaki , Doi Takeshi , Takasaki Ichiro , Takahashi Ri‐ichi , Ueda Masatsugu , Suzuki Yoshihisa , Obinata Masuo
Published: August 2008

A tracheal epithelial cell line RTEC11 was established from transgenic rats harboring temperature‐sensitive simian virus 40 large T‐antigen. The cells grew continuously at a permissive temperature of 33 °C but not at a non‐permissive temperature of 39 °C. Morphological and functional investigations demonstrated that the cells were polarized epithelial cells maintaining a regulated permeability barrier function. Interestingly, the expression levels of Muc1 (mucin 1) and Scgb1a1 (uteroglobin), non‐ciliated secretory cell markers, and Tubb4 (tubulin beta 4), a ciliated cell marker, were significantly increased under the cell growth‐restricted condition. Global gene expression and computational network analyses demonstrated a significant genetic network associated with cellular development and differentiation in cells cultured at the non‐permissive temperature. The tracheal epithelial cell line RTEC11 with unique characteristics should be useful as an in vitro model for studies of the physiological functions and gene expression of tracheal epithelial cells.
Contact effects of translation: Distinguishing two kinds of influence in Old English
Authors: Taylor Ann
Published: August 2008

Many of our surviving Old English (OE) texts are translations from Latin originals. Given that the syntax of Latin and OE differ in a number of ways, the possibility of transference in the process of translation is an important issue for studies of OE syntax. This article examines one syntactic structure where the syntax of the languages differ: the prepositional phrase (PP) with pronominal complement. In Latin, PPs with pronominal complements are essentially head-initial, while in OE they vary between head-initial and head-final. I show that two distinct translation effects can be distinguished, one direct and one indirect, and that these effects apply differentially to two different types of translation, biblical and nonbiblical. I relate these different translation effects to the different strategies of OE translators when faced with biblical and nonbiblical texts.
Morphosyntactic and phonological constraints on negative particle variation in French-language chat discourse
Authors: van Compernolle Rémi A.
Published: August 2008

This study investigates the variable presence or absence of the negative morphemenein online French-language chat environments. The data indicate an overwhelming preference for the omission ofnein most instances of verbal negation, which corroborates previous studies ofnein everyday conversational French. VARBRUL analyses revealed four principal results: (i) subject type (i.e., noun phrase [NP], pronoun, or inferred subject) is the most influential factor; (ii) NPs favornepresence irrespective of the conditioning factors considered in this study; (iii) the variable presence ofneis conditioned by phonological factors within the subject pronoun category; (iv) the type of second-negative present (i.e.,pasvs. second-negative other thanpas) influencesneretention in inferred subject environments.
Civil and Religious Law in England: A Religious Perspective
Authors: Williams Rowan
Published: August 2008

This is the complete text of the lecture delivered by the Archbishop of Canterbury at the Royal Courts of Justice on 7 February 2008, under the chairmanship of Lord Phillips of Worth Matravers, the Lord Chief Justice, as the Foundation Lecture in a series of public discussions on ‘Islam in English Law’.1 The lecture seeks to tease out some of the broader issues around the rights of religious groups within a secular state, using sharia as an example and noting the substantial difference between ‘primitivist’ accounts of sharia and those of serious jurists within Islam. The Archbishop discusses the implications of some interpretations of Western secular legal systems, which seek to remove from consideration the actual religious motivations and practices of groups in plural societies. Where the law does not take religious motivation seriously, then it fails to engage with the community in question and opens up real issues of power by the majority over the minority and thus of community cohesion. It examines whether there should be a higher level of attention to religious identity and communal rights in the practice of the law: how to manage the distinction between cultural practices and those arising from genuine religious belief; and what to do about the possibility that a supplementary jurisdiction could have the effect of reinforcing in minority communities some of the most repressive or retrograde elements in them, with particularly serious consequences for the role and liberties of women. Is a monopolistic approach to a legal system a satisfactory basis for a modern pluralistic and democratic state? Might there be room for ‘overlapping jurisdictions’, in which individuals can choose in certain limited areas whether to seek justice under one system or another? If we are to think intelligently about the relations between Islam and British law, we need a fair amount of ‘deconstruction’ of crude oppositions and mythologies, whether of the nature of sharia or of the nature of the Enlightenment. Following the text of the lecture is a transcript of the Question and Answer session which followed.
The Ninth Colloquium of Anglican and Roman Catholic Canon Lawyers
Authors: Hilbert Michael
Published: August 2008

The Ninth Colloquium of Anglican and Roman Catholic Canon Lawyers took place from 3 to 6 April 2008, at Bishop's House, Sliema, Malta, and the meeting was graciously hosted by the Anglican contingent. The ten participants (five Anglican and five Roman Catholic) were: on the Anglican side, Norman Doe (Chair), Bishop Paul Colton, Mark Hill, Anthony Jeremy (all from the Centre for Law and Religion at Cardiff Law School) and Stephen Slack (Director of Legal Services at the Archbishops' Council, Church of England); and, on the Roman Catholic side, James Conn, Michael Hilbert, Aidan McGrath (all from the Faculty of Canon Law at the Pontifical Gregorian University), Robert Ombres (Procurator General of the Dominicans) and Fintan Gavin.
Line-of-Sight Networks
Authors: FRIEZE ALAN , KLEINBERG JON , RAVI R. , DEBANY WARREN
Published: August 2008

Random geometric graphs have been one of the fundamental models for reasoning about wireless networks: one places n points at random in a region of the plane (typically a square or circle), and then connects pairs of points by an edge if they are within a fixed distance of one another. In addition to giving rise to a range of basic theoretical questions, this class of random graphs has been a central analytical tool in the wireless networking community.

For many of the primary applications of wireless networks, however, the underlying environment has a large number of obstacles, and communication can only take place among nodes when they are close in space and when they have line-of-sight access to one another – consider, for example, urban settings or large indoor environments. In such domains, the standard model of random geometric graphs is not a good approximation of the true constraints, since it is not designed to capture the line-of-sight restrictions.

Here we propose a random-graph model incorporating both range limitations and line-of-sight constraints, and we prove asymptotically tight results for k-connectivity. Specifically, we consider points placed randomly on a grid (or torus), such that each node can see up to a fixed distance along the row and column it belongs to. (We think of the rows and columns as ‘streets’ and ‘avenues’ among a regularly spaced array of obstructions.) Further, we show that when the probability of node placement is a constant factor larger than the threshold for connectivity, near-shortest paths between pairs of nodes can be found, with high probability, by an algorithm using only local information. In addition to analysing connectivity and k-connectivity, we also study the emergence of a giant component, as well an approximation question, in which we seek to connect a set of given nodes in such an environment by adding a small set of additional ‘relay’ nodes.
Wall shear rate in supra-aortic vessels: a factor for different atherosclerotic pattern?
Authors: Simon  , Spring  , Luechinger  , Boesiger  , Amann-Vesti
Published: August 2008

Background: Atherosclerotic lesions of the upper extremity arise three to five times more often at the origin of the left subclavian artery than on the right side. The aim of this study was to investigate, whether the hemodynamic forces (peak wall shear rate) in the large supra-aortic branches measured by MRI differ in healthy subjects. Patients and methods: Peak wall shear rate (WSR) and blood flow was assessed in the left carotid, left subclavian and innominate artery in ten healthy volunteers (5 females, mean age of 35.2 ± 9 years) using high resolution (pixel size 0.6 mm2) magnetic resonance imaging (MRI) flow velocity measurements. Results: There is no difference between the maximum WSR of the three large supra-aortic vessels. Only within the proximal (327 ± 132s-1) and distal wall (458 ± 154s-1) of the innominate artery a significant difference (p = 0.011) of the WSR was found. Conclusion: The results from this study indicate that WSR is not different in the supra-aortic vessels. Therefore the atherosclerotic pattern in the subclavian and innominate arteries may not be explained by differences in these hemodynamic forces.
Oral sirolimus for prevention of recurrent infrainguinal arterial obstructions after surgical and endovascular revascularizations
Authors: Keo  , Do  , Husmann  , Baumgartner
Published: August 2008

No data are currently available on the role of oral sirolimus in the prevention of recurrent stenosis in the periphery. We report the effects of oral sirolimus in the prevention of recurrent infrainguinal obstructions in patients with complex peripheral arterial disease. Three patients with ischemic rest pain of the lower limbs and repeated short-term need for surgical and/or endovascular revascularization: 9 times within 12 months, 7 times within 15 months, 11 times within 26 months, respectively. Oral sirolimus on a case by case basis, resulted in less frequent restenosis and longer intervention-free intervals: three re-interventions within 37 months in the first patient, one balloon angioplasty within 17 months in the second, and three re-interventions within 21 months in the third patient, respectively. Side effects, in particular dyspepsia and diarrhoea, were mild and tolerable. To our knowledge, this is the first report to show that oral sirolimus was successfully administered in patients with recurrent excessive neointimal proliferation after revascularization of peripheral arterial lesions lowering the necessity of re-intervention and hence prolonging intervention-free intervals.
Fieber und Gewichtsverlust nach BCG-Instillation in die Harnblase bei Urothelkarzinom
Authors: Piso R.J. , Toniolo M.
Published: August 2008

Wir berichten über einen Patienten, welcher nach der vierten BCG-Instillation in die Harnblase bei Urothel-Karzinom akut unter einer BCG-Pneumonitis erkrankte. Im Thoraxröntgenbild präsentierte sich eine bilaterale retikulonoduläre Transparenzminderung. Mycobacterium tuberculosis konnte weder in der Kultur, noch in Biopsien oder der PCR nachgewiesen werden. Unter der Dreiertherapie mit Rifampicin, Isoniazid und Ethambutol wurde der Patient in kurzer Zeit beschwerdefrei und der Röntgenbefund normalisierte sich. Auf eine zusätzliche Steroidtherapie konnte verzichtet werden.
Can core‐surface flow models be used to improve the forecast of the Earth's main magnetic field?
Authors: Maus Stefan , Silva Luis , Hulot Gauthier
Published: August 2008

Geomagnetic main field models used for navigation are updated every 5 years and contain a forecast of the geomagnetic secular variation for the upcoming epoch. Forecasting secular variation is a difficult task. The change of the main magnetic field is thought to be principally due to advection of the field by flow at the surface of the outer core on short timescales and when large length scales are considered. With accurate secular variation (SV) and secular acceleration (SA) models now available from new satellite missions, inverting for the flow and advecting it forward could lead to a more accurate prediction of the main field. However, this scheme faces two significant challenges. The first arises from the truncation of the observable main field at spherical harmonic degree 13. This can however be handled if the true core flow is large scale and has a rapidly decaying energy spectrum. The second is that even at a given single epoch the instantaneous SV and SA cannot simultaneously be explained by a steady flow. Nevertheless, we find that it may be feasible to use flow models for an improved temporal extrapolation of the main field. A medium‐term (≈10 years) hindcast of the field using a steady flow model outperforms the usual extrapolation using the presently observed SV and SA. On the other hand, our accelerated, toroidal flow model, which explains a larger portion of the observed average SA over the 2000–2005 period, fails to improve both the short‐term and medium‐term hindcasts of the field. This somewhat paradoxical result is related to the occurrence of so‐called geomagnetic jerks, the still poorly known dynamical nature of which remains the main obstacle to improved geomagnetic field forecasts.
The role of crustal strength variations in shaping orogenic plateaus, with application to Tibet
Authors: Cook Kristen L. , Royden Leigh H.
Published: August 2008

The Tibetan Plateau is the type example of a large orogenic plateau formed as a result of continent‐continent collision. The morphology of the plateau and its margins suggests that preexisting variations in crustal strength have influenced the growth of the plateau. We have developed a three‐dimensional numerical model of deformation in a viscous crust in order to investigate the effects of lateral heterogeneities on plateau growth. The model includes a two layer crust and allows for lateral variation of viscosity in both the upper and lower layers. Model results indicate that crustal strength variations have a dramatic effect on the morphology and dynamics of a developing plateau. A region of strong crust is characterized by a very steep plateau margin that propagates extremely slowly, does not accommodate significant shortening strain, and is subparallel to local upper and lower crustal velocities. A weak crustal region develops a gently sloping margin; uplift propagates rapidly across the weak zone, and crustal material within the plateau is diverted toward the low‐strength region. With a relatively simple distribution of strength variations, corresponding to strong Tarim and Sichuan Basin crust and a weak southeastern corner, our model produces a plateau with many similarities to the Tibetan Plateau, including the overall morphology, rotation around the eastern syntaxis, and E–W extension. Analysis of model results suggests that E–W extension of the central plateau may be related to the rapid eastward flow of crustal material into a weak zone in the SE corner without significant change in plateau elevation.
Effects of the Phoenix Lander descent thruster plume on the Martian surface
Authors: Plemmons D. H. , Mehta M. , Clark B. C. , Kounaves S. P. , Peach L. L. , Renno N. O. , Tamppari L. , Young S. M. M.
Published: August 2008

The exhaust plume of Phoenix's hydrazine monopropellant pulsed descent thrusters will impact the surface of Mars during its descent and landing phase in the northern polar region. Experimental and computational studies have been performed to characterize the chemical compounds in the thruster exhausts. No undecomposed hydrazine is observed above the instrument detection limit of 0.2%. Forty‐five percent ammonia is measured in the exhaust at steady state. Water vapor is observed at a level of 0.25%, consistent with fuel purity analysis results. Moreover, the dynamic interactions of the thruster plumes with the ground have been studied. Large pressure overshoots are produced at the ground during the ramp‐up and ramp‐down phases of the duty cycle of Phoenix's pulsed engines. These pressure overshoots are superimposed on the 10 Hz quasi‐steady ground pressure perturbations with amplitude of about 5 kPa (at touchdown altitude) and have a maximum amplitude of about 20–40 kPa. A theoretical explanation for the physics that causes these pressure perturbations is briefly described in this article. The potential for soil erosion and uplifting at the landing site is also discussed. The objectives of the research described in this article are to provide empirical and theoretical data for the Phoenix Science Team to mitigate any potential problem. The data will also be used to ensure proper interpretation of the results from on‐board scientific instrumentation when Martian soil samples are analyzed.
An Antarctica‐to‐Spain HF ionospheric radio link: Sounding results
Authors: Vilella C. , Miralles D. , Pijoan J. L.
Published: August 2008

Our research group in Electromagnetism and Communications is involved in a project dealing with the channel characterization of an ionospheric radio link from the Spanish Antarctic Base (62.6°S, 60.4°W) to the Observatori de l'Ebre (40.8°N, 0.5°E) in Spain. Since the link was established for the first time on December 2003, the sounder and measurement techniques have been improved on the basis of the preliminary results. In this paper, the final results of the project corresponding to the 2006/2007 sounding survey are presented. First the hardware and measurement techniques used to probe the channel are described. Then the results in terms of channel availability (and its daily, hourly, and frequency variation), multipath and Doppler spreads, and signal‐to‐noise ratio are discussed. These results are being used to design the physical layer of a low data rate transmission system intended to send the information acquired by a geomagnetic sensor in the Antarctica.
Contaminated Rivers: A Geomorphological‐Geochemical Approach to Site Assessment and Remediation
Authors: Meybeck Michel
Published: August 2008

Rivers, over time subjected to multiple uses by humans, are integrators of human impacts on the Earth system. As a result, the hydrological, geomorphological, geochemical, and ecological characteristics of rivers have been gradually, or suddenly, changed over time, depending on human pressures. Multiple symptoms of river changes are readily observable at the global scale as bacterial contamination, organic pollution, eutrophication, hydrological regime modifications and related impacts on the aquatic habitat, changes in sediment transport regimes and their related impacts on river morphology, and toxic substance occurrence in the riverine environment. This book makes a combined analysis of these last two issues, particularly concerning the toxic metals mercury, zinc, cadmium, and lead.
On the importance of midlatitude oceanic frontal zones for the mean state and dominant variability in the tropospheric circulation
Authors: Nakamura Hisashi , Sampe Takeaki , Goto Atsushi , Ohfuchi Wataru , Xie Shang‐Ping
Published: August 2008

Observations indicate that midlatitude weather systems are organized into “storm tracks” near oceanic frontal zones with pronounced sea‐surface temperature (SST) gradients. A pair of atmospheric general circulation model experiments with zonally uniform SST profiles prescribed show that their observed collocation is not fortuitous. In one experiment, a storm track is anchored around a midlatitude SST front that maintains near‐surface thermal gradients and energizes eddies. Westerly momentum transport by eddies produces a well‐defined polar‐front jet along the front, even in winter when a subtropical jet stream intensifies. In the other experiment, removal of the SST front leads to a substantial weakening in eddy activity and the PFJ especially in winter. It also leads to a weakening of the annular mode —the dominant mode of westerly‐jet variability— and its notable structural distortion in winter. Though idealized, our experiments suggest the importance of midlatitude oceanic fronts for the tropospheric circulation and its variability.
Aerial infrared imaging reveals large nutrient‐rich groundwater inputs to the ocean
Authors: Johnson Adam G. , Glenn Craig R. , Burnett William C. , Peterson Richard N. , Lucey Paul G.
Published: August 2008

Regional high‐resolution (0.1°C, 0.5 m) low‐altitude thermal infrared imagery (TIR) reveals the exact input locations and fine‐scale mixing structure of massive, cool groundwaters that discharge into the coastal zone as both diffuse flows and as >30 large point‐sourced nutrient‐rich plumes along the dry western half of the large volcanic island of Hawaii. These inputs are the sole source of new nutrient delivery to coastal waters in this oligotrophic setting. Water column profiling and nutrient sampling show that the plumes are cold, buoyant, nutrient‐rich brackish mixtures of groundwater and seawater. By way of example, we illustrate in detail one of the larger plumes, which discharges ca. 12,000 m3 d−1 (ca. 8,600 m3 d−1 freshwater), rates comparable in volume to high‐flux groundwater outputs in better‐known tropical karst terrains. We further show how nutrient mixing trends may be integrated into TIR sea surface temperatures to produce surface water nutrient maps of regional extent.
Enzymes or redox couples? The kinetics of thioredoxin and glutaredoxin reactions in a systems biology context
Authors: Pillay Ché S. , Hofmeyr Jan-Hendrik S. , Olivier Brett G. , Snoep Jacky L. , Rohwer Johann M.
Published: August 2008

Systems biology approaches, such as kinetic modelling, could provide valuable insights into how thioredoxins, glutaredoxins and peroxiredoxins (here collectively called redoxins), and the systems that reduce these molecules are regulated. However, it is not clear whether redoxins should be described as redox couples (with redox potentials) or as enzymes (with Michaelis–Menten parameters) in such approaches. We show that in complete redoxin systems, redoxin substrate saturation and other purported enzymatic behaviours result from limitations in the redoxin redox cycles in these systems. Michaelis–Menten parameters are therefore inappropriate descriptors of redoxin activity; data from redoxin kinetic experiments should rather be interpreted in terms of the complete system of reactions under study. These findings were confirmed by fitting kinetic models of the thioredoxin and glutaredoxin systems to in vitro datasets. This systems approach clarifies the inconsistencies with the descriptions of redoxins and emphasizes the roles of redoxin systems in redox regulation.
Protein partners of deubiquitinating enzymes
Authors: Ventii Karen H. , Wilkinson Keith D.
Published: August 2008

Protein modification by ubiquitin and ubiquitin-like molecules is a critical regulatory process. Like most regulated protein modifications, ubiquitination is reversible. Deubiquitination, the reversal of ubiquitination, is quickly being recognized as an important regulatory strategy. Nearly one hundred human DUBs (deubiquitinating enzymes) in five different gene families oppose the action of several hundred ubiquitin ligases, suggesting that both ubiquitination and its reversal are highly regulated and specific processes. It has long been recognized that ubiquitin ligases are modular enzyme systems that often depend on scaffolds and adaptors to deliver substrates to the catalytically active macromolecular complex. Although many DUBs bind ubiquitin with reasonable affinities (in the nM to μM range), a larger number have little affinity but exhibit robust catalytic capability. Thus it is apparent that these DUBs must acquire their substrates by binding the target protein in a conjugate or by associating with other macromolecular complexes. We would then expect that a study of protein partners of DUBs would reveal a variety of substrates, scaffolds, adaptors and ubiquitin receptors. In the present review we suggest that, like ligases, much of the regulation and specificity of deubiquitination arises from the association of DUBs with these protein partners.
Metabolic control of transcription: paradigms and lessons from Saccharomyces cerevisiae
Authors: Campbell Robert N. , Leverentz Michael K. , Ryan Louise A. , Reece Richard J.
Published: August 2008

The comparatively simple eukaryote Saccharomyces cerevisiae is composed of some 6000 individual genes. Specific sets of these genes can be transcribed co-ordinately in response to particular metabolic signals. The resultant integrated response to nutrient challenge allows the organism to survive and flourish in a variety of environmental conditions while minimal energy is expended upon the production of unnecessary proteins. The Zn(II)2Cys6 family of transcriptional regulators is composed of some 46 members in S. cerevisiae and many of these have been implicated in mediating transcriptional responses to specific nutrients. Gal4p, the archetypical member of this family, is responsible for the expression of the GAL genes when galactose is utilized as a carbon source. The regulation of Gal4p activity has been studied for many years, but we are still uncovering both nuances and fundamental control mechanisms that impinge on its function. In the present review, we describe the latest developments in the regulation of GAL gene expression and compare the mechanisms employed here with the molecular control of other Zn(II)2Cys6 transcriptional regulators. This reveals a wide array of protein–protein, protein–DNA and protein–nutrient interactions that are employed by this family of regulators.
Cardiovascular effects of air pollution
Authors: Brook Robert D.
Published: August 2008

Air pollution is a heterogeneous mixture of gases, liquids and PM (particulate matter). In the modern urban world, PM is principally derived from fossil fuel combustion with individual constituents varying in size from a few nanometres to 10 μm in diameter. In addition to the ambient concentration, the pollution source and chemical composition may play roles in determining the biological toxicity and subsequent health effects. Nevertheless, studies from across the world have consistently shown that both short- and long-term exposures to PM are associated with a host of cardiovascular diseases, including myocardial ischaemia and infarctions, heart failure, arrhythmias, strokes and increased cardiovascular mortality. Evidence from cellular/toxicological experiments, controlled animal and human exposures and human panel studies have demonstrated several mechanisms by which particle exposure may both trigger acute events as well as prompt the chronic development of cardiovascular diseases. PM inhaled into the pulmonary tree may instigate remote cardiovascular health effects via three general pathways: instigation of systemic inflammation and/or oxidative stress, alterations in autonomic balance, and potentially by direct actions upon the vasculature of particle constituents capable of reaching the systemic circulation. In turn, these responses have been shown to trigger acute arterial vasoconstriction, endothelial dysfunction, arrhythmias and pro-coagulant/thrombotic actions. Finally, long-term exposure has been shown to enhance the chronic genesis of atherosclerosis. Although the risk to one individual at any single time point is small, given the prodigious number of people continuously exposed, PM air pollution imparts a tremendous burden to the global public health, ranking it as the 13th leading cause of morality (approx. 800000 annual deaths).
What Do People Who Stutter Want—Fluency or Freedom?
Authors: Venkatagiri H. S.
Published: August 2008

Purpose

In this study, the author examined the following questions: What proportion of adult persons who stutter (PWS) choose fluency and what proportion choose to be free from a need to be fluent in managing their stuttering? What demographic and stuttering-related variables influence their choice, and how consistent are they in their choice?

Method

A survey instrument administered over the Internet was used to collect the data.

Results

Overall, 8% more of the 216 respondents opted for fluency than freedom. A larger proportion of male PWS and PWS under the age of 30 years preferred fluency. Neither nationality nor language background influenced their preference. Those who received no therapy overwhelmingly chose fluency, and a slight majority of those with fewer than 5 years of therapy preferred fluency. Those with more than 5 years of therapy were evenly divided between the 2 choices. Those who preferred freedom were more consistent in their responses across items than were those who opted for fluency. Based on the consistency of responses, 20% and 23% of the sample decisively opted for fluency and freedom, respectively, and 34% in the fluency group and 23% in the freedom group were ambivalent.

Conclusion

A majority of PWS appear to benefit from flexible treatment programs with cafeteria-style choices.