bluuebunny/crossref_metadata_2025 huggingface dataset:
A Strategy to Improve the Overall Performance of the Lithium Ion‐Conducting Solid Electrolyte Li0.36La0.56□0.08Ti0.97Al0.03O3
Authors: Wang Yaoming , Liu Zhanqiang , Huang Fuqiang , Yang Jianhua , Sun Junkang
Published: November 2008

A strategy to improve the overall performance of the lithium ion‐conducting solid electrolyte (Li‐CSE) Li0.36La0.56□0.08Ti0.97Al0.03O3 (LLTO) is proposed. Thin layers of the electronically insulating, electrochemically stable, and low‐melting Li‐CSE Li3.25Ge0.25P0.75S4 (LGPS) were coated onto LLTO powders, which resulted in oxide/sulfide composite electrolytes. The introduction of LGPS simultaneously brought about drastic reductions in the activation energies and great enhancements of the total ionic conductivities of the composite electrolytes. As the LGPS content was increased from 0 mol‐% to 20 mol‐%, the activation energy decreased steadily from 0.62 eV to 0.34 eV, and accordingly a total ionic conductivity as high as 1.62 × 10–4 S cm–1 was reached, almost the same as those of the excellent oxide‐based Li‐CSE ceramics sintered at extremely high temperatures, and a wide electrochemical window of over 6 V vs. Li+/Li was achieved. In addition, a low electronic conductivity of 2.38 × 10–9 S cm–1 at room temperature for the composite electrolyte was discovered.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Modular Spiro Bidentate Nitrogen Ligands – Synthesis, Resolution and Application in Asymmetric Catalysis
Authors: Sala Xavier , García Suárez Eduardo J. , Freixa Zoraida , Benet‐Buchholz Jordi , van Leeuwen Piet W. N. M.
Published: November 2008

A family of new modular, chiral, bidentate, nitrogen‐donor ligands containing the large spirobi(chroman) backbone 1 (SPAN) has been prepared. Enantiopure diamines containing the nitrogen donors at the 8,8′ positions of spirobi(chroman) 1 have been synthesized through the resolution of the 8,8′‐diamino racemate 3. Accordingly, secondary and tertiary amines [(+)‐6/(–)‐6 and (+)‐5/(–)‐5, respectively] and imino derivatives [(+)‐7/(–)‐7] were obtained in both enantiomeric forms. A new SPAN derivative incorporating aldehyde groups at the 8,8′ positions of the spirobi(chroman) unit [(+)‐9/(–)‐9] has been synthesized with the aim to extend the ligand library by means of Schiff base chemistry. The derivatization of the isolated enantiomers of 9 obtained by diastereomer resolution gave derivatives containing the nitrogen atoms at the benzylic positions. The syntheses of ligands (+)‐10/(–)‐10, (+)‐11 and (+)‐12 illustrate the scope of this methodology. The coordination ability of ligand (–)‐3 has been tested by the synthesis and characterization of complex [Pd(OAc)2{(–)‐3}] [(–)‐13]. Some preliminary results related to the oxidative kinetic resolution of 1‐phenylethanol with this Pd complex are reported.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Incremental dynamic analysis with consideration of modeling uncertainties
Authors: Dolsek Matjaz
Published: November 2008

Incremental dynamic analysis (IDA) has been extended by introducing a set of structural models in addition to the set of ground motion records which is employed in IDA analysis in order to capture record‐to‐record variability. The set of structural models reflects epistemic (modeling) uncertainties, and is determined by utilizing the latin hypercube sampling (LHS) method. The effects of both aleatory and epistemic uncertainty on seismic response parameters are therefore considered in extended IDA analysis. The proposed method has been applied to an example of the four‐storey‐reinforced concrete frame, for which pseudo‐dynamic tests were performed at the ELSA Laboratory, Ispra. The influence of epistemic uncertainty on the seismic response parameters is presented in terms of summarized IDA curves and dispersion measures. The results of extended IDA analysis are compared with the results of IDA analysis, and the sensitivity of the seismic response parameters to the input random variable using the LHS method is discussed. It is shown that epistemic uncertainty does not have significant influence on the seismic response parameters in the range far from collapse, but could have a significant influence on collapse capacity. Copyright © 2008 John Wiley & Sons, Ltd.
Involvement of eukaryotic translation initiation factor 5A (eIF5A) in skeletal muscle stem cell differentiation
Authors: Luchessi Augusto D. , Cambiaghi Tavane D. , Hirabara Sandro M. , Lambertucci Rafael H. , Silveira Leonardo R. , Baptista Igor L. , Moriscot Anselmo S. , Costa‐Neto Claudio M. , Curi Rui
Published: November 2008

The eukaryotic translation initiation factor 5A (eIF5A) contains a special amino acid residue named hypusine that is required for its activity, being produced by a post‐translational modification using spermidine as substrate. Stem cells from rat skeletal muscles (satellite cells) were submitted to differentiation and an increase of eIF5A gene expression was observed. Higher content of eIF5A protein was found in satellite cells on differentiation in comparison to non‐differentiated satellite cells and skeletal muscle. The treatment with N1‐guanyl‐1,7‐diaminoheptane (GC7), a hypusination inhibitor, reversibly abolished the differentiation process. In association with the differentiation blockage, an increase of glucose consumption and lactate production and a decrease of glucose and palmitic acid oxidation were observed. A reduction in cell proliferation and protein synthesis was also observed. L‐Arginine, a spermidine precursor and partial suppressor of muscle dystrophic phenotype, partially abolished the GC7 inhibitory effect on satellite cell differentiation. These results reveal a new physiological role for eIF5A and contribute to elucidate the molecular mechanisms involved in muscle regeneration. J. Cell. Physiol. 218: 480–489, 2009. © 2008 Wiley‐Liss, Inc.
Periostin‐like‐factor in osteogenesis
Authors: Zhu Shimei , Barbe Mary F. , Liu Cheng , Hadjiargyrou Michael , Popoff Steven N. , Rani Shobha , Safadi Fayez F. , Litvin Judith
Published: November 2008

Periostin‐like‐factor (PLF), an isoform related to Periostin, is expressed in bone, heart, and vascular smooth muscle cells. PLF was detected by immunostaining in mesenchymal cells in the periosteum and in osteoblasts lining trabecular bone, suggesting that PLF has a role in osteogenesis. PLF has a signal peptide and is also secreted from osteoblasts in vitro. To study the function of PLF in osteogenesis, we assessed the effect of PLF on osteoblast proliferation and differentiation in vitro and bone formation in vivo. First, to examine whether PLF regulates osteoblast proliferation in vitro, the CyQUANT cell proliferation assay was performed. PLF over‐expression by adenovirus resulted in a significantly higher rate of cell proliferation compared to controls. This finding suggests that PLF promotes osteoblast proliferation in vitro. Second, to test whether PLF mediates osteoblast differentiation in vitro, differentiation markers of osteoblasts, were assessed, including alkaline phosphatase staining and activity, von Kossa staining and calcium deposition. Over‐expression of PLF resulted in higher expression and activity of alkaline phosphatase and higher amounts of mineralization and calcium deposition compared to controls. These data suggest that PLF promotes osteoblast differentiation in vitro. Third, to investigate the role of PLF in bone formation in vivo, PLF adenovirus was injected into 6‐week‐old rat femur bone marrow. Over‐expression of PLF resulted in increased bone formation within the marrow cavity. Lastly, in a model of fracture healing, PLF expression is robustly upregulated in callus osteoblasts at post‐fracture days 7 and 14. Taken together, these findings suggests that PLF induces bone formation in vivo. We conclude that PLF stimulates bone formation in vivo possibly by promoting osteoblast proliferation and differentiation. J. Cell. Physiol. 218: 584–592, 2009. © 2008 Wiley‐Liss, Inc.
High fluence low‐power laser irradiation induces mitochondrial permeability transition mediated by reactive oxygen species
Authors: Wu Shengnan , Xing Da , Gao Xuejuan , Chen Wei R.
Published: November 2008

High fluence low‐power laser irradiation (HF‐LPLI) can induce cell apoptosis via the mitochondria/caspase‐3 pathway. Here, we further investigated the mechanism involved in the apoptotic process in human lung adenocarcinoma cells (ASTC‐a‐1) at a laser irradiation fluence of 120 J/cm2(633 nm). Cytochromecrelease was ascribed to mitochondrial permeability transition (MPT) because the release was prevented by cyclosporine (CsA), a specific inhibitor of MPT. Furthermore, mitochondrial permeability for calcein (∼620 Da) was another evidence for the MPT induction under HF‐LPLI treatment. A high‐level intracellular reactive oxygen species (ROS) generation was observed after irradiation. The photodynamically produced ROS caused onset of MPT, as the ROS scavenger docosahexaenoic acid (DHA) prevented the MPT. However, CsA failed to prevented cell death induced by HF‐LPLI, indicating the existence of other signaling pathways. Following laser irradiation, Bax activation occurred after mitochondrial depolarization and cytochromecrelease, indicating Bax activation was a downstream event. In the presence of CsA, Bax was still activated at the end‐stage of apoptotic process caused by HF‐LPLI, suggesting that Bax was involved in an alternative‐signaling pathway, which was independent of MPT. Under HF‐LPLI treatment, cell viabilities due to pre‐treatment with DHA, CsA, or Bax small interfering RNA (siRNA) demonstrated that the MPT signaling pathway was dominant, while Bax signaling pathway was secondary, and more importantly ROS mediated both pathways. Taken together, these results showed that HF‐LPLI induced cell apoptosis via the CsA‐sensitive MPT, which was ROS‐dependent. Furthermore, there existed a secondary signaling pathway through Bax activation. The observed link between MPT and triggering ROS could be a fundamental phenomenon in HF‐LPLI‐induced cell apoptosis. J. Cell. Physiol. 218: 603–611, 2009. © 2008 Wiley‐Liss, Inc.
By‐passing the nonsense mutation in the 4CV mouse model of muscular dystrophy by induced exon skipping
Authors: Mitrpant Chalermchai , Fletcher Sue , Iversen Patrick L. , Wilton Steve D.
Published: November 2008

Background

Duchenne muscular dystrophy (DMD), a severe neuromuscular disorder, is caused by protein‐truncating mutations in the dystrophin gene. Absence of functional dystrophin renders muscle fibres more vulnerable to damage and necrosis. We report antisense oligomer (AO) induced exon skipping in the B6Ros.Cg‐Dmdmdx–4Cv/J (4CV) mouse, a muscular dystrophy model arising from a nonsense mutation in dystrophin exon 53. Both exons 52 and 53 must be excised to remove the mutation and maintain the reading frame.

Methods

A series of 2′‐O‐methyl modified oligomers on a phosphorothioate backbone (2OMeAOs) were designed and evaluated for the removal of each exon, and the most effective compounds were then combined to induce dual exon skipping in both myoblast cultures and in vivo. Exon skipping efficiency of 2OMeAOs and phosphorodiamidate morpholino oligomers (PMOs) was evaluated both in vitro and in vivo at the RNA and protein levels.

Results

Compared to the original mdx mouse studies, induction of exon skipping from the 4CV dystrophin mRNA was far more challenging. PMO cocktails could restore synthesis of near‐full length dystrophin protein in cultured 4CV myogenic cells and in vivo, after a single intramuscular injection.

Conclusions

By‐passing the protein‐truncating mutation in the 4CV mouse model of muscular dystrophy could not be achieved with single oligomers targeting both exons and was only achieved after the application of AO cocktails to remove exons 52 and 53. As in previous studies, the stability and efficiency of PMOs proved superior to 2OMeAOs for consistent and sustained protein induction in vivo. Copyright © 2008 John Wiley & Sons, Ltd.
A Novel Thermoformable Bionanocomposite Based on Cellulose Nanocrystal‐graft‐Poly(ε‐caprolactone)
Authors: Chen Guangjun , Dufresne Alain , Huang Jin , Chang Peter R.
Published: November 2008

This is the first report on a thermoformable bionanocomposite based on a natural nanocrystal and formed by grafting long polymer chains onto the surface of microcrystalline cellulose. For the cellulose nanocrystal‐graft‐poly(ε‐caprolactone), the “graft from” strategy contributed to long and dense “plasticizing” PCL tails onto the CN surface as the key of thermoforming. The grafted PCL chains shielded the hydrophilic surface of CN and, hence, showed high water‐resistance. Moreover, a strategy for developing new bionanocomposite materials based on natural nanocrystals has been presented.

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Selective Localization and Migration of Multiwalled Carbon Nanotubes in Blends of Polycarbonate and Poly(styrene‐acrylonitrile)
Authors: Göldel Andreas , Kasaliwal Gaurav , Pötschke Petra
Published: November 2008

Multiwalled carbon nanotubes (MWNTs) have been introduced into blends of polycarbonate (PC) and poly(styrene‐acrylonitrile) (SAN) by melt mixing in a microcompounder. Co‐continuous blends are prepared by either pre‐compounding low amounts of nanotubes into PC or SAN or by mixing all three components together. Interestingly, in all blends, regardless of the way of introducing the nanotubes, the MWNTs were exclusively located within the PC phase, which resulted in much lower electrical resistivities as compared to PC or SAN composites with the same MWNT content. The migration of MWNTs from the SAN phase into the PC phase during common mixing is explained by interfacial effects.

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Similarities and differences between stockpiling and reference effects
Authors: Slonim Robert , Garbarino Ellen
Published: November 2008

The correlation of past prices and demand is commonly attributed to reference effects. Although reference dependence is robust, support for loss aversion is mixed; some find demand more sensitive to price increases, consistent with loss aversion, others find no difference or greater sensitivity to price decreases. Stockpiling offers an explanation for these mixed findings. Combining theory, analytical models and simulations, stockpiling and reference dependence predict similar effects and the more stockable the product, the greater sensitivity of demand to price decreases, the opposite of loss aversion. We show that a model combining stockpiling and reference effects best aligns with previous findings and under what conditions each effect should dominate. Copyright © 2008 John Wiley & Sons, Ltd.
PC2: A prognostic cloud fraction and condensation scheme. I: Scheme description
Authors: Wilson Damian R. , Bushell Andrew C. , Kerr‐Munslow Amanda M. , Price Jeremy D. , Morcrette Cyril J.
Published: November 2008

A prognostic cloud fraction and prognostic condensate scheme has been developed for the Met Office Unified Model. This is designed to replace the scheme currently used in weather forecast and climate simulations, in which cloud fraction and liquid water content are calculated diagnostically. Such a scheme overprescribes links between cloud fraction, condensate and water vapour contents. By contrast, our new prognostic cloud fraction and prognostic condensate scheme (PC2) calculates increments to prognostic variables of liquid, ice and total cloud fractions, water vapour and liquid condensate as a result of each physical process represented in the model. (Ice condensate is already represented prognostically.) This paper provides a summary of the PC2 scheme, describes how it is implemented, and discusses its relationship with other existing cloud schemes. Key aspects of the PC2 formulation are: the consistent derivation of prognostic terms, the reversible nature of the scheme under idealised forcing scenarios, the well‐behaved performance in the limit of very low and very high cloud fraction, the inclusion of ice microphysical processes, and the improved representation of cloud erosion processes. A companion paper presents the results from the scheme. © Crown Copyright 2008. Reproduced with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd.
TIGGE: Preliminary results on comparing and combining ensembles
Authors: Park Young‐Youn , Buizza Roberto , Leutbecher Martin
Published: November 2008

TIGGE, the THORPEX Interactive Grand Global Ensemble, is a World Weather Research Programme project to accelerate the improvements in the accuracy of 1‐day to 2‐week high‐impact weather forecasts. This report discusses some preliminary results from predictability studies based on the ensemble data exchanged within TIGGE, and available at the TIGGE archive centres. In the first part of this work, the key characteristics of the eight ensemble systems available in the TIGGE database at the time of writing (December 2007) are compared, and the strengths and weaknesses of each system are highlighted. Then, issues related to the generation of multi‐model/multi‐analysis ensemble products are discussed, and some preliminary results on the potential value of combining different ensembles to generate medium‐range products with a grand multi‐model/multi‐analysis global ensemble are presented.

One of the key results documented in this work is the large difference between the performance of the single ensembles: for Z500 over the Northern Hemisphere, in the medium‐range (say around forecast day 5), the difference between the worst and the best control or ensemble‐mean forecasts is about 2 days of predictability, while the difference between the worst and the best probabilistic predictions can be larger, about 3 days of predictability. Another key result has been the quantification of the difference between the skill of the best ensemble system and a combined ensemble generated considering up to four different ensemble systems. Results have indicated that the difference is very small in areas where the European Centre (EC) ensemble system has a well tuned ensemble spread, equivalent to less than 6 hours of predictability in the medium range, while it is larger and more detectable in areas where the EC system has a too low ensemble spread (e.g. in the Tropics). Copyright © 2008 Royal Meteorological Society
Development of redundant rigidity theory for formation control
Authors: Yu Changbin , Anderson Brian D. O.
Published: November 2008

Multiagent formation control may proceed by ensuring that designated pairs of agents maintain a specified distance between each other, in order that the overall shape of the formation can be preserved while it translates or rotates. A minimally rigid formation is one in which loss of any one such constraint or link means that individual agent motions can occur, which do not preserve the shape of the formation. Recognizing that real‐world formations may suffer link loss and even agent loss, this paper presents a systematic approach to defining a measure for redundant or nonminimal rigidity, which is the property that formation shape will still be preserved in the face of loss of a certain designated number of distance constraints or formation agents. Most of the results are concerned with advancing a deterministic measure, but this paper also indicates circumstances under which a statistical measure may be relevant. For illustration, the paper analyses a number of standard formations to establish their levels of redundancy. Copyright © 2008 John Wiley & Sons, Ltd.
Output feedback control design for station keeping of AUVs under shallow water wave disturbances
Authors: Liu Shuyong , Wang Danwei , Poh Engkee
Published: November 2008

In this paper, we consider the problem of autonomous underwater vehicle (AUV) station keeping (SK) in shallow water area. During SK, an AUV is required to maintain position and orientation with respect to a fixed reference point at the sea floor. When AUV operates in shallow water, high‐frequency disturbances due to waves will significantly affect the motion of the AUV. In order to derive wave disturbance information for control purposes, a nonlinear observer is first designed to estimate the shallow water wave velocities and AUV relative velocities by using position and attitude measurement. Using the observer estimates, a nonlinear output feedback controller is subsequently synthesized by applying observer backstepping technique. Global exponential stability (GES) of the proposed nonlinear observer–controller design is proved through Lyapunov stability theory. Simulation studies on a model based on an actual AUV were performed to verify the performance of the proposed nonlinear observer and output feedback controller. Copyright © 2008 John Wiley & Sons, Ltd.
Average consensus on networks with quantized communication
Authors: Frasca Paolo , Carli Ruggero , Fagnani Fabio , Zampieri Sandro
Published: November 2008

This work presents a contribution to the solution of the average agreement problem on a network with quantized links. Starting from the well‐known linear diffusion algorithm, we propose a simple and effective adaptation that is able to preserve the average of states and to drive the system near to the consensus value, when a uniform quantization is applied to communication between agents. The properties of this algorithm are investigated both by a worst‐case analysis and by a probabilistic analysis, and are shown to depend on the spectral properties of the evolution matrix. A special attention is devoted to the issue of the dependence of the performance on the number of agents, and several examples are given. Copyright © 2008 John Wiley & Sons, Ltd.
Fast Monitoring Proximity and Centrality on Time‐evolving Bipartite Graphs
Authors: Tong Hanghang , Papadimitriou Spiros , Yu Philip S. , Faloutsos Christos
Published: November 2008

Large bipartite graphs that evolve and grow over time (e.g. new links arrive, old links die out, or link weights change) arise in many settings, such as social networks, co‐citations, market‐basket analysis, and collaborative filtering.

How do we monitor (i) the centrality of an individual node (e.g. which is the most important conference), or (ii) the proximity of two nodes or sets of nodes (e.g. who are the most influential authors with respect to a particular conference)? How can we do this efficiently and incrementally? How can we provide ‘any‐time’ answers to interesting queries, with respect to node centrality or proximity?

In this paper we propose pTrack and cTrack, which are based on RWR, together with some important modifications to adapt these measures to a dynamic, evolving setting. Additionally, we develop techniques for fast, incremental updates of these measures that allow us to track them continuously as link updates arrive. In addition, we discuss variants of our method that can handle batch updates, as well as place more emphasis on recent links. We demonstrate the effectiveness and efficiency of our methods on several real datasets. Copyright © 2008 Wiley Periodicals, Inc. Statistical Analysis and Data Mining 1: 000‐000, 2008
Effect of Phenolic Compounds on the Pasting and Textural Properties of Wheat Starch
Authors: Zhu Fan , Cai Yi‐Zhong , Sun Mei , Corke Harold
Published: November 2008

Pasting and textural properties of wheat starch were systematically investigated in the presence of 25 phytochemicals including phenolic acids, flavonoids, coumarins, stillbenes and tannins with a wide structural diversity. Overall, most of these phenolic compounds significantly changed functional properties of starch. Trans‐cinnamic acid increased the peak viscosity most by 37 RVU whereas catechin decreased it most by 14 RVU. All the phenolic compounds considerably increased the breakdown with the greatest effect by chlorogenic acid (135 RVU) and the least by chrysin (6 RVU). Esculetin caused the maximum increase in setback (38 RVU), and 3‐hydroxybenzoic acid caused the maximum decrease (103 RVU). All the phenolic compounds significantly reduced the peak time with the greatest effect by trans‐cinnamic acid. Chrysin and 3‐hydroxybenzoic acid most increased and decreased the hardness of starch gels stored at 23°C for 48 h by 3.9 and 24.2 g. Most of the phenolic compounds increased the adhesiveness with the greatest effect by 3‐hydroxybenzoic acid (72 g·s). pH changes of the starch suspension caused by the addition of phenolic compounds and their structural diversity affected these functional properties of wheat starch to different extents. This study may provide a basis for the use of phytochemicals in functional and starch‐based staple foods.
Alternative Surgical Strategies and Favorable Outcomes in Patients with Medullary Thyroid Carcinoma in Japan: Experience of a Single Institution
Authors: Ito Yasuhiro , Miyauchi Akira , Yabuta Tomonori , Fukushima Mitsuhiro , Inoue Hiroyuki , Tomoda Chisato , Uruno Takashi , Kihara Minoru , Higashiyama Takuya , Takamura Yuuki , Miya Akihiro , Kobayashi Kaoru , Matsuzuka Fumio
Published: November 2008

Background

Medullary thyroid carcinoma (MTC) accounts only for 1.4% of all thyroid malignancies in Japan. Since 1996, we have performed hemithyroidectomy, instead of total thyroidectomy, for sporadic nonhereditary MTC when the primary lesion is located in only one lobe. Regarding lymph node dissection, modified radical neck dissection (MND) at least ipsilateral to the tumor has been routinely performed, even if there is no clinically apparent metastasis. We investigated the clinical outcomes of MTC patients in our department.

Methods

A series of 118 patients with MTC who underwent initial surgery between 1975 and 2005 were enrolled in this study. The RET gene mutations were analyzed for all patients and 46 had germline RET gene mutations. Of those 46 patients, 26 were diagnosed as MEN 2A and 2 were diagnosed as MEN 2B. Postoperative follow‐up periods averaged 141 months.

Results

Of 115 patients who did not have distant metastasis at surgery and who underwent locally curative surgery, 78 (67.8%) were biochemically cured. All patients without pathological lymph node metastasis were biochemically cured, and 44.8% of patients with node metastasis were also biochemically cured. The 10‐year and 20‐year disease‐free survival rates were 89.0% and 82.5%, respectively. None of the patients who did not show lymph node metastasis and only 2 (2.6%) of 78 patients who were biochemically cured showed clinically apparent carcinoma recurrence. The 10‐year and 20‐year cause‐specific survival rates were 96.6% and 91.7%, respectively. Lymph node metastasis, tumor size >4 cm, extrathyroid and extranodal tumor extensions significantly affected cause‐specific survival of patients.

Conclusions

Clinical outcomes of MTC patients in our series were better than those in Western countries, a result that might have resulted in part because of our routine MND regardless of whether clinically apparent node metastasis was detected.
Establishment of an SV40 large T antigen‐immortalized bovine brain cell line and its neuronal differentiation by dibutyryl‐cyclic AMP
Authors: Takenouchi Takato , Iwamaru Yoshifumi , Sato Mitsuru , Yokoyama Takashi , Kitani Hiroshi
Published: November 2008

Immortalized bovine brain cell lines provide ideal in vitro cellular infection models for bovine spongiform encephalopathies (BSEs) caused by prions without enduring species barrier. We have established an immortalized brain cell line (FBBC‐1 cells) from primary cultures of cryopreserved fetal bovine brain tissues after transfection with SV40 large T antigen. FBBC‐1 cells are stable after passaging to >100 population doublings after single cell cloning, with a generation time of 24 h. After the treatment with dibutyryl‐cyclic AMP, the cells ceased proliferation and extended neurite‐like processes that were immunostained with the antibody against tubulin βIII, a marker of immature neurons. Upregulation of tubulin βIII expression was confirmed by immunoblotting. These bovine cells expressed cellular prion protein and its processed smaller C1 fragment, and may provide an in vitro means of propagating cattle BSE prion.
Activating endogenous visceral pain modulation: A comparison of heterotopic stimulation methods in healthy controls
Authors: Wilder‐Smith Clive H. , Song Guanghui , Yeoh Khay Guan , Ho Khek Yu
Published: November 2008

All sensory input underlies modulation by endogenous central nervous system pathways. Dysfunctional endogenous pain modulation has been demonstrated in central sensitization and in several pain syndromes, including Irritable Bowel Syndrome (IBS) Activation of endogenous visceral pain modulation by heterotopic stimulation was compared using different methods. Rectal electrical or distension pain alone or with simultaneous (i.e. heterotopic) noxious hand or foot cold stimulation were investigated in randomized sequence in 14 male and 1 female healthy subjects.

Mean pain intensities on a visual analogue scale of 0–100 (95% CI) during tonic rectal electrical and distension stimulation alone were 64 (52–76) and 55 (39–71), respectively. Rectal distension pain decreased by 36% (18–55) with simultaneous hand and by 45% (24–66) with simultaneous foot cold pain. Rectal electrical pain decreased by 45% (29–61) during hand and by 46% (28–64) during foot cold pain. Facilitation, i.e. increased rectal pain during heterotopic stimulation was observed in only 1 of 60 stimulation runs.

Potent and consistent activation of endogenous visceral pain inhibition was achieved with heterotopic cold pain limb stimulation. Somato‐visceral convergence did not affect the effectiveness of induction of endogenous visceral pain inhibition in healthy subjects, as hand and foot heterotopic stimulation resulted in similar pain inhibition. Pain facilitation, as shown earlier in IBS patients, was not evident in healthy controls.
HDAC inhibition upregulates the expression of angiostatic ADAMTS1
Authors: Chou Chia-Wei , Chen Ching-Chow
Published: November 2008

HDAC inhibitors are promising anticancer agents that induce cell cycle arrest and apoptosis. However, the role of HDACs in cancer progression, such as angiogenesis and metastasis, remains largely unexplored. Among various HDAC inhibitors, we demonstrate that TSA and SAHA upregulated the expression of angiostatic ADAMTS1 in A549 cells. HDAC6 inhibitor tubacin, and knockdown of HDAC6, also lead to ADAMTS1 upregulation. By reporter, DAPA, and ChIP assays, the proximal GC boxes were demonstrated to be essential for ADAMTS1 induction. Decreased binding of SP1 and HDAC6 to the ADAMTS1 promoter after TSA treatment was also seen. These data suggest the involvement of HDAC6 and SP1 in the HDACi‐induced expression of angiostatic ADAMTS1.
Strong approximation of sets in BV(Ω)
Authors: de Gromard Thierry Quentin
Published: November 2008

Taking the argument used by De Giorgi to obtain the rectifiability of the reduced boundary of a set of finite perimeter in ℝN, we prove that a set E of finite perimeter in an open set Ω of ℝN may be approached, in the sense of the BV(Ω) norm, by sets whose boundary is included in a finite union of $\mathcal{C}^1$1 hypersurfaces; more precisely, arbitrarily large parts (for the $\mathcal{H}_{N-1}$N−1 measure in Ω) of the essential boundaries of E and of the approximating set coincide and are included in a single $\mathcal{C}^1$1 hypersurface.
Periodic motions in the Fermi—Ulam model
Authors: Jiang Mei-Yue
Published: November 2008

We consider the periodic solutions of the equation

satisfying −1 ≤ x ≤ 1 ẋ(t−) = −ẋ(t+) if x(t) = ±1, where f is a continuous function, periodic in t. A sequence of periodic solutions is obtained via the variational method.
Elevated iron stores are associated with HIV disease severity and mortality among postpartum women in Zimbabwe
Authors: Rawat R , Humphrey JH , Ntozini R , Mutasa K , Iliff PJ , Stoltzfus RJ
Published: November 2008

Objectives

The relationship between Fe status and HIV infection is complex and poorly understood. While anaemia is a major complication of HIV infection, higher Fe stores may be associated with disease progression. There is limited and conflicting data available from Africa.

Design

Cross-sectional and prospective cohort study.

Setting, subjects and methods

We examined the association between postpartum Fe status (Hb, serum ferritin (SF) and transferrin receptor (TfR)) and viral load (VL) and HIV-related mortality in 643 HIV-positive Zimbabwean women over a period of 12 months.

Results

In non-anaemic women a log10increase in SF was associated with a 2·3-fold increase in VL (P= 0·019); this association was absent in anaemic women. In prospective analyses, a log10increase in SF was associated with a 4-fold increase in mortality by 12 months (P= 0·002). Hb was negatively associated with VL (P= 0·001) and mortality (P= 0·047). The adverse associations between SF and both VL and mortality were found at SF concentrations >45 μg/l (P< 0·05). Controlling for α1acid glycoprotein, a marker of inflammation, attenuated the association between both SF and VL and mortality, but these remained significant.

Conclusions

These results are consistent with the hypothesis that high Fe stores have adverse consequences in HIV infection. If adverse consequences are real, our data suggest that they occur at SF concentrations exceeding those consistent with adequate Fe nutriture.
Body tides of a convecting, laterally heterogeneous, and aspherical Earth
Authors: Métivier Laurent , Conrad Clinton P.
Published: November 2008

Precise knowledge of Earth's body tides is crucial for correcting geodetic positioning measurements, satellite gravity surveys, and superconducting gravimeters with nanogal precision. With this aim, body tides are generally computed assuming a radially (or elliptically) stratified Earth. However, seismic tomography surveys and fluid dynamic studies show that thermal convection within Earth's mantle produces significant lateral heterogeneity exemplified by superplumes, superswells, and subducting slabs. To determine the influence of this heterogeneity on body tides, we used a tomographic model to constrain lateral variations in mantle density and rigidity. This heterogeneity drives convective flow that deflects Earth's surface and core‐mantle boundaries by a few kilometers; we used a viscous flow model to constrain this dynamically supported asphericity. After verifying this complete Earth model using geoid observations, we used the spectral element method to determine how Earth's body tides are perturbed compared to a spherical Earth. We find maximum radial perturbations of surface and geoid displacements of 0.3 and 0.1 mm, respectively, and tidal gravity variations of 150 nGal. The amplitude of tidal gravity perturbations depends strongly on location and is greatest above large mantle density anomalies: e.g., large dense slabs (South America, Indonesia, Marianas), hot spots (Hawaii, Iceland), and the East African Rift. Predicted gravity perturbations are 100 times larger than the present precision of superconducting gravimeters and are comparable in magnitude to the unexplained residue observed at some gravimeter stations after tidal corrections. While this residue has been attributed to unmodeled loading from ocean tides, body tide perturbations caused by convection‐induced mantle heterogeneity may contribute to this observed residue.
Connections between wintertime jet stream variability, oceanic surface heating, and transient eddy activity in the North Pacific
Authors: Ren Xuejuan , Zhang Yaocun , Xiang Yang
Published: November 2008

A set of statistical analyses of the fields from the European Center for Medium‐Range Weather Forecasts reanalysis (ERA‐40) are carried out to investigate the connections between three selected fields, namely, the wintertime western Pacific jet stream (WPJS), as represented by the zonal wind at 200 hPa; the oceanic surface heating represented by the latent and sensible heat fluxes; and the synoptic‐scale transient eddy activity (STEA) over the North Pacific. First, empirical orthogonal function (EOF) analysis is performed to characterize the wintertime WPJS variability. Further analyses yield the following conclusions. (1) The most dominant relationship among the three selected fields is strongly linked to the El Niño‐Southern Oscillation (ENSO). During ENSO events, anomalous zonal wind at 200 hPa downstream of the WPJS main body, shown in the first EOF, is accompanied by STEA anomalies around the region of the anomalous midlatitude zonal wind. (2) The strengthening (weakening) of the wintertime WPJS main body, shown in the second EOF, is connected to the surface heating anomalies in the Kuroshio and its extension region as well as to STEA anomalies in the region downstream of the WPJS main body. (3) The northward (southward) shift of the wintertime WPJS, represented in the third EOF, is closely related to the south‐north dipolar structure of the surface heating anomalies in the western North Pacific. The STEA spatial displacement is in conjunction with the shift of the jet stream in the same direction due to the dynamical connection between the winds and the eddies. Furthermore, the STEA anomalies in winter may cause the WPJS anomalies on the submonthly timescale. As a consequence, the northward (southward) shift of the STEA is harmoniously in favor of the similar jet shift.
Large‐scale dynamics of Saturn's magnetopause: Observations by Cassini
Authors: Achilleos N. , Arridge C. S. , Bertucci C. , Jackman C. M. , Dougherty M. K. , Khurana K. K. , Russell C. T.
Published: November 2008

The long‐term statistical behavior of the large‐scale structure of Saturn's magnetosphere has been investigated. Established statistical techniques for Jupiter have been applied to the kronian system, employing Cassini magnetometer data and a new empirical shape model of the magnetopause based on these data. The resulting distribution of standoff distance RMP for Saturn, covering a time interval of ∼400 days, is well‐described by a “dual” or “bimodal” model—the sum of two normal distributions with different means at ∼22 and ∼27 planetary radii. We have made a comparison between the dual model's prediction for the probability distribution of solar wind dynamic pressure at Saturn with a sequence of observations from the Cassini Plasma Spectrometer (CAPS) instrument. Although the solar wind dynamic pressure observations are limited to a smaller time interval than the magnetometer data, we find that their overall range is in broad agreement with the that of the modeled pressures. However, the bimodal structure exhibited by the model is not apparent in the solar wind data for the corresponding range of dynamic pressures (∼0.008 – 0.06 nPa), which suggests that other mechanisms at Saturn also influence the size distribution of the magnetopause. Considering internal processes at Saturn and their influence on magnetopause size, we conclude that the effect of internal mass loading and loss from the magnetospheric disk is plausibly able to explain the observed bimodal distribution in magnetopause standoff distance.
Explicitly simulated tropical convection over idealized warm pools
Authors: Liu Changhai , Moncrieff Mitchell W.
Published: November 2008

Two‐dimensional cloud‐system‐resolving simulations of convection over idealized warm pools are conducted to examine the relationship between the spatial patterns of tropical convection and the sea surface temperature (SST) distributions. Results show that the most active convection resides near the edge of warm pools, with a local minimum around the warmest center. This finding might provide an interpretation for the observations that peak convection is commonly located several degrees of latitude off the maximum SST over some tropical oceans. Factors potentially affecting the convective patterns are explored through sensitivity experiments. It is found that convection expands significantly and rainfall peaks are further displaced several hundred more kilometers away from the warmest water when the radiative cooling/heating is applied homogeneously across the domain. Conversely, when the wind‐induced surface flux variability is excluded, convective activity is confined within a much narrower area of high SSTs, but the overall spatial pattern is largely retained. Moreover, the surface friction exerts profound effects on the simulated convection and attendant large‐scale flow and is mostly responsible for the dual‐maximum precipitation and two‐cell circulation structure in the horizontal. These results suggest that as well as the temperature/pressure gradients resulting from the non‐uniform SSTs, other processes must be taken into consideration in the interpretation of observed tropical convection and circulation.
Metabolic and Hemodynamic Events after Changes in Neuronal Activity: Current Hypotheses, Theoretical Predictions and in vivo NMR Experimental Findings
Authors: Mangia Silvia , Giove Federico , Tkáč Ivan , Logothetis Nikos K , Henry Pierre-Gilles , Olman Cheryl A , Maraviglia Bruno , Di Salle Francesco , Uğurbil Kâmil
Published: November 2008

Unraveling the energy metabolism and the hemodynamic outcomes of excitatory and inhibitory neuronal activity is critical not only for our basic understanding of overall brain function, but also for the understanding of many brain disorders. Methodologies of magnetic resonance spectroscopy (MRS) and magnetic resonance imaging (MRI) are powerful tools for the noninvasive investigation of brain metabolism and physiology. However, the temporal and spatial resolution of in vivo MRS and MRI is not suitable to provide direct evidence for hypotheses that involve metabolic compartmentalization between different cell types, or to untangle the complex neuronal microcircuitry, which results in changes of electrical activity. This review aims at describing how the current models of brain metabolism, mainly built on the basis of in vitro evidence, relate to experimental findings recently obtained in vivo by 1H MRS, 13C MRS, and MRI. The hypotheses related to the role of different metabolic substrates, the metabolic neuron—glia interactions, along with the available theoretical predictions of the energy budget of neurotransmission will be discussed. In addition, the cellular and network mechanisms that characterize different types of increased and suppressed neuronal activity will be considered within the sensitivity-constraints of MRS and MRI.
Potential Usefulness ofD2RReporter Gene Imaging by IBF as Gene Therapy Monitoring for Cerebellar Neurodegenerative Diseases
Authors: Shiba Kazuhiro , Torashima Takashi , Hirai Hirokazu , Ogawa Kazuma , Akhter Nasima , Nakajima Kenichi , Kinuya Seigo , Mori Hirofumi
Published: November 2008

We investigated a gene expression imaging method to examine the level of therapeutic gene expression in the cerebellum. Using a human immunodeficiency virus derived lentivial vector, we expressed the dopamine D2receptor (D2R) as a reporter protein to mouse cerebellar Purkinje cells. Biodistribution and ex vivo autoradiography studies were performed by giving [125I]5-iodo-7- N-[(1-ethyl-2-pyrrolidinyl)methyl]carboxamide-2,3-dihydrobenzofuran ([125I]IBF) (1.85MBq), as a radioactive D2R ligand, to model mice expressing the D2R with an HA tag (HA-D2R) in the cerebellum. In this study, [125I]IBF was bound to the D2R expressed in the cerebellum of the model mice selectively. Immunostaining was performed to confirm the HA-D2R expression in the cerebellum of the model mice. A significant correlation ( r = 0.900, P< 0.001) between areas that expressed HA-D2R by immunostaining and areas in which [125I]IBF accumulated by the ex vivo autoradiograms was found. These results indicated that radioiodinated IBF is useful as a reporter probe to detect D2R reporter gene expression, which can be used for monitoring therapeutic gene expression in the cerebellum.
Age-Dependent Effects of Testosterone in Experimental Stroke
Authors: Cheng Jian , Hu Weidong , Toung Thomas J , Zhang Zhizheng , Parker Susan M , Roselli Charles E , Hurn Patricia D
Published: November 2008

Although male sex is a well-recognized risk factor for stroke, the role of androgens in cerebral ischemia remains unclear. Therefore, we evaluated effects of testosterone on infarct size in both young adult and middle-aged rats (Wistar, 3-month versus 14-month old) and mice (C57/BL6, 3-month versus 12-month old) subjected to middle cerebral artery occlusion. In young adult groups, castrates displayed less ischemic damage as compared with intact males and castrates with testosterone replacement (Cortex: 24% in castrates versus 42% in intact versus 40% with testosterone; Striatum: 45% versus 73% versus 70%) at 22 h reperfusion. Surprisingly, supplementing testosterone in middle-aged rats to the physiologic levels ordinarily seen in young males reduced infarction (Cortex: 2% with testosterone versus 31%; Striatum: 38% with testosterone versus 68%). Testosterone effects on infarct size were blocked by the androgen receptor (AR) antagonist flutamide and further confirmed in young versus middle-aged mice. Baseline cerebral aromatase mRNA levels and activity were not different between young and middle-aged rats. Aromatase activity increased in ischemic tissue, but only in young males. Lastly, stroke damage was not different in aging aromatase knockout mice versus wild-type controls. Our findings indicate that testosterone's effects in experimental stroke are age dependent, mediated via AR, but not cerebral aromatase.
Dab2 regulates clathrin assembly and cell spreading
Authors: Chetrit David , Ziv Naomi , Ehrlich Marcelo
Published: November 2008

The recruitment of clathrin to the membrane and its assembly into coated pits results from its interaction with endocytic adaptors and other regulatory proteins in the context of a specific lipid microenvironment. Dab2 (disabled 2) is a mitotic phosphoprotein and a monomeric adaptor for clathrin-mediated endocytosis. In the present study, we employed GFP (green fluorescent protein) fusion constructs of different isoforms and mutants of rat Dab2 and characterized their effect on the size, distribution and dynamics of clathrin assemblies. Enhanced levels of expression of the p82 isoform of Dab2 in COS7 cells induced enlarged clathrin assemblies at the plasma membrane. p82–clathrin assemblies, which concentrate additional endocytic proteins, such as AP2 (adaptor protein 2) and epsin, are dynamic structures in which both p82 and clathrin exchange actively between the membrane-bound and cytosolic sub-populations. The ability of p82 to induce enlarged clathrin assemblies is dependent on the presence of a functional PTB domain (phosphotyrosine-binding domain), on binding to clathrin and phospholipids, and on a newly identified and evolutionarily conserved poly-lysine stretch which precedes the PTB domain. These same molecular features are required for Dab2 to enhance the spreading of COS7 cells on fibronectin. The ability of the p82 isoform of Dab2 to enhance cell spreading was confirmed in both HeLa cells and HBL cells (human breast epithelial cells). COS7 cells expressing GFP–p82 and plated on to fibronectin concentrate the β1 integrin into clathrin–p82 assemblies. Furthermore, during cell spreading, p82–clathrin assemblies concentrate at the site of the initial cell–matrix contact and are absent from regions of intense membrane ruffling. We propose a role for Dab2 and clathrin in integrin-mediated cell spreading.