bluuebunny/crossref_metadata_2025 huggingface dataset:
Geographical differences in the proportion of human group A rotavirus strains within New Zealand during one epidemic season
Authors: Chandrahasen Clarissa , Grimwood Keith , Redshaw Natalie , Rich Fenella J. , Wood Catherine , Stanley James , Kirman Joanna R. ,   on behalf of the New Zealand Rotavirus Study Group
Published: March 2010

The prospect of future rotavirus vaccine programs means it is important to understand rotavirus strain diversity within New Zealand, especially if this was to influence vaccine effectiveness. The G‐genotype of 359 group A rotavirus strains isolated from 416 stool samples collected from June 2005 to May 2006 (inclusive) from children less than 5 years of age in multiple centers throughout New Zealand was determined. G1 was the dominant circulating strain (55.8%) followed by G4 (21.4%), G3 (3.4%), G9 (3.4%) G2 (1.0%), and mixed infection (1.0%). Two less common strains, G6 and G8, were identified for the first time in New Zealand. P genotypes were determined for a random 10% of samples containing the common G‐type strains, and all samples with an unusual G‐type. All samples able to be tested contained P[8] bearing strains, except for G1P[4], G2P[4], and G8P[14] strains. Importantly, significant differences in strain frequency were found between samples collected from the North and South Islands of New Zealand. G1 was the most commonly identified strain in the North Island (81.9%); whereas G4 predominated in the South Island (39.6%). Of note, no significant differences in the relative frequency of rotavirus strains were observed between samples collected from children treated in hospital compared to samples collected from children seen by their primary healthcare provider in the community. Regional strain variation highlights the importance of ensuring multi‐center surveillance to help monitor program effectiveness when rotavirus vaccines are introduced into New Zealand's national childhood immunization schedule. J. Med. Virol. 82: 897–902, 2010. © 2010 Wiley‐Liss, Inc.
Omega‐3 fatty acids reverse age‐related decreases in nuclear receptors and increase neurogenesis in old rats
Authors: Dyall Simon C. , Michael Gregory J. , Michael‐Titus Adina T.
Published: March 2010

Retinoic acid receptors (RARs), retinoid X receptors (RXRs), and peroxisome proliferator‐activated receptors (PPARs) are transcription factors involved in many cellular processes, such as learning and memory. RAR and RXR mRNA levels decrease with ageing, and the decreases can be reversed by retinoic acid treatment, which also alleviates age‐related memory deficits. The omega‐3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have neuroprotective effects in the aged brain and are endogenous ligands of RXR and PPAR. We investigated whether dietary EPA and DHA supplementation reverses age‐related declines in protein levels of these receptors in rat forebrain. Two studies were conducted comparing adult and old rats. In the first, old rats were fed standard or EPA/DHA‐enriched (270 mg/kg/day, EPA to DHA ratio 1.5:1) diets for 12 weeks. Analysis by Western blot revealed significant decreases in RARα, RXRα, RXRβ, and PPARγ in the forebrain with ageing, which were reversed by supplementation. Immunohistochemical analysis of the hippocampus showed significant age‐related decreases in RARα and RXRβ expression in CA1 and the dentate gyrus, which were restored by supplementation. Decreases in hippocampal doublecortin expression were also partially alleviated, suggesting a positive effect on neurogenesis. We also investigated the effects of DHA supplementation (300 mg/kg/day for 12 weeks) on RARα, RXRα, and RXRβ expression in the prefrontal cortex, striatum, and hippocampus. Overall, DHA supplementation appeared to increase receptor expression compared with the untreated old group. These observations illustrate additional mechanisms that might underlie the neuroprotective effects of omega‐3 fatty acids in ageing. © 2010 Wiley‐Liss, Inc.
Diverse roles of extracellular calcium‐sensing receptor in the central nervous system
Authors: Bandyopadhyay Sanghamitra , Tfelt‐Hansen Jacob , Chattopadhyay Naibedya
Published: March 2010

The G‐protein‐coupled calcium‐sensing receptor (CaSR), upon activation by Ca2+ or other physiologically relevant polycationic molecules, performs diverse functions in the brain. The CaSR is widely expressed in the central nervous system (CNS) and is characterized by a robust increase in its expression during postnatal brain development over adult levels throughout the CNS. Developmental increases in CaSR levels in brain correlate with myelinogenesis. Indeed, neural stem cells differentiating to the oligodendrocyte lineage exhibit the highest CaSR expression compared with those differentiating to astrocytic or neuronal lineages. In adult CNS, CaSR has broad relevance in maintaining local ionic homeostasis. CaSR shares an evolutionary relationship with the metabotropic glutamate receptor and forms heteromeric complexes with the type B‐aminobutyric acid receptor subunits that affects its cell surface expression, activation, signaling, and functions. In normal physiology as well as in pathologic conditions, CaSR is activated by signals arising from mineral ions, amino acids, polyamines, glutathione, and amyloid‐β in conjunction with Ca2+ and other divalent cationic ligands. CaSR activation regulates membrane excitability of neurons and glia and affects myelination, olfactory and gustatory signal integration, axonal and dendritic growth, and gonadotrophin‐releasing hormonal‐neuronal migration. Insofar as the CaSR is a clinically important therapeutic target for parathyroid disorders, development of its agonists or antagonists as therapeutics for CNS disorder could be a major breakthrough. © 2010 Wiley‐Liss, Inc.
A wavelet approach to the short‐term to pluri‐decennal variability of streamflow in the Mississippi river basin from 1934 to 1998
Authors: Massei N. , Laignel B. , Rosero E. , Motelay‐massei A. , Deloffre J. , Yang Z.‐L. , Rossi A.
Published: March 2010

The temporal variability of streamflow in the Mississippi river basin, including its major tributaries (Missouri, Upper Mississippi, Ohio and Arkansas rivers), was analysed using continuous wavelet methods in order to detect possible changes over the past 60 years. Long‐ to short‐term fluctuations were investigated. The results were compared with SOI, PDO and NAO indices and precipitation time series and were also processed by wavelet methods. A major change point around 1970, also reported in other works, was recovered in all climate and hydrological processes. It is characterised by the occurrence of an 8–16‐year mode for Upper Mississippi and Missouri and of a 3–6‐year mode for all rivers. Two other discontinuities around the mid‐1950s and 1985 were also detected. A strong power attenuation of the annual cycle in the Arkansas, Upper Mississippi and Missouri rivers was also found between 1955 and 1975. In general, the dominant modes of inter‐annual to pluri‐annual streamflow variability lay in the 2–4‐year, 4–8‐year and 10–16‐year ranges, which was typical of SOI for the period of study. A preferential link with the Mississippi basin headwater zone (i.e. Upper Mississippi and Missouri) was deduced during the ≈ 1934–1950 and ≈ 1970–1985 periods.

Overall, the contribution of inter‐annual to pluri‐annual oscillations ranged from 6.6 to 26% of streamflow variance, while the short‐term scales (<2–3 weeks) explained from 1.1 to 6.4%. The annual cyclicity explained from 19.1 to 48.6% of streamflow variance. High‐frequency streamflow fluctuations linked to synoptic activity were also found to increase after 1955 for all basins except Upper and Lower Mississippi, apparently modulated by a ≈ 2–4‐yr oscillation. Copyright © 2010 Royal Meteorological Society
Screening and assessment of crime victimization and its effects
Authors: Hanson Rochelle F. , Self‐Brown Shannon
Published: March 2010

The authors provide a review of tools used to screen and assess history and mental health consequences of adult crime victimization. These measures can be utilized across a broad range of settings that may serve crime victims, including venues for first response (e.g., law enforcement offices or emergency departments), primary medical care, or mental health treatment facilities, regardless of whether or not the crime was reported. The authors conclude with a discussion on limitations in the field and directions for future research.
Preparation of Biodegradable Liquid Core PLLA Microcapsules and Hollow PLLA Microcapsules Using Microfluidics
Authors: Lensen Dennis , van Breukelen Kevin , Vriezema Dennis M. , van Hest Jan C. M.
Published: March 2010

Biodegradable PLLA capsules with a narrow size distribution were prepared using a microfluidics platform. With this technique, an oil‐in‐water emulsion was produced in which the polymer, a hydrophobic non‐volatile non‐solvent and a hydrophobic model drug were dissolved in the organic phase. The polymer precipitated at the droplet interface, yielding a drug deliverable microcapsule of which the release of this model drug was investigated. These capsules with an organic phase in the core were also used to prepare hollow particles by conveniently removing the core phase by lyophilization. Optimal conditions for the preparation of biodegradable capsules were found with respect to the flow rate of the continuous phase and the molecular weight of the PLLA polymer. This approach of preparing biodegradable capsules is of potential interest for the field of drug delivery.

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Ring‐Opening Polymerization of Propylene Oxide Catalyzed by a Calcium‐Chloride‐Modified Zinc‐Cobalt Double Metal‐Cyanide Complex
Authors: Huang Yi‐Jun , Zhang Xing‐Hong , Hua Zheng‐Jiang , Chen Shi‐Liang , Qi Guo‐Rong
Published: March 2010

Highly active CaCl2‐modified Zn‐Co(III) DMCs were prepared. XRD results showed that the modified catalyst Ca‐DMC containing 0.14 wt.‐% CaCl2 was amorphous. A higher polymer yield (>61 kg polymer/g catalyst) and a shorter induction period for ROP of PO were observed for Ca‐DMC than for unmodified DMC catalysts. An initiator had an inhibitory effect on the initiation and polymerization rate of PO ROP. As the molar ratio of the initiator functionality to the catalyst was increased, the reaction rate and polymer yield decreased, whereas the induction period increased. An increase in reaction temperature tended to reduce the polymer yield and broaden the MWD. The 13C NMR spectrum for an oligomer from a model polymerization without an initiator revealed that the main terminal unit of the polymer was CH2CH(CH3)OH because H2O in the system participated in reaction initiation. Cl− and t‐BuOH may also initiate the reaction according to the small amounts of terminal CH2Cl and OC(CH3)3 units observed by 13C NMR spectroscopy. On the basis of common characteristics and some new evidence for DMC catalysis, a mechanism similar to a classical coordination insertion process is proposed.

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RAFT Polymerization Meets Coordination Chemistry: Synthesis of a Polymer‐Based Iridium(III) Emitter
Authors: Ulbricht Christoph , Becer Caglar Remzi , Winter Andreas , Schubert Ulrich S.
Published: March 2010

A synthetic approach toward the synthesis of well‐defined copolymers with attached phosphorescent iridium(III) emitters is presented. A reactive µ‐hydroxy‐bridged precursor complex has been utilized to coordinate suitable ligand sites of a methacrylate‐based copolymer. The starting copolymer has been synthesized via the reversible addition fragmentation chain transfer (RAFT) polymerization technique. Using a reactive complex species, the coordination reaction at the copolymer could be performed under very mild conditions in the absence of any supporting additives.

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Preparation of Stable Miniemulsions of Poly(2‐ethyl hexyl acrylate‐co‐vinyl acetate)
Authors: Fonseca Gabriela E. , McKenna Timothy F.L. , Dubé Marc A.
Published: March 2010

Summary: This paper presents the results of the preparation of miniemulsions as well as the subsequent copolymerizations of 2‐ethyl hexyl acrylate and vinyl acetate. The miniemulsions were prepared using a mixture of an anionic and a non‐ionic surfactant. Sodium dodecyl sulfate (SDS) was used as the anionic surfactant and two non‐ionic surfactants were studied: Triton X‐405 and Disponil A3065. The miniemulsions prepared with a 90/10 mol.‐% Disponil A3065 were able to reach a kinetically‐stable state to yield latexes with 43 wt.‐% solids content with a maximum change in the number of particles (Np) with respect to the number of droplets (Nd) of ∼6%. A 23 factorial design was then used to discern the influence of monomer, chain transfer agent and surfactant concentration on the droplet size distribution (DSD) and particle size distribution (PSD). Pressure‐sensitive adhesive (PSA) properties were also examined.
Ionic Conductivity in Solutions of Poly(ethylene oxide) and Lithium Perchlorate
Authors: Nasir Noor Hidaya Abdul , Chan Chin Han , Kammer Hans‐Werner , Sim Lai Har , Yahya Muhd Zu Azahan
Published: March 2010

Summary: Solution casting technique served to prepare solid solutions of lithium perchlorate and poly(ethylene oxide) (PEO) having different molecular masses. Salt concentrations of solutions were varied between around 2 and 13 wt%. Crystallinity and melting point depression served to determine composition and content of amorphous phase as well as thermodynamic behavior of the solutions. Conductivity as a function of salt concentration in the amorphous phase follows a power law at constant temperature (30 °C). It results that both exponent and mobility of charge carriers increase with ascending molecular mass of PEO. The mobility follows an increase with molecular mass proportional to M2.8 indicating dependence of mobility on interstitial volume between chain molecules. Deviation of solution from perfect behavior can be evaluated by melting point depression. Accordingly, increase in conductivity is preferably related to approach to perfect solution behavior. Determination of dielectric function allows some conclusion about ion pair formation in the systems under discussion. It turns out that probability of ion pair formation decreases with increasing molecular mass of PEO in agreement with thermodynamic behavior of the solutions.
Isothermal and Non‐Isothermal Crystallization Kinetics and Morphology of Poly(trimethylene terephthalate)/Multiwalled Carbon Nanotube Composites
Authors: Gupta Anju , Choudhary Veena
Published: March 2010

Summary: Multiwalled carbon nanotubes (MWCNTs) synthesized using chemical vapor deposition method were dispersed in poly(trimethylene terephthalate) (PTT, Mv = 88,000) by melt compounding technique using DMS microcompounder. The nanocomposites consisting of varying amounts of MWCNTs were characterized by differential scanning calorimetry (DSC), wide‐angle X‐ray diffraction (WAXD), Raman spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The effect of carbon nanotubes on the crystallization behavior (under isothermal and non isothermal crystallization conditions) of PTT was studied using DSC. The presence of carbon nanotubes didn't show any significant effect on crystallization temperature of PTT matrix under non‐isothermal conditions. Crystallization studies under isothermal conditions were carried out at different temperatures i.e 185, 190, 195 and 200 °C. Complete crystallization was observed within 60 sec at 185 °C whereas at 200 °C, longer time was required for complete crystallization. Crystal growth was also investigated using hot stage polarizing microscope (PLM). The effect of annealing time at 200 °C was investigated in the presence as well as in the absence of varying amounts of MWCNTs. Spherulitic growth was seen and the spherulite size in all the samples increased with annealing time. Morphological characterization using SEM and TEM showed a uniform dispersion of MWCNTs and poor compatibility with PTT matrix.
Rheological Study Bringing New Insights into PET/PC Reactive Blends
Authors: Pereira Patrícia S.C. , Mendes Luis C. , Ramos Valéria D.
Published: March 2010

Summary: Extruded poly(ethylene terephthalate)/polycarbonate (PET/PC) blends, with/without cobalt catalyst and at different polymer ratios, were prepared. Rheological behaviour was discussed in terms of storage (G′) and loss (G″) moduli, loss tangent (Tan δ) and viscosity (η). Both G′ and G″ increased as a function of frequency for all blends. PET was the matrix in the blends with 80 and 50 wt% of polyester but in the PC rich‐blend an inversion was observed. In all cases, lower Tan δ values were achieved at high frequencies. The viscosity behaviour showed a catalyst dependency. PET dictated the rheological properties of the blends without catalyst whereas PC governed blends with catalyst. Alcoholysis and acidolysis reactions plus a transesterification reaction occurred on the interface was dependent on the matrix component. These reactions seem to occur at higher extent in blends in which PET is the matrix but the inverse happened in the PC rich‐blend.
Structure and Properties of Multilayered PET/PC Composites
Authors: Adhikari Rameshwar , Seydewitz Volker , Löschner Katrin , Michler Goerg H. , Hiltner Anne , Baer Eric
Published: March 2010

Summary: With the aid of layer multiplying coextrusion techniques, polymer composites comprising up to thousand of uniform and alternating layers polyethylene terephthalate (PET) and polycarbonate (PC) were produced. Morphology and micromechanical deformation processes in these composites were investigated by means of transmission electron microscopy (TEM) and atomic force microscopy (AFM). In particular, the effect of thickness of individual layers on the large strain deformation micromechanisms was analyzed. On decreasing the thickness of individual polymer layers, a transition in deformation mechanism from two‐component behaviour (i.e. the localization of shear bands in individual layer) to one‐component‐like behaviour (with the shear bands passing unhindered through different layers) was observed at the layer thickness of ca. 1 µm. On further decreasing the layer thickness below 100 nm, the composites exhibited homogeneous plastic deformation (i.e. no localization of deformation). In contrast to pure PET, even after long annealing, the composites showed tough behaviour during tensile loading.
Dielectric Relaxation Phenomena and Electric Properties of Conductive Composite Polyurethane/Polyaniline Films
Authors: Bouanga C. Vanga , Fatyeyeva K. , Baillif P.‐Y. , Khaokong C. , Pilard J.‐F. , Tabellout M.
Published: March 2010

Summary: Composite polyurethane/polyaniline (PU/PANI) films have been chemically prepared by oxidative in‐situ polymerization of aniline inside the previously swelled PU film. Swelling kinetic studies have shown that for PU films the swelling degree of aniline is 25 wt.%. The dielectric and electrical properties of the composite films were measured using dielectric relaxation spectroscopy and four‐probe method. Dielectric measurements as a function of temperature and frequency revealed the presence of a relaxation process for the composite PU/PANI‐HCl film. This relaxation was explained in terms of interfacial polarization due to the double‐layered structure of the composite film. The activation energy values found by dielectric and electrical measurements are close and this result confirms the conducting character of the PANI containing layer.
Corrosion behaviour of stainless steels after low temperature thermochemical treatment
Authors: Spies H.‐J. , Eckstein Ch. , Biermann H. , Franke A.
Published: March 2010

The corrosion behaviour of nitrided, carburised and nitrocarburised samples of the steels X2CrNiMo17‐12‐2 (AISI 316L) and X2CrNiMoN22‐5‐3 (UNS 31803) was tested with electrochemical methods. Generally the current density potential curves of the samples are highly sensitive on the chromium depletion of the matrix due to the precipitation of chromium nitrides at the grain boundaries. It was observed that in this case, especially in 0.05M sulphuric acid, the passive current density in the complete range of the current density potential curve increases considerably. A criterion derived for the beginning of the decomposition of the expanded austenite allows the determination of its stability in dependence on the treatment temperature and time. The expanded carbon austenite has a higher thermal stability compared to the expanded nitrogen austenite. By controlled sequential removal of the samples surfaces the corrosion behaviour into the depth of the surface layers was investigated.

Das Korrosionsverhalten nitrierter, carburierter und nitrocarburierter Proben der Stähle X2CrNiMo17‐12‐2 (AISI 316L) und X2CrNiMoN22‐5‐3 (UNS 31803) wurde mit elektrochemischen Methoden untersucht. Die Stromdichte‐Potenzial‐Kurven reagierten sehr empfindlich auf eine Chromverarmung der Matrix durch die Ausscheidung von Chromnitriden an Korngrenzen. Es wurde beobachtet, dass sich besonders bei den in 0,05M Schwefelsäure aufgenommenen Stromdichte‐Potenzial‐Kurven die Passivstromdichte im gesamten Bereich deutlich erhöhte. Ein daraus abgeleitetes Kriterium für den beginnenden Zerfall des expandierten Austenites ermöglicht eine Beschreibung seiner Stabilität in Abhängigkeit von den Behandlungsbedingungen. Der expandierte Kohlenstoffaustenit besitzt eine höhere thermische Stabilität als der expandierte Stickstoffaustenit. Durch kontrollierte Schichtabträge wurde das Korrosionsverhalten der Randschicht mit wachsendem Oberflächenabstand untersucht.
Sythhesis of coral‐like and spherical nanoparticles of barium titanate using factorial and Taguchi experimental design
Authors: Edrissi M. , Hosseinabadi H. Arabian
Published: March 2010

High purity barium titanate (BaTiO3) nanoparticle and its coral like architectures were synthesized in a laboratory scale from BaO and TiCl4 by microwave hydrothermal processing using a mixture of 0.1:2 volume ratio of Triethanalamine and distilled deionized water. The products were characterized by XRD, LLS, SEM and wet chemical analysis. The size of barium titanate particles was in the range of 5–25 nm with average particle size of 15.5 nm. The two dimensional coral – like product had the diameter of (3–18 nm and length of 140–420 nm). The experiments were designed to fulfill the 23 factorial and L4 Taguchi designs. Data analysis was performed using MINITAB software.
KRAS mutant lung cancer cells are differentially responsive to MEK inhibitor due to AKT or STAT3 activation: Implication for combinatorial approach
Authors: Yoon Young‐Kwang , Kim Hwang‐Phill , Han Sae‐Won , Oh Do Youn , Im Seock‐Ah , Bang Yung‐Jue , Kim Tae‐You
Published: March 2010

KRAS is frequently mutated in nonsmall cell lung cancer (NSCLC), resulting in the activation of the MAPK/ERK kinase (MEK)/ERK pathway. High‐throughput mutation profile has shown that lung cancer frequently harbors comutation of cancer‐related genes. Therefore, given that cancer cells have multiple genetic alterations, combinatorial therapeutic strategy is demanded for effective cancer therapy. To address this, we first characterized MEK dependence in four NSCLC cells. Two cells (H358, A549) carried KRAS mutation only, and the other two (H23, H157) harbored comutation of KRAS/PTEN. H358 cells with KRAS mutation only were sensitive to MEK inhibition. However, the other KRAS mutant A549 cells were resistant to MEK inhibition. Previously, we have shown that dual inhibition of EGFR and MEK signaling shows a synergistic effect on KRAS mutant gastric cancer cells by suppressing compensatory activation of AKT. Here we also observed that this combination was effective in KRAS mutant A549 cells. However, the combination was ineffective in H23 and 157 cells with comutation of KRAS/PTEN. Compared to KRAS mutant/PTEN wild‐type cells, signal transducer and activator of transcription 3 (STAT3) was significantly activated following MEK inhibition in KRAS/PTEN comutant cells. Combined STAT3 inhibition by a JAK2 inhibitor or gene knockdown with MEK inhibition blocked STAT3 activation, synergistically suppressed cell growth, and induced apoptosis in comutant cells. Taken together, our study provides molecular insights that help explain the heterogeneous response to MEK inhibition in KRAS mutant lung cancers, and presents a rationale for the clinical investigation of combination of MEK and EGFR inhibitor or MEK and JAK2 inhibitor depending on PTEN status. © 2010 Wiley‐Liss, Inc.
Stimulators of AMP‐activated kinase (AMPK) inhibit seawater‐ but not cAMP‐induced oocyte maturation in a marine worm: Implications for interactions between cAMP and AMPK signaling
Authors: Stricker Stephen A. , Swiderek Lee , Nguyen Thanh
Published: March 2010

Previous studies have shown that elevations in intraoocytic cAMP prevent mammalian oocytes from maturing, whereas cAMP degradation allows these oocytes to begin maturation, as evidenced by the onset of oocyte nuclear disassembly (=“germinal vesicle breakdown”, GVBD). Moreover, such cAMP degradation not only reduces cAMP levels but also generates AMP, which in turn can stimulate AMP‐activated kinase (AMPK), a well‐documented inducer of GVBD in mice. Alternatively, in some marine invertebrates, intraoocytic cAMP triggers, rather than blocks, GVBD, and whether AMPK up‐ or downregulates maturation in these species has not been tested. Thus, AMPK was monitored in the nemertean worm Cerebratulus during GVBD stimulated by seawater (SW) or cAMP elevators. In oocytes lacking surrounding follicle cells, AMPK activity was initially elevated in immature oocytes but subsequently reduced during SW‐ or cAMP‐induced GVBD, given that the catalytic α‐subunit of AMPK in maturing oocytes displayed a decreased stimulatory phosphorylation at T172 and an increased inhibitory phosphorylation at S485/491. Accordingly, AMPK‐mediated phosphorylation of acetyl‐CoA carboxylase, a known target of active AMPK, also declined during maturation. Moreover, treatments with either ice‐cold calcium‐free seawater (CaFSW) or AMPK agonists dissolved in SW maintained AMPK activity and inhibited GVBD. Conversely, adding cAMP elevators to CaFSW‐ or SW‐solutions of AMPK activators restored GVBD while promoting S485/491 phosphorylation and AMPK deactivation. Collectively, such findings not only demonstrate for the first time that intraoocytic AMPK can block GVBD in the absence of surrounding follicle cells, but these results also provide evidence for a novel GVBD‐regulating mechanism involving AMPK deactivation by cAMP‐mediated S485/491 phosphorylation. Mol. Reprod. Dev. 77: 497–510, 2010. © 2010 Wiley‐Liss, Inc.
A note on the online nature of the railway delay management problem
Authors: Kliewer Natalia , Suhl Leena
Published: March 2010

Unavoidable disruptions induce the necessity of delay management in timetable‐driven passenger rail traffic. Minimizing the negative consequences of delays becomes one of the most relevant challenges for the economic success, as it directly affects the timeliness of passengers, which is a core indicator of customer satisfaction. In this article, we evaluate and compare various delay management strategies in a passenger railway network. A simulator has been implemented to generate delays and perform operations control decisions to resolve connection conflicts induced through passenger connections involving delayed trains. We compare dispatching strategies based on mathematical optimization with simple rule‐based strategies. Simulation runs with a timetable from the long‐distance passenger traffic of German Railways show that, due to the online nature of this decision problem, a simple waiting time rule strategy can outperform a strategy where the operations are reoptimized online after each disruption. © 2010 Wiley Periodicals, Inc. NETWORKS, 2011
Experimental study of speed up techniques for timetable information systems
Authors: Bauer Reinhard , Delling Daniel , Wagner Dorothea
Published: March 2010

In recent years, many speed up techniques for DIJKSTRA Algorithm have been developed. Unfortunately, research mainly focused on road networks although fast algorithms are also needed for other applications like timetable information systems. Even worse, the adaption of recently developed techniques to graphs deriving from timetable information problems is often more complicated than expected. In this work, we check whether results from road networks are transferable to timetable information systems. To this end, we present an extensive experimental study of the most prominent speed up techniques on inputs deriving from different applications. It turns out that recently developed techniques are much slower on graphs derived from timetable information problems than on road networks. In addition, we gain interesting insights into the behavior of speed up techniques in general. © 2010 Wiley Periodicals, Inc. NETWORKS, 2011
An advanced boundary element method for solving 2D and 3D static problems in Mindlin's strain‐gradient theory of elasticity
Authors: Karlis G. F. , Charalambopoulos A. , Polyzos D.
Published: March 2010

An advanced boundary element method (BEM) for solving two‐ (2D) and three‐dimensional (3D) problems in materials with microstructural effects is presented. The analysis is performed in the context of Mindlin's Form‐II gradient elastic theory. The fundamental solution of the equilibrium partial differential equation is explicitly derived. The integral representation of the problem, consisting of two boundary integral equations, one for displacements and the other for its normal derivative, is developed. The global boundary of the analyzed domain is discretized into quadratic line and quadrilateral elements for 2D and 3D problems, respectively. Representative 2D and 3D numerical examples are presented to illustrate the method, demonstrate its accuracy and efficiency and assess the gradient effect on the response. The importance of satisfying the correct boundary conditions in gradient elastic problems is illustrated with the solution of simple 2D problems. Copyright © 2010 John Wiley & Sons, Ltd.
Differential proteomic analysis using iTRAQ reveals changes in thylakoids associated with Photosystem II‐acquired thermotolerance in Synechocystis sp. PCC 6803
Authors: Rowland John G. , Simon William J. , Nishiyama Yoshitaka , Slabas Antoni R.
Published: March 2010

Growth temperature has a marked influence on the thermotolerance of photosystem II (PSII), which is the most heat‐sensitive component of photosynthesis. Using Synechocystis sp. PCC 6803 we have established that thylakoids isolated from cells grown at 38°C have a greater degree of thermotolerance than those isolated from cells grown at 25°C. Reconstitution experiments using Triton X‐100 protein extracts of these thylakoids added to Triton‐treated thylakoid membranes further indicated that the 38°C Triton extract contains proteins that are directly capable of enhancing PSII thermotolerance. We have used 4‐plex iTRAQ, extensive off‐line fractionation and sample re‐injection to comprehensively identify the differences between these two preparations that may be responsible for the observed effects on PSII thermotolerance. This has resulted in the reproducible identification of 168 proteins out of a total of 385 distinct proteins. Our results have identified 15 proteins whose levels are increased in extracts that result in increased thermotolerance of PSII and 33 proteins whose levels decrease. Notably, components of the cytochrome b6/f and NADH dehydrogenase complexes, crucial components in electron transport, are approximately twofold more abundant in 38°C thylakoid extracts. The possible biological importance of these changes is discussed.
Polymethine cyanine dyes in β‐cyclodextrin solution: multiple equilibria and chemical oxidation
Authors: Barros Teresa C. , Toma Sergio H. , Toma Henrique E. , Bastos Erick L. , Baptista Mauricio S.
Published: March 2010

Absorption and fluorescence spectroscopy, electrochemical techniques, and semiempirical calculations were employed to characterize the multiple complexation equilibria between two polymethine cyanine dyes (IR‐786 and Indocyanine green‐ICG, S) and β‐cyclodextrin (β‐CD, L), as well as the chemical reactivity of the complexed and uncomplexed species against the oxidizing agents hypochlorite (HC) and hydrogen peroxide (HP). IR‐786 dimerization is favored with the increase in β‐CD concentration in the form of (SL)2 complexes. In the case of ICG, free dimers (D) and SL complexes are favored. Both IR‐786 and ICG react and discolor in the presence of HC and HP. For IR‐786, the reaction with HP and HC proceeds with observed rate constants of 10−3 and 0.28 s−1 and second‐order rate constants (k2) of ∼10−3 and 104 M−1s−1, respectively. The intermediate species observed in the bleaching reactions of IR‐786 and ICG were shown, by cyclic voltammetry and VIS absorption, to result from one electron oxidation. IR‐786 complexed with β‐CD is protected against bleaching in the presence of HP and HC by factors of 20 and 4, respectively. This protection was not observed in ICG complexes. Superdelocalizability profile of both dyes and frontier orbital analysis indicates that β‐CD does not protect ICG from oxidation by HP or HC, whereas the 2:2 IR‐786/β‐Cd complex is able to avoid the oxidation of IR‐786. We concluded that the decrease in the chemical reactivity of the dyes against oxidant agents in the presence of β‐CD is due to the formation of (SL)2 complexes. Copyright © 2010 John Wiley & Sons, Ltd.
Factors correlated with fatigue in breast cancer survivors undergoing a rehabilitation course, Denmark, 2002–2005
Authors: Schultz Simon Lawaetz , Dalton Susanne Oksbjerg , Christensen Jane , Carlsen Kathrine , Ross Lone , Johansen Christoffer
Published: March 2010

Objective: The aim of this prospective cohort study was to identify factors associated with fatigue in women with breast cancer who attended a 6‐day rehabilitation course. Furthermore, to investigate level of fatigue 1 year after the rehabilitation course, after accounting for baseline fatigue levels.

 Methods: Between 2002 and 2005 we included 775 women with breast cancer and measured fatigue, emotional functioning and insomnia using the EORTC subscales and sociodemographics from a baseline questionnaire prior to participation in the rehabilitation course. Information on disease‐specific and treatment factors was obtained from a nationwide clinical database. From the 12‐month follow‐up questionnaire we obtained level of fatigue. We estimated the influence of factors on the relative risk for a 10‐points increase in fatigue score in generalised linear models. For the analysis of fatigue at 12 months follow‐up we added fatigue level at baseline and relapse since baseline.

 Results: Higher tumour grade and insomnia predicted higher levels of fatigue, whereas better emotional functioning was associated with lower levels. After 12 months of follow‐up fatigue levels were associated with level at baseline and with emotional functioning, insomnia, relapse and being on sick leave or unemployed. Emotional level, insomnia and high grade were associated with level of fatigue. After 1 year, a high level at baseline, insomnia and low emotional functioning was associated with greater fatigue.

 Conclusions: These longitudinal results support that cancer‐related fatigue can be a persistent phenomenon and that focus on psychological distress and sleeping problems might be beneficial in these women. Copyright © 2010 John Wiley & Sons, Ltd.
Ku86 is important for TrkA overexpression‐induced breast cancer cell invasion
Authors: Lagadec Chann , Romon Rodrigue , Tastet Christophe , Meignan Samuel , Com Emmanuelle , Page Adeline , Bidaux Gabriel , Hondermarck Hubert , Le Bourhis Xuefen
Published: March 2010

Purpose: We have recently shown that breast tumors express high levels of TrkA compared with normal breast tissues, with TrkA overexpression enhancing breast cancer cell invasion in vitro and metastasis in animal models. In this study, we tried to identify molecules involved in TrkA overexpression‐mediated biological effects in breast cancer cells.

Experimental design: We used a proteomic‐based approach to identify proteins involved in TrkA overexpression‐stimulated invasion of MDA‐MB‐231 breast cancer cells. Proteins from control and TrkA overexpressing cells were separated using a cup‐loading two‐dimensional electrophoresis system before MALDI and LC‐MS/MS mass spectrometry analysis.

Results: Among several putative regulated proteins, Ku86 was found increased in TrkA overexpressing cells. Moreover, Ku86 was co‐immunoprecipitated with TrkA, suggesting the interaction of these two proteins in TrkA overexpressing cells. Interestingly, inhibition with small‐interfering RNA and neutralizing antibodies showed that Ku86 was required for TrkA‐stimulated cell invasion.

Conclusions and clinical relevance: These data allowed the identification of Ku86 as a new player involved in metastasis in breast cancer cells. Our findings suggest that TrkA and its down stream signaling pathways should be regarded as potential new targets for the development of future breast cancer therapy.
Preferential expression of IGF‐1Ec (MGF) transcript in cancerous tissues of human prostate: Evidence for a novel and autonomous growth factor activity of MGF E peptide in human prostate cancer cells
Authors: Armakolas Athanasios , Philippou Anastassios , Panteleakou Zacharoula , Nezos Adrianos , Sourla Antigone , Petraki Constantina , Koutsilieris Michael
Published: March 2010

BACKGROUND

By alternative splicing the IGF‐1 gene produces several different transcripts, including IGF‐1Ec (MGF). The latter has been mainly associated with muscle regeneration processes.

METHODS

We used immunohistochemistry, RT‐PCR, and Western analysis to show the expression status of MGF in prostate tissue and human prostate cell lines (HPrEC, PC‐3, and LNCaP) and we studied the exogenous administration of the MGF peptide E on cellular proliferation using trypan blue and MTT assays, before and after the silencing of the IGF‐1 receptor and insulin receptor (siRNA methods). The MGF‐induced intracellular activation was examined by Western analysis of the active forms of ERK1/2 and Akt.

RESULTS

We documented that MGF is overexpressed in human prostate cancer (PCa) tissues and in human PC‐3 and LNCaP cells. Notably, MGF expression was remarkably higher in PCa and prostatic intraepithelial neoplasia (PIN) than normal prostate tissues, while the normal prostate epithelial cells (HPrEC) did not express MGF. Exogenous administration of a synthetic MGF E peptide stimulated the PCa cell growth and activated ERK1/2 phosphorylation without affecting Akt phosphorylation. IGF‐1R or insulin receptor (IR) silencing did not affect the mitogenic activity and intracellular signaling of the MGF E peptide in these PCa cells.

CONCLUSIONS

These data suggest the possible implication of MGF E peptide in cancer biology, implying a preferential MGF expression in PCa tissues and cells. This preferential IGF‐1 mRNA expression generates the MGF E peptide that possesses mitogenic activity through mechanisms independent of IGF‐1R, IR, and hybrid IGF‐1R/IR. Prostate 70: 1233–1242, 2010. © 2010 Wiley‐Liss, Inc.
The burden of out‐of‐pocket and indirect costs of prostate cancer
Authors: Jayadevappa Ravishankar , Schwartz J. Sanford , Chhatre Sumedha , Gallo Joseph J. , Wein Alan J. , Malkowicz S. Bruce
Published: March 2010

BACKGROUND

Out‐of‐pocket and indirect (OPI) costs play an important role in prostate cancer (PCa) outcomes research. We sought to analyze OPI costs of newly diagnosed PCa patients receiving either radical prostatectomy (RP) or external beam radiation therapy (EBRT).

METHODS

Prospective cohort design was used to recruit 512 newly diagnosed PCa patients from urology clinics of an urban academic hospital and a Veterans Administration medical center. Participants provided demographic information and completed self‐reported generic and prostate‐specific Health Related Quality of Life (HRQoL) and indirect‐cost surveys at baseline and at 3, 6, 12, and 24 months follow‐up. Linear mixed models were applied to study the association between OPI costs, treatment and HRQoL outcomes. Propensity scores adjusted for potential confounders and Bonferroni correction was used to account for multiple testing.

RESULTS

Total mean OPI costs varied between RP group and EBRT group at 3‐month ($5576 vs. $2010), 6‐month ($1776 vs. $2133), 12‐month ($757 vs. $774), and at 24‐month follow‐up ($458 vs. $871). Linear mixed models indicated that RP was associated with lower medication costs (OR = 0.61, CI = 0.48–0.89) and total OPI costs (OR = 0.71, CI = 0.64–0.92). Total OPI costs were inversely related to most of the generic HRQoL items. Similarly, prostate‐specific HRQoL items of urinary function (OR = 0.72; adjusted‐CI = 0.58–0.84), bowel function (OR = 0.96; adjusted‐CI = 0.78–0.98), sexual function (OR = 0.85; adjusted‐CI = 0.72–0.92), urinary bother (OR = 0.79; adjusted‐CI = 0.67–0.83), and sexual bother (OR = 0.88; adjusted‐CI = 0.76–0.93) were inversely related to OPI costs.

CONCLUSIONS

OPI costs of PCa care are substantial and vary across time and treatment. Prostate 70: 1255–1264, 2010. © 2010 Wiley‐Liss, Inc.
Ultrathin magnesia films as support for molecules and metal clusters: Tuning reactivity by thickness and composition
Authors: Vaida Mihai E. , Bernhardt Thorsten M. , Barth Clemens , Esch Friedrich , Heiz Ueli , Landman Uzi
Published: March 2010

Ultrathin metal oxide films have attracted considerable interest in recent years as versatile substrate for the design of nanocatalytic model systems. In particular, it has been proposed theoretically and confirmed experimentally that the electronic structure of adsorbates can be influenced by the layer thickness and the stoichiometry, i.e., the type and number of defects, of the oxide film. This has important consequences on the chemical reactivity of the oxide surface itself and of oxide supported metal clusters. It also opens new possibilities to influence and to control chemical reactions occurring at the surface of these systems. The present feature focuses on very recent experiments that illustrate the effects of a proper adjustment of layer thickness and composition of ultrathin MgO(100) films on chemical transformations. On the magnesia surface itself, the photodissociation dynamics of methyl iodide molecules is investigated via femtosecond‐laser pump–probe mass spectrometry. Furthermore, the catalytic oxidation of carbon monoxide at mass‐selected Au20 clusters deposited on magnesia is explored through temperature programmed reaction measurements. In the latter case, detailed first principles calculations are able to correlate the experimentally observed reactivity with structural dimensionality changes that are induced by the changing thickness and composition of the magnesia support.

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Inverted optical phonons in II–VI semiconducting compounds
Authors: Vinogradov Evgeny , Mavrin Boris , Novikova Nadezhda , Yakovlev Vladimir
Published: March 2010

Additional optical phonons discovered in the majority of binary solid solution crystals of II–VI semiconductor compounds are discussed. Frequencies of these additional phonons are located inside the transverse–longitudinal splitting of the Γ point optical phonons, where the real part of the crystal permittivity is negative, and are split by the crystal field into transverse optical (TO) and longitudinal optical (LO) phonons, the frequencies of these additional LO phonons turning out to be lower than those of additional TO phonons.
Hybrid LEDs based on ZnO‐nanowire arrays
Authors: El‐Shaer Abdelhamid , Dev Apurba , Richters Jan‐Peter , Waldvogel Siegfried R. , Waltermann Julia , Schade Wolfgang , Voss Tobias
Published: March 2010

We report on room temperature electroluminescence from an inorganic/organic heterojunction light emitting diode based on ZnO nanowire arrays. The heterojunction is fabricated by depositing the p‐type polymer poly(3,4 ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) on n‐type ZnO nanowires grown by electrodeposition on transparent conducting glass (ITO) substrates. The nanowires are encapsulated in a thin polystyrene film deposited from high‐molecular‐weight solution. Electron injection occurs through the transparent ITO layer while hole injection is mediated by the PEDOT layer and gold contacts. The current–voltage (I–V) characteristics of the device shows a diode‐like behavior. A broad emission spectrum covering most of the visible range and reaching to the near ultraviolet is observed at voltages between 6 and 8 V under ambient condition. The device operation is stable for more than 5 h.
Schottky barrier contacts formed on polar and nonpolar MgxZn1−xO films grown by remote plasma enhanced MOCVD
Authors: Nakamura A. , Hayashi T. , Hierro A. , Tabares G. , Ulloa J. M. , Muñoz E. , Temmyo J.
Published: March 2010

The growth of MgxZn1−xO films of both polar and nonpolar orientation in was successfully carried out by remote‐plasma‐enhanced MOCVD (RPE‐MOCVD) technique. The polar face of as‐grown film had a vertically aligned columnar growth with respect to the sapphire (11–20) substrate. These columns had an average diameter of about 40 nm. In contrast, the nonpolar face of as‐grown film had a sword‐shape lying with an average width of 250 nm on the sapphire (10–12) substrate. Au/Schottky diodes (SDs) were fabricated on both polar face of c‐plane (0001) MgxZn1−xO and nonpolar face of a‐plane (11–20) MgxZn1−xO. A rectifying behavior had been achieved and a series resistance was increased with Mg contents in both polar and nonpolar diodes. A residual electron concentration was decreased with the Mg content from 3 × 1017 cm−3 at x = 0 to 1.2 × 1016 cm−3 at x = 0.18 in the case of nonpolar films.
A relationship between atomic correlation energy of neutral atoms and generalized entropy
Authors: Grassi A.
Published: March 2010

In a previous article, hereafter named as Paper I, we have showed a relationship between atomic correlation energy of neutral atoms with 2 < Z < 29 and Tsallis entropy. In this article, we generalize this relation showing the link between the atomic correlation energy and a general form of entropy obtained from deformed algebra. The results evidence the role of both q and Δ parameters of the general entropy, in terms of contribution of the long‐range interactions in the correlation energy. The q and Δ values, obtained as best fit of the atomic correlation energies 2 < Z < 29, indicate that this general form of entropy reduces to the Tsallis one, reproducing well the trend of the correlation energy for low Z. Moreover, as a consequence of these values of the parameters, the state atomic wave function is more localized with respect to the wave function calculated in the limit of Shannon entropy. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
A UV/VIS spectra investigation of pH‐sensitive dyes using time‐dependent density functional theory
Authors: Preat Julien , Jacquemin Denis , Perpète Eric A.
Published: March 2010

The UV absorption spectra of neutral and charged hydroxy‐, amino‐, benzene‐, naphtene, and quinoline derivated dyes are investigated with the PCM‐TDDFT/6‐311+g(2d,p)//PCM‐PBE0/6‐311g(d,p) theoretical scheme using three popular hybrid functionals (O3LYP, PBE0, and BHandHLYP) and taking into account solvation effects (water, methanol, or ethanol). More precisely, we report herein the theoretical λmax corresponding to the first dipole‐allowed π → π*. The raw results show that BHandHLYP is the less accurate (MAE of 36 nm) functional, though, after the statistical treatment, this hybrid becomes the most reliable and accurate functional for the evaluation of the absorption wavelengths. Indeed, the agreement between theory and experiment is satisfactory: The error on the excitation energies is close to 13 nm. In addition, our methodology has been applied to evaluate the UV spectra of nitrocatechol derivatives in aqueous solution, and the keto‐enol tautomeric shift on the UV/VIS absoprtion spectrum of a β‐diketone derivative. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2010