bluuebunny/crossref_metadata_2025 huggingface dataset:
Interventions for promoting the initiation of breastfeeding
Authors: Dyson L , McCormick F , Renfrew MJ
Published: August 2006

Background

Despite the widely documented health benefits of breastfeeding, initiation rates remain relatively low in many high‐income countries, particularly among women in lower income groups.

Objectives

To evaluate the effectiveness of interventions which aim to encourage women to breastfeed in terms of changes in the number of women who start to breastfeed.

Search strategy

We searched the Cochrane Pregnancy and Childbirth Group trials register (30 May 2004), the Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 1, 2003) and the following databases from inception to October 2002: MEDLINE, CINAHL, ERIC, Applied Social Sciences, PsychLIT, EMBASE, British Nursing Index, BIDS, EPI‐centre. We also searched the following in October 2002 for 'grey literature: 'SIGLE, DHSS Data, and Dissertation Abstracts. We handsearched the Journal of Human Lactation, Health Promotion International and Health Education Quarterly from inception to October 1998. We scanned reference lists of all articles obtained.

Selection criteria

Randomised controlled trials, with or without blinding, of any breastfeeding promotion intervention in any population group except women and infants with a specific health problem.

Data collection and analysis

One review author independently extracted data and assessed trial quality for checking by a second author. We contacted investigators to obtain missing information.

Main results

Seven trials involving 1388 women were included. Five trials involving 582 women on low incomes in the USA showed breastfeeding education had a significant effect on increasing initiation rates compared to routine care (relative risk (RR) 1.53, 95% confidence interval (CI) 1.25 to 1.88).

Authors' conclusions

Evidence from this review shows that the forms of breastfeeding education evaluated were effective at increasing breastfeeding initiation rates among women on low incomes in the USA.

Plain language summary

Forms of breastfeeding education evaluated are effective at increasing breastfeeding initiation rates among women on low incomes in the USA

Breastfeeding is widely known to be good for both the baby's and the mother's health. Despite this, many women choose not to breastfeed their baby, especially women living in countries or communities where breastfeeding is not common. This review aims to assess which breastfeeding promotion programmes are successful at increasing the numbers of women who start to breastfeed. Five programmes were found to show overall success at increasing the number of poorer women in the USA who started to breastfeed their baby. Copyright © 2006 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
Summary of ‘Antibiotics for acute pyelonephritis in children’
Authors: Milne Andrea
Published: August 2006

This is a summary of a Cochrane review, published in this issue of EBCH, first published as: Bloomfield P, Hodson EM, Craig JC. Antibiotics for acute pyelonephritis in children. Cochrane Database of Systematic Reviews 2005, Issue 1. Art. No.: CD003772. DOI: 10.1002/14651858.CD003772.pub2.

Further information for this Cochrane review is available in this issue of EBCH in the accompanying Expert Commentary and Characteristics and Key Findings Tables articles. Copyright © 2006 John Wiley & Sons, Ltd.
Characteristics and key findings for ‘Neuromuscular paralysis for newborn infants receiving mechanical ventilation’
Authors: van Dalen Elvira , Offringa Martin , Kremer Leontien
Published: August 2006

These are the characteristics and key findings for a Cochrane review, published in this issue of EBCH, first published as: Cools F, Offringa M. Neuromuscular paralysis for newborn infants receiving mechanical ventilation. Cochrane Database of Systematic Reviews 2005, Issue 2. Art. No.: CD002773. DOI: 10.1002/14651858.CD002773.pub2.

Further information for this Cochrane review is available in this issue of EBCH in the accompanying EBCH Summary and Expert Commentary articles. Copyright © 2006 John Wiley & Sons, Ltd.
Characteristics and key findings for ‘Vaccines for preventing influenza in healthy children’
Authors: van Dalen Elvira , Offringa Martin , Kremer Leontien
Published: August 2006

These are the characteristics and key findings for a Cochrane review, published in this issue, first published as: Smith S, Demicheli V, Di Pietrantonj C, Harnden AR, Jefferson T, Matheson NJ, Rivetti A. Vaccines for preventing influenza in healthy children. Cochrane Database of Systematic Reviews 2006, Issue 1. Art. No.: CD004879. DOI: 10.1002/14651858.CD004879.pub2.

Further information for this Cochrane review is available in this issue of EBCH in the accompanying EBCH Summary and Expert Commentary articles. Copyright © 2006 John Wiley & Sons, Ltd.
Commentary on ‘Vaccines for preventing influenza in healthy children’, with responses from the review authors and from the editors of Evidence‐Based Child Health
Authors: Booy Robert
Published: August 2006

This is a commentary on a Cochrane review, published in this issue of EBCH, first published as: Smith S, Demicheli V, Di Pietrantonj C, Harnden AR, Jefferson T, Matheson NJ, Rivetti A. Vaccines for preventing influenza in healthy children. Cochrane Database of Systematic Reviews 2006, Issue 1. Art. No.: CD004879. DOI: 10.1002/14651858.CD004879.pub2.

Further information for this Cochrane review is available in this issue of EBCH in the accompanying EBCH Summary and Characteristics and Key Findings Tables articles. Copyright © 2006 John Wiley & Sons, Ltd.
Design of an elliptic‐function bandpass filter using microstrip spiral resonators
Authors: Kawaguchi Tamio , Ma Zhewang , Kobayashi Yoshio
Published: August 2006

In this paper, a new equivalent circuit representation for the electromagnetic field coupling between distributed‐line resonators is discussed. Based on this circuit, the coupling coefficient is defined. In this definition, the coupling coefficient between resonators takes a positive, negative, or zero value. Hence, this equivalent circuit representation is useful in the design of multipole filters with poles in the stopband, in which positive and negative coupling are needed. Based on this definition, the design of an elliptic function four‐pole bandpass filter is carried out with the Sonnet em simulator and the effectiveness of the approach is discussed. © 2006 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 89(9): 1–10, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20252
Depth from defocus by zooming using thin lens‐based zoom model
Authors: Baba Masashi , Oda Ai , Asada Naoki , Yamashita Hideo
Published: August 2006

In past depth from zoom methods, the pinhole camera model has been used, and the depth has been measured by moving the pinhole position by zooming. This paper describes a method of estimating the depth from the change of blur depending on the zoom shift, in the same way as in the depth from focus/iris methods, where the depth is estimated from the change of blur. As the first step, a thin lens‐based zoom model is discussed, which describes in a unified way the relations among the zoom, focus, and iris of the zoom lens systems. In the proposed camera model, the effective focal length and the effective lens diameter are functions of the zoom, focus, and iris. The blur model is derived from these relations. Then, a method is described in which the depth is measured from the width of the edge blur. The experiment using a real image shows that it is possible to measure the depth stably from multizoom blur images. Lastly, we present an example in which the depth information obtained by the proposed method is applied to image synthesis. © 2006 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 89(9): 53–62, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20300
Synthesis of New Camptothecin Analogues with the E‐Lactone Ring Replaced by α,β‐Cyclohexenone
Authors: Bacherikov Valeriy A. , Tsai Tsong‐Jen , Chang Jang‐Yang , Chou Ting‐Chao , Lee Rong‐Zau , Su Tsann‐Long
Published: August 2006

The total synthesis of racemic camptothecin analogues 12a and 12b, in which the E‐lactone ring has been replaced by an α,β‐cyclohexenone ring and the ethyl and hydroxy substituents have been retained, was achieved by first preparing the ABCD fragments 31a and 31b, which were then converted into the tetracyclic triol 36a and 36b by osmium‐mediated dihydroxylation. Compounds 36a and 36b were oxidized in one‐pot reactions, followed by intramolecular aldol condensation to furnish the desired pentacyclic 12a and 12b, which retained topoisomerase I inhibitory activity and exhibited cytotoxicity to tumor cell growth in culture.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Electroanalysis of Bromate, Iodate and Chlorate at Tungsten Oxide Modified Platinum Microelectrode Arrays
Authors: Ordeig Olga , Banks Craig E. , Del Campo Fco. Javier , Muñoz Francesc Xavier , Compton Richard G.
Published: August 2006

This article describes the direct detection of Bromate, but also of chlorate and iodate, using modified arrays of platinum ultramicroelectrodes. The detection limits for these ions are IO$\rm{ {_{3}^{-}}}$=0.76 μM; BrO$\rm{ {_{3}^{-}}}$=2.34 μM and ClO$\rm{ {_{3}^{-}}}$=133.2 μM. The formation of a suitable tungsten oxide layer and the optimum analytical conditions are described. These oxide layers are formed electrochemically from hydrogen peroxide‐tungstanate solutions in acid conditions. Although film stability may be an issue, particularly at pH>3, these modified arrays of microelectrodes can be used for analytical purposes. After the analysis, the modifying oxide is easily removed and the Pt microelectrode array recovers its original properties.
Enantioselective, Potentiometric Memberane Electrodes Based on Different Cyclodextrins as Chiral Selectors for the Assay of S‐Flurbiprofen
Authors: Stefan‐van Staden Raluca‐Ioana , Bokretsion Rahel Girmai , Ozoemena Kenneth I , van Staden Jacobus Frederick , Aboul‐Enein Hassan Y.
Published: August 2006

Four enantioselective, potentiometric membrane electrodes (EPMEs) based on carbon paste impregnated with α‐, β‐, 2‐hydroxyl‐3‐trimethylammoniopropyl‐β‐(as chloride salt) and γ‐cyclodextrins, were proposed as a chiral selectors for assay of S‐flurbiprofen raw materials and in its pharmaceutical formulation Froben 100 tablets. The best response was obtained when β‐cyclodextrin was used for the electrode design. The four EPMEs showed very low detection limits (of 10−8 to 10−9 mol/L magnitude orders). The surfaces of the electrodes are easily renewable by simply polishing on an alumina paper.
A Bipartite Expression for the Transient Amperometric Current at a Membrane Covered Planar Electrode to Characterize Solute Diffusion Through the Membrane
Authors: Rong Zimei , Rashid Sarah , Vadgama Pankaj
Published: August 2006

A simple bipartite expression for transient amperometric currents at a membrane covered planar electrode has been derived. This expression is uniquely applicable across the entire measurement time frame and enables a rapid, comprehensive dynamic simulation of solute diffusion through the membrane barrier. The effective diffusion coefficient through the membrane for an electrochemically active solute can be readily obtained by employing the simple curve fitting routine. The diffusion coefficients for 4‐acetaminophenol through 0.05 and 0.025 μm pore diameter mixed cellulose esters membranes were determined to be 1.96×10−7 and 1.21×10−7 cm2/s, respectively. For catechol respective values were 1.55×10−7 and 1.15×10−7 cm2/s. Diffusion coefficients were reduced following membrane exposure to bovine serum albumin and this change provided a functional counterpart to conventional structural measures of surface biofouling. The approach has relevance to both sensors and membrane separation systems in biomedicine, and has the potential to offer a rapid assessment of membrane surface biofouling.
A Peroxidase‐Based Biosensor Supported by Nanoporous Magnetic Silica Microparticles for Acetaminophen Biotransformation and Inhibition Studies
Authors: Yu Donghui , Renedo Olga Dominguez , Blankert Bertrand , Sima Veronica , Sandulescu Robert , Arcos J. , Kauffmann Jean‐Michel
Published: August 2006

Magnetized nanoporous silica based microparticles (MMPs) were used for horseradish peroxidase (HRP) immobilization and applied for amperometric peroxidase‐based biosensor development. A magnetized carbon paste electrode permitted the MMPs attraction. The biosensor was applied to the investigation of the enzymatic oxidation of acetaminophen (paracetamol). The biosensor operated at low applied potential and the signal corresponded to the electroreduction of N‐acetylbenzoquinoneimine (NAPQI) generated by the enzyme HRP in the presence of hydrogen peroxide. The biosensor allowed performing the quantitation of acetaminophen in the micromolar concentration range and the comparative study of thiols which inhibited the biosensor response. Distinct inhibition results were observed for HRP entrapped in the silica microparticles compared to the soluble HRP.
Amperometric Electronic Tongue for the Evaluation of the Tea Astringency
Authors: Scampicchio Matteo , Benedetti Simona , Brunetti Barbara , Mannino Saverio
Published: August 2006

A new multi‐flow‐through amperometric detectors design was employed as a sensors array system for the detection of flavor related phenols. Relevant parameters of the amperometric detection were examined and optimized. The multivariate analytical signal was processed with chemometric analysis for exploring and classifying the tea beverages. Multivariate regression was used to correlate the astringency value of several tea beverages, obtained by the UNI (Italian Organization for Standardization) sensory profile test, with the signals collected by this amperometric electronic tongue.
Morphology of the Itapeva to Tramandai transgressive dunefield barrier system and mid‐ to late Holocene sea level change
Authors: Hesp Patrick A. , Dillenburg Sergio Rebello , Barboza Eduardo Guimaraes , Clerot Luiz C. P. , Tomazelli Luiz J. , Norberto Ayup Zouain Ricardo
Published: August 2006

The surface morphology of the transgressive dunefield barrier extending from Itapeva to Tramandai along the northern littoral of Rio Grande do Sul, is examined and an attempt is presented to link morphological changes across the barrier to Holocene sea level changes. The 4·5 km wide Holocene barrier displays two typical morphologies: an inner part dominated by large‐scale, continuous alongshore, overlapping dunefield phases comprising sand sheets, dunes, deflation plains and precipitation ridges; and an outer part dominated by discontinuous, medium‐ to small‐scale, triangular to lobate transgressive dunefield phases, cut by both active and relict (palaeo‐) creeks or washouts. Holocene sea level in the region rose to c. +1 to +3 m above present reaching a maximum around 5100 years bp and then progressively fell to the present level. We argue that the effect on barrier development was to suppress the development of a drainage system during the rising and maximum stages, and encourage the development of an organized drainage system in the form of regularly spaced washouts during the falling period, and that this change in sea level from rising to falling therefore produced the large‐scale differences in barrier morphology. Copyright © 2006 John Wiley & Sons, Ltd.
Temperature Dependence of Oxygen Reduction Catalyzed by Cobalt Fluoro‐Phthalocyanine Adsorbed on a Graphite Electrode
Authors: Song C. , Zhang L. , Zhang J. , Wilkinson D. P. , Baker R.
Published: August 2006

The graphite electrode surface onto which cobalt(II) 1,2,3,4,8,9,10,11,15,16,17,18,22,23,24,25‐hexadecafluoro‐29H,31H‐phthalo‐cyanine (abbreviated as CoIIHFPC) is adsorbed displays a strong electrocatalytic activity toward O2 reduction. The electrochemical response of surface adsorbed CoIIHFPC is investigated at different pHs and temperatures by cyclic voltammetry. The kinetics of the catalyzed O2 reduction at different temperatures, measured by cyclic voltammetric and rotating disk electrode methods, is analyzed and a corresponding reaction mechanism is proposed. A two‐electron/two‐proton process is found to be the dominating pathway for CoIIHFPC catalyzed O2 reduction. The increase in temperature, from 20 to 70 °C, enhances the reduction rate significantly. The presence of methanol has no effect on its catalytic activity towards O2 reduction. The implications of using this non‐noble electrocatalyst for the cathode reaction in low temperature fuel cells, including direct organic, metal‐air fuel cells, etc., are discussed in this paper.
Tubular Cathode Prepared by a Dip‐Coating Method for Low Temperature DMFC
Authors: Shao Z.‐G. , Lin W.‐F. , Zhu F. , Christensen P. A. , Zhang H.
Published: August 2006

A novel tubular cathode for the direct methanol fuel cell (DMFC) is proposed, based on a tubular titanium mesh. A dip‐coating method has been developed for its fabrication. The tubular cathode is composed of titanium mesh, a cathode diffusion layer, a catalyst layer, and a recast Nafion® film. The titanium mesh is present at the inner circumference of the diffusion layer, while the recast Nafion® film is at the outer circumference of the catalyst layer. A DMFC single cell with a 3.5 mgPt cm–2 tubular cathode was able to perform as well, in terms of power density, as a conventional planar DMFC. A peak power density of 9 mW cm–2 was reached under atmospheric air at 25 °C.
Accurate evaluation of the absorption maxima of retinal proteins based on a hybrid QM/MM method
Authors: Matsuura Azuma , Sato Hiroyuki , Houjou Hirohiko , Saito Shino , Hayashi Tomohiko , Sakurai Minoru
Published: August 2006

Here we improved our hybrid QM/MM methodology (Houjou et al. J Phys Chem B 2001, 105, 867) for evaluating the absorption maxima of photoreceptor proteins. The renewed method was applied to evaluation of the absorption maxima of several retinal proteins and photoactive yellow protein. The calculated absorption maxima were in good agreement with the corresponding experimental data with a computational error of <10 nm. In addition, our calculations reproduced the experimental gas‐phase absorption maxima of model chromophores (protonated all‐trans retinal Schiff base and deprotonated thiophenyl‐p‐coumarate) with the same accuracy. It is expected that our methodology allows for definitive interpretation of the spectral tuning mechanism of retinal proteins. © 2006 Wiley Periodicals, Inc. J Comput Chem, 2006
Computational study of the process of hydrogen bond breaking: The case of the formamide–formic acid complex
Authors: Pacios Luis F.
Published: August 2006

MP2/6‐311++G(d,p) and B3LYP/6‐311++G(d,p) quantum calculations are used to study the formamide–formic acid complex (FFAC), a system bound by two hydrogen bonds, NH···O and OH···O, that forms a bond ring at equilibrium. When the intermolecular separation between monomersRincreases, this ring opens at a distance for which the weaker NH···O bond breaks remaining the stronger OH···O bond. The computational study characterizes that process addressing changes of interaction energy ΔE, structure and properties of the electron density ρ(r) as well as spatial distributions of ρ(r), the electrostatic potentialU(r), and the electron localization function η(r). It is shown that the spatial derivatives of ΔE, the topology of ρ(r), and qualitative changes noticed inU(r) = 0 isocontours allow to identify a precise distanceRfor which one can say the NH···O hydrogen bond has broken. Both levels of theory predict essentially the same changes of structure and electron properties associated to the process of breaking and virtually identical distances at which it takes place. © 2006 Wiley Periodicals, Inc. J Comput Chem, 2006
Variation of atomic charges on proton transfer in strong hydrogen bonds: The case of anionic and neutral imidazole–acetate complexes
Authors: Pacios Luis F. , Gómez Pedro C. , Gálvez Oscar
Published: August 2006

The variation of atomic charges upon proton transfer in hydrogen bonding complexes of 4‐methylimidazole, in both neutral and protonated cationic forms, and acetate anion, is investigated. These complexes model the histidine (neutral and protonated)–aspartate pair present in active sites of proteases where strong NH···O hydrogen bonds are formed. Three procedures (Merz–Kollman scheme, Natural Population Analysis, and Atoms in Molecules Method) are used to compute atomic charges and explore their variation upon H‐transfer in the gas phase and in the presence of two continuum media with dielectric constants 5 (protein interiors) and 78.39 (water). The effect of electron correlation was also studied by comparing Hartree–Fock and MP2 results for both complexes in the gas phase. Greater net charge interchanged upon H‐transfer is observed in the anionic complex with respect to the neutral complex. Raising the polarity of the medium increases the amount of net charge transfer in both complexes, although the neutral system exhibits a larger sensitivity to the presence of solvent. Charge transfer associated to NH···O and N···HO bonds reveal the ionic contribution to the interaction depending on the number of charged subunits but the presence of solvent affects little this quantity. The lack of electron correlation overestimates all the charges as well as their variations and so uncorrelated calculations should be avoided. © 2006 Wiley Periodicals, Inc. J Comput Chem, 2006
The effect of the time and mode of application of gibberellic acid on the growth and yield of potato plants derived from true potato seed
Authors: Alexopoulos Alexios A , Akoumianakis Konstantinos A , Passam Harold C
Published: August 2006

The effect of the time and mode of treatment (single or repeated applications) of gibberellic acid (GA3) on the growth and tuberisation of plants grown from true seed (TPS) of potato Chacasina F1 was studied. Plant height, fresh and dry weight of stems and leaf dry weight increased in response to single or repeated GA3 applications. Leaf colour was not affected by single applications of GA3, whereas repeated applications caused a reduction in colour intensity. The numbers of secondary shoots and leaves per plant as well as total leaf area were largely unaffected by GA3, although repeated applications from early in the growth cycle increased these parameters under conditions of decreasing photoperiod. When applied as a single dose during spring, GA3 caused an increase in the number of tubers per plant, with a concomitant decrease in tuber dry matter content, irrespective of application date. In autumn the number of tubers per plant increased following single applications of GA3 up to 50 days after transplantation, whereas tuber dry matter decreased. By contrast, repeated applications of GA3 in both seasons increased tuber number only when initiated early in the growth cycle. The mean weight of tubers per plant was variably affected by GA3 application, depending on the season, time and mode of application. It is suggested that the foliar application of GA3 to plants from TPS at an early stage of vegetative development may be of value for seed tuber or micro‐tuber production, primarily by increasing the number of tubers produced per plant. Copyright © 2006 Society of Chemical Industry
Positive solutions and multiple solutions for periodic problems driven by scalar p ‐Laplacian
Authors: Hu Shouchuan , Papageorgiou N. S.
Published: August 2006

In this paper we study a nonlinear second order periodic problem driven by a scalar p ‐Laplacian and with a nonsmooth, locally Lipschitz potential function. Using a variational approach based on the nonsmooth critical point theory for locally Lipschitz functions, we first prove the existence of nontrivial positive solutions and then establish the existence of a second distinct solution (multiplicity theorem) by strengthening further the hypotheses. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Numerical algorithms for cyclic phase transformation hysteresis in a shape memory plate subject to axisymmetric plane stress
Authors: Chi Yuwei , Pence Thomas J. , Tsai Hungyu
Published: August 2006

We present numerical algorithms for calculating stress fields in an annulus composed of a shape memory material under conditions of quasi‐static edge loading at constant temperature. The algorithms track the material microstructure in terms of the volume fraction of austenite (A) and martensite (M), the latter of which provides a transformation strain. The dependence on load path imparts significant hysteresis in the stress induced transformation between A and M. A previous study that was restricted to proportional loading in the direction of forward transformation (J. Appl. Mech. 2005; 72:44–53) is here generalized to consider arbitrary loadings. The shooting algorithm that was robust for the previously considered proportional loadings is found to be subject to numerical instability for the most general transformation possibilities considered here. This motivates the development of an alternative iterated mapping algorithm that is found to generate a robust semi‐analytical finite difference procedure. The algorithm efficiently determines the operative transformation type, as is illustrated in cases where forward and reverse loading are occurring simultaneously at different plate locations. At those locations where phase transformation is inactive, the algorithm continues to account for martensite reorientation that alters the local transformation strain. Copyright © 2006 John Wiley & Sons, Ltd.
A generalization of the method of incompatible modes
Authors: Bischoff Manfred , Romero Ignacio
Published: August 2006

A generalization of the classical method of incompatible modes is presented, containing the original formulation as a special case. The method constitutes a class of finite elements which is equivalent to the class of enhanced assumed strain elements, yet based on a pure displacement formulation. Copyright © 2006 John Wiley & Sons, Ltd.
Finite element formulations for transient dynamic analysis in structural systems with viscoelastic treatments containing fractional derivative models
Authors: Cortés Fernando , Elejabarrieta María Jesús
Published: August 2006

This paper presents finite element formulations for transient dynamic analysis in structural systems with damping treatments in which viscoelastic materials are characterized by means of fractional derivative models. In contrast to other formulations, such as that of Padovan employing the principle of virtual work, the proposed formulations begin from the local equation of linear momentum and make use of the weighted residual method, providing a matrix equation of motion involving fractional operators. The numerical approximations of these are developed through the Grünwald–Letnikov definition, which allows to formulate explicit and implicit numerical schemes.

The principal advantage of the proposed formulations is that the history of the displacements and external forces must be stored, but not that of the stress, which reduces computational time and storage needs.

Numerical applications are presented for a cantilever beam, where a viscoelastic treatment has been applied using damping material modelled by a five‐parameter fractional derivative model. The results of the proposed formulation are compared among them and with those of Padovan for different damping values and for different load cases. The influence of the truncation of Grünwald coefficients and of the integration time‐step is also investigated. Copyright © 2006 John Wiley & Sons, Ltd.
Organic ion exchangers as beads. Synthesis, characterization and applications
Authors: Dragan E. S. , Avram E. , Dinu M. V.
Published: August 2006

Two less explored strategies in the preparation of porous organic ion exchangers in bead form are presented in this paper: the preparation of macroporous strong base anion exchangers with N,N‐diethyl‐2‐hydroxyethyl benzylammonium chloride units, a less explored chloromethylation reagent of the styrene‐divinylbenzene copolymers being used, and the preparation of anion exchangers with primary amine groups by the aminolysis‐hydrolysis reaction with 1,2‐diaminoethane of the nitrile groups, contained in some porous copolymers of acrylonitrile‐divinylbenzene, followed by the carboxymethylation of the primary amine groups to prepare chelating ion exchangers. The influence of porogen nature, monomers dilution and crosslinking degree on the properties of the ion exchangers was examined. Structural characterization, functionalization‐morphology correlations, the ion exchange properties, and potential applications for the ion exchangers thus prepared have been discussed. Copyright © 2006 John Wiley & Sons, Ltd.
Preparation of a highly luminescent nanocomposite by chelating copolymer
Authors: Wang Cheng‐Chien , Chen An‐Liu , Chen I‐Han
Published: August 2006

Highly luminescent hybrid CdS (diameter = 3–6 nm)/copolymer nanocomposites are prepared by using the soap‐free emulsion polymerization with chemical precipitation methods in this investigation. The core/shell type of ZnS/CdS nanoparticle on the shell layer of the copolymer microsphere can be obtained via the ion‐exchange method. The luminescent intensity and energy of the hybrid CdS/copolymer nanocomposite not only can be improved by increasing the pH value due to the surface passivated by the iminodiacetic acid sodium salt of the polymer side chain, but also can be enhanced by the higher band gap inorganic materials ZnS shell layer. In addition, the CdS nanoparticle passivated by inorganic shell ZnS is more robust than when organically passivation. Furthermore, these hybrid nanoparticles are easily employed to manufacture the transparent copolymer membrane at the film formation temperature (60°C), and they still keep their high luminescent property. Copyright © 2006 John Wiley & Sons, Ltd.
Synthesis and characterization of a π‐conjugated hybrid of oligothiophene and porphyrin
Authors: Oyaizu Kenichi , Hoshino Manabu , Ishikawa Masuhide , Imai Takuya , Yuasa Makoto
Published: August 2006

5‐(3‐Thienyl)‐10,15,20‐triethyl‐21H,23H‐porphine (H2(ttep)) was synthesized and characterized. Oxidative polymerization of H2(ttep) gave a novel oligomeric porphyrin linked at the 2,5‐positions of the thienyl group. Electric conductivity of 4 × 10−1 S/cm after I2 doping indicated that the oligomer had a π‐conjugated structure with a delocalization of π electrons over the thienylene backbone. PM3 calculations revealed a low HOCO‐LUCO gap, which was consistent with the relatively high electric conductivity. Regioregular (head‐to‐tail) structure was inferred from spectroscopic and calculational results. The pendant porphyrin groups formed a regular J‐type array along the thienylene backbone, which was indicated by a significant red shift of the Soret band maximum. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5403–5412, 2006
Electroluminescence from a conjugated polymer grafted with CdSe/ZnS: High brightness and improved efficiency
Authors: Chen Kuei‐Bai , Chen Ming‐Hwey , Yang Sheng‐Hsiung , Hsieh Chao‐Hsiang , Hsu Chain‐Shu , Chen Chia‐Chun , Chien Hsiao‐Ju
Published: August 2006

A new series of sulfide‐substituted poly(1,4‐phenylene vinylene) derivatives (S1PPV–S3PPV) with different composition ratios were successfully synthesized via the Gilch route. The CdSe/ZnS were grafted to the sulfur atoms by ligand exchange reaction. The grafted CdSe/ZnS contents were determined from TGA analysis to be from 4.6 to 37.8%. A new peak at 1151 cm−1 formed in FT‐IR after ligand exchange, which is attributed to the force formation between sulfur and CdSe. The GPC results show that the molecular weights of final polymers became higher after ligand exchange. Thin films of obtained polymers emitted bright green and yellow light with the max emission peak located from 546 to 556 nm. Double‐layer LEDs with an ITO/PEDOT/polymer/Ca/Al configuration were fabricated to evaluate the potential use of these polymers. The turn‐on voltages of the devices were about 4–5 V. As the CdSe/ZnS content increased in grafted polymers, the device performance was significantly enhanced as compared to pristine polymers. In the case of S3PPV, the double‐layer device showed a maximum luminance of 6073 cd/m2 with a current yield of 0.82 cd/A. The maximum luminance and current yield was enhanced to 13,390 cd/m2 and 2.25 cd/A by grafting CdSe/ZnS onto polymers. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5378–5390, 2006
A Plasma‐Deposited Surface for Cell Sheet Engineering: Advantages over Mechanical Dissociation of Cells
Authors: Canavan Heather E. , Cheng Xuanhong , Graham Daniel J. , Ratner Buddy D. , Castner David G.
Published: August 2006

Summary: Previously, we compared the release of cell sheets via low‐temperature liftoff from ppNIPAM treated surfaces to cell removal by enzymatic digestion and mechanical dissociation. We made two interesting observations, namely: 1) mechanical dissociation of cells from surfaces leaves behind a surface that promotes new cell growth, and 2) that ToF‐SIMS data from post‐mechanical dissociation surfaces differed from the other surfaces primarily due to the presence of hydrocarbon species and a fragment at m/z = 86 which could be attributed to either amino acids (leucine/isoleucine) or lipid molecules. In this study, we examine in detail the effect that mechanical dissociation has on cell removal. Using PCA of the ToF‐SIMS data, we observe a clear separation of the post‐mechanical dissociation surfaces from controls. We find that post‐mechanical dissociation surfaces are primarily characterized by the presence of high mass fragments (indicative of lipid molecules), and the absence of certain low mass fragments indicative of protein. These findings support the hypothesis that the process of mechanical disruption ruptures cell walls, leaving lipid molecules from the cell membrane on the surface.

Removal of adhered cultured cells by mechanical dissociation.

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Removal of adhered cultured cells by mechanical dissociation.
Plasma‐Aided Micro‐ and Nanopatterning Processes for Biomedical Applications
Authors: Sardella Eloisa , Favia Pietro , Gristina Roberto , Nardulli Marina , d'Agostino Riccardo
Published: August 2006

Summary: Micro‐ and nanofabrication methods are essential today in microelectronics, optoelectronics, catalysis, and analytics. Recent advances in biomaterials show that micro‐ and nanofeatures, either at the surface or embedded in materials, can drive specific responses both in in vivo and in vitro biological systems. With such an approach, scientists can understand better, and possibly exploit, biological responses stimulated by properly designed biomedical surfaces. Because of their versatility, plasma treatment, deposition, and etching processes are often part of procedures optimized to create micro‐ and nanofeatures of different shape, size, and position, onto and inside materials. Presented here are recent examples of such processes developed in our group for biomedical applications.

Residuals of self‐assembled polystyrene (PS) beads (600 ± 50 nm in diameter) on NH3 plasma‐treated PS substrate, after O2 plasma etching.

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Residuals of self‐assembled polystyrene (PS) beads (600 ± 50 nm in diameter) on NH3 plasma‐treated PS substrate, after O2 plasma etching.
From Single Particle Interactions to Bulk Powder Flow: Application to Uranium Oxide Powders
Authors: Quintanilla Miguel A. S. , George Matthieu , Goddard Dave T. , Semeraz J. Terry
Published: August 2006

The increase in computational power has made it possible to simulate the behaviour of granular materials in realistic situations. However there is a lack of knowledge of the values of the particle properties that are needed as input parameters to computer simulations for many materials used in the nuclear industry. The Atomic Force Microscope (AFM) is a good candidate tool for the measurement of individual particle properties.

In the study presented here, an AFM has been used to measure the interaction forces (normal or lateral) between particles and to characterise the topography of the contact areas, in the case of both model systems (spherical glass particles and planar mica surfaces) and industrially relevant systems involving irregular uranium oxide particles. It will be shown how these experiments provide useful information for the analysis of the flow properties of a powder.

The possible use of this experimental data in the simulation of bulk powder flowing behaviour will be discussed.
Characterization of the Dispersion Behavior of Powders in Liquids
Authors: Goalard Carol , Samimi Arezai , Galet Laurence , Dodds John A. , Ghadiri Mojtaba
Published: August 2006

Powders dispersed in liquids to form suspensions are widely used as food products, medications, and occur in many stages in industrial processes, whether as a final or an intermediate product. To maximize the efficiency of a dispersion process, a sound understanding of the factors that influence and limit the formation of suspensions is necessary. These involve wetting characteristics based on surface energy and also the physical form of the powders, such as particle size and the state of agglomeration. In this paper we examine the dispersion of talc powders either agglomerated in a conventional high‐shear granulator or agglomerated using a combined method of electro‐spray and freeze drying. The dispersion behavior of these agglomerates is studied as a function of the characteristics of the granules.
Catalytic growth of 0.4 nm single‐walled carbon nanotubes aligned inside porous zeolite crystals
Authors: Zhai J. P. , Tang Z. K. , Hu X. J. , Zhang X. X. , Sheng P.
Published: August 2006

We report our recent study on processes of decomposition of tripropylamine (TPA) molecules in the channels of AlPO4‐5 (AFI) and Co‐incorporated AlPO4‐5 (CoAPO‐5) zeolite crystals, by means of Fourier transform Infrared (FTIR) spectra and thermogravimetry (TG) techniques. In comparison with pure AlPO4‐5 crystals, the carbonization temperature of TPA molecules inside the channels of Co‐AFI crystals is notably decreased; indicating that Co atoms incorporated in the AFI framework plays an important catalyst role. These incorporated Co atoms are also favorable to the formation of the 0.4 nm single‐walled carbon nanotubes (SWNTs) in the channels, characterized by a significant decrease in nanotubes formation energy. The resulting SWNTs have higher filling density in the channels than that fabricated without catalyst Co. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Immobilization of CNFs on the surface and inside of the modified activated carbon
Authors: Chen X.‐W. , Su D. S. , Schlögl R.
Published: August 2006

The applications of carbon nanotubes or nanofibers (CNTs/CNFs) in chemistry and catalysis require the availability of large amount of materials with well‐defined surface, chemical and mechanical properties. Loose CNTs/CNFs are unsuitable as they cannot be controlled in their suprastructural properties and operations of compaction can destroy or at least inhibit the access of the reactant to the nanostructures. It is mandatory for chemical applications to use only one chemical element for all dimensions of structuring and to avoid the combination of nanocarbon with non‐carbon support structures. An ideal substrate is activated carbon (AC) from natural sources. Such bio‐inorganic polymers are well structured in several dimensions, reactive for modifications and available in masses. The present work describes the ways to modify the activated carbon obtained from the bio‐waste of palm oil production as host for the growth of nanocarbon. CNFs can be immobilized on the outer surface and nested inside of the activated carbon leading to hierarchically structured carbon materials that are highly suitable for sorption and catalytic applications and for binder‐filler applications. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Field emission induced deformations in SiO2 during CVD growth of carbon nanotubes
Authors: Svensson J. , Bulgakova N. M. , Nerushev O. A. , Campbell E. E. B.
Published: August 2006

The application of an electric field while growing carbon nanotubes with CVD can induce deformations in the SiO2 substrate. The effect is attributed to field emission from the tubes and Marangoni convection in a small molten SiO2 region underneath the tubes. Postgrowth deformation has been performed as well as large scale deformations using the collective effect of many field emitters. The porosity of one type of deformation is also examined and discussed. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
EPR characterization of catalyst‐free SWNT and N@C60‐based peapods
Authors: Corzilius B. , Gembus A. , Weiden N. , Dinse K.‐P. , Hata K.
Published: August 2006

Single Wall Carbon Nanotubes (SWNT) produced by “Super‐Growth” CVD technique show no evidence for non‐carbon impurities. At X‐Band frequencies an EPR signal from conduction electrons is observed at room temperature. At low temperatures the conduction electrons get trapped, leading to a sharp EPR signal with long‐lived spin states. Using multi pulse techniques the hyperfine interaction to 13C can be resolved. Using low temperature liquid phase filling techniques, it is possible to prepare N@C60@SWNT with filling efficiencies of a few percent. At elevated temperatures, the fullerenes show a quite mobile behavior, especially in SWNT of wide diameter. This motion continuously slows down at lower temperatures resulting in complete immobilization. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Determination of dichloroanilines in human urine by gas chromatography/mass spectrometry: validation protocol and establishment of Reference Values in a population group living in central Italy
Authors: Turci Roberta , Barisano Angelo , Balducci Claudio , Colosio Claudio , Minoia Claudio
Published: August 2006

3,4‐ and 3,5‐Dichloroanilines (DCAs) are common markers of some non‐persistent pesticides, e.g. linuron, diuron, vinclozolin, and iprodione. The general population may be exposed to these DCAs and/or their precursors mainly through diet. Since adverse effects on human health, such as endocrine disruption, have been reported, biological monitoring is essential for exposure assessment both of occupationally exposed subjects and of the general population. A highly sensitive and selective gas chromatography/mass spectrometry (GC/MS) method has been developed for the determination of 3,4‐ and 3,5‐DCAs in urine using 4‐chloro‐2‐methylaniline as an internal standard. The selected ion monitoring (SIM) mode was employed for quantitation of the analytes. The sample treatment procedure is simple and fast and no derivatization is required. The overall method was validated including uncertainty measurement. The limit of detection (LOD) and the lower limit of quantitation (LLOQ) were determined to be 0.005 and 0.010 µg/L for both analytes. The method was then applied to the establishment of reference values for a population group living in a rural area of central Italy (Novafeltria, Marche). A total of 151 out of 153 samples were found to be positive for 3,5‐DCA, and 81.7% were positive for 3,4‐DCA. For this group, 3,4‐DCA levels ranged from 0.01 to 6.19 µg/L, while 3,5‐DCA urinary concentrations were between 0.02 and 6.71 µg/L. Copyright © 2006 John Wiley & Sons, Ltd.
Regulation of the rat brain Na+‐driven exchanger involves protein kinase A and a multiprotein signaling complex
Authors: Lee Yong-Sun , Ouyang Yi-Bing , Giffard Rona G.
Published: August 2006

The Na+‐driven exchanger (NCBE) plays an important role in the regulation of intracellular pH (pHi). We previously identified two variants of NCBE from rat brain of which the variant with a carboxyterminal PSD‐95/Dlg/ZO‐1 (PDZ) motif (rb2NCBE) colocalized with the actin cytoskeleton. Increased rb2NCBE activity by PKA inhibition and reduction by forskolin and cAMP agonist suggest PKA regulation of NCBE. Disruption of actin filaments also decreased rb2NCBE activity. EBP50 and FLAG‐rb2NCBE were reciprocally co‐immunoprecipitated from rb2NCBE transfected cells. It is concluded that NCBE activity is inhibited by PKA and depends on the integrity of the actin cytoskeleton within a multiprotein complex at the plasma membrane.
Role of aquaporin‐7 in the pathophysiological control of fat accumulation in mice
Authors: Rodríguez Amaia , Catalán Victoria , Gómez-Ambrosi Javier , Frühbeck Gema
Published: August 2006

Aquaporins are channels that allow the movement of water across the cell membrane. Some members of the aquaporin family, the aquaglyceroporins, also allow the transport of glycerol, which is involved in the biosynthesis of triglycerides and the maintenance of fasting glucose levels. Aquaporin‐7 (AQP7) is a glycerol channel mainly expressed in adipocytes. The deletion of AQP7 gene in mice leads to obesity and type 2 diabetes. AQP7 modulates adipocyte glycerol permeability thereby controlling triglyceride accumulation and fat cell size. Furthermore, the coordinated regulation of fat‐specific AQP7 and liver‐specific AQP9 may be key to determine glucose metabolism in insulin resistance.
Cold acclimation of the Arabidopsis dgd1 mutant results in recovery from photosystem I‐limited photosynthesis
Authors: Hendrickson Luke , Vlčková Alexandra , Selstam Eva , Huner Norman , Öquist Gunnar , Hurry Vaughan
Published: August 2006

We compared the thylakoid membrane composition and photosynthetic properties of non‐ and cold‐acclimated leaves from the dgd1 mutant (lacking >90% of digalactosyl–diacylglycerol; DGDG) and wild type (WT) Arabidopsis thaliana. In contrast to warm grown plants, cold‐acclimated dgd1 leaves recovered pigment‐protein pools and photosynthetic function equivalent to WT. Surprisingly, this recovery was not correlated with an increase in DGDG. When returned to warm temperatures the severe dgd1 mutant phenotype reappeared. We conclude that the relative recovery of photosynthetic activity at 5 °C resulted from a temperature/lipid interaction enabling the stable assembly of PSI complexes in the thylakoid.