bluuebunny/crossref_metadata_2025 huggingface dataset:
ChemInform Abstract: Ruthenium N‐Heterocyclic Carbene Complexes in Organic Transformations (Excluding Metathesis)
Authors: Burling Suzanne , Paine Belinda M. , Whittlesey Michael K.
Published: December 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Structural Organozinc Chemistry
Authors: Jastrzebski Johann T. B. H. , Boersma Jaap , Van Koten Gerard
Published: December 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Determination of Fatty Acid Ethyl Esters (FAEE) and Ethyl Glucuronide (ETG) in Hair: A Promising Way for Retrospective Detection of Alcohol Abuse During Pregnancy?
Authors: Pragst Fritz , Yegles Michel
Published: December 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: The Influence of X‐Rays on the Structural Studies of Peroxide‐Derived Myoglobin Intermediates
Authors: Hersleth Hans‐Petter , Hsiao Ya‐Wen , Ryde Ulf , Goerbitz Carl Henrik , Andersson K. Kristoffer
Published: December 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Molecularly Imprinted Polymer as a Solid Phase Extractor in Flow Analysis
Authors: Dias A. C. B. , Figueiredo E. C. , Grassi V. , Zagatto E. A. G. , Arruda M. A. Z.
Published: December 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Hyphenated Chromatographic Techniques in Nuclear Magnetic Resonance Spectroscopy
Authors: Eldridge Stacie L. , Korir Albert K. , Merrywell Christiana E. , Larive Cynthia K.
Published: December 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Functional Proteomics on Zinc‐Dependent Metalloproteinases using Inhibitor Probes
Authors: Klein Theo , P. Geurink Paul , S. Overkleeft Hermen , K. Kauffman Henk , Bischoff Rainer
Published: December 2008

Zinc‐dependent metalloproteinases such as matrix metalloproteinases (MMPs) and A disintegrin and metalloproteinases (ADAMs) are potential therapeutic targets in many diseases. To better understand their complex role in health and disease, new methodology for activity determination is under development. This concept gives an overview of the available methods for activity‐based proteomic research on these enzymes.

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Metzincins are a family of zinc(II)‐dependent metalloproteinases with well known members such as the matrix metalloproteinases (MMPs) and A disintegrin and metalloproteinases (ADAMs). Metzincins are largely responsible for the modulation and regulation of the extracellular matrix by proteolytic degradation of extracellular matrix (ECM) proteins, and by liberation or production of biologically active proteins from their pro‐forms. Since metzincin activity is strictly regulated in vivo, novel analysis methods are necessary to elucidate the role of the active enzymes in health and disease. This concept gives an overview of available methods, and describes an approach to use synthetic metzincin inhibitors as affinity probes for selective determination of active metzincins in biological and clinical samples.
Incorporation of an apoE‐derived lipopeptide in high‐density lipoprotein MRI contrast agents for enhanced imaging of macrophages in atherosclerosis
Authors: Chen Wei , Vucic Esad , Leupold Eik , Mulder Willem J. M. , Cormode David P. , Briley‐Saebo Karen C. , Barazza Alessandra , Fisher Edward A. , Dathe Margitta , Fayad Zahi A.
Published: December 2008

Magnetic resonance (MR) imaging is becoming a pivotal diagnostic method to identify and characterize vulnerable atherosclerotic plaques. We previously reported a reconstituted high‐density lipoprotein (rHDL) nanoparticle platform enriched with Gd‐based amphiphiles as a plaque‐specific MR imaging contrast agent. Further modification can be accomplished by inserting targeting moieties into this platform to potentially allow for improved intraplaque macrophage uptake. Since studies have indicated that intraplaque macrophage density is directly correlated to plaque vulnerability, modification of the rHDL platform may allow for better detection of vulnerable plaques. In the current study we incorporated a carboxyfluoresceine‐labeled apolipoprotein E‐derived lipopeptide, P2fA2, into rHDL. The in vitro macrophage uptake and in vivo MR efficacy were demonstrated using murine J774A.1 macrophages and the apolipoprotein E knock‐out (apoE−/−) mouse model of atherosclerosis. The in vitro studies indicated enhanced association of murine macrophages to P2fA2 enriched rHDL (rHDL–P2A2) nanoparticles, relative to rHDL, using optical techniques and MR imaging. The in vivo studies showed a more pronounced and significantly higher signal enhancement of the atherosclerotic wall 24 h after the 50 µmol Gd/kg injection of rHDL–P2A2 relative to administration of rHDL. The normalized enhancement ratio for atherosclerotic wall of rHDL–P2A2 contrast agent injection was 90%, while that of rHDL was 53% 24 h post‐injection. Confocal laser scanning microscopy revealed that rHDL–P2A2 nanoparticles co‐localized primarily with intraplaque macrophages. The results of the current study confirm the hypothesis that intraplaque macrophage uptake of rHDL may be enhanced by the incorporation of the P2fA2 peptide into the modified HDL particle. Copyright © 2008 John Wiley & Sons, Ltd.
Performance of a high‐continuity finite element in three‐dimensional elasticity
Authors: Bilotta Antonio , Formica Giovanni , Turco Emilio
Published: December 2008

We test the performance of a three‐dimensional finite element, named HC3 , which generalizes the high‐continuity (HC) finite element proposed by Aristodemo in 1985 for two‐dimensional elastic problems. The HC3 finite element is based on a quadratic B‐spline interpolation of the displacement field in three‐dimensional linear elasticity. The main feature of this interpolation technique, which can be considered as a particular case of the Bézier interpolation, consists in its capability in reproducing displacement fields of 𝒞1 smoothness with a computational cost equivalent to a linear interpolation, i.e. with a single knot for each element. Copyright © 2008 John Wiley & Sons, Ltd.
Optimal solution of a diffusion equation with a discrete source term
Authors: Araújo A. , Patrício F. , Santos José L.
Published: December 2008

In this paper we study the numerical behavior of a diffusion equation with a discrete control source term. The equation is discretized in space by finite differences and in time by an implicit scheme. The control variables are calculated in order to minimize an objective function, taking into account some restrictions. We define two strategies to obtain the optimal solution, with and without time dependence. For the time‐independent case we present a theoretical result that characterizes the optimal solution. Some numerical results are presented in a context of a model that describes the oxygen concentration in a single chamber microbial fuel cell. A generalization of these results for the two‐dimensional model is also considered. Copyright © 2008 John Wiley & Sons, Ltd.
Synthesis of ZnO nanostructures composed of nanosheets with controllable morphologies
Authors: Wang Ning , Jiang Li , Peng Hongrui , Li Guicun
Published: December 2008

ZnO nanostructures composed of nanosheets have been synthesized by a facile low temperature reaction of Zn(OH)2 and NaOH without the aid of any organic molecular templates. The influences of the reaction parameters, such as the concentrations of Zn(NO3)2, reaction temperatures, and reaction time on the morphologies of ZnO have been investigated. The thickness of ZnO nanosheets can be adjusted from 10–20 nm to 30–40 nm by altering the reaction temperatures from 80 °C to 180 °C. ZnO nanosheets are single crystals and the growth direction is perpendicular to [1100]. A possible gradual nucleation – rapid growth formation mechanism of ZnO nanosheets is proposed. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Simulation Study on the Control of the Ion Current Oscillation Based on the Ion Transport in Hall Thrusters
Authors: Yamamura Y. , Nejoh Y. N. , Yamaguchi H.
Published: December 2008

Simulation on the control of the ion current oscillation is performed by introducing the effect of the Xe ion transport in plasmas produced in the channel of Hall thrusters. Numerical results are in good agreement with the preceded experimental observations. It is shown for the first time that the ion current becomes stable and the thrust efficiency is improved when the ion mobility and the cross sectional area decrease. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Investigation of the Start Transient in a Hall Thruster
Authors: Liu H. , Yu D. R. , Yan G. J. , Liu J. Y.
Published: December 2008

A two dimensional axisymmetric fully kinetic Particle‐in‐Cell/Monte Carlo Collision (PIC‐MCC) model is used to describe the ignition process in a Hall thruster. A current peak and latter the periodic oscillation of current and electric potential are found. The corresponding evolutions of plasma density, electric potential and atom density during the ignition process are introduced in the paper. In addition, influences of mass flow rate and discharge potential on current peak are modeled and analyzed. The simulated results are consistent with former experimental results. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effect of Oscillating Sheath on Near‐Wall Electron Current Profile in Hall Thrusters
Authors: Yu D. R. , Liu H. , Ning Z. X. , Yan G. J.
Published: December 2008

The radial profile of the axial electron current in Hall thrusters was measured; however, the significant decay of the current density peak in the near‐wall region can't be explained effectively by the steady sheath theory. As the sheath exhibits an oscillating character when the thruster is in operation, its effect on the near‐wall current profile has been studied in this paper. To obtain a comprehensive knowledge, we have considered a wide sheath oscillation frequency span which includes two asymptotic frequency cases at high and low ends. Based on the case studied, either an analytical treatment or a numerical simulation is applied. The results show that the current density peak has a fastest damping speed away from the wall at the asymptotic low frequency. With the increase of the frequency, both the decay and the spatial “wavelength” of the current profile decrease. The decay finally disappears at the asymptotic high frequency with a constant spatial “wavelength”. Moreover, the sheath oscillation amplitude can enhance the decay and enlarge the spatial “wavelength”. Taking into account of the realistic situation in Hall thrusters, the significant impact of the oscillating sheath on the near‐wall electron current profiles can be anticipant. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Thermodynamics and Phase Transitions in Dense Hydrogen – the Role of Bound State Energy Shifts
Authors: Ebeling W. , Redmer R. , Reinholz H. , Röpke G.
Published: December 2008

In recent papers we have investigated the effects of Pauli blocking on the energy shifts in dense hydrogen. As Pauli blocking we denote effects on the shifts which result from the antisymmetry of the electronic wave functions. Here we study of the thermodynamic properties of dense hydrogen including the influence of energy shifts. Of special interest is the region where a transition from insulating behavior to metal‐like conductivity has been shown experimentally. In this region, Pauli blocking effects have a deciding influence on this transition. Assuming that the system is a gas‐like mixture of chemical species, the ionization equilibrium is treated by an advanced chemical approach. We calculate the Pauli and Fock shifts by perturbation theory and variational methods and construct useful interpolation formulae. Results for the ionization equilibrium are presented for temperatures between 4 000 K < T < 20 000 K and densities in the range n = (2–6) × 1023cm–3 where the transition from a neutral hydrogen gas to a highly ionized plasma occurs. The results for the equation of state and the relative pressure indicate that the transition to a highly conducting state is softer than derived in earlier work. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Prediction of flocculation ability of brewing yeast inoculates by flow cytometry, proteome analysis, and mRNA profiling
Authors: Heine Franziska , Stahl Frank , Sträuber Heike , Wiacek Claudia , Benndorf Dirk , Repenning Cornelia , Schmidt Frank , Scheper Thomas , von Bergen Martin , Harms Hauke , Müller Susann
Published: December 2008

The ability of brewing yeast to flocculate is an important feature for brewing of qualitatively good beer. Flocculation involves two main cell wall structures, which are the flocculation proteins (flocculins) and mannans, to which these flocculins bind. Unfortunately, in practice, the flocculation ability may get lost after several repitches. Flow cytometry was employed to analyze glucose and mannose structures of the cell surface by application of fluorescent lectins. Validation of the expression of the flocculin genes Lg‐FLO1, FLO1, FLO5, and FLO9 was carried out using microarray techniques. SDS‐PAGE, western blot, and ESI‐MS/MS analyses served to isolate and determine yeast cell flocculins. Mannose and glucose labeling with fluorescent lectins allowed differentiating powdery and flocculent yeast cells under laboratory conditions. Using microarray techniques and proteomics, the four flocculation genes Lg‐FLO1, FLO1, FLO5, FLO9, and the protein Lg‐Flo1p were identified as factors of major importance for flocculation. The expression of the genes was several times higher in flocculent yeast cells than in powdery ones. Flow cytometry is a fast and simple method to quantify the proportions of powdery and flocculent yeast cells in suspensions under defined cultivation conditions. However, differentiation under industrial conditions will require mRNA and protein expression profiling. © 2008 International Society for Advancement of Cytometry
Supercontinuum white light lasers for flow cytometry
Authors: Telford William G. , Subach Fedor V. , Verkhusha Vladislav V.
Published: December 2008

Excitation of fluorescent probes for flow cytometry has traditionally been limited to a few discrete laser lines, an inherent limitation in our ability to excite the vast array of fluorescent probes available for cellular analysis. In this report, we have used a supercontinuum (SC) white light laser as an excitation source for flow cytometry. By selectively filtering the wavelength of interest, almost any laser wavelength in the visible spectrum can be separated and used for flow cytometric analysis. The white light lasers used in this study were integrated into a commercial flow cytometry platform, and a series of high‐transmission bandpass filters used to select wavelength ranges from the blue (∼480 nm) to the long red (>700 nm). Cells labeled with a variety of fluorescent probes or expressing fluorescent proteins were then analyzed, in comparison with traditional lasers emitting at wavelengths similar to the filtered SC source. Based on a standard sensitivity metric, the white light laser bandwidths produced similar excitation levels to traditional lasers for a wide variety of fluorescent probes and expressible proteins. Sensitivity assessment using fluorescent bead arrays confirmed that the SC laser and traditional sources resulted in similar levels of detection sensitivity. Supercontinuum white light laser sources therefore have the potential to remove a significant barrier in flow cytometric analysis, namely the limitation of excitation wavelengths. Almost any visible wavelength range can be made available for excitation, allowing access to virtually any fluorescent probe, and permitting “fine‐tuning” of excitation wavelength to particular probes. © 2008 International Society for Advancement of Cytometry
Close association of CD8+/CD38bright with HIV‐1 replication and complex relationship with CD4+ T‐cell count
Authors: Tuaillon Edouard , Al Tabaa Yassine , Baillat Vincent , Segondy Michel , Picot Marie‐Christine , Reynes Jacques , Vendrell Jean‐Pierre
Published: December 2008

Background:

Measuring lymphocyte activation provides information in addition to CD4+ T‐cell count for immune monitoring of HIV‐1 infected patients. CD38 is a well‐established activation marker that is generally analyzed on the whole population of CD8+ T‐cells. Focusing specifically on CD38 high expression (CD8+/CD38bright) may be an interesting surrogate gating strategy because CD38bright characterizes principally activated memory cells.

Methods:

CD8+/CD38bright was investigated in 1,353 HIV‐1 infected patients over a one‐year period to establish relevant cutoff values and clarify the relationships of this marker with HIV‐1 RNA viral load (VL) and CD4+ T‐cell count.

Results:

The CD8+/CD38bright (>8,500 CD38 binding site per cells) is well correlated with HIV‐1 VL (r = 0.87, P < 0.001) in this longitudinal follow‐up of nonimmunodepressed patients that initiated antiviral therapy (ART). In aviremic patients on ART, the marker was highly predictive of VL rebound (sensitivity 93%, specificity 64% for a VL level of detection >200 copies/ml). While the CD8+/CD38bright moderately correlated with CD4+ T‐cell count independently of the VL (r = −0.37, P < 0.001), it increased dramatically in aviremic patient groups that exhibited profound CD4+ T‐cell depletion (median 39% for CD4+ T‐cell counts <50/mm3). This result indicates that other additional immunological and/or viral factors than readily detectable HIV‐1 replication appears to be involved in T‐cell activation of immunodepressed individuals.

Conclusions:

CD8+/CD38bright is an effective marker for monitoring T‐cell activation, which is a central factor of HIV‐1 pathogenesis. This gating strategy requires only a single additional staining in conventional four color CD4 protocols. © 2008 Clinical Cytometry Society
Cognitive neuroscience of Attention Deficit Hyperactivity Disorder: Current status and working hypotheses
Authors: Vaidya Chandan J. , Stollstorff Melanie
Published: December 2008

Cognitive neuroscience studies of Attention Deficit Hyperactivity Disorder (ADHD) suggest multiple loci of pathology with respect to both cognitive domains and neural circuitry. Cognitive deficits extend beyond executive functioning to include spatial, temporal, and lower‐level “nonexecutive” functions. Atypical functional anatomy extends beyond frontostriatal circuits to include posterior cortices, limbic regions, and the cerebellum. Pathophysiology includes dopaminergic as well as noradrenergic neurotransmitter systems. We review the major insights gained from functional brain imaging studies in ADHD and discuss working hypotheses regarding their neurochemical underpinnings. © 2008 Wiley‐Liss, Inc. Dev Disabil Res Rev 2008;14:261–267.
The neurobiological profile of girls with ADHD
Authors: Mahone E. Mark , Wodka Ericka L.
Published: December 2008

Since boys are more commonly diagnosed with Attention Deficit Hyperactivity Disorder (ADHD) than girls, the majority of theories and published research studies of ADHD have been based on samples comprised primarily (or exclusively) of boys. While psychosocial impairment in girls with ADHD is well established, the neuropsychological and neurobiological basis of these deficits is less consistently observed. There is growing evidence that boys' and girls' brains develop and mature at different rates, suggesting that the trajectory of early anomalous brain development in ADHD may also be sex‐specific. It remains unclear, however, whether earlier brain maturation observed in girls with ADHD is protective. In this review, we outline the current theory and research findings that seek to establish a unique neurobiological profile of girls with ADHD, highlighting sex differences in typical brain development and among children with ADHD. The review highlights findings from neurological, neurocognitive, and behavioral studies. Future research directions are suggested, including the need for longitudinal neuroimaging and neurobehavioral investigation beginning as early as the preschool years, and continuing through adolescence and adulthood, with consideration of identified sex differences in the development of ADHD. © 2008 Wiley‐Liss, Inc. Dev Disabil Res Rev 2008;14:276–284.
Aktuelle europäische Rechtsänderungen – ein kurzer Überblick
Authors: Abend Kerstin
Published: December 2008

Der europäische Gesetzgeber hat in jüngster Zeit verschiedenste Rechtsänderungen auf den Weg gebracht, die sich unmittelbar auf den Baubereich auswirken. So ist ein “Binnenmarktpaket für Waren” mit zwei Verordnungen und einem Beschluss verabschiedet worden, überwiegend anwendbar ab 2010, teils ab Mai 2009. Gleichzeitig wird die Bauproduktenrichtlinie überarbeitet. Sie soll durch eine europäische Bauprodukteverordnung, voraussichtlich ab Juli 2011, ersetzt werden. Ein entsprechender Kommissionsvorschlag ist noch in der Diskussion. Nachfolgend werden ein kurzer Überblick über die neue Rechtslage, deren wichtigsten Auswirkungen im Baubereich sowie eine Zwischeninformation über die Arbeiten zum Vorschlag der Kommission für eine Bauprodukteverordnung gegeben sowie eine Stellungnahme des Bundesrates zum Kommissionsvorschlag abgedruckt.
(1,3,4‐Oxadiazole)copper(II) Compounds: Dimensionality, Magnetism and Nuclease Activity
Authors: Gómez‐Saiz Patricia , Gil‐García Rubén , Maestro Miguel A. , Arnaiz Francisco J. , Lezama Luis , Rojo Teófilo , Pizarro José Luis , Arriortúa María Isabel , González‐Álvarez Marta , Borrás Joaquín , Diez‐Gómez Virginia , García‐Tojal Javier
Published: December 2008

The work presented here describes the synthesis of new copper(II) complexes derived from 2‐amino‐5‐(pyridin‐2‐yl)‐1,3,4‐oxadiazole (L1) and 2‐methylamino‐5‐(pyridin‐2‐yl)‐1,3,4‐oxadiazole (L2) which also incorporate azido (N3–),thiocyanato (NCS–), cyanato (NCO–), dicyanamido [N(CN)2–, dca] and malonato (C3H2O42–, mal) coligands. Structures of the [Cu(L2)(mal)(H2O)]·2H2O (1), [{Cu(L2)(mal)}2] (2), [Cu(L2)2(NCS)2] (3), [Cu(L1)(NCS)2]n (4) and [{Cu(L2)}2(dca)2](ClO4)2·2H2O (5) compounds show the dependence of the dimensionality on parameters such as the type of oxadiazole and coligand utilised, solvents or reaction times. In this sense, 1 and 3 are mononuclear complexes, 2 contains centrosymmetric dinuclear entities, 4 is a 1D compound in which thiocyanato groups act as end‐to‐end bridges and 5 shows a 2D arrangement of dinuclear motifs linked through dicyanamido spacers. The copper(II) ions acquire distorted octahedral (3 and 4), square‐pyramidal (1 and 2) and trigonal bipyramidal (5) geometries. Stacking π–π interactions and hydrogen bonds stabilise the crystal frameworks. Water tetramers are present in 1. Spectroscopic (infrared, UV/Vis absorption and electron spin resonance) studies have also been developed for 1–5 and for the Cu(L2)(dca)2(H2O) (6), Cu(L2)(NCO)2 (7) and Cu(L2)2(N3)2(H2O)2 (8) complexes. The studies suggest the coordination of oxadiazole and coligands in all cases. Magnetic measurements show antiferromagnetic coupling for compound 5, ferromagnetic interactions for compound 2 and paramagnetic behaviour in compound 4. The susceptibility data were fitted by using the Bleaney–Bowers' equation for the copper(II) dimers derived from H = –2JS1S2. The resultant J/k values are +2.15 and –38.3 K for compounds 2 and 5, respectively. Magneto‐structural correlations are discussed and extended to more than 30 published dinuclear Cu(NN)2Cu′ diazole‐only bridged compounds. All these systems show J values close to or greater than those given by the expression J ≈ –90 + 3 Δβ (where Δβ is the difference between the Cu–N–N and Cu–N′–N′ angles). The artificial nuclease activity of 1, 2, 3 and 5 in the presence of mercaptopropionic acid or glutathione has also been analysed and compared with that exhibited by [Cu(L2)2(H2O)2](NO3)2 and CuSO4. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Synthesis of (Alkylamino)nitroarenes by Oxidative Alkylamination of Nitroarenes
Authors: Gulevskaya Anna V. , Verbeeck Stefan , Burov Oleg N. , Meyers Caroline , Korbukova Inna N. , Herrebout Wouter , Maes Bert U. W.
Published: December 2008

The viability of the oxidative alkylamination process for the derivatization of electron‐deficient carboaromatics has been investigated. 1,3‐Dinitrobenzene, 1‐nitronaphthalene, and 1,5‐ and 1,8‐dinitronaphthalenes have shown to react with a wide range of alkylamines in the presence of an oxidant (KMnO4, AgMnO4, AgPy2MnO4) to give access to the corresponding N‐alkyl‐nitroarenamines in moderate to good yields. Nitroarenes are more reactive than azines towards alkylamines.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Synthesis of Rigid π‐Conjugated Mono‐, Bis‐, Tris‐, and Tetrakis(terpyridine)s: Influence of the Degree and Pattern of Substitution on the Photophysical Properties
Authors: Winter Andreas , Friebe Christian , Hager Martin D. , Schubert Ulrich S.
Published: December 2008

A series of rigid π‐conjugated mono‐, bis‐, tris‐, and tetrakis(terpyridine)s 3–8 was synthesized in high yields by means of Horner–Wadsworth–Emmons (HWE) reactions between benzyl phosphonates 1 and an aldehyde‐functionalized terpyridine derivative 2. The photophysical properties of the materials in solution and in the solid state depend strongly both on the numbers of terpyridine moieties attached to the central phenyl cores and on the geometries of the compounds. The photophysical behavior of the ortho‐substituted compounds 5 and 8 indicated significant changes in the geometries, together with major extensions of the effective π‐conjugated systems upon excitation. Bright green emission with high quantum yields was observed for the tetrakis(terpyridine) derivative 8. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Electrochemical Chiral Sensors and Biosensors
Authors: Trojanowicz Marek , Kaniewska Marzena
Published: December 2008

Chiral molecular recognition depends on difference in stability constants of diastereomeric complexes with applied selectors, different migration of enantiomers based on the formation and dissociation of diastereomeric complexes, and on a different interaction rate of enantiomers with selector. Selected examples of electrochemical enantioselective sensors and biosensors based on different mechanisms of molecular recognition are reviewed. Chemical chiral sensors can be based on plasticized membranes incorporating a chiral ionophore, on differences of Gibbs free energy for interphase electron transfer, or on the use of molecularly imprinted polymers and electrodeposited conducting polymers doped with chiral ions. Reported chiral biosensors include enzymatic devices and immunosensors. Especially pronounced enantioselectivity of enzymatic biosensors can be employed practically, e.g., in food control, showing chiral discrimination better that two orders of magnitude. Developed, so far, chemical sensors show enantioselectivity usually not exceeding two orders magnitude and require further investigation for any practical analytical applications.
Enzyme‐Amplified Amperometric Detection of DNA Using Redox Mediating Films on Gold Microelectrodes
Authors: Hajdukiewicz Joanna , Boland Susan , Kavanagh Paul , Nowicka Anna , Stojek Zbigniew , Leech Dónal
Published: December 2008

Here we describe an amperometric assay for enzyme‐labeled detection of DNA hybridization based on a redox polymer film, cross‐linked and co‐immobilized, with a 20‐mer oligonucleotide, to pre‐adsorbed cysteamine on gold microelectrode surfaces. Hybridization between the immobilized probe DNA and a biotin‐modified target DNA (designed from the ssrA gene of Listeria monocytogenes), followed by addition of an enzyme (glucose oxidase)‐avidin conjugate and glucose, results in bioelectrocatalytic oxidation of glucose mediated by the redox polymer, generating significant amplification. The use of gold microelectrodes (25 μm, 40 μm, 100 μm diameter), coupled to careful preparation of surfaces, electronic shielding and background subtraction, results in improved analytical performance, compared to that at macroelectrodes, yielding a limit of quantification of ca. 0.6 pM, corresponding to the presence of ca. 2.5 million copies in the 7 μL assay droplet.
Lactate Dehydrogenase Biosensor Based on an Hybrid Carbon Nanotube‐Conducting Polymer Modified Electrode
Authors: Agüí L. , Eguílaz M. , Peña‐Farfal C. , Yáñez‐Sedeño P. , Pingarrón J. M.
Published: December 2008

A lactate biosensor constructed by immobilization of the enzyme lactate dehydrogenase (LDH) on a glassy carbon electrode modified with a hybrid material composed of the conducting polymer poly (3‐methylthiophene) (P3 MT), electrodeposited on the electrode surface, and multiwalled carbon nanotubes (MWCNTs), is reported. The excellent characteristics of the electrode modified with the hybrid material toward the electrochemical oxidation of NADH allowed the construction of a robust LDH electrochemical biosensor able to operate at a working potential as low as +300 mV without the need for redox mediator. Experimental variables affecting the performance of the biosensor: amount of LDH immobilized on the modified electrode surface, buffer composition and working pH value, MWCNTs loading in the hybrid material and NAD+ concentration were optimized. Under the optimized conditions, a linear calibration graph for lactate was obtained over the 1.0×10−6−5.0×10−4 M (r=0.9993) concentration range, with a detection limit of 5.6×10−7 M. The biosensor design showed good repeatability of the measurements, good reproducibility in the inter‐biosensor assays and a good selectivity against other organic acids, especially when the biosensor is coated with a Nafion film.
Measurement of Dissolved Oxygen in Biological Fluids by Using a Modified Carbon Paste Electrode
Authors: Jalali Fahimeh , Ashrafi Amir M. , Nematollahi Davood
Published: December 2008

A modified carbon paste electrode was constructed for the determination of dissolved oxygen using diamino‐o‐benzoquinone (DABQ) as the modifier. The electrochemical behavior of the electrode in citrate buffer (pH 2.0) was studied. In the presence of dissolved oxygen (DO) both cathodic and anodic peak currents decreased, indicating a chemical reaction between modifier and O2. The decrease in peak current was linearly proportional to the amount of dissolved oxygen in the concentration range of 252–1260 μM of DO. The electrode was utilized in the determination of DO in urine samples. The relative error and RSD of the method were 1.6% and 4.1%, respectively. The electrode was applied more than two months for the determination of DO without any significant divergence in its voltammetric response.
New Protocol for Determination of Rifampicine by Adsorptive Stripping Voltammetry
Authors: Tyszczuk Katarzyna , Korolczuk Mieczyslaw
Published: December 2008

For determinations of organic compounds by adsorptive stripping voltammetry till now the same material of the electrode has been used for the accumulation and stripping steps. This paper describes a new protocol for extending the range of organic compounds, which can be determined by adsorptive stripping voltammetry. In the proposed procedure the accumulation step was performed on the electrode modified by a lead film, which assures adsorption of the studied species on the modified electrode and then the stripping step of the accumulated substance was performed on the support of the lead film electrode. As an example rifampicine was accumulated by adsorption at the lead film electrode while in the stripping step lead film and then the accumulated rifampicine were oxidized at a glassy carbon electrode. Using an acetate buffer as a supporting electrolyte a calibration graph for rifampicine in the range from 2.5×10−10 to 1×10−8 mol L−1 was obtained. The detection limit for rifampicine following 60 s accumulation time was equal to 9×10−11 mol L−1. The obtained detection limit was comparable or lower than reported previously for other stripping voltammetric procedures. The proposed procedure was applied to rifampicine determination in pharmaceutical preparation.
A study on using pre‐bent steel strips as seismic energy‐dissipative devices
Authors: Wang Yen‐Po , Chien Chia‐Shang Chang
Published: December 2008

Buckling is usually conceived as an unstable structural behavior leading to lateral instability of axially loaded members, if not properly supported. However, a pre‐bent strip would become an excellent seismic energy‐dissipative device if it is deformed in a guided direction and range. Geometrically large lateral deformation of the steel strips in buckling leads to inelastic behavior of the material and dissipates energy as a consequence. The purpose of this study is to propose a new type of seismic damper in the form of braces based on pre‐bent steel strips. The nonlinear elastic stiffness of monotonously loaded pre‐bent strips in both compression and tension is derived. The energy‐dissipative characteristics of the proposed damping device are investigated via component tests under cyclic loads. Experimental results indicate that the force–displacement relationship of pre‐bent strips in cyclic loads exhibits mechanical characteristics of displacement‐dependent dampers. A series of seismic performance tests has been conducted further to verify the feasibility and effectiveness of using the proposed device as seismic dampers. Encouraging test results have been obtained, suggesting feasibility of the proposed device for earthquake‐resistant design. Copyright © 2008 John Wiley & Sons, Ltd.
FEM analysis of electromagnetic transients in nonlinear networks
Authors: Lucic Rino , Juric‐Grgic Ivica , Kurtovic Mate
Published: December 2008

The aim of the paper is to present a numerical procedure based on the finite element method (FEM) in the time domain when modeling electromagnetic transients in a single nonlinear electrical network. It presents an extension to the FE time domain model used to analyze electromagnetic transients in linear networks. Based on the Newton–Raphson method for FEM analysis and the generalized trapezoidal rule for time integration a novel numerical procedure for the computation of electromagnetic transients in nonlinear circuits/networks is obtained. Copyright © 2008 John Wiley & Sons, Ltd.
A load‐based reflection routing protocol with resource pre‐allocation for contention resolution in OBS networks
Authors: Perelló Jordi , Spadaro Salvatore , Comellas Jaume , Junyent Gabriel
Published: December 2008

We introduce and evaluate a novel reflection routing protocol to reduce burst losses in emerging optical burst switching (OBS) networks. The proposed solution selects the reflection neighbour based on current link state information. To keep pace with OBS traffic dynamics, we propose link state information to be propagated downstream in the burst control packet. As the result, accurate state information of the return links coming from each adjacent neighbour can be maintained, thus improving reflection neighbour selection. Simulation results show up to 98% improvement against classic reflection routing, also outperforming standard deflection routing (DR) especially for medium‐sized burst lengths. Copyright © 2008 John Wiley & Sons, Ltd.
Solid Polymer Electrolyte Water Electrolyser Based on Nafion‐TiO2 Composite Membrane for High Temperature Operation
Authors: Baglio V. , Ornelas R. , Matteucci F. , Martina F. , Ciccarella G. , Zama I. , Arriaga L. G. , Antonucci V. , Aricò A. S.
Published: December 2008

A composite Nafion‐TiO2 membrane was manufactured by a recast procedure, using an in‐house prepared TiO2. This membrane has shown promising properties for high temperature operation in an SPE electrolyser allowing to achieve higher performance with respect to a commercial Nafion 115 membrane. This effect is mainly due to the water retention properties of the TiO2 filler. A promising increase in electrical efficiency was recorded at low current densities for the composite membrane‐based SPE electrolyser at high temperature compared to conventional membrane‐based devices.
HPP Parbati (India) Inclined Shafts: TBM Concept, Segmental Lining and Site Experience
Authors: Gütter Wolfgang , Barwart Christian
Published: December 2008

Stage II of the 2,000 MW HPP Parbati in Himachal Pradesh, a northern district of India at the lesser Himalayan zone, will generate a total power of 800 MW. A Joint Venture of Jäger Bau GmbH (Austria) and Seli SpA (Italy) completed together with Gammon India Ltd. in December 2006 the first inclined shafts in India driven by a double shield tunnel boring machine. The two parallel 30° inclined underground pressure shafts of 1,500 m in length each have been lined by precast concrete segments simultaneously to the TBM heading. Especially the second shaft could be completed in a record of 109 working days respectively with an average daily production of almost 14 m/d! A steel lining with an inner diameter of 3.5 m is underway to be installed in the two shafts. That project might have set a milestone for the execution of inclined shafts – for sure in India but may be even in other countries as well. The paper describes the mechanical excavation of these two shafts under severe conditions in a remote area.
Amisulpride for the treatment of very‐late‐onset schizophrenia‐like psychosis
Authors: Psarros Constantin , Theleritis Christos G. , Paparrigopoulos Thomas J. , Politis Antonios M. , Papadimitriou George N.
Published: December 2008

Background

Although schizophrenia affects all age groups, late or very‐late‐onset schizophrenia‐like psychosis has not been well studied and various treatment issues remain unresolved. The objective of the present study was to evaluate the efficacy and safety of amisulpride monotherapy in a diagnostically homogeneous group of elderly patients without cognitive impairment suffering from very‐late‐onset schizophrenia.

Methods

Twenty‐six patients of mean age 76.2 ± 5.8 years, fulfilling both the recent consensus criteria for very late‐onset schizophrenia‐like psychosis and the DSM‐IV‐TR criteria for schizophrenia, were assessed by the Brief Psychiatric Rating Scale, the Clinical Global Impression Scale and the Positive and Negative Syndrome Scale at baseline and five weeks following amisulpride (50–200 mg/day) administration; also, the presence of abnormal movements was evaluated with the Simpson‐Angus Scale, the Barnes Akathisia Scale, and the Abnormal Involuntary Movement Scale.

Results

A highly significant (p < 0.001) improvement on all measures of psychotic symptomatology was observed in all patients. Amisulpride was very well tolerated by the patients and no clinically significant adverse effects were observed. Scores on all abnormal movement scales did not differ significantly prior to and after amisulpride treatment.

Conclusion

Preliminary results indicate that amisulpride appears to be an efficacious and safe atypical antipsychotic for the treatment of very‐late‐onset schizophrenia‐like psychosis. Copyright © 2008 John Wiley & Sons, Ltd.
Formation pathways of DMSO2 in the addition channel of the OH‐initiated DMS oxidation: A theoretical study
Authors: Ramírez‐Anguita Juan M. , González‐Lafont Àngels , Lluch José M.
Published: December 2008

The production of dimethyl sulfoxide (DMSO) and dimethyl sulfone (DMSO2) in the dimethyl sulfide (DMS) degradation scheme initiated by the hydroxyl (OH) radical has been shown to be very sensitive to nitrogen oxides (NOx) levels. In the present work we have explored the potential energy surfaces corresponding to several reaction pathways which yield DMSO2 from the CH3S(O)(OH)CH3 adduct [including the formation of CH3S(O)(OH)CH3 from the reaction of DMSO with OH] and the reaction channels that yield DMSO or/and DMSO2 from the CH3S(O2)(OH)CH3 adduct are also studied. The formation of the CH3S(O2)(OH)CH3 adduct from CH3S(OH)CH3 (DMS‐OH) and O2 was analyzed in our previous work. All these pathways due to the presence of NOx (NO and NO2) and also due to the reactions with O2, OH and HO2 are compared with the objective of inferring their kinetic relevance in the laboratory experiments that measure DMSO2 (and DMSO) formation yields. In particular, our theoretical results clearly show the existence of NOx‐dependent pathways leading to the formation of DMSO2, which could explain some of these experimental results in comparison with experimental measurements carried out in NOx‐free conditions. Our results indicate that the relative importance of the addition channel in the DMS oxidation process can be dependent on the NOx content of chamber experiments and of atmospheric conditions. © 2008 Wiley Periodicals, Inc. J Comput Chem, 2009
Large‐scale atmospheric circulation and global sea surface temperature associations with Horn of Africa June–September rainfall
Authors: Segele Zewdu T. , Lamb Peter J. , Leslie Lance M.
Published: December 2008

This study uses correlation, regression, and composite analyses for the period 1970–1999 to explore the relationships between the June–September rainfall in the Horn of Africa (especially Ethiopian) and large‐scale regional atmospheric circulation patterns across Africa and the Atlantic and Indian Oceans, and global sea surface temperature (SST) anomalies. Abundant rainfall in the Horn of Africa is associated with enhanced westerlies across western and central Africa. These westerlies are produced by a stronger north‐east directed mean sea level pressure (MSLP) gradient resulting from MSLP intensification over the Gulf of Guinea and deepening of the monsoon trough across the Arabian Peninsula. This is reflected by a strong correlation (−0.71) between 5‐day (pentad) Ethiopian rainfall and the Gulf of Guinea minus the Arabian Peninsula MSLP difference. This correlation decreases to − 0.39 when the seasonal cycles are removed from both time series. A wet Horn of Africa monsoon is also associated with deep moist air extending up to mid‐troposphere and large water vapour transport convergence across much of Ethiopia, a strong Somali low‐level jet, and a strong tropical easterly jet (TEJ). Although there are large changes in TEJ strength, the position of the jet axis shows little variation between wet and dry events. Associated with the TEJ, the strongest upper level divergence occurs at 100 hPa, where the raw/de‐seasonalized zonal wind speed correlates negatively (−0.71/− 0.23) with the corresponding Ethiopian rainfall at the pentad time‐scale. Furthermore, SSTs over the equatorial Pacific, Indian, and southern Atlantic Oceans correlate strongly with contemporary Ethiopian summer rainfall. In general, Ethiopian rainfall is suppressed during El Niño and enhanced during La Niña. This identification and documentation of the regional atmospheric circulation patterns and global SST anomalies directly linked to rainfall variability over Ethiopia/Horn of Africa, are crucial for developing statistical prediction schemes and designing climate model simulations for the region on intra‐seasonal to inter‐annual time‐scales. Copyright © 2008 Royal Meteorological Society
Surgical management of gastrointestinal stromal tumors: Analysis of outcome with respect to surgical margins and technique
Authors: Everett Marc , Gutman Haim
Published: December 2008

This report reviews the methods and goals of treatment of gastrointestinal stromal tumor (GIST), the most common mesenchymal tumor of the gastrointestinal tract. GISTs express CD117, which serves as an immunohistochemical diagnostic marker. Surgical excision is the definitive treatment for all primary GISTs greater than 2 cm without evidence of peritoneal seeding or metastasis. Preoperative or intraoperative biopsy is not indicated except when the differential diagnosis includes another type of malignancy. Resection may be performed by traditional open surgery or by laparoscopic or laparoscopy‐assisted procedures. Regardless of the approach, oncological precautions must be strictly observed. Tumor disruption is to be avoided at all costs; tumor enucleation leaves a tumor‐seeded pseudocapsule behind and is considered insufficient. Because GISTs rarely metastasize through the lymphatics, routine lymphadenectomy is not indicated. The importance of achieving negative microscopic margins is controversial, although patients who undergo incomplete microscopic resection may be at greater risk of locoregional recurrence. Other factors, such as tumor grade and size, may play a more significant role in predicting recurrence. Cases of advanced disease or involvement of adjacent structures should be evaluated on an individual basis by a multidisciplinary team. J. Surg. Oncol. 2008;98:588–593. © 2008 Wiley‐Liss, Inc.
Resection margins in modern rectal cancer surgery
Authors: Wasserberg Nir , Gutman Haim
Published: December 2008

At present, the preferred treatment for rectal cancer is low anterior resection with total mesorectal excision and sphincter preservation. Complete removal of the tumor's lymphatic and vascular pad with free resection margins has led to a reduction in rates of local recurrence and improved disease‐specific survival. In addition to the distal and proximal margins from the tumor edge, for an optimal outcome, it is essential to consider distal mesorectal spread and the circumferential mesorectal margin. J. Surg. Oncol. 2008;98:611–615. © 2008 Wiley‐Liss, Inc.
The effect of margins on the clinical management of ductal carcinoma in situ of the breast
Authors: Meijnen Philip , Gilhuijs Kenneth G. , Rutgers Emiel J.Th.
Published: December 2008

Complete excision is key to successful breast‐conserving treatment for patients diagnosed with ductal carcinoma in situ (DCIS). Patients with extensive DCIS should be considered the choice of mastectomy (followed by reconstruction), while for smaller DCIS breast‐conserving treatment should be performed by complete excision. This review reports on the effect of margins on the clinical management of patients with a diagnosis of DCIS. The role of preoperative imaging including MRI, surgical procedures, and pathology are described. J. Surg. Oncol. 2008;98:579–584. © 2008 Wiley‐Liss, Inc.
Facile Access to an Efficient Solid‐Supported Click Catalyst System Based on Poly(ethyleneimine)
Authors: Bonami Lies , Van Camp Wim , Van Rijckegem Dieter , Du Prez Filip E.
Published: December 2008

A novel heterogeneous copper(I) catalyst system, which is based on readily available poly(ethyleneimine), has been used as a recyclable catalyst for Cu(I) catalyzed “click” 1,3 dipolar cycloaddition reactions of azides and alkynes in organic media. Branched poly(ethyleneimine) was first methylated and then cross‐linked with 1,9‐dibromononane. Subsequently, after the immobilization of Cu(I)Br, this system was applied for heterogeneous copper catalyzed click chemistry of a few model reagents and polymeric compounds.

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