bluuebunny/crossref_metadata_2025 huggingface dataset:
ChemInform Abstract: Phase Diagram of the B—B2O3 System at 5 GPa: Experimental and Theoretical Studies.
Authors: Solozhenko Vladimir L. , Kurakevych Oleksandr O. , Turkevich Vladimir Z. , Turkevich Dmitry V.
Published: August 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: High‐Pressure Synthesis and Crystal Structure of the Vanadium Orthoborate VBO3.
Authors: Haberer Almut , Huppertz Hubert
Published: August 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: Lipase‐Catalyzed Dynamic Kinetic Resolution Giving Optically Active Cyanohydrins: Use of Silica‐Supported Ammonium Hydroxide and Porous Ceramic‐Immobilized Lipase.
Authors: Sakai Takashi , Wang Kefei , Ema Tadashi
Published: August 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: One‐Pot Synthesis of Bicyclic β‐Alkoxy Amides from Cyanohydrin Ethers.
Authors: Xiao Qing , Floreancig Paul E.
Published: August 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.
Synthesis, chiral separation, and absolute configuration of bis‐(N‐aryl) atropisomeric triads: 1,2‐Bis‐[4‐methyl‐2‐(thi)oxo‐2,3‐dihydrothiazol‐3‐yl]‐benzene
Authors: Roussel Christian , Kaid‐Slimane Radia , Andreoli Federico , Renaudin Mailis , Vanthuyne Nicolas
Published: August 2008

In this work, a series of 1,2‐bis‐[4‐methyl‐2‐(thi)oxo‐2,3‐dihydrothiazol‐3‐yl]‐benzene has been prepared. These atropisomeric molecular triads were exclusively found to exist in the anti‐form. They were separated into enantiomers by liquid chromatography on a chiral support. The absolute configurations of the enantiomers were determined using a chemical correlation method together with chiral chromatography. The barriers to interconversion of the enantiomers were determined. Chirality, 2009. © 2008 Wiley‐Liss, Inc.
Chiral recognition mechanisms with macrocyclic glycopeptide selectors
Authors: Berthod Alain
Published: August 2008

Macrocyclic glycopeptide selectors are naturally occurring antibiotics produced by microorganisms. They were found to be excellent chiral selectors for a wide range of enantiomers, including amino acids. Four selectors are commercialized as chiral stationary phases (CSP) for chromatography. They are ristocetin, teicoplanin, vancomycin, and the teicoplanin aglycone (TAG). The key docking interaction for amino acid recognition was established to be a charge–charge interaction between the anionic carboxylate group of the amino acid and a cationic amine group of the macrocyclic peptidic selector basket. The carbohydrate units are responsible for secondary interactions. However, they hinder somewhat the charge–charge docking interaction. The TAG selector is more effective for amino acid enantioseparations than the other CSPs. The “sugar” units are however useful allowing for chiral recognitions of other analytes, e.g., β‐blockers, not possible with the aglycone. Thermodynamic studies established that normal phase and reversed phase enantioseparations were enthalpy‐driven. With polar waterless mobile phases used in the polar ionic mode, some separations were enthalpy‐driven and others were entropy‐driven. The linear solvation energy method was tentatively used to gain knowledge about the chiral recognition mechanism. It appeared to be a viable approach with neutral molecules but it failed with ionizable solutes. With molecular solutes and the teicoplanin CSP, the study showed a significant role of the surface charge‐induced dipole interaction and steric effects. The remarkable complementary enantioselectivity effect observed with the four CSPs is discussed. Chirality, 2009. © 2008 Wiley‐Liss, Inc.
Importance of hydrogen‐bonding sites in the chiral recognition mechanism between racemic D3 terbium(III) complexes and amino acids
Authors: Moussa Ahmed , Pham Christine , Bommireddy Shruthi , Muller Gilles
Published: August 2008

The perturbation of the racemic equilibrium of luminescent D3 terbium(III) complexes with chelidamic acid (CDA), a hydroxylated derivative of 2,6‐pyridine‐dicarboxylic acid (DPA), by added chiral biomolecules such as L‐amino acids has been studied using circularly polarized luminescence and 13C NMR spectroscopy. It is shown in this work that the chiral‐induced equilibrium shift of [Tb(CDA)3]6− by L‐amino acids (i.e. L‐proline or L‐arginine) was largely influenced by the hydrogen‐bonding networks formed between the ligand interface of racemic [Tb(CDA)3]6− and these added chiral agents. The capping of potential hydrogen‐bonding sites by acetylation in L‐proline led to a ∼100‐fold drop in the induced optical activity of the [Tb(CDA)3]6−:N‐acetyl‐L‐proline system. This result suggested that the hydrogen‐bonding networks serve as the basis for further noncovalent discriminatory interactions between racemic [Tb(CDA)3]6− and added L‐amino acids. Chirality, 2009. © 2008 Wiley‐Liss, Inc.
Enantiomer separation of imidazo‐quinazoline‐dione derivatives on quinine carbamate‐based chiral stationary phase in normal phase mode
Authors: Gyimesi‐Forrás Krisztina , Maier Norbert M. , Kökösi József , Gergely András , Lindner Wolfgang
Published: August 2008

The normal phase mode liquid chromatographic enantiomer separation capability of a quinine tert‐butyl‐carbamate‐type chiral stationary phase (CSP) has been investigated for a set of polar [1,5‐b]‐quinazoline‐1,5‐dione derivatives. This class of chiral heterocycles is currently under development as potential α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazole propionic acid (AMPA) and/or N‐methyl‐D‐aspartic acid (NMDA) receptor antagonists. The effect of the nature and concentration of polar modifier, i.e., ethanol and isopropanol, in n‐hexane‐based mobile phases, as well as the substituent pattern of the phenyl ring attached to the quinazolone framework on retention factor, enantioselectivity, and resolution was investigated. The Soczewiński competitive adsorption model was used to describe the relationship between the retention and the binary mobile phase compositions. According to this model, linear plots of the logarithms of retention factor versus molar fractions of the polar modifiers were obtained over a wide concentration range (XB between 0.15 and 0.35). Addition of equimolar ethanol yields higher resolution than isopropanol, RS values ranging between 1.54 and 2.75, whereas the latter allows to achieve moderately increased enatioselectivity. The resolution was further improved by using a ternary mixture of n‐hexane:methanol:isopropanol/85:5:10 (v/v). The most pronounced selectivity factor α and resolution RS values were obtained for the para‐hydroxy substituted compound, indicating that chiral recognition is sensitive to steric and stereoelectronic factors. In the course of optimization, the temperature‐dependence on the chiral separation was also investigated. It turned out that the enantiomer separation is predominantly enthalpically driven in normal phase mode. Chirality, 2009. © 2008 Wiley‐Liss, Inc.
New Molecular Cage Clusters of Pb by Encapsulation of Mg
Authors: Schäfer Sascha , Schäfer Rolf
Published: August 2008

Endohedral clusters formed from the Zintl ions Pb102− and Pb122− are particularly stable and therefore suitable for the assembly of larger aggregates. We therefore investigate the formation of Mg‐doped lead clusters in the gas phase, and demonstrate that a whole series of new molecular cage clusters of lead can be generated by encapsulation of magnesium. Mass spectrometry reveals that some of the cluster compounds, with one and two Mg atoms attached to the lead clusters, display large intensities compared to the pure lead clusters, which indicates that the compound clusters are particularly stable. The magnesium‐doped lead‐cluster assemblies were further analyzed within a molecular‐beam electric deflection experiment. Almost vanishing permanent dipole moments for MgPb10–16 support the idea that a single Mg atom could be encapsulated within a highly symmetric lead cage, which results in structures with not only enhanced stability but also increased symmetry compared to the pure lead clusters PbN.
Therapist technique and patient defensive functioning in ultra‐brief psychodynamic psychotherapy: a lag sequential analysis
Authors: Drapeau Martin , de Roten Yves , Beretta Véronique , Blake Emily , Koerner Annett , Despland Jean‐Nicolas
Published: August 2008

This study examined the association between therapist interventions, including interpretations, and patient defensive functioning. The first session of 32 (n = 32) Brief Psychodynamic Interventions were rated for therapist interventions and patient defensive functioning. Lag sequential analysis was used to determine if (a) there are organized sequences of therapist interventions; (b) there are predictable sequences in the patients' level of defensive functioning; (c) there are sequences of therapist interventions leading to change in the patients' defensive functioning; and (d) there are levels of patient defensive functioning leading to organized therapist response. Results suggested that there are organized sequences in the therapists' interventions and that patient in‐session defensive functioning is relatively stable. However, no chain of therapist interventions led to a predictable response in the patients' defensive functioning or vice versa. Copyright © 2008 John Wiley & Sons, Ltd.
Age differences in temperament, character and depressive mood: a cross‐sectional study
Authors: Trouillet Raphaël , Gana Kamel
Published: August 2008

Introduction: This study explores the effect of age on mean‐levels of the personality traits defined in Cloninger's personality taxonomy, and investigates the relevance of personality traits for predicting depression levels in adults aged 18 to 94 years. Method: We divided our sample (466 participants) into four age groups (young adult, adult, mature adult and elderly). Personality was measured using the Temperament and Character Inventory, and depression was assessed using the Hospital Anxiety and Depression Scale. Results: Analysis of variance showed mean‐level changes for all the personality traits except Self‐D. Post hoc analyses revealed a decrease in the level of novelty seeking with age and an increase in the level of self‐transcendence for the two oldest age groups. Reward dependence was highest among the youngest participants, whereas harm avoidance was highest for both the youngest and the oldest age groups. Depression correlated positively with harm avoidance and age but negatively with self‐transcendence. Discussion: Impulsiveness, curiosity and social dependency decrease with age, whereas spirituality increases. Young and elderly adults are more fearful and socially inhibited. Harm avoidance and self‐transcendence are the most relevant personality traits for predicting levels of depression. Copyright © 2008 John Wiley & Sons, Ltd.
Inferential confusion, obsessive beliefs and obsessive–compulsive symptoms: a multidimensional investigation of cognitive domains
Authors: Aardema Frederick , Radomsky Adam S. , O'Connor Kieron P. , Julien Dominic
Published: August 2008

Generally, research into the relationship between cognitive domains and obsessive–compulsive symptoms involves the use of scales that are highly intercorrelated with each other. The current study investigates the relationship between cognitive constructs and obsessive–compulsive symptoms using the item set of the Obsessive Beliefs Questionnaire and the Inferential Confusion Questionnaire. In order to create constructs that would not be excessively correlated with each other, factor scores were used to investigate the relationship between cognitive domains and obsessive–compulsive symptoms. Factor analysis followed by oblique rotation resulted in four moderately correlated cognitive constructs (importance/control of thoughts, inferential confusion/threat estimation, perfectionism/certainty and responsibility for preventing harm). With the exception of responsibility for preventing harm, the cognitive constructs under investigation were quite strongly related to obsessive–compulsive symptoms. In particular, hierarchical regression revealed the construct inferential confusion/threat estimation to be a global and strong predictor of obsessive–compulsive symptoms, followed by the constructs of perfectionism/certainty and the construct importance/control. Responsibility for preventing harm acted to be a negative predictor of obsessive–compulsive symptoms. It is concluded that the construct of inferential confusion acts as a more powerful predictor of obsessive–compulsive symptoms than any specific obsessive belief Copyright © 2008 John Wiley & Sons, Ltd.
Phytoremediation of Organic Contaminants in Soil and Groundwater
Authors: Reichenauer Thomas G. , Germida James J.
Published: August 2008

Phytoremediation is an emerging technology for the clean‐up of sites contaminated with hazardous chemicals. The term phytoremediation refers to a number of technologies that use photoautotrophic vascular plants for the remediation of sites contaminated with inorganic and organic contaminants. Phytoremediation of organic contaminants can be organized by considering 1) the green liver concept, which elucidates the metabolism of contaminants in planta versus that of contaminants ex planta (e.g. rhizosphere), 2) processes that lead to complete degradation (mineralization) of contaminants as opposed to those that only lead to partial degradation or transformation, and 3) active plant uptake versus passive processes (e.g. sorption). Understanding of these processes needs an interdisciplinary approach involving chemists, biologists, soil scientists, and environmentalists. This Review presents the basic concepts of phytoremediation of organic contaminants in soil and groundwater using selected contaminants as examples.
Intensity calibration and automated cell cycle gating for high‐throughput image‐based siRNA screens of mammalian cells
Authors: Poon Steven S. S. , Wong Jason T. , Saunders Darren N. , Ma Qianli C. , McKinney Steven , Fee John , Aparicio Samuel A. J. R.
Published: August 2008

High‐content microscopic screening systems are powerful tools for extracting quantitative multiparameter measures from large number of cells under numerous conditions. These systems perform well in applications that monitor the presence of objects, but lack in their ability to accurately estimate object intensities and summarize these findings due to variations in background, aberrations in illumination, and variability in staining over the image and/or sample wells. We present effective and automated methods that are applicable to analyzing intensity‐based cell cycle assays under high‐throughput screening conditions. We characterize the system aberration response from images of calibration beads and then enhance the detection and segmentation accuracy of traditional algorithms by preprocessing images for local background variations. We also provide a rapid, adaptive, cell‐cycle partitioning algorithm to characterize each sample well based on the estimated locally and globally corrected cell intensity measures of BrdU and DAPI incorporation. We demonstrated the utility and range of our cell ploidy and probe density measurement methods in a pilot screen using a siRNA library against 779 human protein kinases. With our method, multiple image‐based quantitative phenotypes can be realized from a single high‐throughput image‐based microtiter‐plate screen. © 2008 International Society for Advancement of Cytometry
Error‐aware and energy‐efficient routing approach in MANETs
Authors: Tan Liansheng , Yang Peng , Chan Sammy
Published: August 2008

The lifetime of a network is the key design factor of mobile ad hoc networks (MANETs). To prolong the lifetime of MANETs, one is forced to attain a tradeoff of minimizing the energy consumption and load balancing. In MANETs, energy waste resulting from retransmission due to high bit error rate (BER) and high frame error rate (FER) of wireless channel is significant. In this paper, we propose two novel protocols termed multi‐threshold routing protocol (MTRP) and enhanced multi‐threshold routing protocol (EMTRP). MTRP divides the total energy of a wireless node into multiple ranges. The lower bound of each range corresponds to a threshold. The protocol iterates from the highest threshold to the lowest one and chooses those routes with bottleneck energy being larger than the current threshold during each iteration. This approach thus avoids overusing certain routes and achieves load balancing. If multiple routes satisfy the threshold constraint, MTRP selects a route with the smallest hop count to further attain energy efficiency. Based on MTRP, EMTRP further takes channel condition into consideration and selects routes with better channel condition and consequently reduces the number of retransmissions and saves energy. We analyze the average loss probability (ALP) of the uniform error model and Gilbert error model and give a distributed algorithm to obtain the maximal ALP along a route. Descriptions of MTRP and EMTRP are given in pseudocode form. Simulation results demonstrate that our proposed EMTRP outperforms the representative protocol CMMBCR in terms of total energy consumption and load balancing. Copyright © 2008 John Wiley & Sons, Ltd.
Localized application of mechanical and biochemical stimuli in 3‐D culture
Authors: Petroll W. Matthew , Ma Lisha
Published: August 2008

The goal of this study was to investigate the responses of isolated cells in 3‐D culture to localized application of mechanical and biochemical signals. Corneal fibroblasts were plated inside collagen matrices for 24 hours, then imaged using time‐lapse DIC. For mechanical perturbation, a microinjection needle (Femtotip) was inserted axially into the ECM, then displaced laterally to alter local ECM stress. For biochemical stimulation, PDGF or vehicle control solution was microinjected into the matrix. Compressing the ECM perpendicular to the cell axis had no appreciable effect on cell behavior. However, pushing the ECM parallel to the cell axis induced rapid cellular contraction, followed by secondary cell spreading and tractional force generation. Injection of PDGF induced a similar cell spreading response. Cells in 3‐D matrices showed remarkable plasticity, and extension of pseudopodia could be induced at both the leading and trailing edges of migrating cells. Developmental Dynamics 237:2726–2736, 2008. © 2008 Wiley‐Liss, Inc.
Embryonic chick corneal epithelium: A model system for exploring cell–matrix interactions
Authors: Svoboda Kathy K.H. , Fischman Donald A. , Gordon Marion K.
Published: August 2008

In her initial research, Elizabeth D. Hay studied amphibian limb regeneration, but later switched her focus, and for the remainder of her career addressed the role of the extracellular matrix (ECM) in regulating embryonic morphogenesis. Much of that work used the embryonic chick corneal epithelial model. This review highlights many of the discoveries that she made using this model. Hay was the first to show that embryonic corneal epithelial cells produce fibrillar collagen. Her lab was among the first to demonstrate that corneal epithelial cells respond to a collagenous substrate by increasing ECM production, and that purified ECM molecules, added to cultures of epithelial sheets, induce a reorganization of the actin cytoskeleton. These data led to the first theories of cell–matrix interactions, illustrated in a ‘hands across the membrane’ sketch drawn by Hay. Recent work with the epithelial sheet model system has elucidated many of the signal transduction pathways required for actin reorganization in response to the ECM. In all, this body of work has amply supported Hay's belief that the embryonic corneal epithelium is a powerful model system for exploring the role of the ECM in regulating the cytoskeleton, in directing cell migration, and in profoundly influencing cell growth and differentiation during development. Developmental Dynamics 237:2667–2675, 2008. © 2008 Wiley‐Liss, Inc.
Synthesis, Structure and Reactivity of Bis(phosphido)‐Bridged Dinuclear Carbonyls of Platinum(I)
Authors: Albinati Alberto , Leoni Piero , Marchetti Fabio , Marchetti Lorella , Pasquali Marco , Rizzato Silvia
Published: August 2008

The platinum(I) dinuclear carbonyl [Pt2(μ‐PtBu2)2(PtBu2H)(CO)] (4) reacts with carbon monoxide (80 atm) to give the dicarbonyl complex [Pt(μ‐PtBu2)(CO)]2 (9), which is thermally and air stable if protected from moisture. Wet solvents convert 9 into the known trinuclear hydride Pt3(μ‐PtBu2)3(CO)2(H) (10), which is also formed by treating 9 with molecular hydrogen (180 atm). The reaction of 4 or 9 with phosphanes [PR3 = PMe3, PPh3, PCy3, PCy2H] results in the formation of the corresponding derivatives [Pt2(μ‐PtBu2)2(PtBu2H)(PR3)] [11, R = Me; 12, R = Ph; 13, R = Cy; 14, R3 = Cy2H], [Pt2(μ‐PtBu2)2(CO)(PR3)] [15, R = Me; 16, R = Ph; 17, R = Cy] or [Pt(μ‐PtBu2)(PR3)]2 [18, R = Me; 19, R = Ph; 20, R = Cy] in good yields. Complex 19 is protonated at platinum by CF3SO3H yielding the hydride [Pt2(μ‐PtBu2)2(H)(PPh3)2]CF3SO3 (21). The protonation of asymmetrically substituted 12 forms rapidly the kinetic hydride [(tBu2HP)Pt(μ‐PtBu2)2Pt(H)(PPh3)]CF3SO3 (22a), which then isomerises slowly to the more stable isomer [(Ph3P)Pt(μ‐PtBu2)2Pt(H)(PtBu2H)]CF3SO3 (22b). Dicarbonyl 9 is instead protonated at the phosphorus atom of a bridging phosphide; the unstable product of this reaction can be intercepted by adding CO to give the monophosphido‐bridged [Pt2(μ‐PtBu2)(PtBu2H)(CO)3]CF3SO3 (24) as a mixture of two isomers. The X‐ray crystal and molecular structures of 9, of a 2:1 mixture of 9 and 10, and of complexes 18, 19 and 21 are also reported.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Copper(II) Complexes of N‐Methylated Derivatives of ortho‐ and meta‐Xylyl‐Bridged Bis(1,4,7‐triazacyclononane) Ligands: Synthesis, X‐ray Structure and Reactivity as Artificial Nucleases
Authors: Belousoff Matthew J. , Graham Bim , Spiccia Leone
Published: August 2008

Two new binucleating ligands, 1,3‐bis[(4,7‐dimethyl‐1,4,7‐triazacyclononan‐1‐yl)methyl]benzene (Lmemx) and 1,2‐bis[(4,7‐dimethyl‐1,4,7‐triazacyclononan‐1‐yl)methyl]benzene(Lmeox), have been prepared from 1,4,7‐triazatricyclo[5.2.1.04,10]decane and applied in the synthesis of the corresponding copper(II) complexes, [Cu2(μ‐AcO)2(Lmemx)](ClO4)2·H2O (Cm) and [Cu2(η2‐AcO)2(Lmeox)](ClO4)2 (Co). The X‐ray crystal structures confirmed the dinuclear nature of the complexes, with pairs of copper(II) centres residing in distorted square‐pyramidal coordination environments. The nitrogen donors on the ligands occupy three facially disposed coordination sites about each copper(II) centre, with two acetate ligands completing the copper(II) coordination spheres. For Cm, both acetate groups bridge the two metal centres, whilst in Co each acetate chelates to a single metal centre. To assess their utility as simple nuclease mimics, the metal complexes were tested for their phosphate ester cleavage ability using the model phosphodiester, bis(4‐nitrophenyl)phosphate (BNPP). It was found that Co exhibited the fastest rate of BNPP hydrolysis (kobsd. = 2.4 × 10–5 s–1), this rate being five times faster than that of the CuII complex of the non‐methylated analogue. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
1,3‐Dipolar Cycloaddition Reactions Initiated with the 1,5‐Dimethyl‐3‐phenyl‐6‐oxoverdazyl Radical
Authors: Yang Angela , Kasahara Takahito , Chen Eric K. Y. , Hamer Gordon K. , Georges Michael K.
Published: August 2008

The 1,5‐dimethyl‐3‐phenyl‐6‐oxoverdazyl radical reacts at room temperature in the presence of styrene to give a dihydrotetrazinone heterocyclic structure. We surmise that the reaction occurs by a 1,3‐dipolar cycloaddition via the intermediacy of an azomethine imine. While initial reactions under nitrogen gave relatively poor yields (40 %) of the cycloaddition product, improved yields (up to 84 %) were realized when the reaction mixtures were saturated with oxygen. Acrylate, methacrylate, fumarate and maleate dipolarophiles react regioselectively and stereospecifically to provide a series of dihydrotetrazinone heterocyclic structures. These initial results demonstrate the feasibility of using verdazyl radicals as substrates for organic synthesis.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Covalent coating of hydroxyapatite by keratin stabilizes gentamicin release
Authors: Belcarz Anna , Ginalska Grażyna , Zalewska Justyna , Rzeski Wojciech , Ślósarczyk Anna , Kowalczuk Dorota , Godlewski Piotr , Niedźwiadek Justyna
Published: August 2008

A novel hybrid hydroxyapatite (HAP) matrix, covalently coated with rarely applied, hardly degradable keratin and effectively modified by gentamicin immobilized in mixed‐type mode (via interactions of diverse strength), was created. This hybrid showed a remarkably high drug immobilization yield and the most sustainable antibiotic release among all tested composites. It was also able to inhibit bacterial growth, both in surrounding liquid and on matrix surface, much longer (for at least 121 days of experiment) than analogous gelatin‐modified and nonmodified matrices. Gentamicin‐keratin‐coated‐HAP granules were nontoxic to human osteoblasts and enabled their proliferation with a rate similar as noncoated HAP. Presence of keratin on HAP granules seemed to slightly enhance the osteoblast proliferation. The results indicate that newly created HAP hybrid with covalently immobilized keratin and gentamicin—nontoxic and osteoblast‐friendly—is a promising biomaterial of significantly prolonged antibacterial activity. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Morphometric characteristics and reproductive capacity of nuclear transplants derived from embryonic cells of loach, Misgurnus anguillicaudatus
Authors: Tanaka Daisuke , Takahashi Akito , Ueno Kouichi
Published: August 2008

Nuclear transplants of loach were produced by transplantating blastula cell nuclei into nonenucleated unfertilized eggs, using recipient eggs and donor cells distinguished by different polymorphic microsatellites. Of the total of 2,847 operated eggs, 143 hatched and 119 developed to the feeding larval stage. For 15 nuclear transplants (i.e., 11.1‐year‐old fish and 4.2‐year‐old fish) that survived up to the adulthood, DNA analysis and karyotype analysis were performed. Results showed that, of the 15 fish, 14 had only a nucleus derived from the donor; moreover, 12 were diploids, 1 was a triploid, 1 was a tetraploid, and 1 was a diploid–tetraploid mosaic with both donor and recipient nuclei. For the 12 fish with only a 2n donor nucleus, morphometric analysis was performed, and two female fish and two male fish were mated with normal fish. The fish with only a 2n donor nucleus were determined to be morphometrically identical to normal fish: they had normal gametogenesis and were able to reproduce. Currently, nuclear transplantation technology is beginning to be adopted in fisheries. Biological information on nuclear transplants obtained in this study can be used in the development of nuclear transplantation technology. J. Exp. Zool. 311A:11–19, 2009. © 2008 Wiley‐Liss, Inc.
Kinetic‐energy‐sensitive mass spectrometry for separation of different ions with the same m/z value
Authors: Shiki Shigetomo , Ukibe Masahiro , Sato Yuki , Tomita Shigeo , Hayakawa Shigeo , Ohkubo Masataka
Published: August 2008

A double‐focusing mass spectrometer (MS) equipped with a superconducting‐tunnel‐junction (STJ) detector has been applied to measure relative ionization cross‐sections for the production of ions that are accompanied by different ion species with the same mass‐to‐charge (m/z) value. The STJ detector fabricated for this study enables kinetic energy (E) measurement of incoming individual ions at a counting rate of up to ∼100 k ions/s and an energy resolution (ΔE/E) of 15%. Both high counting rate and high‐energy resolution are necessary to independently determine both m and z and not the m/z value only in ion‐counting MS experiments. Ions such as 14N22+ and 14N+ with the same m/z value can be clearly discriminated using a kinetic‐energy‐sensitive MS. This fine discrimination capability allows direct determination of relative ionization cross‐sections of the homonuclear diatomic ions 14N22+/14N2+ and 16O22+/16O2+, which are difficult to measure due to the strong interference by the signals of their dissociated atomic ions with noticeably large ionization cross‐sections. The new instrument requires no low‐abundance heteronuclear diatomic molecules of the forms 14N15N or 16O17O to carry out ionization studies and thus, is expected to be useful in fields such as atmospheric science, interstellar science, or plasma physics. Copyright © 2008 John Wiley & Sons, Ltd.
How retirees work: predictors of different types of bridge employment
Authors: Gobeski Kirsten T. , Beehr Terry A.
Published: August 2008

Employment after retirement, known as bridge employment, is expected to occur more frequently because the baby boom generation will increase the number of retirees. Little is known about which employees will obtain which type of bridge employment when they retire, even though it has important implications. The present study examined work‐related attitudes, job characteristics, and work‐related accomplishments of 171 retirees in order to predict whether they would fully retire or take one of two types of bridge jobs after retirement: Career‐consistent bridge jobs or bridge jobs in fields different from their original career. Continuity theory of retirement helped predict post‐retirement employment type. Retirees who had skills specifically related to their career job were more likely to work in a career‐related bridge job than either to fully retire or to take a bridge job that was not related to their careers; retirees who formerly held career jobs with intrinsically motivating job characteristics were more likely to take a career‐related bridge job than to retire fully, and retirees who had experienced work strain in their career job were more likely to take a bridge job not related to their former career than to take a career bridge job. Copyright © 2008 John Wiley & Sons, Ltd.
Inorganic reactions of iodine(III) in acidic solutions and free energy of iodous acid formation
Authors: Schmitz Guy
Published: August 2008

An analysis of the former works devoted to the reactions of I(III) in acidic nonbuffered solutions gives new thermodynamic and kinetic information. At low iodide concentrations, the rate law of the reaction IO + I− + 2H+ ⇌ IO2H + IOH is k+B [IO][I−][H+]2 – k−B [IO2H][IOH] with k+B = 4.5 × 103 M−3s−1 and k−B = 240 M−1s−1 at 25°C and zero ionic strength. The rate law of the reaction IO2H + I− + H+ ⇌ 2IOH is k+C [IO2H][I−][H+] – k−C [IOH]2 with k+C = 1.9 × 1010 M−2s−1 and k−C = 25 M−1s−1. These values lead to a Gibbs free energy of IO2H formation of −95 kJ mol−1. The pKa of iodous acid should be about 6, leading to a Gibbs free energy of IO formation of about −61 kJ mol−1. Estimations of the four rate constants at 50°C give, respectively, 1.2 × 104 M−3s−1, 590 M−1s−1, 2 × 109 M−2s−1, and 20 M−1 s−1. Mechanisms of these reactions involving the protonation IO2H + H+ ⇌ IO2H and an explanation of the decrease of the last two rate constants when the temperature increases, are proposed. © 2008 Wiley Periodicals, Inc. Int J Chem Kinet 40: 647–652, 2008
Kinetic study of 2‐furanaldehyde, 3‐furanaldehyde, and 5‐methyl‐2‐furanaldehyde reactions initiated by Cl atoms
Authors: Cabañas B. , Tapia A. , Villanueva F. , Salgado S. , Monedero E. , Martín P.
Published: August 2008

Rate coefficients for the gas‐phase reactions of chlorine atoms with a series of furanaldehydes have been determined at 298 ± 2 K and atmospheric pressure (708.5 ± 0.1). The experiments were performed using the relative technique combined with solid‐phase microextraction (SPME) sampling and gas chromatography with flame ionization detection (GC‐FID). Rate constants were determined relative to the reaction of Cl withn‐nonane and 2‐ethylfuran. The absolute rate coefficientsk(in units of 10−10cm3molecule−1s−1) obtained were 2.61 ± 0.27 for 2‐furaldehyde, 3.15 ± 0.27 for 3‐furaldehyde, and 4 ± 0.5 for 5‐methyl‐2‐furaldehyde. This study shows that the reactions of furanaldehydes and Cl are very fast with little influence of the position of the aldehyde group or the presence of other substituent on the reactivity. The results seem to indicate a mechanism involving two main reaction channels, addition of chlorine atom to the double bond of the aromatic ring, and the abstraction of the aldehydic hydrogen. Further product studies are necessary to determine the mechanism of these reactions in more detail. © 2008 Wiley Periodicals, Inc. Int J Chem Kinet 40: 670–678, 2008
Cure kinetics FTIR study of epoxy/nickel–imidazole system
Authors: Omrani A. , Simon L. C. , Rostami A. A. , Ghaemy M.
Published: August 2008

In the first part of this work (Omrani et al., Thermochim Acta 2008, 468, 39–48), we have reported mechanism and curing behavior of diglycidyl ether of bisphenol A (DGEBA) cured with a nickel salt of imidazole. In the present study, the isothermal cure of DGEBA–Im6NiBr2 system was investigated by in situ FTIR spectroscopy. Different amounts of nickel salt were loaded into epoxy matrix to elucidate the effects of the nickel catalyst concentration on the cure kinetics and mechanism. First‐order kinetic analysis was applied to estimate the rate constants for the both steps, adduct formation and chain‐growth polymerization, in the mechanism. It has been concluded that at high nickel salts concentrations, the studied cure reaction behaves like free‐imidazole‐epoxy cure. Analysis of the activation energy showed that the second step in the mechanism is more sensitive to the level of nickel salt than the first one. Using transition state theory, the thermodynamic functions of activated complex were also estimated. © 2008 Wiley Periodicals, Inc. Int J Chem Kinet 40: 663–669, 2008
Thermal decomposition rate of N2O5 measured by cavity ring‐down spectroscopy
Authors: Ide Tomoyuki , Nakayama Tomoki , Takahashi Kenshi , Matsumi Yutaka
Published: August 2008

The thermal decomposition rate of N2O5 in 760 Torr of air as a function of temperature between 314 and 348 K has been investigated using the technique of pulsed laser cavity ring‐down spectroscopy (CRDS) detection of NO3 radicals at 662 nm. The Arrhenius expression of the thermal decomposition rates determined by the CRDS experiments, which is incorporated with literature values down to 263 K, is given by 1.36 × 1015 exp{(−11300 ± 200)/T} s−1 over the temperature range 263–348 K. © 2008 Wiley Periodicals, Inc. Int J Chem Kinet 40: 679–684, 2008
Uptake Mechanism of Oppositely Charged Fluorescent Nanoparticles in HeLa Cells
Authors: Dausend Julia , Musyanovych Anna , Dass Martin , Walther Paul , Schrezenmeier Hubert , Landfester Katharina , Mailänder Volker
Published: August 2008

The endocytotic mechanisms involved in the uptake of charged polystyrene nanoparticles into HeLa cells were investigated. Uptake experiments were done in the presence or absence of drugs known to inhibit various factors in endocytosis. Independent of the particle charge, endocytosis is highly dependent on dynamin, F‐actin, and tyrosine‐specific protein kinases, which suggests a dynamin‐dependent and lipid raft‐dependent mechanism. However, cholesterol depletion did not hinder particle uptake. Regarding positively charged particles, macropinocytosis, the microtubule network, and cyclooxygenases are also involved. The clathrin‐dependent pathway plays a minor role.

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Pseudo‐Living Anionic Telomerization of Buta‐1,3‐diene
Authors: Saito Tomonori , Harich Kim C. , Long Timothy E.
Published: August 2008

Low‐molecular‐weight liquid polybutadienes (1 000–2 000 g · mol−1) consisting of 60 mol‐% poly(buta‐1,2‐diene) repeating units were synthesized via anionic telomerization. Maintaining the initiation and reaction temperature at less than 70 °C minimized chain transfer and enabled the polymerization to occur in a living fashion, which resulted in well‐controlled molecular weights and narrow polydispersity indices. MALDI‐TOF mass spectrometry confirmed that the end groups of liquid polybutadienes synthesized via anionic telomerization contained one benzyl end and one protonated end. In comparison, the end groups of liquid polybutadienes synthesized via living anionic polymerization contained one sec‐butyl or butyl end and one protonated end.

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Microwave Promoted Polymer Analogous Amidation and Esterification of Poly(ether sulfone) Bearing Free Carboxylic Groups
Authors: Bezdushna Ella , Ritter Helmut
Published: August 2008

An effective method for modification of poly(ether sulfone) (PES) containing free carboxylic groups through amidation and esterification reactions applying a microwave technique is reported in this study. PES was synthesised by the condensation reaction of 4,4‐bis(hydroxyphenyl)‐pentanoic acid and bis(4‐chlorophenyl)sulfone. Thereupon, PES was condensed with 4‐aminobenzoic acid and 1‐naphthole under microwave irradiation and, as a comparison, under classical conditions in a pre‐heated oil bath. In contrast to the classical procedure, using microwaves, the polymer analogous amidation could be efficiently realised in apolar solvents. Incorporation of bulky aromatic groups into the polymer structure caused an increased shear rate dependent viscosity compared to the parent polymer.

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New terpenoids from Stachys parviflora Benth
Authors: Ahmad Viqar Uddin , Arshad Saima , Bader Sadia , Iqbal Shazia , Khan Afsar , Khan Saleha Suleman , Hussain Javid , Tareen Rasool Bakhsh , Ahmed Amir
Published: August 2008

Two new triterpenoidal saponins were isolated from the n‐butanolic extract of Stachys parviflora (Lamiaceae). Their structures were elucidated on the basis of spectral data as stachyssaponin A; 3β, 15α, 19α, 21β, 22α‐pentahydroxyolean‐12‐ene‐28‐oic acid 3‐O‐{α‐L‐rhamnopyranosyl‐(1 → 3)‐β‐D‐glucopyranoside}‐22‐O‐{α‐L‐arabinofuranosyl‐(1 → 3)‐β‐D‐glucopyranoside} (1) and stachyssaponin B; 2β, 3β, 15α, 21β‐tetrahydroxyolean‐12‐ene‐28‐oic acid 2‐O‐[α‐L‐arabinofuranoside]‐3, 21‐bis‐O‐[β‐D‐glucopyranoside] (2). Copyright © 2008 John Wiley & Sons, Ltd.
Pulmonary function studies in children treated by chemoradiotherapy and stem cell transplantation
Authors: Efrati Ori , Toren Amos , Duskin Hadar , Modan‐Moses Dalit , Bielorai Bella , Goldstein Gal , Churi Chaim , Vilozni Daphna
Published: August 2008

Background

Management of pediatric patients with malignant and hematological diseases is frequently associated with pulmonary complications. We assessed pulmonary function at diagnosis and during a 5‐year follow‐up to identify risk factors associated with pulmonary deterioration.

Procedure

Ninety patients (age range 3–20) who were treated at the Pediatric Hematology‐Oncology Department, Sheba Medical Center, Israel, were entered into the study. Pulmonary function testing was performed at diagnosis and at least twice during the study period.

Results

At diagnosis and thereafter values of spirometry, total lung capacity, functional residual capacity and diffusion capacity were significantly lower than predicted (P < 0.002 for all indices). The ratio between residual volume and total lung capacity (RV/TLC) was significantly higher than normal at diagnosis and throughout the study (P < 0.001). Age and treatment modalities did not show any effect on lung‐function during the study. A subgroup of seven patients (8%) developed Bronchiolitis obliterans (BO) after stem cell transplantation and development of graft versus host disease (GVHD). These patients' baseline FEF25–75 values (small airway disease) were significantly lower than FEF25–75 values of controls and other patients while all other parameters were similar. The RV/TLC in the BO patients gradually increased relative to other patients during the 5‐year follow‐up.

Conclusion

Lung‐function in pediatric hemato‐oncological patients at diagnosis is lower than predicted. Abnormal baseline FEF25–75 may be a risk factor for the development of BO in the setting of GVHD after treatment. Careful monitoring, especially of FEF25–75 and RV/TLC at baseline and in the first period after diagnosis. Pediatr Blood Cancer 2008;51:684–688. © 2008 Wiley‐Liss, Inc.
Oligopeptide‐based amide functional initiators for ATRP
Authors: Adams Dave J. , Young Iain
Published: August 2008

Polymer–peptide conjugates are receiving significant interest. Here, we show that, under the appropriate conditions, a small family of oligopeptide‐based initiators can be used successfully to initiate the polymerization of methacrylic monomers by atom transfer radical polymerization (ATRP), generating new examples of such materials. However, the use of the peptidic amide‐based initiators results in polymers which have a higher molecular weight than expected and a significantly higher polydispersity than those prepared from ester‐based initiators. In many cases significant initiator remains, suggesting that either not all peptides successfully initiate polymerization or that significant termination reactions occur early in the reaction. This low initiator efficiency agrees with other reports for amino acid‐based initiators. It therefore appears that such amide‐based initiators can be used successfully, but have a significantly lower applicability than the more commonly used ester‐based initiators. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 6082–6090, 2008
Living cationic polymerization of amide‐functional vinyl ethers: Specific properties of SnCl4‐based initiating system
Authors: Yonezumi Motomasa , Okumoto Satoshi , Kanaoka Shokyoku , Aoshima Sadahito
Published: August 2008

Living cationic copolymerization of amide‐functional vinyl ethers with isobutyl vinyl ether (IBVE) was achieved using SnCl4 in the presence of ethyl acetate at 0 °C: the number–average molecular weight of the obtained polymers increased in direct proportion to the monomer conversion with relatively low polydispersity, and the amide‐functional monomer units were introduced almost quantitatively. To optimize the reaction conditions, cationic polymerization of IBVE in the presence of amide compounds, as a model reaction, was also examined using various Lewis acids in dichloromethane. The combination of SnCl4 and ethyl acetate induced living cationic polymerization of IBVE at 0 °C when an amide compound, whose nitrogen is adjacent to a phenyl group, was used. The versatile performance of SnCl4 especially for achieving living cationic polymerization of various polar functional monomers was demonstrated in this study as well as in our previous studies. Thus, the specific properties of the SnCl4 initiating system are discussed by comparing with the EtxAlCl3−x systems from viewpoints of hard and soft acids and bases principle and computational chemistry. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 6129–6141, 2008
Synthesis and characterization of double thermo‐responsive block copolymer consisting N‐isopropylacrylamide by atom transfer radical polymerization
Authors: Kotsuchibashi Youhei , Kuboshima Yumi , Yamamoto Kazuya , Aoyagi Takao
Published: August 2008

In this thesis, we studied the convenient synthesis and characterizations of thermo‐responsive materials with double response. To achieve these, AB‐type diblock copolymers comprising of poly(N‐isopropylacrylamide) (NIPAAm) segment and poly(NIPAAm‐co‐(N‐(hydroxymethyl)acrylamide) (HMAAm)) one were designed. That was synthesized in one‐pot using an atom transfer radical polymerization (ATRP) technique. Poly(NIPAAm‐co‐HMAAm)s synthesized separately showed sensitive thermo‐response and the cloud point was completely tunable by the composition of HMAAm. As expected, the block copolymers exhibited double thermo‐responsive profiles in aqueous solution. The responsive behavior was discussed by precise trace by 1H NMR and turbidity measurements. From these results, we could confirm almost independent dehydration of each segment. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 6142–6150, 2008
Preparation and characterization of porous polymeric microspheres obtained from multifunctional methacrylate monomers
Authors: Grochowicz Marta , Bartnicki Andrzej , Gawdzik Barbara
Published: August 2008

Synthesis and properties of the new difunctional methacrylate monomer 2‐hydroxy‐3‐methacryloyloxypropoxybenzene are presented. This monomer was applied for the synthesis of porous microspheres. It was copolymerized with trimethylolpropane trimethacrylate in the presence of two pairs of pore‐forming diluents dodecane and toluene, and n‐decanol and toluene. Influence of diluents composition on their porous structures was studied. Thermal resistance and tendency to swell in different organic diluents for a chosen sample were also determined. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 6165–6174, 2008
A novel dispersant for preparation of high loading and photosensitive carbon black dispersion
Authors: Kuo Kuo‐Huai , Peng Yu‐Hsiang , Chiu Wen‐Yen , Don Trong‐Ming
Published: August 2008

High loading of stable carbon black (CB) dispersion in organic solvent, PGMEA, was prepared by a ball‐milling process when using poly(styrene‐EHA‐HEMA)‐block‐poly(styrene‐EHA‐HEMA‐DMAEMA) (P(SEH)‐b‐P(SEHD)) as a dispersant. The P(SEH)‐b‐P(SEHD) containing P(SEH) as a steric chain and P(SEHD) as an anchoring chain was prepared by TEMPO‐mediated polymerization. The tertiary amine group of DMAEMA in P(SEHD) chain could be adsorbed onto CB by the interaction with the carboxylic acid group on surface of CB and the P(SEH) chain could provide sufficiently steric repulsion force to avoid the aggregation of CB. In addition, a photosensitive dispersant, P(SEH)‐b‐P(SEHD)CC, containing the methacrylate double bond side group was also synthesized and was used to prepare stable CB dispersion in PGMEA. The effects of the molecular weight between steric and anchoring chains, the content of tertiary amine, and the amount of methacrylate double bond in the dispersant on the particle size of CB were investigated. Furthermore, the influences of various surface properties of CB, such as specific surface area, content of carboxylic acid group, and size of primary particle, on the particle size of CB in dispersion were also discussed. Finally, the photosensitivity of P(SEH)‐b‐P(SEHD)CC/CB composite was monitored by a photodifferential scanning calorimeter. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 6185–6197, 2008