bluuebunny/crossref_metadata_2025_split huggingface dataset:
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

AbstractChemInform 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

AbstractChemInform 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

AbstractIn 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

AbstractMacrocyclic 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

AbstractThe 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

AbstractThe 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

AbstractEndohedral 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

AbstractThis 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

AbstractIntroduction: 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

AbstractGenerally, 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

AbstractPhytoremediation 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

AbstractHigh‐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

AbstractThe 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

AbstractThe 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

AbstractIn 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

AbstractThe 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

AbstractTwo 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)