bluuebunny/crossref_metadata_2025 huggingface dataset:
Morphological assessment of the behavior of three‐dimensional anionic collagen matrices in bone regeneration in rats
Authors: Miguel Fúlvio B. , Cardoso Ana Karina M. V. , Barbosa Aryon A. , Marcantonio Elcio , Goissis Gilberto , Rosa Fabiana P.
Published: February 2006

The osteogenic behavior of three‐dimensional collagenic and anionic matrices (M3DGA) implanted in critical bone defects of 8 mm diameter was morphologically assessed. The defects were performed in the calvaria of 48 adult male (Wistar) rats, and observed at days 15, 30, and 60. The animals were distributed in four groups of equal number: GA1 (M3DGA with 60 min of cross‐linking in glutaraldehyde [GA]); GA2 (M3DGA with 30 min of cross‐linking in GA); GA3 (M3DGA with 15 min of cross‐linking in GA); and G4 (control group, without any implanted biomaterial). The M3DGAs were biocompatible, with mild and regressive chronic granulomatous inflammation, associated with the degradation of their fibers. Furthermore, tissue neovascularization and neomineralization was noted, with statistically significant differences in these amounts among the groups (GA1, GA2, and GA3) and G4. In G4 neoformation was limited to the edges of the defect as well as interstitial fibrosis. Under the experimental conditions and for the parameters analyzed, the M3DGAs had osteogenic behavior, which was more evident in M3DGA 15 min. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Effect of pH and temperature on orthodontic NiTi wires immersed in acidic fluoride solution
Authors: Ahn Hyung‐Soo , Kim Myong‐Jin , Seol Hyo‐Joung , Lee Jung‐Hyun , Kim Hyung‐Il , Kwon Yong Hoon
Published: February 2006

Orthodontic arch wires can confront diverse pH and temperature conditions in the oral cavity after replacement. The current study evaluated the effect of pH and temperature on orthodontic NiTi arch wires after immersion in an acidic fluoride solution. The acetic acid added for the adjustment of pH forms hydrofluoric acid (HF). More HF was formed in a solution of lower pH with higher temperature than that of the higher pH with lower temperature. Within the same pH value, the temperature of the solution affected the concentration of HF. Each as‐received wire exhibited quite different microhardness values. The reduction of microhardness, 1.2–5.7%, occurred after immersion. Within the same product, however, the pH and temperature had minor influence on the reduction. The volumetric weight change, concentration of the released elements, and surface morphology were influenced by pH and temperature. At pH 3.5 of 60°C solution, the greatest weight loss, release of elements, and corrosion of surface occurred from the wires. At pH 6, on the other hand, no such loss or release occurred regardless of temperature. At 5°C solution, the surface exhibited minor corrosion regardless of pH value. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
The effect of fiber insertion on fracture resistance of endodontically treated molars with MOD cavity and reattached fractured lingual cusps
Authors: Belli Sema , Cobankara Funda Kont , Eraslan Oğuz , Eskitascioglu Gürcan , Karbhari Vistasp
Published: February 2006

In this study, the effect of flowable composite reinforced with a leno wave ultra high modulus (LWUHM) polyethylene fiber (Ribbond) on fracture resistance of endodontically treated molars with MOD cavity and lingual cuspal fracture was evaluated. Sixty sound extracted human mandibular molars were randomly assigned to six groups (n = 10). Group 1 served as control. Teeth in groups 2–6 received root canal treatment and a MOD cavity preparation. Teeth in group 2 were kept unrestored. Lingual walls of specimens in groups 3–6 were fractured at the CEJ and reattached (C&B Super‐Bond). Group 3 was kept unrestored, and group 4 was restored with a composite resin (CR) (AP‐X). In group 5, a flowable resin (FR, Protect Liner F) and in group 6, a Ribbond in combination with FR were inserted inside the cavity before CR restoration. After finishing and polishing, the specimens were subjected to compressive loading perpendicular to the occlusal surface at a crosshead speed of 1 mm/min. The mean load necessary to fracture were recorded in Newton and the results were statistically analyzed. MOD cavity preparation reduced fracture resistance of endodontically treated teeth (p < 0.05). Fracture resistance of rebonded fractured specimens was found to be similar to that of the nonfractured samples (p > 0.05). Use of LWUHM polyethylene fiber Ribbond increased fracture strength of endodontically treated molar teeth with MOD cavity preparation and cuspal fracture (p < 0.05). As a result, it was concluded that the insertion of Ribbond inside the cavity has a positive effect on fracture strength of endodontically treated molar teeth with MOD cavity preparation and cuspal fracture. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Transverse fracture of brittle bilayers: Relevance to failure of all‐ceramic dental crowns
Authors: Kim Jae‐Won , Bhowmick Sanjit , Hermann Ilja , Lawn Brian R.
Published: February 2006

This study examines the behavior of cracks approaching interfaces in all‐ceramic dental crown‐like bilayers. Flat specimens are fabricated by fusing porcelain veneers onto yttria‐tetragonal‐zirconia‐polycrystal (Y‐TZP) and alumina core ceramic plates, with veneer/core matching to minimize residual thermal expansion mismatch stresses. Vickers indentations are placed on either side of the interfaces, at systematically decreasing distances, so that the lead corner cracks approach and intersect the interfaces in a normal orientation. Cracks originating in the porcelain arrest at the boundaries and, after further diminution in indentation distance, deflect along the interface without penetration into the tough core ceramic. Cracks initiating in the core ceramic pass unimpeded into the weaker porcelain without deflection, and with abrupt increase in crack size. These latter cracks, because of their lack of containment within the core layer, are regarded as especially dangerous. Implications concerning the design of optimal dental crowns in relation to materials optimization are considered. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
The internalized CdSe/ZnS quantum dots impair the chondrogenesis of bone marrow mesenchymal stem cells
Authors: Hsieh Shu‐Chen , Wang Fung‐Fang , Hung Shih‐Chieh , Chen Yu‐Ju , Wang Yng‐Jiin
Published: February 2006

Mesenchymal stem cells (MSCs) are capable of differentiating into multiple cell lineages and are useful for therapeutic applications. Labeling the MSCs with fluorescent probes is beneficial in tracing the fate of MSCs after implantation. We have introduced the CdSe/ZnS quantum dots (QDs) into the human bone marrow MSCs and examined the effects of QDs on the proliferation and chondrogenesis of the cells. The internalized QDs were found localized in perinuclear regions and remained there after a number of cell passages. The presence of QDs did not affect the proliferation of cells or the size of chondrospheres formed, when subjected to chondrogenesis induction. However, the expression of mRNA and protein of type II collagen and aggrecan in the chondrospheres was significantly inhibited in cells labeled with QDs, suggesting impaired chondrogenesis. Our results that the presence of QDs interferes with the chondrogenic differentiation of MSCs raise concerns in using the QDs as fluorescence tracers for stem cells. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Leptin effect on RANKL and OPG expression in MC3T3‐E1 osteoblasts
Authors: Lamghari M. , Tavares L. , Camboa N. , Barbosa M.A.
Published: February 2006

Recent studies have suggested that leptin hormone may play a pivotal role on bone remodeling through a direct effect by modulating positively the OPG/RANKL balance. Here, we investigate the effect of leptin hormone on RANKL and OPG expression in MC3T3‐E1 osteoblasts using RT‐PCR and ELISA measurements. We have at first identified the expression of Ob‐Rb and Ob‐Ra leptin receptor isoforms in MC3T3‐E1 and observed that these cells respond to mrleptin treatments. We then investigated the effect of mrleptin on RANKL and OPG expression. We show that mrleptin dose‐dependently regulated the expression of RANKL mRNA with complete inhibition observed at concentrations higher than 12 ng/ml. This effect was confirmed with sRANKL protein measurements. However, the exposure of MC3T3‐E1 to mrleptin had no effect on OPG mRNA. Taken together, these results suggest that leptin modulates positively OPG/RANKL balance by inhibiting the expression of RANKL gene. J. Cell. Biochem. 98: 1123–1129, 2006. © 2006 Wiley‐Liss, Inc.
Monosilicon‐substituted cyanoacetylene: A computational study
Authors: Yang Li‐Ming , Ding Yi‐Hong , Wang Qiang , Sun Chia‐Chung
Published: February 2006

A detailed theoretical investigation of the [H,Si,C2,N] potential energy surfaces including 28 minimum isomers and 65 interconversion transition states is reported at the Gaussian‐3//B3LYP/6‐31G(d) level. Generally, the triplet species lie energetically higher than the singlet ones. The former three low‐lying isomers are linear HCCNSi 1 (0.00 kcal/mol), branched SiC(H)CN 12 (7.09 kcal/mol), and bent HNCCSi 7 (14.22 kcal/mol), which are separated by rather high barriers from each other and are kinetically very stable with the least conversion barriers of 32.6–70.5 kcal/mol. Two energetically high‐lying isomers HCNCSi 3 (42.99 kcal/mol) and SiC(H)NC 13 (36.05 kcal/mol) are also kinetically stable with a barrier of 49.19 and 21.42 kcal/mol, respectively. Additionally, five high‐lying isomers, that is, three chainlike isomers, HCCSiN 2 (55.17), HCSiNC 6 (47.80), HSiNCC 11 (78.83), and one three‐membered ring isomer HNcSiCC 19 (51.21), and one four‐membered ring isomer cSiCN(H)C 27 (50.6 kcal/mol), are predicted to each have lower conversion barriers of 12–18 kcal/mol and can be considered as meta‐stable species. All of the predicted 10 isomers could exist as stable or meta‐stable intermediates under suitable conditions. Finally, the structural and bonding analysis indicate that the [H,Si,C2,N] molecule contains various properties that are of chemical interest (e.g., silylene, SiC triple bonding, and conjugate SiN triple bonding and CC triple bonding, charge–transfer specie, planar aromatic specie, cumulate double bonding). This is the first detailed theoretical study on the potential energy surfaces of the series of hydrogenated Si,C,C,N‐containing molecules. The knowledge of the present monohydrogenated SiC2N isomerism could provide useful information for more highly hydrogenated or larger Si,C2,N‐containing species. © 2006 Wiley Periodicals, Inc. J Comput Chem 27: 578–595, 2006
A consensus procedure improving solvent accessibility prediction
Authors: Gianese Giulio , Pascarella Stefano
Published: February 2006

Prediction methods of structural features in 1D represent a useful tool for the understanding of folding, classification, and function of proteins, and, in particular, for 3D structure prediction. Among the structural aspects characterizing a protein, solvent accessibility has received great attention in recent years. The available methods proposed for predicting accessibility have never considered the combination of the results deriving from different methods to construct a consensus prediction able to provide more reliable results. A consensus approach that increases prediction accuracy using three high‐performance methods is described. The results of our method for three different protein data sets show that up to 3.0% improvement in prediction accuracy of solvent accessibility may be obtained by a consensus approach. The improvement also extends to the correlation coefficient. Application of our consensus approach to the accessibility prediction using only three prediction methods gives results better than single methods combined for consensus formation. Currently, the scarce availability of predictors with similar parameters defining solvent accessibility hinders the testing of other methods in our consensus procedure. © 2006 Wiley Periodicals, Inc. J Comput Chem 27: 621–626, 2006
Singular value decomposition of torsional angles of analogs of the dopamine reuptake inhibitor GBR 12909
Authors: Fiorentino Anna , Pandit Deepangi , Gilbert Kathleen M. , Misra Milind , Dios Rose , Venanzi Carol A.
Published: February 2006

Analysis of large, flexible molecules, such as the dopamine reuptake inhibitor GBR 12909 (1), is complicated by the fact that they can take on a wide range of closely related conformations. The first step in the analysis is to classify the conformers into groups. Here, Singular Value Decomposition (SVD) was used to group conformations of GBR 12909 analogs by the similarity of their nonring torsional angles. The significance of the present work, the first application of SVD to the analysis of very flexible molecules, lies in the development of a novel scaling technique for circular data and in the grouping of molecular conformations using a technique that is independent of molecular alignment. Over 700 conformers each of a piperazine (2) and piperidine (3) analog of 1 were studied. Analysis of the score and loading plots showed that the conformers of 2 separate into three large groups due to torsional angles on the naphthalene side of the molecule, whereas those of 3 separate into nine groups due to torsional angles on the bisphenyl side of the molecule. These differences are due to nitrogen inversion at the unprotonated piperazinyl nitrogen of 2, which results in a different ensemble of conformers than those of 3, where no inversion is possible at the corresponding piperidinyl carbon. © 2006 Wiley Periodicals, Inc. J Comput Chem 27: 609–620, 2006
The VMFCI method: A flexible tool for solving the molecular vibration problem
Authors: Cassam‐Chenaï P. , Liévin J.
Published: February 2006

The present article introduces a general variational scheme to find approximate solutions of the spectral problem for the molecular vibration Hamiltonian. It is called the “vibrational mean field configuration interaction” (VMFCI) method, and consists in performing vibrational configuration interactions (VCI) for selected modes in the mean field of the others. The same partition of modes can be iterated until self‐consistency, generalizing the vibrational self‐consistent field (VSCF) method. As in contracted‐mode methods, a hierarchy of partitions can be built to ultimately contract all the modes together. So, the VMFCI method extends the traditional variational approaches and can be included in existing vibrational codes based on the latter approaches. The flexibility and efficiency of this new method are demonstrated on several molecules of atmospheric interest. © 2006 Wiley Periodicals, Inc. J Comput Chem 27: 627–640, 2006
Psychotherapy for patients with borderline personality disorder: Focusing on the mechanisms of change
Authors: Clarkin John F. , Levy Kenneth N.
Published: February 2006

A major development in the field of psychotherapy research is the growing recognition of the need for evidence on the mechanisms of change in psychotherapy. The empirical evidence that psychotherapy has a positive and significant effect must be amplified with data on the mechanisms of action in the various psychotherapies. This special issue is devoted to the articulation of putative mechanisms of change in the psychotherapy of patients with borderline personality disorder by leading researchers in this field. © 2006 Wiley Periodicals, Inc. J Clin Psychol 62: 405–410, 2006.
Schema therapy for borderline personality disorder
Authors: Kellogg Scott H. , Young Jeffrey E.
Published: February 2006

This article presents the Schema Therapy (Young, Klosko, & Weishaar, 2003) approach to the treatment of borderline personality disorder. Schema therapy draws on the cognitive‐behavioral, attachment, psychodynamic, and emotion‐focused traditions and conceptualizes patients who have borderline personality disorder as being under the sway of five modes or aspects of the self. The goal of the therapy is to reorganize this inner structure. To this end, there are four core mechanisms of change that are used in this therapy: (1) limited reparenting, (2) experiential imagery and dialogue work, (3) cognitive restructuring and education, and (4) behavioral pattern breaking. These interventions are used during the three phases of treatment: (1) bonding and emotional regulation, (2) schema mode change, and (3) development of autonomy. © 2006 Wiley Periodicals, Inc. J Clin Psychol 62: 445–458, 2006.
Mechanisms of change in mentalization‐based treatment of BPD
Authors: Fonagy Peter , Bateman Anthony W.
Published: February 2006

There are very few less contentious issues than the role of attachment in psychotherapy. Concepts such as the therapeutic alliance speak directly to the importance of activating the attachment system, normally in relation to the therapist in individual therapy and in relation to other family members in family‐based intervention, if therapeutic progress is to be made. In group therapy the attachment process may be activated by group membership. The past decade of neuroscientific research has helped us to understand some key processes that attachment entails at brain level. The article outlines this progress and links it to recent findings on the relationship between the neural systems underpinning attachment and other processes such as making of social judgments, theory of mind, and access to long‐term memory. These findings allow intriguing speculations, which are currently undergoing empirical tests on the neural basis of individual differences in attachment as well as the nature of psychological disturbances associated with profound disturbances of the attachment system. In this article, we explore the crucial paradoxical brain state created by psychotherapy with powerful clinical implications for the maximization of therapeutic benefit from the talking cure. © 2006 Wiley Periodicals, Inc. J Clin Psychol 62: 411–430, 2006.
Mechanisms of change in dialectical behavior therapy: Theoretical and empirical observations
Authors: Lynch Thomas R. , Chapman Alexander L. , Rosenthal M. Zachary , Kuo Janice R. , Linehan Marsha M.
Published: February 2006

Dialectical behavior therapy (DBT) can be considered a well‐established treatment for borderline personality disorder (BPD) as evidenced by seven well‐controlled randomized clinical trials across four independent research teams. The primary purpose of this article is to address a variety of potential mechanisms of change that may be associated with those aspects of DBT that are unique to the treatment and its theoretical underpinnings. Based on the biosocial theory of BPD, many of these mechanisms can be distilled down to the following process:the reduction of ineffective action tendencies linked with dysregulated emotions. Specifically we address the following interventions and associated mechanisms of change: mindfulness, validation, targeting and chain analysis, and dialectics. Patient change in BPD is conceptualized primarily as helping the patient to engage in functional, life‐enhancing behavior, even when intense emotions are present. Ultimately, our goal was to provide guidance for theoretically and empirically grounded research on the mechanisms of change in DBT. © 2006 Wiley Periodicals, Inc. J Clin Psychol 62: 459–480, 2006.
Hypothesized mechanisms of change in cognitive therapy for borderline personality disorder
Authors: Wenzel Amy , Chapman Jason E. , Newman Cory F. , Beck Aaron T. , Brown Gregory K.
Published: February 2006

Preliminary evidence suggests that cognitive therapy (CT) is effective in treating borderline personality disorder (BPD). According to cognitive theory, BPD patients are characterized by dysfunctional beliefs that are relatively enduring and inflexible and that lead to cognitive distortions such as dichotomous thinking. When these beliefs are activated, they lead to extreme emotional and behavioral reactions, which provide additional confirmation for the beliefs. It is hypothesized that a change in dysfunctional beliefs is the primary mechanism of change associated with CT. However, additional mechanisms of change are likely also at work in CT, including enhancement of skills, reduction in hopelessness, and improvement in attitude toward treatment. Each of these mechanisms is discussed in light of cognitive theory, data from an open clinical CT trial, relevant literature, and therapeutic interventions. Findings from the CT trial support the role of cognitive change during therapy and its continuation after termination. © 2006 Wiley Periodicals, Inc. J Clin Psychol 62: 503–516, 2006.
Attenuation of mouse acute colitis by naked hepatocyte growth factor gene transfer into the liver
Authors: Hanawa Takayasu , Suzuki Kenji , Kawauchi Yusuke , Takamura Masaaki , Yoneyama Hiroyuki , Han Gi Dong , Kawachi Hiroshi , Shimizu Fujio , Asakura Hitoshi , Miyazaki Jun‐ichi , Maruyama Hiroki , Aoyagi Yutaka
Published: February 2006

Background

Hepatocyte growth factor (HGF) has multiple biological effects on a wide variety of cells. It modulates intestinal epithelial proliferation and migration, and critically regulates intestinal wound healing.

Aims

To investigate the therapeutic effect of HGF gene transfer, we introduced the HGF gene into the liver of mice with acute colitis.

Methods

The rat HGF expression plasmid vector, pCAGGS‐HGF, was injected via the tail vein into C57BL/6 mice, followed by dosing with dextran sulfate sodium in distilled water. Firstly, the HGF gene was injected once on day 0. Secondly, the HGF gene was injected on day 0 and again on day 2.

Results

Injection of the HGF gene ameliorated colitis with inhibition of both loss of body weight and shortening of colon length. It protected the colon from epithelial erosions and cellular infiltration. Expression of mRNAs for IFN‐γ, IL18, and TNF‐α was reduced in the colon. In contrast, expression of mRNA for IL‐10 was increased. The numbers of BrdU‐positive intestinal epithelial cells were increased, and the numbers of TUNEL‐positive apoptotic cells were decreased. Furthermore, a second injection prolonged the elevation of serum HGF levels, and ameliorated the symptoms better than a single injection. The empty pCAGGS plasmid did not ameliorate acute colitis.

Conclusions

HGF gene transfer attenuated acute colitis by facilitating intestinal wound repair as well as inhibiting inflammation, suggesting a new strategy for treatment of IBD. Copyright © 2006 John Wiley & Sons, Ltd.
Fragmentation study of imatinib and characterization of new imatinib metabolites by liquid chromatography–triple‐quadrupole and linear ion trap mass spectrometers
Authors: Marull Marc , Rochat Bertrand
Published: February 2006

Imatinib (Gleevec) is an anticancer drug that inhibits specific protein kinases involved in cell proliferation. Whereas this drug is considered to have opened a new era, various mechanisms of resistance have been associated with imatinib relapse. Drug disposition in cancer cells including influx, efflux and drug metabolism is one mechanism that remains to be more thoroughly investigated. Moreover, recent genomic studies have revealed that some isozymes of cytochrome P450 (CYP) are possibly associated with the treatment outcome. Therefore, this research paper investigates the role of the activity of CYP1A1, 1A2, 1B1, 3A4, 4F2 and 4F3A/B on the fate of imatinib.

First, a study of imatinib fragmentation was effected using electrospray triple‐quadrupole and linear ion trap tandem mass spectrometers (MSn). Accurate mass determinations were performed at enhanced mass resolution for the identification of some product ions that were not predicted by two fragmentation softwares. Whereas the quadrupole MS was not designed for accurate mass measurement, delta mass errors were below 20 ppm.

Then, a biotransformation study was effectedin vitro. Imatinib metabolites were produced in microsomal incubations containing CYP isozymes. Imatinib and metabolites were extracted from incubation mixtures by protein precipitation, and supernatants were injected into a liquid chromatography equipment coupled with MSn. Hydrophobic interaction liquid chromatography resolved one demethylated‐, two hydroxy‐ and three N‐oxide metabolites. Various rates of metabolite formation were observed between CYP isozymes.

Liquid chromatography with deuterium oxide–containing mobile phase (H/D exchange) or incorporation of18O from H218O added in the incubations was performed to elucidate the metabolite structure. Various MSnproduct scans (n⩽ 4) were acquired on the linear ion trap or on the triple‐quadrupole MS. Postulated structures of new metabolites are addressed. Copyright © 2006 John Wiley & Sons, Ltd.
Study of transaldolase deficiency in urine samples by capillary LC‐MS/MS
Authors: Vas György , Conkrite Karina , Amidon Wendy , Qian Yueming , Bánki Katalin , Perl András
Published: February 2006

Transaldolase (TAL) is a key enzyme of the pentose phosphate pathway (PPP). TAL deficiency is a newly recognized cause of liver cirrhosis. We have developed an ion‐pair LC separation combined with negative ion electrospray MS/MS detection method to assess PPP metabolites in urine samples from TAL‐deficient mice. Sedoheptulose 7‐phosphate (S7P), C5‐polyols D‐arabitol and D‐ribitol, and 6‐phosphogluconate (6PG) levels were markedly increased in urine of TAL‐deficient mice with respect to those of wild‐type and heterozygote littermates. The detection limits of S7P, D‐arabitol, and 6PG were 0.15 ± 0.015 pmol, 3.5 ± 0.41 pmol, and 0.61 ± 0.055 pmol, respectively. The limit of quantitation was 0.4 ± 0.024 nmol/ml for S7P, 1.6 ± 0.11 nmol/ml for 6PG and 10 ± 0.7 nmol/ml for D‐arabitol. Additional metabolites, hexose 6‐phosphates (m/z 259), D‐ribose 5‐phosphate and D‐xylulose 5‐phosphate (m/z 229), D‐fructose 1,6‐diphosphate (m/z 339), C6‐polyols (m/z 181) and GSSG (m/z 611), that have been positively identified in mouse urine, showed similar levels in control and TAL‐deficient mice. Copyright © 2006 John Wiley & Sons, Ltd.
Designer drugs 2,5‐dimethoxy‐4‐bromo‐amphetamine (DOB) and 2,5‐dimethoxy‐4‐bromo‐methamphetamine (MDOB): studies on their metabolism and toxicological detection in rat urine using gas chromatographic/mass spectrometric techniques
Authors: Ewald Andreas H. , Fritschi Giselher , Bork Wolf‐Rainer , Maurer Hans H.
Published: February 2006

Studies are described on the metabolism and the toxicological analysis of the amphetamine‐derived designer drug 2,5‐dimethoxy‐4‐bromo‐amphetamine (DOB) and its corresponding N‐methyl analogue 2,5‐dimethoxy‐4‐bromo‐methamphetamine (MDOB) in rat urine using gas chromatographic/mass spectrometric techniques. The identified metabolites indicated that DOB was metabolized by O‐demethylation followed by oxidative deamination to the corresponding ketone as well as deamination followed by reduction to the corresponding alcohol. Other metabolic pathways were O,O‐bisdemethylation or hydroxylation of the side chain followed by O‐demethylation and deamination to the corresponding alcohol. The expected oxo compound after deamination could not be detected. All metabolites carrying hydroxy groups were found to be partly excreted in the conjugated form. MDOB underwent O‐demethylation, O,O‐bisdemethylation, or hydroxylation of the side chain followed by O‐demethylation. Additional N‐demethylation to DOB occurred, including the above‐mentioned metabolites. Again, all metabolites carrying hydroxy groups were found to be partly excreted in the conjugated form. The authors' systematic toxicological analysis (STA) procedure using full‐scan GC/MS after acid hydrolysis, liquid–liquid extraction, and microwave‐assisted acetylation allowed the detection of an intake of a dose of DOB and MDOB in rat urine that corresponds to a common drug user's dose. Assuming a similar metabolism, the described STA procedure in human urine should be suitable as proof of an intake of DOB and MDOB. Copyright © 2006 John Wiley & Sons, Ltd.
Alcoa's Michigan Casting Center runs the business from the bottom up
Authors: Groszkiewicz Dan , Warren Brent
Published: February 2006

A manufacturing facility set out to tackle serious production problems and workforce instability. With each level of improvement came an even deeper understanding of other problems and opportunities. Now, five years later, a new operating philosophy, organizational structure, flow of processes, and set of tools enable the hourly associates to run the plant and managers to focus on more strategic issues—and a once‐troubled business is now healthy and competitive. © 2006 Wiley Periodicals, Inc.
Factiva reshapes marketing for better lead generation
Authors: Scott Alan
Published: February 2006

In the fast‐changing arena of on‐line news and business information search and retrieval, markets do not stand still. And neither could the marketing function of three‐year‐old Factiva. The marketing organization leveraged new leadership, market intelligence, technology, decision‐making tools, and a new mind set of collaboration to achieve a top‐to‐bottom, inside‐out transformation. The results are a more customer‐centric go‐to‐market strategy, a new lead generation infrastructure, better alignment with the sales process, and a marketing team that sees change as the name of the game. © 2006 Wiley Periodicals, Inc.
Strategic HR management creates value at Target
Authors: Ramlall Sunil J.
Published: February 2006

In the competitive jungles of discount retailing, Target consistently ranks among the fittest. Attributing its sustained high performance to the successful Target brand, the company has tapped every employee to be a brand manager. Four core strategies of the HR function, which operates as a full business partner at Target, have been keys to building and motivating a workforce that creates value for customers and stakeholders. © 2006 Wiley Periodicals, Inc.
Adsorption of some benzohydroxamic acid derivatives on copper oxide: assignment and interpretation of SERS spectra
Authors: Blajiev Orlin , Terryn Herman , Hubin Annick , Soukupova Ludmila , Geerlings Paul
Published: February 2006

The general aim of this work is to obtain information about the adsorption geometry of several benzohydroxamic acid (BHA) derivatives deposited on copper oxide. The investigation is done by means of surface enhanced Raman spectroscopy (SERS). In order to interpret the experimental information, an assignment of the SERS spectra is carried out. The process of assignment is supported by theoretical spectra derived from quantum‐chemical calculations. As the size of the molecules and the overall lack of symmetry of the adsorbate‐substrate system hinder the transparent description of the molecular vibrations, the local symmetry of the benzene is used as a basic classification feature. Such an approach is justified because, according to the theoretical spectra, the vibrations typical for the free benzene ring are conserved in the studied molecules. The deformations of the substituent and hydroxamic groups are added as a secondary descriptive element. On the basis of the spectrum assignment, the common vibrations typical for all investigated compounds and those used for identification that are pertinent to each of them, are classified. The surface selection rule is then qualitatively applied in order to derive information about the adsorption geometry. Copyright © 2006 John Wiley & Sons, Ltd.
An Organic/Inorganic Nanocomposite Consisting of Polymuconate and Silver Nanoparticles
Authors: Matsumoto Akikazu , Ishikawa Tomoyuki , Odani Toru , Oikawa Hidetoshi , Okada Shuji , Nakanishi Hachiro
Published: February 2006

Summary: We have fabricated a nanocomposite consisting of a crystalline polymer and fine metal particles. The intercalation of alkali metal ions into the layered polymer crystals, which were prepared by the solid state polymerization of dodecylammonium muconate, was achieved by heterogeneously stirring the reacting solid polymers in a solution of sodium hydroxide in methanol at room temperature. An ion exchange reaction was similarly carried out in a silver nitrate solution, which was followed by photoreduction, leading to the formation of fine silver particles in the crystalline polymer (the organic matrix). By controlling the amount of silver ions introduced, we have fabricated an organic/inorganic nanocomposite containing silver nanoparticles with well controlled size and distribution, the characteristics of which were measured by transmission electron microphotography, UV‐visible diffuse reflectance spectroscopy and a small‐angle X‐ray scattering method.

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A Concerted H‐Bonding Self‐Assembly‐Based Approach to Ladder Poly(silsesquioxane)
Authors: Deng Kuilin , Zhang Taoyi , Zhang Xiaojing , Zhang Aiqin , Xie Ping , Zhang Rongben
Published: February 2006

Summary: A soluble, regular, ethoxy‐capped, ladder poly(silsesquioxane) (EtO‐LPOAS) has been successfully synthesized by means of the concerted H‐bonding template of silanol and amido groups, through a new template monomer M: tetraethoxy disiloxane bisamide compound. EtO‐LPOAS was characterized by X‐ray diffraction (XRD), 29Si NMR spectroscopy and DSC measurements. The results confirm the presence of the regular, ladder structure of EtO‐LPOAS. This synthetic method has opened a new route to other new kinds of functional ladder poly(silsesquioxane)s.

Schematic overview of the mechanism for synthesis of EtO‐LPOAS.

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Schematic overview of the mechanism for synthesis of EtO‐LPOAS.
Synthesis and Orientation of Fluorene Containing Reactive Mesogens
Authors: Thiem Heiko , Jandke Markus , Hanft Doris , Strohriegl Peter
Published: February 2006

Summary: The synthesis of new fluorene containing photocrosslinkable reactive mesogens is described. Both monodisperse trimers or pentamers and oligomeric mixtures containing two photocrosslinkable acrylate end groups were obtained by Suzuki‐cross‐coupling reactions. The pentamer 12a shows an ideal phase behavior for orientation experiments with a broad nematic phase between the glass transition at −10 °C and 123 °C. In the oligomeric mixtures 14a–g the transition temperature from the nematic to the isotropic phase can be tailored from 100 to 310 °C by adjusting the molecular weight of the oligomers by end‐capping. This process can be easily characterized by MALDI‐TOF spectroscopy. The pentamer 12a and the oligomeric mixture 14c were oriented on rubbed polyimide layers and orientation ratios of 15:1 in photoluminescence were obtained. Experiments with different film thicknesses show that the orientation is not homogeneous throughout the film but decreases with increasing distance from the orientation layer.

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Optically Transparency and Light Color of Novel Highly Organosoluble Alicyclic Polyimides with 4‐tert‐Butylcyclohexyl Group
Authors: Liaw Der‐Jang , Huang Ching‐Cheng , Chen Wen‐Hsiang
Published: February 2006

Summary: Novel optically transparent and highly organosoluble alicyclic polyimides derived from bulky alicyclic diamine containing trifluoromethyl group on either side, 1,1‐bis[4‐(2‐trifluoromethyl‐4‐aminophenoxy)phenyl]‐4‐tert‐butylcyclohexane (BTFAPBC), were prepared. All polymers showed excellent solubility in various organic solvents like N‐methyl‐2‐pyrrolidinone (NMP), N,N‐dimethyl acetamide (DMAc), N,N‐dimethyl formamide (DMF), pyridine, cyclohexanone, and γ‐butyrolactone. The cut‐off wavelength and 80% transmission wavelength for polyimides ranged from 362 to 407 nm and 436 to 492 nm, respectively. Polyimides with alicyclic tert‐butylcyclohexyl cardo and trifluoromethyl substituents exhibited low dielectric constants ranging from 3.38 to 4.07 (at 1 KHz). Inherent viscosities of the polyimides were found to be in the range of 0.52–1.00 dL · g−1. Polyimides showed glass transition temperatures in the range of 231–262 °C, and possessed a coefficient of thermal expansion (CTE) of 66–79 ppm · °C−1. Thermogravimetric analyses of the polyimides revealed high thermal stability and decomposition temperature more than 450 °C in nitrogen atmosphere. The 10% weight loss temperature was found to be in the range of 453–544 and 413–502 °C in nitrogen and air atmospheres, respectively. The polyimide films had a tensile strength ranging from 84 to 100 MPa. The elongation at break varied from 6 to 12% and the tensile modulus varied from 1.1 to 2.1 GPa.

Synthesis of diamines, BTFAPBC, BTFAPAd, and BTFAPTC.

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Synthesis of diamines, BTFAPBC, BTFAPAd, and BTFAPTC.
Gradient Structure Polymer Obtained from a Homogeneous Mixture: Synthesis and Mechanical Properties
Authors: Noblet Guillaume , Désilles Nicolas , Lecamp Laurence , Lebaudy Philippe , Bunel Claude
Published: February 2006

Summary: The synthesis of a polymer that exhibits a gradient in mechanical properties, by means of a new method recently developed in our laboratory, is described. The synthesis involves two commercial resins, Laromer® LR 8986 and Laromer® LR 9000. In a first step, an acrylic double bond photopolymerization gradient is created under UV exposure thanks to the decay of UV light intensity through the sample thickness. In a second step, a thermal crosslinking reaction is realized to form a polyurethane network in order to set the obtained gradient. The experimental conditions required to obtain and keep the gradient are investigated by FT‐IR and UV spectroscopies. Thus, an 80% acrylic double bond conversion gradient is obtained in the ultimate 5 mm thick material. Dynamic mechanical analysis reveals an important difference between both sides of the material, the irradiated surface being hard at ambient temperature, meanwhile the underside remains soft.

Acrylic double bond conversion after 3 min of irradiation at 30 °C on materials of various thicknesses.

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Acrylic double bond conversion after 3 min of irradiation at 30 °C on materials of various thicknesses.
Synthesis of Cross‐Linked Comb Polysiloxane for Polymer Electrolyte Membranes
Authors: Karatas Yunus , Kaskhedikar Nitin , Burjanadze Marina , Wiemhöfer Hans‐Dieter
Published: February 2006

Summary: A series of comb‐like polysiloxanes was prepared as the base polymer for solvent‐free polymer electrolyte membranes. Hydrosilylation of poly(methylhydrosiloxane) (PMHS) was used to substitute hydrogen by the two types of side groups tetraethylene glycol allyl methyl ether and allyltrimethoxysilane (ATMS) with varying molar ratios between 5 and 40 mol‐% ATMS. The ATMS side groups served to cross‐link as‐prepared polymer electrolyte membranes after dissolving lithium trifluoromethylsulfonate (triflate) or lithium bis(trifluoromethylsulfonyl)imide. The ionic conductivities of these salt‐in‐polymer membranes prepared with a constant concentration of 10 wt.‐% lithium triflate showed a maximum conductivity of 4.6 × 10−5 S · cm−1 at 30 °C for 10 mol‐% ATMS substitution. In another series of experiments with the ATMS substitution held constant at 10 mol‐%, the salt concentration was varied yielding a maximum conductivity of 1.4 × 10−4 S · cm−1 at 30 °C for 12.5 wt.‐% lithium triflate.

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A Facile Method for Controlling the Molecular Weight of Hyperbranched Light‐Emitting Polymers
Authors: He Qingguo , Huang Hongmin , Bai Fenglian , Cao Yong
Published: February 2006

Summary: Two series of hyperbranched conjugated polymers were synthesized via an A3 + B2 type Wittig reaction. The molecular weights of the polymers were successfully tuned by simply changing the feed ratio of the monomers. Polymers with higher molecular weights presented more efficient photoluminescence, higher thermal stability and higher performance of LEDs.

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Introducing a Flat Model of the Silica‐Supported Bis(imino)pyridyl Iron(II) Polyolefin Catalyst
Authors: Han Wei , Müller Christian , Vogt Dieter , Niemantsverdriet Hans (J. W.) , Thüne Peter C.
Published: February 2006

Summary: A well‐defined flat model of a supported homogeneous polyolefin catalyst is prepared on the basis of an immobilized bis(imino)pyridyl iron complex on a super flat silica surface. The amount of supported catalyst precursor is quantified using XPS. This model catalyst remains active over extended periods, i.e., an average activity of 0.25 × 103 kg PE · (molCat · h · bar)−1 is obtained for 24 h of ethylene polymerization. The morphology of the nascent polyethylene film is investigated by SEM.

A side‐view SEM image of the PE produced from the supported bis(imino)pyridyl Fe catalyst.

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A side‐view SEM image of the PE produced from the supported bis(imino)pyridyl Fe catalyst.
Styrene Emulsion Polymerization above the CMC: New Evidence on Particle Nucleation by means of AFFFF
Authors: Carro Shirley , Herrera‐Ordonez Jorge
Published: February 2006

Summary: The number (N) and size distribution of particles (PSD) of a styrene emulsion polymerization above the CMC were studied by means of asymmetric flow‐field flow fractionation (AF4). Bimodal PSDs were obtained, suggesting that coagulation of the primary particles is not as extensive as would be expected, according to the coagulative mechanism. AF4 allowed it to be demonstrated that N is constant during interval II, and that the resolution limit of other particle sizing techniques can lead to erroneous mechanistic inferences, from the evolution of N.

Particle size distribution measured at low conversion for the emulsion polymerization of styrene, obtained by AF4 and DLS. The initial surfactant (S0), initiator (I0) and monomer (M0) concentrations are indicated in the figure.

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Particle size distribution measured at low conversion for the emulsion polymerization of styrene, obtained by AF4 and DLS. The initial surfactant (S0), initiator (I0) and monomer (M0) concentrations are indicated in the figure.
Strain Field Analysis and Kinetics of Crack Propagation of Binary Triblock Copolymer Blends
Authors: Satapathy Bhabani Kumar , Staudinger Ulrike , Weidisch Roland , Lach Ralf , Janke Andreas , Knoll Konrad
Published: February 2006

Summary:The crack toughness behaviour of binary styrene‐butadiene (SB) triblock copolymer blends of a thermoplastic block copolymer (LN3) and a thermoplastic elastomer (LN4) with different molecular architecture was studied using essential work of fracture (EWF) concept and was correlated to the morphological features from transmission electron microscopy (TEM). An increase in the crack toughness behaviour between 60 and 80 wt.‐% LN3 has been observed and is attributed to a change from cylindrical to lamellar morphology. The time‐resolved crack propagation studies have offered new dimensions to understand the kinetic aspects of fracture behaviour while the strain field analysis has explained the time‐dependent deformation behaviour to characterise the time dependence of the strain energy dissipation modes.

Load‐displacement diagrams of non essential work of fracture values of LN3/LN4 blends.

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Load‐displacement diagrams of non essential work of fracture values of LN3/LN4 blends.
Precise Block‐Copolymers by Efficient Coupling of End‐Functionalized Polymers Using Phosgene
Authors: Cotiuga Irina , Picchioni Francesco , Agarwal Uday S. , Staal Bastiaan B. P. , Vekemans Jef A. J. M. , Lemstra Piet J.
Published: February 2006

Summary: We report the synthesis of well‐defined block copolymers by covalent coupling of hydroxy end‐functionalized polymers. Using the high volatility of the coupling agent phosgene as compared to the solvent, very high conversion (up to 96%) is obtained in a one‐pot reaction with as little as 10−5 moles of each of the reacting polymers, even without prior purification of the as‐received reagents. This has potential as an alternative to the currently practiced method of sequential living polymerization of constituent monomers, with the added advantage of direct knowledge and control over the length distribution of each block.

Coupling of end‐functionalized polymers using phosgene to form block copolymers of controlled composition.

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Coupling of end‐functionalized polymers using phosgene to form block copolymers of controlled composition.
One‐Pot Fabrication of Supramolecular Polymer Particles via Situ Polymerization Stringed Assembly of a Two‐Monomer Microemulsion
Authors: Wang Yongxin , Qiu Zhaobin , Yang Wantai
Published: February 2006

Summary: A novel method, situ polymerization stringed assembly (SPSA), is proposed to prepare stable solid or hollow supramolecular polymer particles, which are assembled by numerous nanoparticles. By this method, the fabrication of primary nanoparticles (poly(methyl methacrylate), PMMA), the linkers (polyvinylpyrrolidone, PVP, chains) between the nanoparticles, and the final assembled solid or hollow particles could be achieved in just one‐pot by methyl methacrylate (MMA)/N‐vinylpyrrolidone (NVP) microemulsion polymerization under UV irradiation. The structures of the supramolecular particles can be changed from solid to hollow by tuning the mass ratio of MMA/NVP in the microemulsion. AFM, TEM, and SEM experiments are performed to identify the results.

AFM image of the PMMA/PVP solid particles obtained from the photopolymerization of the microemulsion containing 20 wt.‐% MMA, 10 wt.‐% NVP, and 5 × 10−2 wt.‐% BP.

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AFM image of the PMMA/PVP solid particles obtained from the photopolymerization of the microemulsion containing 20 wt.‐% MMA, 10 wt.‐% NVP, and 5 × 10−2 wt.‐% BP.
Nanocomposite Dendrimers Based on Cyclic Phosphazene Cores: Amorphous Materials for Electroluminescent Devices
Authors: Sudhakar Sundarraj , Sellinger Alan
Published: February 2006

Summary: A new family of solution‐processable, photoluminescent, nanocomposite dendrimers based on cyclic phosphazene (CP) cores have been prepared and characterized. The synthetic approach is based on the preparation of bromoaromatic‐functionalized CP cores by reacting selected bromophenolic compounds with the commercially available hexachlorocyclotriphosphazene in yields >90%. The bromophenyl‐functionalized CP cores are then reacted with N‐p‐tolylpyren‐1‐amine using Buchwald‐Hartwig amination chemistry to give the dendrimers of interest in yields >90%. The resultant dendrimers have high glass transition (>165 °C) and decomposition temperatures (>465 °C), are monodisperse (PDI < 1.05), have high purity via common chromatographic techniques, have high photoluminescent quantum efficiencies (83%), and form defect‐free amorphous films via spin/dip coating. A comparison to their molecular analogues is also provided to demonstrate the superior properties of the new nanocomposite dendrimers.

Structure of the cyclic phosphazene dendrimers.

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Structure of the cyclic phosphazene dendrimers.
Novel Metal‐Polyurethane Complexes with Enhanced Antimicrobial Activity
Authors: Francolini Iolanda , Ruggeri Valeria , Martinelli Andrea , D'Ilario Lucio , Piozzi Antonella
Published: February 2006

Summary: The silver coating of polymers has been intensively investigated in the last few decades as an effective non‐resistance‐inducing strategy to prevent medical device‐related infections. We have developed a completely new approach to incorporate silver ions in polymers by the synthesis of a carboxylated polyurethane able to coordinate Ag+. The obtained polymers possess mechanical properties suitable for the development of medical devices, without any risk of loss of activity. To minimize the risk of increasing antibiotic resistance, the metal ion‐containing polymers are loaded with ciprofloxacin, which possesses a different mechanism of antimicrobial action, thus a system able to inhibit Staphylococcus epidermidis and Pseudomonas aeruginosa growth for at least one month is developed.

SEM images showing a mature S. epidermidis biofilm on the surface of the carboxylated polyurethane (left) and the surface of the silver ion‐containing polyurethane free from bacterial colonization (right) after 48 h of incubation.

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SEM images showing a mature S. epidermidis biofilm on the surface of the carboxylated polyurethane (left) and the surface of the silver ion‐containing polyurethane free from bacterial colonization (right) after 48 h of incubation.