bluuebunny/crossref_metadata_2025_split huggingface dataset:
Metal‐Free 2,2,6,6‐Tetramethylpiperidin‐1‐yloxy Radical (TEMPO) Catalyzed Aerobic Oxidation of Hydroxylamines and Alkoxyamines to Oximes and Oxime Ethers
Authors: Wertz Sebastian , Studer Armido 
Published: October 2012

AbstractTEMPO‐Mediated oxidation of hydroxylamines (=hydroxyamines) and alkoxyamines to the corresponding oxime derivatives is reported (TEMPO=2,2,6,6‐tetramethylpiperidin‐1‐yloxy radical; Scheme 2). These environmentally benign oxidations proceed in good to excellent yields (Table 1). For alkoxyamines, oxidation to the corresponding oxime ethers can be performed by using dioxygen as a terminal oxidant in the presence of 5–10 mol‐% of TEMPO or 4‐substituted derivatives thereof as a catalyst (Scheme 3 and Table 2). Importantly, benzyl bromides can directly be transformed to oxime ethers via in situ alkoxyamine formation by a nucleophilic substitution followed by TEMPO‐mediated oxidation (Scheme 4 and Table 3).
Enantioselective Synthesis of (−)‐(R)‐Cordiachromene and (−)‐(R)‐Dictyochromenol Utilizing Intramolecular SNAr Reaction
Authors: Noda Yoshihiro , Yasuda Misato 
Published: October 2012

AbstractA simple and efficient enantioselective synthesis of chromene, (−)‐(R)‐cordiachromene (1), and (−)‐(R)‐dictyochromenol (2) has been accomplished. This convergent synthesis utilizes intramolecular SNAr reaction for the formation of chroman ring, and Seebach's method of ‘self‐reproduction of chirality’ should establish the (R)‐configuration of the C(2) side chain as key steps.
Asymmetric Syntheses of the Sex Pheromones of Pine Sawflies, Their Homologs and Stereoisomers
Authors: Zheng Jian‐Feng , Lan Hong‐Qiao , Yang Rui‐Feng , Peng Qi‐Long , Xiao Zhen‐Hua , Tuo Shi‐Chuan , Hu Kong‐Zhen , Xiang Yong‐Gang , Wei Zhen , Zhang Zhen , Huang Pei‐Qiang 
Published: October 2012

AbstractWe describe efficient and flexible enantioselective syntheses of the active enantiomers of the pheromones of pine sawflies, including the species Diprion jingyuanensis, their homologs and, stereoisomers, as well as those identified from the Chinese species Diprion jingyuanensis, i.e., 126. A total of 48 compounds, including acetates 78–101 and propanoates 102–125, have been synthesized. Our general approach towards these compounds originated from the commercially available chirons diethyl (S)‐ and (R)‐malates, as well as ethyl (R)‐3‐hydroxybutanoate. The Seebach asymmetric methylation was employed in a key step to control additional configuration.
Helical Structures of Bicyclic α‐Amino Acid Homochiral Oligomers with the Stereogenic Centers at the Side‐Chain Fused‐Ring Junctions
Authors: Anan Kosuke , Demizu Yosuke , Oba Makoto , Kurihara Masaaki , Doi Mitsunobu , Suemune Hiroshi , Tanaka Masakazu 
Published: October 2012

AbstractChiral bicyclic α‐amino acid (R,R)‐Ab5,6=c with stereogenic centers at the γ‐position of fused‐ring junctions, and its enantiomer (S,S)‐Ab5,6=c, were synthesized. The CD spectra of (R,R)‐Ab5,6=c oligomers indicated that the (R,R)‐Ab5,6=c hexapeptide formed a mixture of right‐handed (P)‐ and left‐handed (M)‐310‐helices, while, in the (R,R)‐Ab5,6=c nonapeptide, a right‐handed (P)‐310‐helix slightly dominated over the (M)‐helix. X‐Ray crystallographic analyses of (S,S)‐tripeptide and (R,R)‐hexapeptide revealed that both the tripeptide and hexapeptide formed a mixture of (P)‐ and (M)‐310‐helices, respectively. These results indicated that the side‐chain environments around the stereogenic centers are particularly important to control the helical‐screw handedness of foldamers.
The MoritaBaylisHillman Reaction of Chiral Highly Oxygenated Cyclopent‐2‐enones
Authors: Masusai Chonticha , Soorukram Darunee , Kuhakarn Chutima , Tuchinda Patoomratana , Pakawatchai Chaveng , Reutrakul Vichai , Pohmakotr Manat 
Published: October 2012

AbstractThe MoritaBaylisHillman (MBH) reactions of (4S,5R,7R,8R)‐ and (4R,5R,7R,8R)‐4‐hydroxy‐7,8‐dimethoxy‐7,8‐dimethyl‐6,9‐dioxaspiro[4.5]dec‐2‐en‐1‐ones (2 and 3, resp.) with aldehydes using various catalysts were studied. A combination of Bu3P/phenol in THF was found being optimum conditions giving the corresponding MBH adducts with high diastereoisomeric ratios. After separation, each stereomerically pure isomer of the MBH adducts was subjected to hydrolysis employing 1% aq. CF3COOH (TFA) in a water bath of an ultrasonic cleaner to afford the corresponding polyhydroxylated cyclopentenones in good yields.
New Aspects of 1,3‐Diphosphacyclobutane‐2,4‐diyls
Authors: Yoshifuji Masaaki , Hirano Yuichi , Schnakenburg Gregor , Streubel Rainer , Niecke Edgar , Ito Shigekazu 
Published: October 2012

Abstract1,3‐Di(tert‐butyl)‐2,4‐bis[2,4,6‐tri(tert‐butyl)phenyl]‐1,3‐diphosphacyclobutane‐2,4‐diyl was formed from [2,4,6‐tri(tert‐butyl)phenyl]phosphaacetylene and t‐BuLi. In addition, the X‐ray diffraction analysis was carried out, together with theoretical calculations of the structure and NMR data.
Nucleophilic Fluoroalkylation of α,β‐Unsaturated Carbonyl Compounds with α‐Fluorinated Sulfones: Investigation of the Reversibility of 1,2‐Additions and the Formation of 1,4‐Adducts
Authors: Shen Xiao , Ni Chuanfa , Hu Jinbo 
Published: October 2012

AbstractA detailed investigation of the reactions of PhSO2CF2H and PhSO2CH2F with (E)‐chalcone (=(E)‐1,3‐diphenylprop‐2‐en‐1‐one) at low temperatures revealed that these two reactions were kinetically controlled, and the ratios of 1,2‐ vs. 1,4‐adducts, which did not change much over time at these temperatures, reflect the relative rates of the two reaction pathways. The controlled experiments of converting the PhSO2CF2‐ and PhSO2CHF‐substituted 1,2‐adducts to 1,4‐adducts showed that these isomerizations are not favored due to the low stability and hard‐soft nature of PhSO2CF$\rm{{_{2}^{-}}}$ and PhSO2CHF− anions. Moreover, taking advantage of the remarkable stability and softness of (PhSO2)2CF− anion, an efficient thermodynamically controlled isomerization of (PhSO2)2CF‐substituted 1,2‐adduct to 1,4‐adduct was achieved for the first time.
Asymmetric Synthesis of β2‐homo‐tert‐Leucine via Radical Addition to Enantiopure N‐Fumaroylhexahydrobenzooxazolidin‐2‐one
Authors: Escudero‐Casao Margarita , Juaristi Eusebio 
Published: October 2012

Abstractβ‐Amino acids are key structural elements in unnatural peptides, peptidomimetics, and many other physiologically active compounds. In view of their importance, we have developed an efficient synthetic route that provides highly enantiomerically enriched (R)‐ and (S)‐H‐β2‐htLeu‐OH via highly diastereo‐ and regioselective addition of tert‐butyl radical to enantiomerically pure N‐fumaroyloxazolidinones, followed by removal of the chiral auxiliary, Curtius rearrangement, ester hydrolysis, and catalytic hydrogenolysis.
“I'm Just Kind of Winging It”: Preparing and Supporting Educators of Adult Refugee Learners
Authors: Perry Kristen H. , Hart Susan J. 
Published: October 2012

AbstractIn this qualitative case study, we explore local adult educators’ preparation to teach refugees, along with their professional development needs. This analysis focuses on 10 tutors and instructors in a midsize Southeastern city. Data collection involved an open‐ended questionnaire, semi‐structured interviews, and observations; analysis involved open coding, theme generation, data matrices, and participant checking. Findings indicated that most participants had some level of preparation, although the amount and nature of this preparation varied widely; yet, even those with teaching certification felt un‐ or under‐prepared to teach ESL and/or literacy to adult refugees. Participants needed relevant training, opportunities to connect with “people resources”, and other supports. We discuss implications for offering ongoing, targeted professional development for adult ESL educators.
Literacy Learning Within Community Action Projects for Social Change
Authors: Wright Dana E. , Mahiri Jabari 
Published: October 2012

AbstractThis case study describes the literacy development of a struggling reader over a seven‐month period as he engaged in a youth‐led participatory action research (PAR) project. The project's goal was for youth participants to develop a proposal for productive change in their local community and present it to community stakeholders. The study focused on ways the participants were supported in gaining skills in research, writing and oral communications. The study examines the process through which literacy skills improved for the youngest participant for whom the academic aspects of this project were extremely challenging. It describes curricular and pedagogical approaches during the process that led to his academic literacy improvements. Findings indicate the key components that increased this participant's literacy development were the caring, supportive environment that was established, an assets‐based approach and apprenticeship model as well as connections of the research project to real world purposes.
Foregrounding the Disciplines for Teacher Preparation in Secondary Literacy
Authors: Conley Mark W. 
Published: October 2012

AbstractThough there has been disagreement about the particular emphasis on the disciplines with literacy, there is a great deal of agreement that the disciplines matter. This article describes a course designed to prepare beginning teachers to engage in disciplinary literacy, or literacy‐related ways of knowing in a discipline. After researching a topic within their discipline, considering approaches to engage students in challenging texts and contemplating ways in which students might be challenged or struggle with a set of disciplinary ideas, teacher candidates guided in decisions about literacy goals and practices. By following this sequence, beginning teachers move from an over‐emphasis on pedagogy to connecting specific literacy practices to disciplinary contexts. The promise of this approach is that beginning teachers are more likely to understand relationships between disciplinary contexts and literacy and, as a result, will be more likely to sustain a focus on disciplinary literacy.
Reducing scar formation by regulation of IL‐1 and MMP‐9 expression by using sustained release of prednisolone‐loaded PDLL microspheres in a murine wound model
Authors: Wu Tsui‐Hsun , Hsu Sung‐Hao , Chang Mei‐Hwei , Huang Yi‐You 
Published: October 2012

AbstractIn this study, we provide a new pharmacological treatment, which may prevent scar formation on wound healing and/or plastic surgery wounds. We used prednisolone to reduce scar formation in wound excision. To prolong the drug effect, prednisolone of different amounts were encapsulated in biodegradable poly(D,L‐lactide) (PDLL) microspheres. In the in vitro cell healing study, prednisolone was markedly effective in reducing the growth rate of fibroblast cells according to electric cell‐substrate impedance sensing results. At a higher density of prednisolone, a slower growth rate was observed (ANOVA, p < 0.05). In rat models of skin wound healing studies, results show that in postsurgery days 7 and 14, all of the wound fibrosis areas administered with 0.5 and 5 mM of prednisolone‐loaded PDLL microspheres (PPM) were decreased by 6–116% compared with those of the control groups (ANOVA, p < 0.05). Adding the PPM led to reduce IL‐1β but increase MMP‐9 expression levels as compared with the control groups (ANOVA, p < 0.0001). These results implies that using sustained releasing prednisolone microspheres can regulate ECM generated from fibroblasts, can avoid excess proliferation and reduce the formation of scar tissue during wound regeneration by inhibiting the degree of inflammation. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
Design of core–shell gel beads for time‐programmed protein release
Authors: Suzuki Shiho , Asoh Taka‐Aki , Kikuchi Akihiko 
Published: October 2012

AbstractCalcium alginate gel beads were coated with calcium poly(γ‐glutamate) (Ca‐γ‐PGA) or its alkylate to modulate a release onset time of macromolecular drugs like proteins. Dextran release from coated alginate gel beads with γ‐PGA increased the onset release time from 13 min for bare alginate beads to 49 min for γ‐PGA‐coated alginate gel beads with diameters of about 0.6 mm. The γ‐PGA coating may act as a barrier to disintegration due to the swelling of alginate gels through ion exchange of Ca2+ with Na+. As the osmotic pressure increases inside the γ‐PGA capsule, the γ‐PGA layer eventually delaminates to form flakes and enables drug release. To further increase the onset release time, we modified the carboxyl groups of γ‐PGA with 1‐bromobutane to increase the hydrophobicity of the coating layers. By incorporating 20 mol % butyl groups, the onset release time increased to 87 min. Even for proteins, the hydrophobic polymer coating of the gels was effective at increasing the lag time. Similar to the release of dextran, proteins, albumin (bovine serum albumin), immunoglobulin G, and fibrinogen showed an S‐shaped release curve with onset release time, in which the onset release time depends on the molecular weight and their conformation. In conclusion, we successfully prepared modified alginate gel beads with injectable bead diameters and modulated the onset release time of macromolecular drugs. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
Inducible nitric oxide synthase inhibition increases MMP‐2 activity leading to imbalance between extracellular matrix deposition and degradation after polypropylene mesh implant
Authors: Souza‐Pinto Franciso J. P. , Moretti Ana I. S. , Cury Vivian , Marcondes Wagner , Velasco Irineu T. , Souza Heraldo P. 
Published: October 2012

AbstractProsthetic mesh implants are commonly used to correct abdominal wall defects. However, success of the procedure is conditioned by an adequate inflammatory response to the device. We hypothesized that nitric oxide produced by nitric oxide synthase 2 (NOS2) and MMP‐2 and ‐9 participate in response induced by mesh implants in the abdominal wall and, consequently, affect the outcome of the surgical procedure. In the first step, temporal inflammatory markers profile was evaluated. Polypropylene meshes were implanted in the peritoneal side of the abdominal wall of C57Black mice. After 2, 4, 7, 15, and 30 days, tissues around the mesh implant were collected and inflammatory markers were analyzed. In the second step, NOS2 activity was inhibited with nitro‐L‐arginine methyl ester (L‐NAME). Samples were collected after 15 days (when inflammation was reduced), and the inflammatory and tissue remodeling markers were investigated. Polypropylene mesh implant induced a pro‐inflammatory environment mediated by intense MMP‐2 and ‐9 activities, NO release, and interleukin‐1β production peaking in 7 days and gradually decreasing after 15 days. NOS2 inhibition increased MMP‐2 activity and resulted in a higher visceral adhesion incidence at the mesh implantation site when compared with non‐treated animals that underwent the same procedure. We conclude that NOS2‐derived NO is crucial for adequate response to polypropylene mesh implant integration in the peritoneum. NO deficiency results in an imbalance between extracellular matrix deposition/degradation contributing to visceral adhesions incidence. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
In vitro biological study of gelatin/PLG nanocomposite using MCF‐7 breast cancer cells
Authors: Haroun Ahmed A. , Abo‐Zeid Mona A. , Youssef Ahmed M. , Gamal‐Eldeen Amira 
Published: October 2012

AbstractThis work aimed to evaluate new materials to be carried out as scaffolds using breast cancer cells MCF‐7. These new nanocomposites were prepared through blending of gelatin with poly (DL‐lactide‐co‐glycolide) (PLG) in presence of titanium nanowires (TiO2) and cartilage powder (CP). The prepared nanomaterials were characterized using Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscope, and transmitting electron microscope. Moreover, the MCF‐7 cells were in vitro tested with apoptosis/necrosis assay, micronucleus test, and DNA fragmentation and MMT assay. TiO2 nanowires and CP particles have diameters around 28–128 and 17–20 nm, respectively. These were coated with gelatin matrix. Seeding of MCF‐7 cells with the prepared nanomaterials revealed high cell attachment to their surfaces and they were viable after 72 h. It has been shown that the prepared nanocomposites did not induce necrotic effects on MCF‐7 cells; however, they induced a significant DNA fragmentation in comparison with the nontreated control cells. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
Adsorption behavior of human plasma fibronectin on hydrophobic and hydrophilic Ti6Al4V substrata and its influence on bacterial adhesion and detachment
Authors: Vadillo‐Rodríguez Virginia , Pacha‐Olivenza Miguel A. , Gónzalez‐Martín M. Luisa , Bruque José M. , Gallardo‐Moreno Amparo M. 
Published: October 2012

AbstractBiomaterial implant‐associated infections, a common cause of medical devices' failure, are initiated by bacterial adhesion to an adsorbed protein layer on the implant material surface. In this study, the influence of protein surface orientation on bacterial adhesion has been examined using three clinically relevant bacterial strains known to express specific binding sites for human plasma fibronectin (HFN). HFN was allowed to adsorb on hydrophobic Ti6Al4V and physically modified hydrophilic Ti6Al4V substrata. Ellipsometric data reveal that the characteristics of the adsorbed protein layers primary depend on solid surface tension and the initial protein concentration in solution. In particular, HFN molecules adopt a more extended conformation on hydrophobic than hydrophilic surfaces, an effect that is more pronounced at low than at high initial protein concentrations. Moreover, the extended conformation of the protein molecules on these surfaces likely facilitates the exposure of specific sites for adhesion, resulting in the higher bacterial‐cell attachment observed regardless of the strain considered. Contact angle measurements and the analysis of the number of remaining adhering cells after being subjected to external forces further suggest that both specific and nonspecific (hydrophobic) interactions play an important role on bacterial attachment. This study is the first one to evaluate the influence of surface hydrophobicity on protein adsorption and its subsequent effect on bacterial adhesion using a material whose hydrophobicity was not modified using chemical treatments that potentially led to surface properties changes other than hydrophobicity. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
Molecular rectification in triangularly shaped graphene nanoribbons
Authors: Liu Hongmei , Wang Hongbo , Zhao Jianwei , Kiguchi Manabu 
Published: October 2012

AbstractWe present a theoretical study of electron transport in tailored zigzag graphene nanoribbons (ZGNRs) with triangular structure using density functional theory together with the nonequilibrium Green's function formalism. We find significant rectification with a favorite electron transfer direction from the vertex to the right edge. The triangular ZGNR connecting to the electrode with one thiol group at each terminal shows an average rectification ratio of 8.4 over the bias range from −1.0 to 1.0 V. This asymmetric electron transport property originates from nearly zero band gap of triangular ZGNR under negative bias, whereas a band gap opens under positive bias. When the molecule is connected to the electrode by multithiol groups, the current is enhanced due to strong interfacial coupling; however, the rectification ratio decreases. The simulation results indicate that the unique electronic states of triangular ZGNR are responsible for rectification, rather than the asymmetric anchoring groups. © 2012 Wiley Periodicals, Inc.
Convergence of sequences of Calderón‐Zygmund operators with application to wavelet expansions
Authors: Li Kangwei , Sun Wenchang 
Published: October 2012

AbstractWe present an extrapolation theorem for the convergence of sequences of Calderón‐Zygmund operators on various function spaces. We show that if a sequence of Calderón‐Zygmund operators with the same smoothness and decay parameters is convergent in operator norm on \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$L^2(\mathbb {R}^n)$\end{document}, then it is also convergent as operators on \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$L^p(\mathbb {R}^n)$\end{document}, 1 < p < ∞, and on a large class of Triebel‐Lizorkin, Besov and Hardy spaces. As an application, we show that as the sampling density tends to the infinity, the wavelet frame operator tends to the identity in operator norm on Triebel‐Lizorkin, Besov and Hardy spaces.
Europas Bildverarbeiter wachsen weiter
Authors: Maas Cor 
Published: October 2012

AbstractIndustrielle Bildverarbeitung ist ein unersetzbarer Bestandteil in der Automatisierungstechnik und darüber hinaus. Europäische Bildverarbeiter gehören seit langem zu den führenden Anbietern der Branche. Die jährliche Studie „European Vision Technology Market Statistics 2012”︁ der European Machine Vision Association bietet wertvolle Details über Verkaufszahlen, Märkte und technologische Trends in der Europäischen Bildverarbeitungsindustrie.
Mit der richtigen Beleuchtung besser „maschinell sehen”︁
Authors: Martin Daryl 
Published: October 2012

AbstractEffektive Prüflösungen in Anwendungen der Bildverarbeitung erfordern die genaue Abstimmung einer Reihe von Hardwarekomponenten. Eine der wichtigsten dabei ist die Beleuchtung, deren primäres Ziel es ist, kontrollierte Lichtverhältnisse zu schaffen, um präzise und wiederholbare Ergebnisse zu erzielen.
Nationale Messlaboratorien vergleichen ihre Feuchte‐Generatoren
Authors: Leggett Graham 
Published: October 2012

AbstractZu viel Feuchtigkeit fördert die Schimmelbildung im Haus und Korrosion im Auto. Im industriellen Bereich ist deshalb die Vermeidung selbst geringster Mengen von Wasser in Prozess‐ und Spülgasen in vielen Fertigungsverfahren eine äußerst kritische Aufgabe.
The narcissistic mask: An exploration of ‘the defensive grandiosity hypothesis’
Authors: Thomas Justin , Hashmi Amani Al , Chung Man Cheung , Morgan Keith , Lyons Minna 
Published: October 2012

ABSTRACTNarcissism has been conceptualized as involving attempts to defend against negative self‐schemata (implicit negative beliefs about one's own self‐worth). This idea has been termed the ‘mask model of narcissism’. This study explores the mask model, examining the association between extreme narcissistic personality traits and performance on a task purported to assess the influence of negative self‐schemata. Participants (n = 232) from the UK and the UAE completed the Narcissistic Personality Inventory and also performed an incidental learning task involving the surprise recall of self‐referential adjectives (traits). A greater recall of negative adjectives was viewed as indicative of negative self‐schemata. Looking at the sample as a whole, there were no associations between narcissistic traits and negative adjective recall. However, amongst those scoring in the upper quartile of the Narcissistic Personality Inventory, narcissism scores were positively correlated with the recall of negative adjectives even after controlling for age and memory. Narcissism may reflect self‐enhancement strategies rooted in negative self‐beliefs. Copyright © 2012 John Wiley & Sons, Ltd.