bluuebunny/crossref_metadata_2025_split huggingface dataset:
Efficient Epoxidation of Electron‐Deficient Alkenes with Hydrogen Peroxide Catalyzed by [γ‐PW10O38V2(μ‐OH)2]3−
Authors: Kamata Keigo , Sugahara Kosei , Yonehara Kazuhiro , Ishimoto Ryo , Mizuno Noritaka 
Published: June 2011

AbstractA divanadium‐substituted phosphotungstate, [γ‐PW10O38V2(μ‐OH)2]3− (I), showed the highest catalytic activity for the H2O2‐based epoxidation of allyl acetate among vanadium and tungsten complexes with a turnover number of 210. In the presence of I, various kinds of electron‐deficient alkenes with acetate, ether, carbonyl, and chloro groups at the allylic positions could chemoselectively be oxidized to the corresponding epoxides in high yields with only an equimolar amount of H2O2 with respect to the substrates. Even acrylonitrile and methacrylonitrile could be epoxidized without formation of the corresponding amides. In addition, I could rapidly (≤10 min) catalyze epoxidation of various kinds of terminal, internal, and cyclic alkenes with H2O2 under the stoichiometric conditions. The mechanistic, spectroscopic, and kinetic studies showed that the I‐catalyzed epoxidation consists of the following three steps: 1) The reaction of I with H2O2 leads to reversible formation of a hydroperoxo species [γ‐PW10O38V2(μ‐OH)(μ‐OOH)]3− (II), 2) the successive dehydration of II forms an active oxygen species with a peroxo group [γ‐PW10O38V2(μ‐η2:η2‐O2)]3− (III), and 3) III reacts with alkene to form the corresponding epoxide. The kinetic studies showed that the present epoxidation proceeds via III. Catalytic activities of divanadium‐substituted polyoxotungstates for epoxidation with H2O2 were dependent on the different kinds of the heteroatoms (i.e., Si or P) in the catalyst and I was more active than [γ‐SiW10O38V2(μ‐OH)2]4−. On the basis of the kinetic, spectroscopic, and computational results, including those of [γ‐SiW10O38V2(μ‐OH)2]4−, the acidity of the hydroperoxo species in II would play an important role in the dehydration reactivity (i.e., k3). The largest k3 value of I leads to a significant increase in the catalytic activity of I under the more concentrated conditions.
Chemistry and applications of nanocrystalline cellulose and its derivatives: A nanotechnology perspective
Authors: Peng B. L. , Dhar N. , Liu H. L. , Tam K. C. 
Published: June 2011

AbstractNanocrystalline cellulose (NCC) is an emerging renewable nanomaterial that holds promise in many different applications, such as in personal care, chemicals, foods, pharmaceuticals, etc. By appropriate modification of NCC, various functional nanomaterials with outstanding properties, or significantly improved physical, chemical, biological, as well as electronic properties can be developed. The nanoparticles are stabilised in aqueous suspension by negative charges on the surface, which are produced during the acid hydrolysis process. NCC suspensions can form a chiral nematic ordered phase beyond a critical concentration, i.e. NCC suspensions transform from an isotropic to an anisotropic chiral nematic liquid crystalline phase. Due to its nanoscale dimension and intrinsic physicochemical properties, NCC is a promising renewable biomaterial that can be used as a reinforcing component in high performance nanocomposites. Many new nanocomposite materials with attractive properties were obtained by the physical incorporation of NCC into a natural or synthetic polymeric matrix. Simple chemical modification on NCC surface can improve its dispersability in different solvents and expand its utilisation in nano‐related applications, such as drug delivery, protein immobilisation, and inorganic reaction template. This review paper provides an overview on this emerging nanomaterial, focusing on the surface modification, properties and applications of NCC.
Evolutionary design of optimum distillation column sequence
Authors: Boozarjomehry Ramin Bozorgmehry , Laleh Ali Pourahmadi , Svrcek William Y. 
Published: June 2011

AbstractSynthesis of the optimum distillation column sequence (DCS), which incorporates a huge search space composed of both conventional and complex arrangements, is a highly complicated combinatorial problem in the field of chemical process design and optimisation. In this study, a novel procedure for the synthesis of optimum DCS proposed by Boozarjomehry et al. [Boozarjomehry et al., Can. J. Chem. Eng. 87, 477–492 (2009)] is expanded to include the complex distillation arrangements. The method is based on evolutionary algorithms, and the total annual cost (TAC) is the main criterion used to screen alternatives. Efficient procedure has been proposed for encoding mechanism to include and classify various complex arrangements together with conventional distillation columns. All columns existing in each DCS alternative are designed using the most recommended short‐cut methods to estimate the TAC of the DCS. Four standard benchmark case studies are carried out to clearly demonstrate the excellent performance of the proposed method. The produced results for these problems indicate that the proposed method outperforms the other existing approaches in terms of flexibility, accuracy and comprehensiveness. © 2011 Canadian Society for Chemical Engineering
The CAPRA‐S score
Authors: Cooperberg Matthew R. , Hilton Joan F. , Carroll Peter R. 
Published: June 2011

AbstractBACKGROUND:The authors previously developed and validated the Cancer of the Prostate Risk Assessment (CAPRA) score to predict prostate cancer recurrence based on pretreatment clinical data. They aimed to develop a similar postsurgical score with improved accuracy via incorporation of pathologic data.METHODS:A total of 3837 prostatectomy patients in the Cancer of the Prostate Strategic Urologic Research Endeavor (CaPSURE™) national disease registry were analyzed. Cox regression was used to determine the predictive power of preoperative prostate‐specific antigen (PSA), pathologic Gleason score (pGS), surgical margins (SM), extracapsular extension (ECE), seminal vesicle invasion (SVI), and lymph node invasion (LNI). Points were assigned based on the relative weights of these variables in predicting recurrence. The new postsurgical score (CAPRA‐S) was tested and compared with a commonly cited nomogram with proportional hazards analysis, concordance (c) index, calibration plots, and decision‐curve analysis.RESULTS:Recurrence appeared in 16.8% of the men; actuarial progression‐free probability at 5 years was 78.0%. The CAPRA‐S was determined by adding up to 3 points for PSA, up to 3 points for pGS, 1 point each for ECE and LNI, and 2 points each for SM and SVI. The hazard ratio for each point increase in CAPRA‐S score was 1.54 (95% confidence interval, 1.49‐1.59), indicating a 2.4‐fold increase in risk for each 2‐point increase in score. The CAPRA‐S c‐index was 0.77, substantially higher than 0.66 for the pretreatment CAPRA score and comparable to 0.76 for the nomogram. The CAPRA‐S score performed better in both calibration and decision curve analyses.CONCLUSIONS:The CAPRA‐S offers good discriminatory accuracy, calibration, and ease of calculation for clinical and research settings. Cancer 2011;. © 2011 American Cancer Society.
Spectroscopy of Dibenzorubicene: Experimental Data for a Search in Interstellar Spectra
Authors: Rouillé Gaël , Steglich Mathias , Jäger Cornelia , Huisken Friedrich , Henning Thomas , Theumer Gabriele , Bauer Ingmar , Knölker Hans‐Joachim 
Published: June 2011

AbstractWe report on the characterization of dibenzo[cde,opq]rubicene (C30H14). The molecule was studied in solution at room temperature with absorption spectroscopy in the visible (vis) and ultraviolet (UV) wavelength ranges, and with emission spectroscopy. The infrared (IR), visible, ultraviolet, and vacuum ultraviolet (VUV) absorption spectra of a thin film were measured also at room temperature. In addition, the UV/vis absorption spectrum was measured at cryogenic temperatures using the matrix isolation spectroscopy technique. The interpretation of spectra was supported by theoretical calculations based on semiempirical and ab initio models, as well as on density functional theory. Finally, the results of the laboratory study were compared with interstellar spectra.
Experimental and Theoretical Investigation of Vibrational Spectra of Coordination Polymers Based on TCE‐TTF
Authors: Olejniczak Iwona , Łapiński Andrzej , Świetlik Roman , Olivier Jean , Golhen Stéphane , Ouahab Lahcène 
Published: June 2011

AbstractThe room‐temperature infrared and Raman spectra of a series of four isostructural polymeric salts of 2,3,6,7‐tetrakis(2‐cyanoethylthio)‐tetrathiafulvalene (TCE‐TTF) with paramagnetic (CoII, MnII) and diamagnetic (ZnII, CdII) ions, together with BF4− or ClO4− anions are reported. Infrared and Raman‐active modes are identified and assigned based on theoretical calculations for neutral and ionized TCE‐TTF using density functional theory (DFT) methods. It is confirmed that the TCE‐TTF molecules in all the materials investigated are fully ionized and interact in the crystal structure through cyanoethylthio groups. The vibrational modes related to the CC stretching vibrations of TCE‐TTF are analyzed assuming the occurrence of electron–molecular vibration coupling (EMV). The presence of the antisymmetric CC dimeric mode provides evidence that charge transfer takes place between TCE‐TTF molecules belonging to neighboring polymeric networks.
Cobalt Monolayer Islands on Ag(111) for ORR Catalysis
Authors: Loglio Francesca , Lastraioli Elisa , Bianchini Claudio , Fontanesi Claudio , Innocenti Massimo , Lavacchi Alessandro , Vizza Francesco , Foresti Maria Luisa 
Published: June 2011

AbstractThe design of a catalyst for one of the most important electrocatalytic reactions, the oxygen reduction reaction (ORR), was done following the most recent guidelines of theoretical studies on this topic. Aim of this work was to achieve a synergic effect of two different metals acting on different steps of the ORR. The catalytic activity of Ag, already known and characterized, was enhanced by the presence of a monolayer of cobalt subdivided into nanosized islands. To obtain such a controlled nanostructure, a novel method utilizing self‐assembled monolayers (SAMs) as templates was employed. In a recent study, we were able to perform a confined electrodeposition of cobalt onto Ag(111) in a template formed by selectively desorbing a short‐chain thiol (3‐mercaptopropionic acid, MPA) from binary SAMs using 1‐dodecanthiols (DDT). [32] This method allows for an excellent control of the morphology of the deposit by varying the molar ratio of the two thiols. Because cobalt does not deposit on silver at an underpotential, the alternative approach of surface limited redox replacement (SLRR) was used. This method, recently developed by Adžić et al.,13 consists of the use of a monolayer of a third metal, which can be deposited at an underpotential, as a template for the spontaneous deposition of a more noble metal. Herein, we choose zinc as template for the deposition of cobalt. Ag(111) crystals were covered by monolayer islands consisting of cobalt, with the surface atomic ratios ranging from 12 to 39 % for cobalt. The catalytic activity of such samples towards ORR was evaluated and the best improvement in activity was found to be that of the sample with a cobalt percentage of approximately 30 % with respect to the bare silver, which is in good agreement with theoretical hypotheses.
Macrophage and microglia ontogeny in the mouse visual system can be traced by the expression of Cathepsins B and D
Authors: Bejarano‐Escobar Ruth , Holguín‐Arévalo María Salud , Montero Juan Antonio , Francisco‐Morcillo Javier , Martín‐Partido Gervasio 
Published: June 2011

AbstractHere, we show a detailed chronotopographical analysis of cathepsin B and D expression during development of the mouse visual system. Both proteases were detected in large rounded/ameboid cells usually located in close relationship with prominent sites of extensive physiological cell death. In concordance with their morphological features and topographical distribution, we demonstrate that expressing cells corresponded with macrophages and microglial precursors. We found that as microglial precursors differentiated the expression of both cathepsins was down‐regulated. Of interest, cathepsin B and D transcripts were never observed in degenerating cells. Our findings point to a role for cathepsin D and B in cell debris degradation after apoptotic processes rather than promoting cell death, as proposed for other developmental models. Additionally their pattern of expression suggests a role in the maturation of the microglial precursors. Developmental Dynamics 240:1841–1855, 2011. © 2011 Wiley‐Liss, Inc.
Revisiting the Zintl–Klemm Concept: A2AuBi (A = Li or Na)
Authors: Wang Fei , Miller Gordon J. 
Published: June 2011

AbstractAlkali metal gold bismuthides, A2AuBi, are isoelectronic with alkali metal thallides, ATl = A2TlTl, and yet Na2AuBi adopts an orthorhombic structure with a 1‐D zigzag “ribbon” structural motif rather than the cubic double diamond structure type of NaTl as well as Li2AuBi. Using first principles quantum mechanical calculations applied to A2AuBi, hypothetical “A2HgPb,” and A2TlTl, and comprehensively decomposing the total energies into metallicity, ionicity, and covalency components to establish parallels with the qualitative Zintl–Klemm formalism, the factors determining the relative stability between the zigzag “ribbon” and the diamond network are examined. An interplay between volume‐dependent energy terms, i.e., metallicity or ionicity, and covalency among the electronegative components determines which structural motif is favored. In Na2AuBi, there are two factors stabilizing the zigzag “ribbon.” Au 5d states significantly interact with Bi 6p states, especially Au 5d with Bi 6pz to promote stronger Au–Bi covalent interactions than in the diamond network. This factor does not exist in Na2TlTl and “A2HgPb,” where Hg, Tl, and Pb 5d states are well localized. Secondly, the zigzag ribbons provide effective covalent interactions at larger volumes, as in Na2AuBi, while effective covalent interactions occur in the diamond network only at smaller volume, as in Li2AuBi.
Crystal Structure and Properties of Yb5Ni4Ge10
Authors: Peter Sebastian C. , Rayaprol Sudhindra , Francisco Melanie C. , Kanatzidis Mercouri G. 
Published: June 2011

AbstractThe new compound Yb5Ni4Ge10 was obtained as single crystals in high yield from reactions run in liquid indium. Single‐crystal X‐ray diffraction data showed that it crystallizes in the Sc5Co4Si10 structure type in the tetragonal space group P4/mbm. The structure is a three‐dimensional framework of [Ni4Ge10] atoms with voids filled by Yb atoms. The Ni and Ge atoms form pentagons, hexagons, and octagons along the ab one‐dimensional plane, which are interconnected along the c axis via Ni–Ge–Ni zigzag chains. Magnetic measurements reveal that Yb5Ni4Ge10 crystals show paramagnetic behavior with a lack of long‐range magnetic ordering down to 2 K. The magnetic susceptibility deviates from the Curie–Weiss law below 100 K, presumably because of crystal field effects from Yb3+ ions. In specific heat measurements, the compound exhibits non‐Fermi‐liquid‐like behavior at low temperatures.
Linear Synthesis of Chiral cycloSal‐Pronucleotides
Authors: Morales Edwuin Hander Rios , Román Cristina Arbelo , Thomann Jens Oliver , Meier Chris 
Published: June 2011

AbstractCycloSal‐nucleosyl‐phosphate triesters are a known class of highly effective nucleotide prodrugs (pronucleotides) of antivirally active nucleoside analogues. Until recently, the synthesis of these compounds always gave diastereoisomeric mixtures. Then, a convergent route for the stereospecific synthesis of cycloSal‐triesters was described to give isomerically pure cycloSal‐prodrugs for the treatment of viral diseases. Here, the development of a stereoselective synthesis of these pronucleotides using various chiral auxiliaries is described. In contrast to pyrrolidine‐ or pyrrolidinone derivatives it was found that a thiazolidine derived from valinol fulfilled all three requirements to act as a suitable chiral moiety, allowing: (i) strong chirality transfer, (ii) the formation of separable diastereoisomeric intermediates, and (iii) a suitable leaving group that allows the introduction of the nucleoside analogue (e.g., d4T) in the final step under mild reaction conditions. The title compounds were obtained with very high diastereoisomeric excesses of more than 95 %.
Biaryl‐Bridged Salalen Ligands and Their Application in Titanium‐Catalyzed Asymmetric Epoxidation of Olefins with Aqueous H2O2
Authors: Xiong Donglu , Hu Xiaoxue , Wang Shoufeng , Miao Cheng‐Xia , Xia Chungu , Sun Wei 
Published: June 2011

AbstractA series of biaryl‐bridged salalen ligands together with their titanium complexes have been designed and synthesized. The Ti complexes could serve as highly efficient catalysts for the asymmetric epoxidation of a wide range of olefins, giving the corresponding epoxides with high ee values.
Synthesis of Various Chiral 1,2,4‐Triazole‐Containing α‐Amino Acids from Aspartic or Glutamic Acids
Authors: Blayo Anne‐Laure , Brunel Frédéric , Martinez Jean , Fehrentz Jean‐Alain 
Published: June 2011

AbstractStarting from N‐ and C‐protected aspartic or glutamic acids, new unnatural α‐amino acids containing 3,4,5‐trisubstituted 1,2,4‐triazole heterocycles on their side chains have been synthesized. Two points of diversity could easily be achieved on the heterocyclic moiety, which could easily be incorporated in peptide sequences to modify or improve their pharmacokinetic properties.
The motivation to diet in young women: Fear is stronger than hope
Authors: Dalley Simon E. , Buunk Abraham P. 
Published: June 2011

AbstractThis research examined the relative impact of a hoped‐for, thin body and a feared, overweight body on weight‐loss dieting (WLD) motivation. We hypothesised that the women most motivated to engage in WLD would report a higher similarity to, and a higher cognitive availability of, a feared, overweight body. In study 1, WLD motivation was operationalized as WLD intention and in study 2 as a food choice (chocolate bar versus low‐fat snack bar). As expected, those most similar to the feared body and who had a highly available overweight body had the greatest intention to engage in WLD, and were more likely to choose a low‐fat snack over a chocolate bar. The implications of our findings for future research as well as the development of eating pathology in college women are discussed. Copyright © 2011 John Wiley & Sons, Ltd.
On the meaningfulness of existence: When life salience boosts adherence to worldviews
Authors: van Tilburg Wijnand A. P. , Igou Eric R. 
Published: June 2011

AbstractWe investigated when and how life salience boosts adherence to worldviews. It was hypothesized that, similar to thoughts of mortality, thoughts about a meaningful existence increase adherence to worldviews. Study 1a, 1b, and 1c yielded support for the symmetric effects of life and mortality salience on existential thoughts and worldview adherence. Furthermore, study 2 showed that contemplating life's meaningfulness (versus meaninglessness) increased adherence to worldviews. Study 3 showed increased worldview adherence when contemplating life's meaningfulness (versus meaninglessness), and provided additional evidence that the effect on worldview adherence was mediated by the appraisals of life's meaningfulness. Finally, study 4 suggests that both reflecting on life and mortality leads to more worldview adherence under conditions of meaningful life appraisals. The findings are discussed with respect to research in existential psychology. Copyright © 2011 John Wiley & Sons, Ltd.
The impact of Gacaca tribunals in Rwanda: Psychosocial effects of participation in a truth and reconciliation process after a genocide
Authors: Rimé Bernard , Kanyangara Patrick , Yzerbyt Vincent , Paez Dario 
Published: June 2011

AbstractVictims (N = 200) of the 1994 genocide in Rwanda and prisoners (N = 184) accused of genocidal acts reported their genocide‐related emotions and outgroup perceptions before and after their participation to Truth and Reconciliation Gacaca trials. So did control groups of victims (N = 195) and prisoners (N = 176) not yet exposed to Gacaca. The data supported Durkheim's model of social rituals as cultural tools for transforming emotions, reasserting norms, and enhancing cohesion. Specifically, participation entailed the general reactivation of resignation negative emotions, the enhancement of shame among prisoners, and the decrease of shame among victims, whereas the opposite pattern occurred for antagonist emotions. Participation also enhanced social integration by reducing perceived outgroup homogeneity, decreasing ingroup self‐categorization, and increasing positive stereotypes among both victim and prisoner participants. Moreover, the increase in genocide‐related emotions resulting from participation was associated to positive changes outcomes, suggesting that the increase of negative emotions is an important mechanism at work in collective events of this type. Enhancement of the perception of a positive emotional climate (solidarity and trust) was limited to perpetrator participants. Together, these findings show that Durkheim's model can be extended to restorative justice trials involving both victims and perpetrators. Copyright © 2011 John Wiley & Sons, Ltd.
Serine/threonine‐protein phosphatase 1 α levels are paralleling olfactory memory formation in the CD1 mouse
Authors: Winding Christiana , Sun Yanwei , Höger Harald , Bubna‐Littitz Hermann , Pollak Arnold , Schmidt Peter , Lubec Gert 
Published: June 2011

AbstractAlthough olfactory discrimination has already been studied in several mouse strains, data on protein levels linked to olfactory memory are limited. Wild mouse strains Mus musculus musculus, Mus musculus domesticus and CD1 laboratory outbred mice were tested in a conditioned odor preference task and trained to discriminate between two odors, Rose and Lemon, by pairing one odor with a sugar reward. Six hours following the final test, mice were sacrificed and olfactory bulbs (OB) were taken for gel‐based proteomics analyses and immunoblotting. OB proteins were extracted, separated by 2‐DE and quantified using specific software (Proteomweaver). Odor‐trained mice showed a preference for the previously rewarded odor suggesting that conditioned odor preference occurred. In CD1 mice levels, one out of 482 protein spots was significantly increased in odor‐trained mice as compared with the control group; it was in‐gel digested by trypsin and chymotrypsin and analyzed by tandem mass spectrometry (nano‐ESI‐LC‐MS/MS). The spot was unambiguously identified as serine/threonine‐protein phosphatase PP1‐α catalytic subunit (PP‐1A) and differential levels observed in gel‐based proteomic studies were verified by immunoblotting. PP‐1A is a key signalling element in synaptic plasticity and memory processes and is herein shown to be paralleling olfactory discrimination representing olfactory memory.