bluuebunny/crossref_metadata_2025_split huggingface dataset:
The self‐healing mechanism of an industrial acrylic elastomer
Authors: Fan Fan , Szpunar Jerzy 
Published: March 2015

ABSTRACTThe self‐healing materials attract a lot of attention as self‐healing ability considerably improves reliability of service and extends the life time of materials. However, the present self‐healing materials lack the mechanical strength and thus cannot be used in practical applications. The industrial elastomer (VHB 4910) is a strong polymer, which has been used as dielectric actuator. Surprisingly, we observed that VHB 4910 has autonomic self‐healing ability. As this is an acrylic polymer, we analyzed the hydrogen bonding between carbonyl and hydroxyl groups and demonstrated that this bonding and the molecular chain entanglement contributes to its self‐healing ability. The tensile test, X‐ray diffraction (XRD), Raman, and Fourier transform infrared (FTIR) spectroscopy were employed to analyze the self‐healing processes. This study provides an insight into the mechanism of self‐healing behavior and ability of VHB 4910 to recover its strength. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42135.
Development Strategies for Pacific Island Economies: Is There a Role for the Cultural Industries?
Authors: Throsby David 
Published: March 2015

AbstractAmongst the range of possible strategies to deal with ongoing development challenges facing the Pacific Island economies, one that has some potential is a policy focus on stimulating the creative or cultural industries. This article reviews the rise in interest around the world in the concept of the so‐called creative economy and its role in sustainable development. This interest has particular relevance at the present time in the light of international efforts to raise the profile of culture in development, especially with the replacement in 2015 of the Millennium Development Goals with a new set of sustainable development objectives. The article outlines the current state of the cultural industries' contribution to growth in the Pacific region, and discusses opportunities and obstacles affecting their further development. The article concludes by identifying some important considerations to be taken into account in the design of effective policy strategies in this area in the future.
Mechanoluminescence of Ba2MgSi2O7 doped with Eu2+ and Dy3+ phosphor by impulsive deformation
Authors: Shrivastava R. , Kaur J. , Chandra B. P. 
Published: March 2015

AbstractDi‐barium magnesium silicate phosphor doped with Eu2+ and Dy3+ was prepared using a solid‐state reaction technique under a reducing atmosphere. The sample underwent impulsive deformation by impact from a piston for mechanoluminescence (ML) investigations. The temporal ML characteristics of the phosphor were observed, which expressed a single sharp peak with a long decaying period. To investigate the luminescence centre responsible for the ML peak, the ML spectrum of the phosphor was also observed. The recorded ML spectrum was similar in shape and peak wavelength to the photoluminescence (PL) spectrum, which verifies the existence of a single emission centre due to the transition of Eu2+ ions, i.e. transitions from any of the sublevels of the 4f65d1 configuration to the 8S7/2 level of the 4f7 configuration. Decay rates for different impact velocities were also calculated using curve‐fitting techniques. The time of the ML peak and the rate of decay did not change significantly with respect to increasing impact velocity of the load and peak ML intensity varied linearly. The mechanism of the ML emission was also discussed. Copyright © 2015 John Wiley & Sons, Ltd.
Meta-analysis of the effect of goal-directed therapy on bowel function after abdominal surgery
Authors: Gómez-Izquierdo J C , Feldman L S , Carli F , Baldini G 
Published: March 2015

AbstractBackgroundIntraoperative goal-directed therapy (GDT) was introduced to titrate intravenous fluids, with or without inotropic drugs, based on objective measures of hypovolaemia and cardiac output measurements to improve organ perfusion. This meta-analysis aimed to determine the effect of GDT on the recovery of bowel function after abdominal surgery.MethodsMEDLINE, Embase, the Cochrane Library and PubMed databases were searched for randomized clinical trials and cohort studies, from January 1989 to June 2013, that compared patients who did, or did not, receive intraoperative GDT, and reported outcomes on the recovery of bowel function. Time to first flatus and first bowel motion, time to tolerate oral diet, postoperative nausea and vomiting, and primary postoperative ileus were included.ResultsThirteen trials with 1399 patients were included in the analysis. GDT shortened the time to the first bowel motion (weighted mean difference (WMD −0·67, 95 per cent c.i. −1·23 to −0·11; P = 0·020) and time to tolerate oral intake (WMD −0·95, −1·81 to −0·10; P = 0·030), and reduced postoperative nausea and vomiting (risk difference −0·15, −0·26 to −0·03; P = 0·010). When only high-quality studies were included, GDT reduced only the time to tolerate oral intake (WMD −1·18, −2·03 to −0·33; P = 0·006). GDT was more effective outside enhanced recovery programmes and in patients undergoing colorectal surgery.ConclusionGDT facilitated the recovery of bowel function, particularly in patients not treated within enhanced recovery programmes and in those undergoing colorectal operations.
How Transitional Justice Processes and Official Apologies Influence Reconciliation: The Case of the Chilean ‘Truth and Reconciliation’ and ‘Political Imprisonment and Torture’ Commissions
Authors: Cárdenas Manuel , Páez Darío , Rimé Bernard , Arnoso Maitane 
Published: March 2015

ABSTRACTPerceptions of the ‘Truth and Reconciliation’ and ‘Political Imprisonment and Torture’ commissions and related beliefs, emotions and socio‐emotional climate were analysed in people affected and unaffected by past political violence in Chile (N = 1278). People directly affected regard institutional apologies as less sincere and effective, and they were more critical of the commissions. Those who have a positive appraisal of the commissions, compared with people who disagree with the commissions activities, are less prone to forget past collective violence; report higher levels of negative emotions, such as shame, and positive ones, such as pride and hope, about the collective past; and consider that the commissions contributed to knowing the truth about what happened to victims and helped bring human rights violators to justice. Those appraising the commissions in a positive fashion also perceive a more positive emotional climate and inter‐group trust, have more confidence in institutions and report more universalistic values. A multiple‐regression analysis suggests that commissions play a relatively successful role as transitional justice rituals, reinforcing reconciliation. Copyright © 2015 John Wiley & Sons, Ltd.
Oxygen Reduction at Shape‐Controlled Platinum Nanoparticles and Composite Catalysts Based on (100)Pt Nanocubes on Microporous–Mesoporous Carbon Supports
Authors: Grozovski Vitali , Kasuk Heili , Nerut Jaak , Härk Eneli , Jäger Rutha , Tallo Indrek , Lust Enn 
Published: March 2015

AbstractThe electrochemical oxygen reduction reaction (ORR) on bare (100)Pt nanoparticles supported by molybdenum‐carbide‐derived carbon [(100)Pt–C(Mo2C)] with high specific surface area and controlled microporosity–mesoporosity, pore size distribution, electrical conductivity, and corrosion stability was studied in 0.5 M H2SO4 solution by using rotating‐disk‐electrode and cyclic voltammetry methods. The C(Mo2C) powder was prepared from Mo2C at a fixed chlorination temperature (750 °C). Pt nanoparticles were prepared through colloid chemistry and deposited onto/into C(Mo2C) and Vulcan XC72 carbon supports for comparison. The ORR cathodic current densities and half‐wave potentials strongly depend on the characteristics of the carbon material used as the support. High values for the ORR current density were calculated for (100)Pt–C(Mo2C) and the half‐wave potential is nearly 80 mV more positive compared with that for the (100)Pt–Vulcan XC72 catalyst with a similar catalyst loading.
Divalent Transition‐Metal‐Ion Stress Induces Prodigiosin Biosynthesis in Streptomyces coelicolor M145: Formation of Coeligiosins
Authors: Morgenstern Anne , Paetz Christian , Behrend Anne , Spiteller Dieter 
Published: March 2015

AbstractThe bacterium Streptomyces coelicolor M145 reacts to transition‐metal‐ion stress with myriad growth responses, leading to different phenotypes. In particular, in the presence of Co2+ ions (0.7 mM) S. coelicolor consistently produced a red phenotype. This phenotype, when compared to the wild type, differed strongly in its production of volatile compounds as well as high molecular weight secondary metabolites. LC‐MS analysis revealed that in the red phenotype the production of the prodigiosins, undecylprodigiosin and streptorubin B, was strongly induced and, in addition, several intense signals appeared in the LC‐MS chromatogram. Using LC‐MS/MS and NMR spectroscopy, two new prodigiosin derivatives were identified, that is, coeligiosin A and B, which contained an additional undecylpyrrolyl side chain attached to the central carbon of the tripyrrole ring system of undecylprodigiosin or streptorubin B. This example demonstrates that environmental factors such as heavy metal ion stress can not only induce the production of otherwise not observed metabolites from so called sleeping genes but alter the products from well‐studied biosynthetic pathways.
Effect of Support on Metathesis of n‐Decane: Drastic Improvement in Alkane Metathesis with WMe5 Linked to Silica–Alumina
Authors: Samantaray Manoja K. , Dey Raju , Abou‐Hamad Edy , Hamieh Ali , Basset Jean‐Marie 
Published: March 2015

Abstract[WMe6] (1) supported on the surface of SiO2–Al2O3(500) (2) has been extensively characterized by solid‐state NMR spectroscopy, elemental analysis, and gas quantification, which clearly reveal the formation of a mixture of monopodal and bipodal species with the migration of methyl from W to Al. The supported species SiO2–Al2O3(500) (2) transformed at 120 °C into two types of carbynic centers, one of which is cationic and the other neutral. These species are very efficient for the metathesis of n‐decane. Comparison with already‐synthesized neutral bipodal tungsten indicates that the high increase in activity is due to the cationic character of the grafted tungsten.
Platinum Oxoboryl Complexes as Substrates for the Formation of 1:1, 1:2, and 2:1 Lewis Acid–Base Adducts and 1,2‐Dipolar Additions
Authors: Bertsch Stefanie , Brand Johannes , Braunschweig Holger , Hupp Florian , Radacki Krzysztof 
Published: March 2015

AbstractThe oxoboryl complex trans‐[(Cy3P)2BrPt(BO)] (2) reacts with the Group 13 Lewis acids EBr3 (E=Al, Ga, In) to form the 1:1 Lewis acid–base adducts trans‐[(Cy3P)2BrPt(BOEBr3)] (6–8). This reactivity can be extended by using two equivalents of the respective Lewis acid EBr3 (E=Al, Ga) to form the 2:1 Lewis acid–base adducts trans‐[(Cy3P)2(Br3Al‐Br)Pt(BOAlBr3)] (18) and trans‐[(Cy3P)2(Br3Ga‐Br)Pt(BOGaBr3)] (15). Another reactivity pattern was demonstrated by coordinating two oxoboryl complexes 2 to InBr3, forming the 1:2 Lewis acid–base adduct trans‐[{(Cy3P)2BrPt(BO)}2InBr3] (20). It was also possible to functionalize the BO triple bond itself. Trimethylsilylisothiocyanate reacts with 2 in a 1,2‐dipolar addition to form the boryl complex trans‐[(Cy3P)2BrPt{B(NCS)(OSiMe3)}] (27).
Discrete Stimuli‐Responsive Multirotaxanes with Supramolecular Cores Constructed through a Modular Approach
Authors: Wang Wei , Sun Bin , Wang Xu‐Qing , Ren Yuan‐Yuan , Chen Li‐Jun , Ma Jianqiu , Zhang Yanyan , Li Xiaopeng , Yu Yihua , Tan Hongwei , Yang Hai‐Bo 
Published: March 2015

AbstractThe synthesis of discrete multirotaxanes with well‐defined structures remains a great challenge. Herein, we present the successful construction of diverse discrete multirotaxanes with well‐defined supramolecular metallacycles as cores by a modular approach. Moreover, these novel multirotaxanes featured a stimuli‐responsive property that enabled the introduction and removal of the bromide anion by taking advantage of dynamic nature of the supramolecular metallacycle scaffold. Through the combination of rotaxane‐containing prefunctionalized building blocks with the corresponding different organoplatinum(II) acceptor building blocks (60, 120, or 180°), diverse discrete multirotaxanes with well‐defined metallacycles (rhomboid or hexagon) as cores as well as certain numbers of rotaxane units were successfully obtained quantitatively by means of coordination‐driven self‐assembly. Furthermore, owing to the existence of a dynamic metallacycle as the supramolecular cores, the resultant multirotaxanes showed anion‐induced disassembly and reassembly properties, which allowed for the reversible transformation between multirotaxanes and the corresponding individual rotaxane‐containing building blocks. Therefore, this research not only enriches the family of discrete multirotaxanes, but also provides a novel strategy for the construction of “smart” stimuli‐responsive multirotaxane systems.
Nazarov Cyclization of Divinyl and Arylvinyl Epoxides: Application in the Synthesis of Resveratrol‐Based Natural Products
Authors: Sudhakar Gangarajula , Satish Kovela 
Published: March 2015

AbstractNew variation in the Nazarov cyclization has been developed by preparing divinyl and arylvinyl epoxides as pentadienyl cation precursors for the first time. Highly substituted cyclopentadienes, hydrindienes, and indenes were synthesized to demonstrate the compatibility of this reaction with substrates bearing a variety of substitutions and having different types of epoxides. Application of this method in the synthesis of resveratrol‐based natural products was also demonstrated.
Unraveling Ultrafast Photoinduced Proton Transfer Dynamics in a Fluorescent Protein Biosensor for Ca2+ Imaging
Authors: Tang Longteng , Liu Weimin , Wang Yanli , Zhao Yongxin , Oscar Breland G. , Campbell Robert E. , Fang Chong 
Published: March 2015

AbstractImaging Ca2+ dynamics in living systems holds great potential to advance neuroscience and cellular biology. G‐GECO1.1 is an intensiometric fluorescent protein Ca2+ biosensor with a Thr‐Tyr‐Gly chromophore. The protonated chromophore emits green upon photoexcitation via excited‐state proton transfer (ESPT). Upon Ca2+ binding, a significant population of the chromophores becomes deprotonated. It remains elusive how the chromophore structurally evolves prior to and during ESPT, and how it is affected by Ca2+. We use femtosecond stimulated Raman spectroscopy to dissect ESPT in both the Ca2+‐free and bound states. The protein chromophores exhibit a sub‐200 fs vibrational frequency shift due to coherent small‐scale proton motions. After wavepackets move out of the Franck–Condon region, ESPT gets faster in the Ca2+‐bound protein, indicative of the formation of a more hydrophilic environment. These results reveal the governing structure–function relationship of Ca2+‐sensing protein biosensors.
Straightforward Synthesis of 5‐Bromopenta‐2,4‐diynenitrile and Its Reactivity Towards Terminal Alkynes: A Direct Access to Diene and Benzofulvene Scaffolds
Authors: Kerisit Nicolas , Toupet Loïc , Larini Paolo , Perrin Lionel , Guillemin Jean‐Claude , Trolez Yann 
Published: March 2015

AbstractThe high‐yielding synthesis of 5‐bromopenta‐2,4‐diynenitrile (BrC5N) was achieved for the first time. Its reactivity with triisopropylsilylacetylene and triisopropylsilylbutadiyne in the presence of copper and palladium as co‐catalysts and diisopropylamine was evaluated. It revealed an unprecedented cascade reaction leading to a diene in one case and to a benzofulvene in the other case, with a unique structure. Both of them were characterized by X‐ray crystallography, among other techniques. The mechanism of the reaction leading to the diene was investigated experimentally. Theoretical calculations at the DFT level suggest that the mechanism leading to the benzofulvene relies on a hexa‐dehydro Diels–Alder (HDDA)‐type of mechanism. This work constitutes an example of an unanticipated reactivity leading to an important increase of chemical complexity.
Tungstate Supported on Periodic Mesoporous Organosilica with Imidazolium Framework as an Efficient and Recyclable Catalyst for the Selective Oxidation of Sulfides
Authors: Karimi Babak , Khorasani Mojtaba , Bakhshandeh Rostami Fatemeh , Elhamifar Dawood , Vali Hojatollah 
Published: March 2015

AbstractA catalyst based on immobilization of tungstate ions (WO42−) inside the mesochannels of periodic mesoporous organosilica comprising bridged ionic liquid (1,3‐bis(3‐trimethoxysilylpropyl)imidazolium chloride) has been synthesized and characterized. This catalyst was then employed for the selective oxidation of organic sulfides to the corresponding sulfoxides or sulfones. The final synthesized catalyst was characterized by various techniques such as nitrogen sorption analysis, transmission electron microscopy, and thermogravimetric analysis. The catalyst was also applied to the selective oxidation of sulfides containing readily oxidizable functional groups such as hydroxyl, allylic, and even challenging aliphatic sulfides. Interestingly, it was found that on changing the reaction medium from aqueous methanol to aqueous acetonitrile, the product selectivity was changed successfully from sulfoxide to sulfone with good to excellent yields. Moreover, the catalyst can also be recovered and reused efficiently in nine subsequent reaction cycles without any remarkable decrease in the catalyst activity and selectivity.
Real‐time cytometric assay of nitric oxide and superoxide interaction in peripheral blood monocytes: A no‐wash, no‐lyse kinetic method
Authors: Balaguer Susana , Diaz Laura , Gomes Angela , Herrera Guadalupe , O'Connor José‐Enrique , Urios Amparo , Felipo Vicente , Montoliu Carmina 
Published: March 2015

BackgroundNitric oxide (NO) and its related reactive nitrogen species (RNS) and reactive oxygen species (ROS) are crucial in monocyte responses against pathogens and also in inflammatory conditions. Central to both processes is the generation of the strong oxidant peroxynitrite (ONOO) by a fast reaction between NO and superoxide anion. ONOO is a biochemical junction for ROS‐ and RNS cytotoxicity and causes protein nitrosylation. Circulating by‐products of protein nitrosylation are early biomarkers of inflammation‐based conditions, including minimal hepatic encephalopathy in cirrhotic patients (Montoliu et al., Am J Gastroenterol 2011; 106:1629–1637). In this context, we have designed a novel no‐wash, no‐lyse real‐time flow cytometry assay to detect and follow‐up the NO‐ and superoxide‐driven generation of ONOO in peripheral blood monocytes.MethodsWhole blood samples were stained with CD45 and CD14 antibodies plus one of a series of fluorescent probes sensitive to RNS, ROS, or glutathione, namely 4‐amino‐5‐methylamino‐2',7'‐difluorofluorescein diacetate, dihydrorhodamine 123, MitoSOX Red, dihydroethidium, and 5‐chloromethylfluorescein diacetate. Samples were exposed sequentially to a NO donor and three different superoxide donors, and analyzed in real time by kinetic flow cytometry. Relevant kinetic descriptors, such as the rate of fluorescence change, were calculated from the kinetic plot.ResultsThe generation of ONOO, which consumes both NO and superoxide, led to a decrease in the intensity of the cellular fluorescence of the probes sensitive to these molecules.ConclusionThis is a fast and simple assay that may be used to monitor the intracellular generation of ONOO in physiological, pathological, and pharmacological contexts. © 2015 International Clinical Cytometry Society
Contrasting responses to Pleistocene climate changes: a case study of two sister species Allium cyathophorum and A. spicata (Amaryllidaceae) distributed in the eastern and western Qinghai–Tibet Plateau
Authors: Wang Xinyu , Li Yuanshuo , Liang Qianlong , Zhang Lei , Wang Qian , Hu Huan , Sun Yongshuai 
Published: March 2015

AbstractIt has been hypothesized that species occurring in the eastern and the western Qinghai–Tibet Plateau (QTP) responded differently to climate changes during the Pleistocene. Here, we test this hypothesis by phylogeographic analysis of two sister species, Allium cyathophorum and A. spicata. We sequenced two chloroplast DNA (cpDNA) fragments (accD‐psaI and the rpl16 intron) of 150 individuals, and the nuclear (ITS) region of 114 individuals, from 19 populations throughout the distributional ranges of these species. The divergence between the two species was dated at 779 ‐ 714 thousand years before the present and was likely initiated by the most major glaciation in the QTP. Analysis of chlorotype diversity showed that A. spicata, the species occurring in the western QTP, contains much lower genetic diversity (0.25) than A. cyathophorum (0.93), which is distributed in the eastern QTP. Moreover, multiple independent tests suggested that the A. spicata population had expanded recently, while no such expansion was detected in A. cyathophorum, indicating a contrasting pattern of responses to Pleistocene climate changes. These findings highlight the importance of geographical topography in determining how species responded to the climate changes that took place in the QTP during the Pleistocene.
On the Reactivity of RSnCl and RSiMe3 {R = 4‐tBu‐2,6‐[P(O)(OiPr)2]2C6H2} towards BF3·OEt2: Competing Lewis Acidities
Authors: Wagner Michael , Lutter Michael , Dietz Christina , Prosenc Marc H. , Jurkschat Klaus 
Published: March 2015

AbstractThe reactions of boron trifluoride with the organostannylene RSnCl {R = 4‐tBu‐2,6‐[P(O)(OiPr)2]2C6H2} and the organosilane RSiMe3 provided the corresponding 1:1 and 1:2 complexes, respectively, through the formation of P=O→B interactions. In the former reaction, even with excess BF3·OEt2, no Sn→B complexation involving the lone electron pair at the tin(II) center was observed. The experimental results are supported by DFT calculations.
In situ synchrotron‐based X‐ray powder diffraction and micro‐Raman study of biomass and residue model compounds at hydrothermal conditions
Authors: Thomas Morgan L. , Butler Ian S. , Kozinski Janusz A. 
Published: March 2015

AbstractThe applications of synchrotron X‐ray powder diffraction (XRPD) and laser micro‐Raman techniques in an examination of the dissolution, transformation, and gasification of pure cellulose and models for biomass residue under hydrothermal conditions in a diamond‐anvil cell are reported. The results contribute to the measurement of in situ time‐resolved profiles of biomass reactions, catalyst stability, and residue formation that occur in aqueous fluids at near‐ and supercritical conditions.