bluuebunny/crossref_metadata_2025_split huggingface dataset:
Factors influencing the electrokinetic injection of oligonucleotides in capillary gel electrophoresis when using laser‐induced fluorescence detection
Authors: Chen Buyun , Chen Guanhua , Bartlett Michael G. 
Published: October 2013

ABSTRACTCapillary gel electrophoresis (CGE) is a powerful tool for the analysis of oligonucleotides owing to its extraordinary resolving power. However, the only feasible injection mode for CGE, electrokinetic injection, can cause bias of the injected amount and thus reproducibility issues for CGE methods. Although the source of the bias in electrokinetic injection for analysis of small molecules by capillary zone electrophoresis has long been identified, there are very few studies on electrokinetic injection issues for biological molecules analyzed by CGE. In this study, we report three issues related to electrokinetic injection for oligonucleotides. First, the relationship between the injection amount and the sample solution resistance is not always linear for oligonucleotides, as has been observed for small molecules. Second, the injecting water prior to an oligonucleotide sample dramatically improves the reproducibility of both the injected amount and resolution through a ‘stacking‐like’ mechanism. Third, optimizing the gel concentration dramatically increases the amount of oligonucleotide that is injected into the column. Copyright © 2013 John Wiley & Sons, Ltd.
The effectiveness of borneol on pharmacokinetics changes of four ginsenosides in Shexiang Baoxin Pill in vivo
Authors: Jiang Peng , Fu Peng , Xiang Li , Wang Shuping , Liu Xiaojun , Yang Ling , Tao Jianfei , Chen Zhongliang , Zhan Changsen , Huang Ximing , Liu Runhui , Zhang Weidong 
Published: October 2013

ABSTRACTShexiang Baoxin Pill (SBP) is a traditional Chinese medicine, widely used for cardiovascular diseases in the clinic. Ginsenosides are important effective components in SBP, but their pharmacokinetic characteristics are still not known. In this paper, we studied the pharmacokinetics of ginsenoside Rb1, Rc, Re and Rg1 in SBP and investigated the effect of borneol on the pharmacokinetic characteristic of ginsenosides based on an Agilent G6410A triple quadrupole LC/MS system. Results showed that the pharmacokinetic parameters of ginsenoside Rb1, Rc, Re and Rg1 in rat plasma after oral administration of SBP are significantly different with oral administration of SBP without Borneolum Syntheticum. Plasma pharmacokinetic profiles after oral administration of ginsenoside Rb1, Rc, Re, Rg1 and co‐administration with borneol at three different ratios (10:1, 1:1 and 1:10 ginsenoside vs borneol, w/w) were also determined. It was demonstrated that borneol can elevate the plasma concentration of ginsenosides after co‐admininstration. Copyright © 2013 John Wiley & Sons, Ltd.
Solvent bar microextraction combined with high‐performance liquid chromatography for preconcentration and determination of pramipexole in biological samples
Authors: Ghasemi Ensieh , Kheradmand Salim , Ghorban Dadrass Orkideh 
Published: October 2013

ABSTRACTA simple, rapid and sensitive analytical method for preconcentration and determination of pramipexole in different biological samples has been developed using solvent bar microextraction (SBME) combined with HPLC‐UV. The target drugs were extracted from 10 mL of basic aqueous sample solution into an organic extracting solvent located inside the pores of a polypropylene hollow fiber, then back‐extracted into an acidified aqueous solution in the lumen of the hollow fiber. In order to obtain high extraction efficiency, the effect of different variables on the extraction efficiency was studied simultaneously using an experimental design. The experimental parameters of SBME were optimized using a Box–Behnken design after a Plackett–Burman screening design. Under the optimized conditions, an enrichment factor up to 96 was achieved and the relative standard deviation of the method was 4.64% (n = 5). The linear range was 0.05–2000 µg/L with a correlation coefficient (r) of 0.987. Finally, the applicability of the proposed method was evaluated by extraction and determination of pramipexole in plasma and urine samples. The results indicated that SBME method has excellent clean‐up and high preconcentration factor and can serve as a simple and sensitive method for analysis of pramipexole in biological samples. Copyright © 2013 John Wiley & Sons, Ltd.
Why Do Members of Disadvantaged Groups Strike Back at Perceived Negativity Towards the In‐group?
Authors: Owuamalam Chuma , Issmer Christian , Zagefka Hanna , Klaßen Matthias , Wagner Ulrich 
Published: October 2013

ABSTRACTAgainst the background of riots in communities across London in 2011, this paper examines the implications of negative meta‐stereotypes on stigmatized group members' reactions towards members of privileged out‐groups within their communities. We hypothesized that concerns over negative opinions that the dominant out‐group is expected to hold of the in‐group (i.e. meta‐stereotypes) would be negatively associated with group members' perceptions of societal fairness and that this relationship would be mediated by members' recall of personal experiences with discrimination. We further hypothesized that views about societal fairness that are challenged in this way would lower an inclination to express discontent with the status quo via normative means while at the same time, increase nonnormative expressions. Results from two surveys (study 1, N = 50; study 2, N = 132) provided support for these hypotheses and are discussed in terms of their meaning for community relations. Copyright © 2013 John Wiley & Sons, Ltd.
Retracted: 1,3,5‐Trihydroxy‐13,13‐dimethyl‐2H‐pyran [7,6‐b] xanthone directly targets heat shock protein 27 in hepatocellular carcinoma
Authors: Fu Wei‐ming , Wang Wei‐mao , Wang Hua , Zhu Xiao , Liang Yan , Kung Hsiang‐fu , Zhang Jin‐fang 
Published: October 2013

AbstractWe previously showed that the small molecule 1,3,5‐trihydroxy‐13,13‐dimethyl‐2H‐pyran [7,6‐b] xanthone (TDP) induces apoptosis in hepatocellular carcinoma (HCC) by suppressing Hsp27 expression, although the mechanism is not fully understood. To investigate the functional association between TDP and Hsp27 protein in HCC, recombinant Hsp27 protein was incubated with TDP at room temperature, and assayed by mass spectrum (MS) and natural electrophoresis. TDP effectively stimulated Hsp27 to form aggregates ex vitro, leading to suppression of its chaperone activity. The aggregates were degraded by the ubiquitin–proteasome (UPS) pathway. TDP directly interacted with Asp17 and Phe55 in chain C of Hsp27 on the basis of bioinformatic prediction. In conclusion, Hsp27 is a direct target of TDP in its anti‐cancer activity, which provides strong support for a clinical application.
Flow Patterns in Mini‐Hydrocyclones with Different Vortex Finder Depths
Authors: He F. , Zhang Y. , Wang J. , Yang Q. , Wang H. , Tan Y. 
Published: October 2013

AbstractTwo‐phase flow patterns in a mini‐hydrocyclone with different insertion depths of the vortex finder were measured by a phase Doppler particle analyzer. The distributions of velocity, concentration, root‐mean‐square velocity, and average diameter of particles were evaluated. A deeper insertion of the vortex finder led to smaller tangential velocity at the cross section near the column cone interface. When the vortex finder insertion depth did not reach the column cone interface, the vortex finder was inserted deeper and the line of zero velocity value migrated more distinctly inward. When the vortex finder insertion depth reached or exceeded the column cone interface, strong turbulence occurred near the vortex finder. The distributions of the axial velocities of particles and root‐mean‐square velocities indicated that circulation flow existed at the bottom part of the mini‐hydrocyclone.
Effect of Carbon Dioxide Chemical Absorption on Bubble Diameter and Interfacial Area
Authors: López A. B. , Gómez‐Díaz D. , La Rubia M. D. , Navaza J. M. 
Published: October 2013

AbstractThe influence of a gas‐liquid chemical reaction on the interfacial area produced in a contactor is analyzed. Two different amines were used to capture carbon dioxide by chemical absorption. The effects of the operation time, the amine used, the concentration interval, and the gas flow rate on typical hydrodynamic parameters used in bubble columns such as the gas holdup and the Sauter mean diameter were investigated. These parameters were used to determine the interfacial area value. Significant influences on the gas‐liquid interfacial area were detected, mainly caused by the reaction rate intensity, the physicochemical properties of the liquid phase, and the gas flow rate fed to the contactor.
2,4,6‐Triarylphosphinines versus 2,4,6‐Triarylpyridines: An Investigation of the Differences in Reactivity between Structurally Related Aromatic Phosphorus and Nitrogen Heterocycles
Authors: Weemers Jarno J. M. , Wiecko Jelena , Pidko Evgeny A. , Weber Manuela , Lutz Martin , Müller Christian 
Published: October 2013

AbstractThe novel atropisomeric pyridine derivative rac‐10 has been synthesized and structurally characterized. In contrast to its phosphorus analogue 3, axially chiral 10 has a considerably lower rotational barrier as estimated by DFT calculations. However, the presence of the two enantiomers could be confirmed by means of chiral analytical HPLC analysis and by protonation experiments with a chiral acid. Compound rac‐10 could be further dehydrogenated by treatment with DDQ to the benzo(h)quinoline derivative rac‐12. This conversion failed for the phosphorus analogue rac‐3. Interestingly, although 2,4,6‐triarylphosphinines undergo facile CH activation with [Cp*IrCl2]2 in the presence of NaOAc, this reaction does not proceed with the corresponding pyridine derivatives. On the other hand, the latter ones can be selectively ortho‐metalated with Pd(OAc)2, leading to acetate‐bridged dimeric species, which could be unambiguously confirmed by means of X‐ray crystal structure analysis. The treatment of phosphinines with Pd(OAc)2 led instead to the formation of the unusual cofacial oxidative coupling products 16 and 17, which consist of a phosphorus‐containing cage structure.
The N‐Terminal Nonapeptide of Cephaibols A and C: A Naturally Occurring Example of Mismatched Helical Screw‐Sense Control
Authors: Orcel Ugo , De Poli Matteo , De Zotti Marta , Clayden Jonathan 
Published: October 2013

AbstractThe N‐terminal nonapeptide domain of the fungal nonribosomal peptide antibiotics cephaibol A and cephaibol C (AcPheAib4LeuIvaGly‐ Aib) is reported to adopt a right‐handed helical conformation in the crystalline state. However, this conformation is at odds with the left‐handed helicity observed in solution in related synthetic oligomers capped with Ac‐L‐PheAib4 fragments. We report the synthesis of four diastereoisomers of the cephaibol N‐terminal nonapeptide, and show by NMR and CD spectroscopy that the peptide containing the chiral amino acids Phe and Leu in the naturally occurring relative configuration exists in solution as an interconverting mixture of helical screw‐sense conformers. In contrast, the nonapeptide containing the unnatural relative configuration at Phe and Leu adopts a single, stable helical screw‐sense, which is left handed when the N‐terminal Phe residue is L and right‐handed when the N‐terminal Phe residue is D.
Stereoselective Synthesis of (3R)‐3‐Alkyl‐4,1‐Benzoxazepine‐2,5‐Diones
Authors: Nisar Bushra , Raza Abdul Rauf , Black David Stc. , Kumar Naresh , Tahir Muhammad Nawaz 
Published: October 2013

ABSTRACTNovel 3‐alkyl‐4,1‐benzoxazepine‐2,5‐diones were synthesized in good ee exploiting the chiral pool methodology, an economical way of asymmetric synthesis. Various anthranilic acids are coupled with different α‐haloacids to afford N‐acylated anthranilic acid intermediates which undergo cyclization to (3R)‐3‐alkyl‐4,1‐benzoxazepines‐2,5‐diones. Chirality 25:865–870, 2013. © 2013 Wiley Periodicals, Inc.
Recovery and Enantioseparation of Chiral Anesthetic Gases with Modified Porous Glasses
Authors: Munkelt Thomas , Küster Christian , Hamel Christof , Enke Dirk , Seidel‐Morgenstern Andreas , Seidel‐Morgenstern Andreas 
Published: October 2013

AbstractPoröses Glas ist aufgrund seiner chemischen und physikalischen Eigenschaften sowie der Möglichkeit von gezielten Oberflächenmodifikationen vielfältig einsetzbar. In dieser Arbeit wird die Synthese und Optimierung von porösen Glaskugeln zur Rückgewinnung und Enantiomerentrennung chiraler Anästhetika beschrieben. Neben der Charakterisierung mittels Stickstoffsorption und Quecksilberintrusion wird das Retentionsverhalten von Desfluran auf nativen Trägern sowie nach Immobilisierung eines chiralen Selektors chromatographisch untersucht.
Metal Organic Frameworks for Natural Gas Storage in Vehicles
Authors: Arnold Lena , Averlant Gauthier , Marx Stefan , Weickert Mathias , Müller Ulrich , Mertel Jonathan , Horch Carsten , Peksa Mikulas , Stallmach Frank 
Published: October 2013

AbstractWith the increasing demand for alternative fuels the storage of natural gas (NG) in adsorbents like metal organic frameworks (MOFs) will become more important. In order to use MOFs as storage media in fuel delivery systems, the optimization of mass and energy transfer of the system is crucial. For rapid NG filling of a tank, molecules need to reach the adsorption sites within a reasonable time while the heat of adsorption should be dissipated to the environment. In this article, mass transfer in shaped bodies of MOFs was determined by permeability measurements and pulsed field gradient (PFG) NMR spectroscopy. The heat dissipation was also experimentally measured and both data sets were used to set up a theoretical density function theory model to predict the behavior of MOFs for NG storage.
Controlling Morphology of Active Layer by Tuning Coplanarity of the Centrality in Acceptor‐Donor‐Acceptor Small Molecules for Photovoltaic Application
Authors: Zhang Pan , Li Chao , Zhao Yue , Li Yaowen , Tu Yingfeng 
Published: October 2013

AbstractA series of acceptor‐donor‐acceptor alternative small molecules were synthesized containing electron‐donating central building moieties of phenothiazine, 2,7‐carbazole and thieno[3,4‐b]thiophene and electron‐accepting moieties of tetrazine on both sides. The various conformations of the central blocks, with the coplanarity in an order of phenothiazine<2,7‐carbazole<thieno[3,4‐b]thiophene, have an obvious influence on the optical, electrochemical property and the crystallinity of small molecule. In addition, the blend films between small molecule and (6,6)‐phenyl‐C61‐butyric acid methyl ester offered signi?cantly various morphologies, changing from uniform surface to interpenetrated networks. As a result, the bulk heterojunction photovoltaic devices based on the three small molecules provided varied performance, and the highest coplanar molecule based device exhibited the best photovoltaic performance.
Dithieno[a,e]pentalene Based Conjugated Polymers: Synthesis and Characterization
Authors: Hu Chao , Zhang Qing 
Published: October 2013

AbstractThe concept of introducing π‐conjugated but anti‐aromatic repeating units into conjugated polymers has been explored. The thermal stability, optical and electrochemical properties of dithieno[a,e]pentalenes (DTP) based polymers have been studied. The effect of introducing electron withdrawing repeating units into DTP based polymer on the physical properties of polymer has also been investigated. The new polymers showed broad absorption in visible and near‐infrared region.
„A German Formula“ – Rezepte für Geheimtinten aus den Archiven der CIA
Authors: Krahl Emanuel , Ducci Matthias 
Published: October 2013

AbstractIm Jahre 2011 hob der damalige CIA‐Direktor Leon Panetta die Vertraulichkeit von Dokumenten auf, die 93 Jahre lang als amerikanisches Staatsgeheimnis eingestuft wurden. Das Konvolut enthält u. a. zahlreiche Rezepturen zur Herstellung unterschiedlicher Geheimtinten für den Einsatz im Nachrichtendienst. Der vorliegende Beitrag greift eine Auswahl der Versuchsvorschriften heraus und beleuchtet die chemischen Hintergründe. Darüber hinaus wird aufgezeigt, dass diese Materialien für den Einsatz im Chemieunterricht hervorragend geeignet sind. Abschließend wird ein Experiment beschrieben, bei dem mit Haushaltsprodukten UV‐Geheimtinte hergestellt wird.
Ultrastructure of cisternal synapses on outer hair cells of the mouse cochlea
Authors: Fuchs Paul Albert , Lehar Mohamed , Hiel Hakim 
Published: October 2013

ABSTRACTC (cisternal) synapses with a near membrane postsynaptic cistern are found on motor neurons and other central neurons, where their functional role is unknown. Similarly structured cisternal synapses mediate cholinergic inhibition of cochlear hair cells via α9α10‐containing ionotropic receptors and associated calcium‐activated (SK2) potassium channels, providing the opportunity to examine the ultrastructure of genetically altered cisternal synapses. Serial section electron microscopy was used to examine efferent synapses of outer hair cells (OHCs) in mice with diminished or enhanced cholinergic inhibition. The contact area of efferent terminals, the appositional area of the postsynaptic cistern, the distance of the cistern from the plasma membrane, and the average width of the cisternal lumen were recorded. The synaptic cisterns of wild‐type OHCs were closely aligned (14‐nm separation) with the hair cell membrane and coextensive with the micrometers‐long synaptic terminals. The cisternal lumen averaged 18 nm so that the cisternal volume was approximately 30% larger than that of the cytoplasmic space between the cistern and the plasma membrane. Synaptic ultrastructure of α9L9′T knockin OHCs (acetylcholine receptor gain of function) were like those of wild‐type littermates except that cisternal volumes were significantly larger. OHCs of SK2 knockout mice had few small efferent terminals. Synaptic cisterns were present, but smaller than those of wild‐type littermates. Taken together, these data suggest that the cistern serves as a sink or buffer to isolate synaptic calcium signals. J. Comp. Neurol. 522:717–729, 2014. © 2013 Wiley Periodicals, Inc.
Derivation of aortic distensibility and pulse wave velocity by image registration with a physics‐based regularisation term
Authors: Barber David C. , Valverde Isra , Shi Yubing , Brown Alistair , Beerbaum Philipp , Rodney Hose D. 
Published: October 2013

SUMMARYAnalysis of the cardiovascular system represents a classical problem in which the solid and fluid phases interact intimately, and so is a rich field of application for state‐of‐the‐art fluid–solid interaction (FSI) analyses. In this paper, we focus on the human aorta. Solution of the full FSI problem requires knowledge of the material properties of the wall and information on vessel support. We show that variation of distensibility along the aorta can be obtained from four‐dimensional image data using image registration. If pressure data at one point in the vessel are available, these can be converted to absolute values. Alternatively, values of pulse wave velocity along the vessel can be obtained. The quality of the extracted data is improved by the incorporation into the registration of a regularisation term based on the one‐dimensional wave equation. The method has been validated using simulated data. For idealised vessels, the accuracy with which the distensibility and wave velocity can be extracted is high (1%–2%). The method is applied to six clinical datasets from patients with mild coarctation, for which it is shown that wave velocity along the aorta is relatively constant. Copyright © 2013 John Wiley & Sons, Ltd.
Structure, Stoichiometry, and Electrochemical Performance of Li2CoTi3O8 as an Anode Material for Lithium‐Ion Batteries
Authors: Wang Jie , Zhao Hailei , Shen Yongna , Du Zhihong , Chen Xiaomin , Xia Qing 
Published: October 2013

AbstractLi2CoTi3O8 powder has been synthesized by a simple citric nitrate method and was evaluated as an anode material for lithium‐ion batteries. The X‐ray diffraction (XRD) Rietveld refinement and X‐ray photoelectron spectroscopy (XPS) measurements indicate the existence of Ti‐site deficiency and a mixed‐valence state of Co ions in the Li2CoTi3O8 structure. The refined site‐occupation result gave a nonstoichiometric chemical formula of Li2CoTi2.682O8, which corresponds to a theoretical specific capacity of 322 mA h g−1, which is much higher than that of the stoichiometric material (233 mA h g−1). The synthesized Li2CoTi2.682O8 material exhibits high reversible capacity (ca. 320 mA h g−1), and excellent cycling stability and rate capability. A specific capacity of about 240 and 160 mA h g−1 can be achieved at 2 and 6 A g−1, respectively, by the Li2CoTi2.682O8 material. First‐principles calculation demonstrates that Ti‐site deficiency decreases the bandgap and thus facilitates the electron conduction.
Metal Segregation in Bimetallic CoPd Carbide Carbonyl Clusters: Synthesis, Structure, Reactivity and Electrochemistry of [H6−nCo20Pd16C4(CO)48]n− (n=3–6)
Authors: Ciabatti Iacopo , Fabrizi de Biani Fabrizia , Femoni Cristina , Iapalucci Maria Carmela , Longoni Giuliano , Zacchini Stefano 
Published: October 2013

AbstractNanometric CoPd bimetallic [H6−nCo20Pd16C4(CO)48]n− (n=3–6) tetracarbide carbonyl clusters have been prepared by redox condensation of [Co6C(CO)15]2− with [PdCl2(Et2S)2]. The crystal structures of both the dihydride tetra‐anion and monohydride penta‐anion have been determined as their [NEt4]4[H2Co20Pd16C4(CO)48]⋅4 CH3COCH3 and [NMe3(CH2Ph)][NMe4]4[HCo20Pd16C4(CO)48]⋅5 CH3COCH3 salts, respectively. The two species are isostructural and their structures display a perfect segregation of the two metals. They are composed of a cubic close‐packed (ccp) Pd16 core stabilised on its surface by four {Co5C(CO)12} organometallic fragments. Their polyhydride nature has been corroborated by the study of their reactions with acids and bases, and confirmed by electrochemical studies. In addition, the reactions of [H2Co20Pd16C4(CO)48]4− with Na/naphthalene and PPh3/CO allowed the isolation of other lower nuclearity homoleptic and heteroleptic clusters, that is, [H6−nCo16Pd2C3(CO)28]n− (n=5, 6), [Co4Pd2C(CO)11(PPh3)2], [Co2Pd5C(CO)8(PPh3)5], and [Co4Pd4C2(PPh3)4(CO)10Cl]−. [H6−nCo16Pd2C3(CO)28]n− (n=5, 6) represent the first homoleptic metal–carbonyl clusters containing three interstitial carbide atoms.
Efficient identity‐based key encapsulation scheme with wildcards for email systems
Authors: Yang Yang 
Published: October 2013

SUMMARYIdentity‐based key encapsulation scheme with wildcards (WIB‐KEM) is very useful in email systems for confidential communication, as it enables the effective encryption of email to a range of users simultaneously whose identities match a certain pattern. In this paper, I propose a WIB‐KEM scheme achieving simultaneously high efficiency and security level. Our scheme achieves the low computational cost because during the decryption phase the bilinear pairing operation of decryption is constant. Moreover, the private key size shrinks as the identity depth increases. I further prove its adaptive chosen ciphertext security under decisional bilinear Diffie–Hellman assumption in standard model. The scheme not only can meet security demands but is also efficient in terms of computation and communication. Our scheme is tested on a modern station, and the experimental results demonstrate its suitability for large‐scale email systems. Copyright © 2013 John Wiley & Sons, Ltd.