bluuebunny/crossref_metadata_2025 huggingface dataset:
Concise Synthesis of Well‐Defined Linear and Branched Oligothiophenes with Nickel‐Catalyzed Regiocontrolled Cross‐Coupling of 3‐Substituted Thiophenes by Catalytically Generated Magnesium Amide
Authors: Tanaka Shota , Tanaka Daiki , Tatsuta Go , Murakami Kohei , Tamba Shunsuke , Sugie Atsushi , Mori Atsunori
Published: December 2012

The synthesis of linear and branched oligothiophenes of well‐defined structures is performed with regioselective deprotonation of 3‐substituted thiophenes and nickel‐catalyzed cross‐coupling of the thus formed metalated species with a bromothiophene. The reaction of 3‐hexylthiophene with EtMgCl and 2,2,6,6‐tetramethylpiperidine (TMP‐H, 10 mol %) induces the metalation selectively at the 5‐position by use of the catalytically generated hindered magnesium amide (TMPMgCl) and the subsequent reaction of a 2‐halo‐3‐hexylthiophene (bromide or chloride) in the presence of a nickel catalyst affords a head‐to‐tail (HT)‐type dimer. By repeating the same sequence, the linear oligothiophene up to a 4‐mer is synthesized in good yield. The reaction of 3‐hexylthiophene with 2,3‐dibromothiophene also takes place to afford a branched oligothiophene 3‐mer in quantitative yield. The obtained 3‐mer is also metalated at the sterically less‐hindered position in a regioselective manner furnishing a 7‐mer in >99 % yield after a further coupling reaction with 2,3‐dibromothiophene. These dendrimers react with several multifunctionalized organic electrophiles, leading to a variety of branched oligothiophenes.
Comparison of Two‐Fluid and Discrete Particle Modeling of Dense Gas‐Particle Flows in Gas‐Fluidized Beds
Authors: Wang Junwu , van der Hoef Martin A. , Kuipers J. A. M.
Published: December 2012

Both two‐fluid models embedding the kinetic theory of granular flow for particulate phase stress (TFM) and discrete particle models (DPM) are widely used for the numerical simulation of gas fluidization. In this study, a detailed comparison between results obtained from both TFM and DPM is reported, including axial and radial solid concentration profiles, solids circulation patterns, pressure drop and its standard deviation and granular temperature. It was shown that good agreement can be obtained even in cases of low restitution coefficient, which suggests the possible applicability of kinetic theory of granular flow beyond its nominal range of validity and clearly indicates that the continuum treatment of the solids phase in TFM provides a good approximation of its discrete nature.
Novel, Rotary Oscillated, Scalable Single‐Use Bioreactor Technology for the Cultivation of Animal Cells
Authors: Kauling Jörg , Brod Helmut , Jenne Marc , Waldhelm Annette , Langer Uwe , Bödeker Berthold
Published: December 2012

The BaySHAKE® single‐use bioreactor is based on the motion principle of rotary oscillation of a polyhedral container. This fundamental working principle facilitates mixing and oxygen transfer to animal cell cultures in a simple, robust and cost‐efficient single‐use system without internal moving parts. In‐depth hydrodynamic characterization shows that the bioreactor provides mixing and oxygen transfer in a low‐shear environment over a range of scales up to several cubic meters. A biological comparison of novel single‐use technology in scales from 50 to 1000 L with the re‐usable standard deep‐tank technology in scales from 10 to 200 L confirms the technical feasibility and shows good biological equivalence for the production of monoclonal antibodies by CHO cells.
Herstellung moderner Grippeimpfstoffe
Authors: Genzel Yvonne , Frensing Timo , Reichl Udo
Published: December 2012

Noch immer werden 95 % der verfügbaren Grippeimpfstoffdosen mit Hilfe von Hühnereiern hergestellt. Spätestens seit der H1N1‐Influenza‐Pandemie von 2009 ist vielen Menschen jedoch bewusst geworden, dass es im Ernstfall schwierig sein kann, Impfstoffe rechtzeitig und in ausreichender Menge bereitzustellen. Insbesondere ist es wichtig, alternative Herstellungsverfahren weiter zu verbessern oder neue Methoden zu entwickeln. Die hier vorgestellten zellkulturbasierten Prozesse stellen eine vielversprechende Möglichkeit dar, skalierbare und robuste Produktionsverfahren zu etablieren. Es ist davon auszugehen, dass das volle Potential dieser Prozesse bei weitem noch nicht ausgeschöpft ist und durch weitere verfahrenstechnische Maßnahmen, vor allem aber auch durch eine gezielte Optimierung der biologischen Systeme, erhebliche Ausbeutesteigerungen und Produktverbesserungen möglich sind.
Iron(II) α‐Aminopyridine Complexes and Their Catalytic Activity in Oxidation Reactions: A Comparative Study of Activity and Ligand Decomposition
Authors: Lenze Matthew , Martin Erin T. , Rath Nigam P. , Bauer Eike B.
Published: December 2012

New well‐defined FeII complexes bearing bi‐ and tridentate α‐aminopyridine ligands were synthesized, and their catalytic activity in the oxidation of hydrocarbons and alcohols utilizing peroxide oxidants was investigated. The tridendate bis(picolyl)amine ligand 6 and its benzylated analogue 7 were converted into complexes [FeII(6)2]OTf2 (96 %, X‐ray; OTf=CF3SO3−) and [FeII(7)2]OTf2 (90 %). The bidentate aminopyridine ligand 8 was converted into [FeII(8)2(OTf)2] (93 %, X‐ray). The new complexes are catalytically active in the oxidation of secondary alcohols and benzylic methylene groups to the corresponding ketones, of toluene to benzaldehyde, and of cyclohexene to cyclohexene oxide (3 mol % catalyst, tBuOOH (4 equiv), RT, 2–6 h, 28 to 85 % yield of isolated product). The catalytic oxidation of cyclohexane with ROOH (R=H, tBu) to an alcohol/ketone mixture with low ratio revealed that these oxidations follow largely a radical mechanism, except when [FeII(6)2]OTf2 was employed and H2O2 was added slowly. Together with known bi‐ and tetradendate iron complexes, a comparative study showed slight reactivity differences for the newly prepared complexes, with the highest observed for [FeII(6)2]OTf2 and [FeII(7)2]OTf2. The reaction of the new complexes with peroxides was followed over time by UV/Visible spectroscopy; this revealed a fast reaction between the two reactants within minutes. Ligand‐decomposition pathways were investigated, and revealed that the NCH2 units of the complexes are rapidly oxidized to the corresponding amides NCO. The iron complex [FeII(6)2]OTf2 showed no decrease in catalytic activity and a moderate decrease in selectivity when first subjected to oxidative conditions similar to those employed in catalysis. Thus, oxidative ligand deterioration had a marginal effect on the catalytic activity of the iron complex [FeII(6)2]OTf2.
A VLP‐based vaccine against interleukin‐1α protects mice from atherosclerosis
Authors: Tissot Alain C. , Spohn Gunther , Jennings Gary T. , Shamshiev Abdijapar , Kurrer Michael O. , Windak Renata , Meier Marco , Viesti Miriam , Hersberger Martin , Kündig Thomas M. , Ricci Romeo , Bachmann Martin F.
Published: December 2012

Interleukin (IL)‐1α is a potent proinflammatory cytokine that has been implicated in the development of atherosclerosis. We investigated whether a vaccine inducing IL‐1α neutralizing antibodies could interfere with disease progression in a murine model of atherosclerosis. We immunized Apolipoprothin E (ApoE)‐deficient mice with a vaccine (IL‐1α‐C‐Qβ) consisting of full‐length, native IL‐1α chemically conjugated to virus‐like particles derived from the bacteriophage Qβ. ApoE−/− mice were administered six injections of IL‐1α‐C‐Qβ or nonconjugated Qβ over a period of 160 days while being maintained on a western diet. Atherosclerosis was measured in the descending aorta and in cross‐sections at the aortic root. Macrophage infiltration in the aorta was measured using CD68. Expression levels of VCAM‐1, ICAM‐1, and MCP‐1 were quantified by RT‐PCR. Immunization against IL‐1α reduced plaque progression in the descending aorta by 50% and at the aortic root by 37%. Macrophage infiltration in the aorta was reduced by 22%. Inflammation was also reduced in the adventitia, with a decrease of 54% in peri‐aortic infiltrate score and reduced expression levels of VCAM‐1 and ICAM‐1. Active immunization targeting IL‐1α reduced both the inflammatory reaction in the plaque as well as plaque progression. In summary, vaccination against IL‐1α protected ApoE−/− mice against disease, suggesting that this may be a potential treatment option for atherosclerosis.
Synthesis of Chalcogenidoimidodiphosphinato–RhI Complexes and DFT Investigation of Their Catalytic Activation in Olefin Hydroformylation
Authors: Grigoropoulos Alexios , Maganas Dimitrios , Symeonidis Dimitrios , Giastas Petros , Cowley Andrew R. , Kyritsis Panayotis , Pneumatikakis Georgios
Published: December 2012

The synthesis and spectroscopic characterization of [Rh{R2P(S)NP(S)R2‐S,S′}(cod)] [cod = 1,5‐cyclooctadiene; R = Ph (1), iPr (4)], [Rh{Ph2P(S)NP(S)Ph2‐S,S′}(CO)2] (2) and [Rh{Ph2P(S)NP(S)Ph2‐S,S′}(CO)(PPh3)] (3) is described. The crystal structures of complexes 1 and 3 are also presented. The synthesized RhI complexes are essentially not catalytically active against olefin hydroformylation, in contrast to the previously reported complex [Rh{Ph2P(O)NPPh2‐P,O}(CO)(PPh3)] (6). Differences in the catalytic activity were interpreted with the aid of a well‐defined DFT‐based protocol involving relativistic effects and dispersion correction. The steric and electronic effects of the RhI coordination environment with respect to their activation by H2 are discussed. The results demonstrate that the presence of the more electronegative oxygen atom in the RhI coordination sphere polarizes the H–H bond and promotes its heterolytic cleavage, thereby leading to the formation of a RhI–monohydride complex in which the oxygen atom of the ligand is protonated.
Two Types of Polyoxometalates Based on Circular P8W48 Cluster Units and Different Inclusions of Tetralanthanide and Octamanganese Centers
Authors: Huang Ling , Cheng Lin , Fang Wei‐Hui , Wang Sa‐Sa , Yang Guo‐Yu
Published: December 2012

Two types of new polyoxometalates (POMs) based on circular P8W48 clusters with different tetralanthanide (Ln) clusters and octamanganese centers, [K(H2O)2]4[K4(μ‐H2O)4(H2O)4]2{[Ln2(μ‐OH)4(H2O)x]2(H24P8W48O184)}·yH2O [Ln = Nd (1), Sm (2), Tb (3)] and [K(H2O)2]4[K4(μ‐H2O)8]2[K(H2O)]8{[Mn8(H2O)16](H4P8W48O184)}·36H2O (4) have been synthesized under hydrothermal conditions and characterized by single‐crystal X‐ray diffraction, elemental analysis, IR spectroscopy, thermogravimetry (TG), and powder XRD. Compounds 1–3 are the first series of Ln‐containing P8W48‐based POMs that use P2W12O4814– as the precursor; previously known P8W48‐based POMs used P8W48O18440– as the precursor. In 4, eight manganese ions were incorporated. Owing to the different radii of the Ln and Mn ions, the four large Ln ions are divided into two {Ln2} clusters located on two sides of the cavity of the P8W48 wheel in 1–3, but the eight small manganese ions in 4 only bond to the inside of the P8W48 wheel and do not form manganese clusters. The magnetic properties of 3 are discussed.
Trilacunary Keggin‐Type POMs as Versatile Building Blocks for Lanthanoid Silicotungstates
Authors: Ni Lubin , Spingler Bernhard , Weyeneth Stephen , Patzke Greta R.
Published: December 2012

Three new lanthanoid‐substituted polyoxotungstates based on open Wells–Dawson fragments {[Ln2(H2O)7SiW18O66]10– [Ln = EuIII (Eu‐1 and Eu‐2), TbIII (Tb‐1)]} and a new sandwich‐type polyoxometalate constituted of Keggin‐type monolacunary anions {[Eu(α‐SiW11O39)2]13– (Eu‐3)} were obtained from the trilacunary Keggin POM Na10[SiW9O34]·23 H2O and lanthanoid salts as precursors. All compounds were comprehensively characterized by inductively coupled plasma (ICP) and thermogravimetric analyses and by FT‐IR and UV/Vis spectroscopy, as well as by powder X‐ray diffraction (PXRD) and single‐crystal X‐ray diffraction. Eu‐1 and Tb‐1 exhibit 3D architectures of dimeric [Ln2(H2O)7SiW18O66]10– units connected through LnIII linkers, whereas Eu‐2 displays a 2D sheet‐like framework. Eu‐3 exists in two enantiomeric forms, due to the C2 symmetry of the central square‐antiprismatic EuO8 polyhedron. The structure‐directing influence of the Ln cations on the emerging POM architectures is investigated in detail. Photoluminescence of Eu‐1, Eu‐2, Eu‐3 and Tb‐1 can be ascribed to the characteristic emissions of the EuIII and TbIII cations, respectively. The electrochemical properties of all compounds were investigated by cyclic voltammetry in sodium acetate buffer solution as supporting electrolyte. The magnetic susceptibility of Tb‐1 was studied in the temperature range between 5 and 300 K and indicated paramagnetic behavior.
Hydroxyl‐modified cationic lipids with a carbamate linkage as gene delivery vehicles
Authors: Qiao Weihong , Zhou Min
Published: December 2012

We have developed four hydroxyl‐modified cationic lipids with a carbamate linkage as delivery of DNA to the cervix cells. A formulation with cationic lipids and 1,2‐Dioleoyl‐sn‐glycero‐3‐phosphoethanolamine at a molar ratio of 1:1, liposomes 1, 2, 3, and 4 were prepared by conventional thin film evaporation and ultrasonic method. Size and Zeta potential of liposome/DNA complexes were measured at different mass ratios, which were 1/1, 2/1, 3/1, 4/1, 6/1, and 8/1, respectively. Delivery of DNA to Hela cells by the liposomes was evaluated by measuring the transfection efficiency of liposome/DNA complexes. The cytotoxicity was investigated at the ratios above. Gene transfection efficiency of liposomes 1, 2, and 3‐DNA complexes was approximately equal to that of Lipo2000–DNA complex, and a lower cytotoxicity compared with Lipo2000. The largest particle‐size occurred at the break point from negative Zeta potential to positive Zeta potential. The biggest size of liposomes 1, 2, 3, and 4 was 1091, 760.5, 1584, and 436.5 nm, respectively. On head group, the length of carbon chain (lipo 2) could enhance transfection efficiency, while the hydroxy increase (lipo 3) could weaken a little. Moreover, the longer lipophilic tail (lipo 4) could evidently cut down the transfection efficiency.

Practical applications: The findings of the present study will be useful in biomedical applications for delivery of DNA to the cervix. Cationic lipid gene vectors in the condition of carbamate as connection bond and hydroxyalkyl group as head group may improve the gene therapy transfection efficiency and lower cytotoxicity. Research on high transfection efficiency and low toxic targeting gene vector will provide theoretical guidance and show practical significance for the development of promising gene delivery vehicles.
Heterogeneous Photoinduced Homolytic Aromatic Substitution of Electron‐Rich Arenes with Perfluoroalkyl Groups in Water and Aqueous Media – A Radical‐Ion Reaction
Authors: Barata‐Vallejo Sebastián , Flesia Marina Martín , Lantaño Beatriz , Argüello Juan E. , Peñéñory Alicia B. , Postigo Al
Published: December 2012

The photoinduced electron transfer (PET) substitution reaction of electron‐rich aromatic nuclei with perfluoroalkyl Rf groups was carried out in water or aqueous mixtures to render substitution products resulting from replacement of aromatic H atoms with the Rf moiety in good yields (57–88 %). Some mechanistic aspects are discussed, supporting the notion of a PET reaction leading to a classical radical homolytic aromatic substitution (HAS) followed by an electron transfer (ET) and then a proton transfer (PT) sequence. A radical mechanism superimposed on a redox process is proposed to account for product formation. Evidence for the radical cation species (as an initiation event) generated from electron‐rich arenes in the presence of perfluoroalkyl halides is provided by the UV/Vis transient spectra obtained by Nanosecond Laser Flash Photolysis techniques.
FeCl3‐Mediated Arylation of α‐Hydroxyphosphonates with Unactivated Arenes: Pseudo‐Umpolung in Allylic Phosphonates
Authors: Pallikonda Gangaram , Chakravarty Manab
Published: December 2012

An FeCl3‐mediated regio‐ and stereoselective Friedel–Crafts‐type arylation of α‐hydroxy phosphonates with unactivated arenes has been developed in which the unstable allylphosphonate cations generated are stabilized by extended conjugation. The approach provides a simple, efficient and economic approach to highly demanding stereoselective γ‐aryl‐substituted vinylphosphonates and dialkyl (diarylmethyl)phosphonates with good regioselectivity. These reactions proceed under mild conditions and proceed in the absence of any additional solvent.
A new design for efficient dielectrophoretic separation of cells in a microdevice
Authors: Jubery Talukder Z. , Dutta Prashanta
Published: December 2012

Effectiveness of a continuous biological cell separation device can be improved significantly by increasing the distance among different types of cells. To achieve this, most of the recent dielectrophoresis based continuous separation devices implement differential forces on cells either along the transverse direction or the vertical direction with respect to the bulk fluid flow motion. However, interparticle distance can be increased further by implementing forces along both transverse and vertical planes. In this article, a design for a microfluidic platform has been proposed where a new electrode configuration is identified to implement symmetric forces in both vertical and transverse directions. A numerical model, which considers presence of particles in the electric field and flow field, shows a much higher interparticle distance between red blood cells and plasmodium falciparum infected red blood cells in such a device than that in a conventional separation device. This configuration also reduces the possibility of particle trapping on the electrodes, which is a major bottleneck of dielectrophoresis.
New Sulfonated PBIs for PEMFC Application
Authors: Villa D. C. , Angioni S. , Quartarone E. , Righetti P. P. , Mustarelli P.
Published: December 2012

Polybenzimidazole (PBI) is one of the polymers of choice to replace Nafion® in polymer fuel cells working at high temperature. In order to improve the membrane electrical properties, several monomer modifications are proposed, including sulfonation which, however, is not generally uniform and complete. By using a proper aryloxy‐based spacer, we reported here a facile synthesis procedure which allowed us to obtain co‐monomers with 100% mono‐ and di‐sulfonation. Preliminary conductivity measurements showed that mono‐sulfonation allowed to increase of one order of magnitude the proton conductivity at high doping level with respect to pyridine‐based PBI, so reaching values around 0.1 S cm–1 at 120 °C and 50% RH. Di‐sulfonation is efficient only at lower doping levels, where it allows a further 2–3 times increase of the conductivity. These materials are promising as membranes for polymer fuel cells.
Permeability and Diffusivity Measurements on Polymer Electrolyte Membranes
Authors: Arena F. , Mitzel J. , Hempelmann R.
Published: December 2012

An essential material property directly influencing the long‐life capacity of hydrogen‐polymer electrolyte membrane fuel cells (H2‐PEMFCs) systems at elevated temperatures (>80 °C) is the permeability of the PEM material toward gases. The membrane permeability with respect to hydrogen and oxygen is responsible for a decrease of fuel cell efficiency and life‐time. Furthermore permeating oxygen is suspected to form membrane degrading O‐radical species. In view of the importance of gas permeability for further PEM R&D activities we present a test bench for the experimental determination of gas diffusivities and permeabilities for such polymeric materials. The advantages of a direct coupling of the permeation measurement cell with a gas chromatograph as analyzer are outlined. Hydrogen and oxygen diffusivities as well as permeabilities of prospective new materials such as cross‐linked SPEEK are determined at different temperatures and are compared to state‐of‐the‐art PFSA material. A significantly lower permeability regarding hydrogen and oxygen was determined for cross‐linked SPEEK materials. In addition the influence of the hydro‐thermal history of PFSA materials, postulated by G. Alberti, on membrane diffusivity was studied.
Does seaweed offer a solution for bioenergy with biological carbon capture and storage?
Authors: Hughes Adam D. , Black Kenny D. , Campbell Iona , Davidson Keith , Kelly Maeve S. , Stanley Michael S.
Published: December 2012

The concept of combining bioenergy with carbon capture and storage (BECCS) has been identified as one mechanism to achieve energy production with a net negative atmospheric carbon emission. Conventional geological carbon capture and storage involves large capital outlay and recurring expense. Therefore there is increased interest in coupling biological carbon capture and sequestration with biomass production. Systems such as low‐input high‐diversity native grasslands and biochar production have been heralded as carbon negative biofuels. Another potential production system for bioenergy with biological carbon capture and storage (BEBCCS) is the large‐scale cultivation of seaweed (macroalgae) for biofuels. Marine biofuels offer considerable advantages over terrestrial first‐generation biofuels in terms of their low land use, fresh water and fertilizer requirements. In addition, they also offer considerable potential in the field of BEBCCS. Macroalgae rapidly accumulate biomass and as part of this process, a significant proportion (estimates range up to 60%) of the carbon they fix photosynthetically is released into the water. A proportion of this released dissolved organic carbon (DOC) is highly labile and enters the bacterial loop and is rapidly remineralized back to CO2. However, a proportion is known to be resistant to biological degradation and enters the refractory DOC pool. The marine DOC pool is the largest organic carbon pool on the planet and the refractory component is known to have a turnover period of 100s‐1000s years. The release of refractory DOC from macroalgae combined with biofuel production offers the potential for large scale carbon negative fuel production. © 2012 Society of Chemical Industry and John Wiley & Sons, Ltd
Characterizing CO2 storage reservoirs and shallow overburden for above‐zone monitoring in Texas Gulf Coast EOR fields
Authors: Zahid Khandaker M. , Hosseini Seyyed A. , Nuñez‐López Vanessa , Hovorka Susan D.
Published: December 2012

Enhanced oil recovery (EOR) through carbon dioxide (CO2) injection provides an excellent opportunity for commercial sequestration of anthropogenic CO2. A fluvio‐deltaic, deep‐seated salt dome and a strand‐plain, roll‐over anticline from the Gulf Coast region are currently under investigation for the design and implementation of monitoring, verification, and accounting (MVA) plans, in coordination with the commercial surveillance of independent, large‐volume (>1 million ton/year) CO2‐EOR operations. Characterization with wireline logs demonstrates the vertical extent and areal continuity of reservoir sands and geometries of faults that offset the reservoir. To develop the monitoring plan, we focused on several elements: (i) characterization of the zones above the confining unit for above‐zone pressure monitoring, (ii) collection and development of input data for ‘quick‐look’ dynamic modeling of CO2 plume extent and pressure elevation, and (iii) identifying intersections of faults with wellbores in intervals above the regional confining unit for thermal monitoring. Other uncertainties addressed during characterization are the upper extent of faults and the juxtaposition of layers to assess the potential for cross‐fault fluid migration. Successful use of such techniques for MVA, based on uniting elements of existing regulatory monitoring expectations, would lead to the establishment of commercial best practices for effective and rapid characterization of EOR sites in the Gulf Coast region. © 2012 Society of Chemical Industry and John Wiley & Sons, Ltd
Synthesis of Enantiomerically Pure Isoxazolidine Monomers for the Preparation of β3‐Oligopeptides by Iterative α‐Keto AcidHydroxylamine (KAHA) Ligations
Authors: Chiang Ying‐Ling , Russak Justin A. , Carrillo Nancy , Bode Jeffrey W.
Published: December 2012

A versatile method for the synthesis of enantiomerically pure isoxazolidine monomers for the synthesis of β3‐oligopeptides via α‐keto acidhydroxylamine (KAHA) ligation is presented. This one‐pot synthetic method utilizes in situ generated nitrones bearing gulose‐derived chiral auxiliaries for the asymmetric 1,3‐dipolar cycloaddition with methyl 2‐methoxyacrylate. The resulting enantiomerically pure isoxazolidine monomers bearing diverse side chains (proteinogenic and non‐proteinogenic) can be synthesized in either configuration (like‐ and unlike‐configured). The scalable and enantioselective synthesis of the isoxazolidine monomers enables the use of the synthesis of β3‐oligopeptides via iterative α‐keto acidhydroxylamine (KAHA) ligation.
2‐Amino‐1,2,3,6‐tetrahydro‐6‐oxocyclopenta[c]fluorene‐2‐carboxylic Acid (FlAib), a Completely Rigidified, Fluoren‐9‐one‐Based α‐Amino Acid
Authors: Wright Karen , Alvarez Antonio Blanco , Crisma Marco , Toffoletti Antonio , Formaggio Fernando , Toniolo Claudio
Published: December 2012

The synthesis, optical resolution, determination of absolute configuration and conformational preference, and spectroscopic characteristics of terminally protected (blocked) derivatives and short peptides of 2‐amino‐1,2,3,6‐tetrahydro‐6‐oxocyclopenta[c]fluorene‐2‐carboxylic acid (FlAib), a novel, rigid, chiral, cyclized Cα,α‐disubstituted glycine are described.
Dynamic Phenomena in Self‐Complementary {2}‐Metallocryptates Probed by Solution 133Cs‐NMR. New Insights into Ion Pairing Processes: X‐Ray Structure and Solid‐State NMR Spectra of a Meandering Species
Authors: Maid Harald , Heinemann Frank W. , Scheurer Andreas , Mooren Nicolai , Saalfrank Rolf W. , Bauer Walter
Published: December 2012

Two self‐complementary {2}‐metallocryptates, differing in methyl and phenyl substituents, respectively, have been studied by X‐ray analysis, and solid‐state and solution NMR. Mixed Mg/Cs metal methyl complex 2 is a linear polymer in the solid state. The two different Cs sites are confirmed by 133Cs‐solid‐state NMR. By contrast, the analog mixed Mg/Cs metal phenyl complex 4 is a meandering polymer as shown by an actual X‐ray analysis. The four non‐equivalent Cs‐sites in 4 are reflected in the solid‐state NMR spectra. Solution 133Cs‐NMR spectra of 4 reveal two independent dynamic processes: a fast exchange of Cs within contact ion‐pairs and solvent‐separated ion‐pairs (CIP, SSIP), and a slower exchange of ‘inside’ endo Cs, surrounded by three ligands, and ‘outside’ exo Cs involved in the CIP/SSIP equilibrium. Complete line‐shape analysis of variable‐temperature 133Cs‐NMR spectra of 4 yield kinetic parameters of magnified image
=10.8 kcal/mol for the fast SSIP‐CIP exchange and =13.2 kcal/mol for the slower endo/exo exchange of Cs. DOSY‐NMR Measurements confirm the monomeric nature of 4 in solution.
Enantioselective Michael Addition of the 2‐(1‐Ethylpropoxy)acetaldehyde to N‐[(1Z)‐2‐Nitroethenyl]acetamide – Optimization of the Key Step in the Organocatalytic Oseltamivir Synthesis
Authors: Hajzer Viktória , Latika Attila , Durmis Július , Šebesta Radovan
Published: December 2012

Organocatalytic Michael addition of alkoxyacetaldehyde 1 to N‐protected 2‐nitroethene‐1‐amine 2 (Scheme 2) is a key step in the synthesis of an important antiviral agent, oseltamivir. Screening of a large array of structurally diverse acids as potential promoters led to the identification of several useful acidic additives for this reaction (Tables 1–4). Also other reaction parameters were investigated with the aim of improving the diastereoselectivity of the Michael addition, while maintaining high enantiomer purity and yield (Tables 5 and 6).
Synthesis of AzaaromaticBorane Intramolecular Complexes by Palladium‐Catalyzed Reaction of Azaaromatic Halides with Alkynyl(triaryl)borates
Authors: Ishida Naoki , Narumi Mizuna , Murakami Masahiro
Published: December 2012

A diversity‐oriented method to synthesize (E)‐azastilbenes having an intramolecular BN coordination bond from alkynyl(triaryl)borates and azaaromatic halides is described. The obtained π‐conjugated compounds exhibit an intense blue fluorescence and a high electron affinity, indicating their potential to be used as n‐type light‐emitting materials.
Directed MetalationCross‐Coupling Strategies. Total Syntheses of the Alleged and the Revised Phenanthrene Natural Product Gymnopusin
Authors: Wang Xin , Fu Jian‐min , Snieckus Victor
Published: December 2012

The total synthesis of gymnopusin (2) is described. The originally assigned structure for gymnopusin 1a was found to be incorrect by total synthesis using the Directed ortho‐Metalation (DoM)Cross‐CouplingDirected remote Metalation (DreM) sequence, a demonstrable key strategy for the regioselective construction of the 9‐phenanthrol core. The revised structure of gymnopusin (2) was confirmed by synthesis by adopting the same strategy but involving a key remote anionic Fries‐rearrangement step. Both routes highlight methodologies and concepts which may be of value in the regiocontrolled synthesis of phenanthrenoids specifically and in complex polycyclic aromatics in general.
Polyurethanes containing zwitterionic sulfobetaines and their molecular chain rearrangement in water
Authors: Cao Jun , Yang Mou , Lu Aijing , Zhai Shuying , Chen Yuanwei , Luo Xianglin
Published: December 2012

Novel polyurethanes with zwitterionic sulfobetaines, termed PUR‐APS, were designed and synthesized by chain‐extension of biodegradable poly(ε‐caprolactone) containing N,N′‐bis (2‐hydroxyethyl) methylamine ammonium propane sulfonate (PCL‐APS) with hexamethylene diisocyanate (HDI). The bulk properties of polymers were characterized by nuclear magnetic resonance spectrum (NMR), Fourier transform infrared spectroscopy (FTIR), gel permeation chromatograph (GPC), and differential scanning calorimetry (DSC). Results showed that the polymers were successfully synthesized. Water contact angles (WCAs) and X‐ray photoelectron spectroscopy (XPS) revealed that molecular chains of the polymers rearranged after soaking in water. The amount of protein adsorption, determined by bicinchoninic acid (BCA) assay, was less than 300 ng/cm2 and decreased after hydration. The blood compatibility of the polymers was evaluated by the degree of hemolytic and activated partial thromboplastic time (APTT) and prothrombin time (PT). Results indicated that PUR‐APS polymers had good blood compatibility. Therefore, polyurethanes containing sulfobetaines have a great potential for biomedical application. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 101A: 909–918, 2013.
In‐vivo behavior of Si‐hydroxyapatite/polycaprolactone/DMB scaffolds fabricated by 3D printing
Authors: Meseguer‐Olmo Luis , Vicente‐Ortega Vicente , Alcaraz‐Baños Miguel , Calvo‐Guirado José Luis , Vallet‐Regí María , Arcos Daniel , Baeza Alejandro
Published: December 2012

Scaffolds made of polycaprolactone and nanocrystalline silicon‐substituted hydroxyapatite have been fabricated by 3D printing rapid prototyping technique. To asses that the scaffolds fulfill the requirements to be considered for bone grafting applications, they were implanted in New Zealand rabbits. Histological and radiological studies have demonstrated that the scaffolds implanted in bone exhibited an excellent osteointegration without the interposition of fibrous tissue between bone and implants and without immune response after 4 months of implantation. In addition, we have evaluated the possibility of improving the scaffolds efficiency by incorporating demineralized bone matrix during the preparation by 3D printing. When demineralized bone matrix (DBM) is incorporated, the efficacy of the scaffolds is enhanced, as new bone formation occurs not only in the peripheral portions of the scaffolds but also within its pores after 4 months of implantation. This enhanced performance can be explained in terms of the osteoinductive properties of the DBM in the scaffolds, which have been assessed through the new bone tissue formation when the scaffolds are ectopically implanted. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
2013 M&A Update
Authors: Schmid Alexandra S. , Sánchez Carol M. , Goldberg Stephen R.
Published: December 2012

The authors give an update on the current M&A climate, with a special focus on cross‐border M&A considerations for middle‐market firms. © 2013 Wiley Periodicals, Inc.
Snapping Up Euro Bargains with Trapped Cash
Authors: Le Guyader Louis P.
Published: December 2012

American corporations now hold well over $1.7 trillion in cash‐a record‐breaking level. But much of it is held overseas to avoid higher U.S. taxes and is called “trapped cash.” Is it time to use some of that cash to snap up what are now bargain‐priced Euro companies? Maybe it's time to “liberate” your trapped cash! © 2013 Wiley Periodicals, Inc.
The Jobs Act: Its Impact on M&A
Authors: Sherman Andrew J. , Brunsdale Shaleen
Published: December 2012

In April 2012, President Barack Obama signed into law the Jumpstart Our Business Startups (JOBS) Act. Its goal was to simplify or reduce the regulatory and legal hurdles faced by emerging companies and ease access to capital and investments. Although many of the implementing regulations are still pending, the passage of the JOBS Act may be able to help small and growing companies access the capital markets more efficiently‐to raise the funds needed to complete merger and acquisition (M&A) transactions. The authors discuss the new law and assess its impact. © 2013 Andrew J. Sherman and Shaleen Brunsdale
Reassessing M&A Valuation Assumptions
Authors: Pandian J. Rajendran , Woodlock Pete
Published: December 2012

The current economic environment has obviously created uncertainty. That uncertainty has caused many companies to focus on preserving capital. So many merger and acquisition (M'A) professionals are scratching their heads and questioning some of the fundamental assumptions that have historically driven business valuations. © 2013 Wiley Periodicals, Inc.
Detecting Fraud: What Are Auditors' Responsibilities?
Authors: Chong Gin
Published: December 2012

High‐profile fraud cases have continued to make the news over the past few years. But exactly what are auditors' responsibilities when it comes to detecting fraud? The author of this article reveals that the auditing profession has come full circle‐from being responsible to not being responsible for detecting fraud. But the volume and critical nature of fraud cases remain high, as do the number of auditing standards addressing this issue. The author explores this problem in depth, identifies situations where fraud may take place, and suggests various tools that auditors should use for fraud detection. © 2013 Wiley Periodicals, Inc.
Does Multistandard Reporting Affect Analysts' Forecasts?
Authors: Yang Ya‐wen , Henry Elaine
Published: December 2012

In 2007, the Securities and Exchange Commission eliminated the reconciliation requirement for non‐U.S. companies that report using International Financial Reporting Standards. Has this affected the accuracy of analysts' forecasts for these companies? The authors conducted a study to find out. © 2013 Wiley Periodicals, Inc.
Driving Acceptance and Adoption of Business Analytics
Authors: Cokins Gary
Published: December 2012

The use of business analytics to gain insight and make better business decisions is rapidly becoming a mainstream business practice. Business analytics allow managers to identify the best results when changes are made to variables in questions such as the following: “Which x is most likely to bring about y?” © 2013 Wiley Periodicals, Inc.
Mortality predictions on admission as a context for organizing care activities
Authors: Cowen Mark E. , Strawderman Robert L. , Czerwinski Jennifer L. , Smith Mary Jo , Halasyamani Lakshmi K.
Published: December 2012

BACKGROUND

Favorable health outcomes are more likely to occur when the clinical team recognizes patients at risk and intervenes in consort. Prediction rules can identify high‐risk subsets, but the availability of multiple rules for various conditions present implementation and assimilation challenges.

METHODS

A prediction rule for 30‐day mortality at the beginning of the hospitalization was derived in a retrospective cohort of adult inpatients from a community hospital in the Midwestern United States from 2008 to 2009, using clinical laboratory values, past medical history, and diagnoses present on admission. It was validated using 2010 data from the same and from a different hospital. The calculated mortality risk was then used to predict unplanned transfers to intensive care units, resuscitation attempts for cardiopulmonary arrests, a condition not present on admission (complications), intensive care unit utilization, palliative care status, in‐hospital death, rehospitalizations within 30 days, and 180‐day mortality.

RESULTS

The predictions of 30‐day mortality for the derivation and validation datasets had areas under the receiver operating characteristic curve of 0.88. The 30‐day mortality risk was in turn a strong predictor for in‐hospital death, palliative care status, 180‐day mortality; a modest predictor for unplanned transfers and cardiopulmonary arrests; and a weaker predictor for the other events of interest.

CONCLUSIONS

The probability of 30‐day mortality provides health systems with an array of prognostic information that may provide a common reference point for organizing the clinical activities of the many health professionals involved in the care of the patient. Journal of Hospital Medicine 2013;8:229–235 © 2012 Society of Hospital Medicine
Low‐density extraction solvent based solvent‐terminated dispersive liquid–liquid microextraction for quantitative determination of ionizable pesticides in environmental waters
Authors: Tolcha Teshome , Merdassa Yared , Megersa Negussie
Published: December 2012

A rapid, efficient, and new solvent terminated dispersive liquid–liquid microextraction technique coupled with HPLC was developed for selective extraction and analysis of s‐triazine herbicides from environmental water samples. Important parameters influencing the extraction process including type and volume of extraction and disperser solvent, extraction time, sample pH, ionic strength, and extraction temperature were successfully optimized. Under the optimal conditions, there are excellent linear relationships between the analytical results and concentration in the range of 10–400 mg/L for atrazine, propazine, prometryn, and terbutryn. LOD and LOQ ranged from 0.60 to 2.33 μg/L and 2.0 to 7.7 μg/L, respectively. Performance of the analytical technique was evaluated by carrying out the repeatability and reproducibility analyses that were ranged from 2.86 to 5.66% and 4.64 to 5.89% for 100 μg/L of each target analyte, respectively. The proposed method has been successfully applied to the analysis of real water samples and acceptable relative recoveries over the range of 65.93–101.46%, with RSDs ≤ 8.80%, were obtained. The overall results have been compared with the literature values. Thus, the method developed could efficiently be used for selective extraction of the target analytes from complex matrices, particularly environmental waters.
Aberrant overexpression of FOXM1 transcription factor plays a critical role in lung carcinogenesis induced by low doses of arsenic
Authors: Liu Youhong , Hock Janet M. , Van Beneden Rebecca J. , Li Xiong
Published: December 2012

Environmental or occupational exposure to low doses of arsenic induces a series of health problems including cancer. The molecular events in arsenic‐induced carcinogenicity remain to be defined. In the NuLi‐1 immortalized human lung epithelial cell line with p53 and pRb deficiency, exposure to low doses of arsenic trioxide for 72 h promoted cell proliferation and upregulated the gene transcription levels of FOXM1, CDC6, CDC25A, and cyclin D1, which are both critical cell cycle regulatory genes and proto‐oncogenes. Continuous in vitro exposure to 1 µM arsenic trioxide for 34 wks induced malignant cell transformation, as evidenced by enhanced anchorage‐independent cell growth. The expression of FOXM1, CDC6, CDC25A, and Cyclin D1 was dynamically elevated at the gene transcription and protein levels in the process of cell transformation. The carcinogenic ability of transformed cell colonies coincides with the expression levels of FOXM1 in in vitro anchorage‐independent growth assays and in vivo tumor xenograft formation assays. In reverse, the knockdown of FOXM1 in lung adenocarcinoma A549 cells or arsenic‐transformed NuLi‐1 cells significantly decreased anchorage‐independent cell growth and tumor xenograft formation. The transformed NuLi‐1 cells showed genomic instability in the form of copy number variation (CNV) at chromosome 1, 5, 6, 18, and 20, but not loss of heterozygosity (LOH). These results showed for the first time that chronic exposure to low doses of arsenic trioxide promoted lung carcinogenicity, in part by aberrantly upregulating FOXM1 and its associated oncogenes, when the tumor suppressor genes p53 and pRb were inactivated. © 2012 Wiley Periodicals, Inc.
Free fasciocutaneous flaps for reconstruction of complete circumferential degloving injury of digits
Authors: Lin Chin‐Ta , Chen Shyi‐Gen , Chen Tim‐Mo , Dai Niann‐Tzyy , Chang Shun‐Cheng
Published: December 2012

Complete circumferential degloving injury of the digits usually results in a large cutaneous defect with tendinous structure and bone and joint exposure. When revascularization is not possible, a thin and adequately sized flap is required to resurface the defect, restore finger function, and prevent amputation. In this report, we present our experience with reconstruction of the entire circumferential degloving injury of the digits using free fasciocutaneous flaps. Between February 2006 and January 2011, 9 male patients with circumferential degloving injury of 9 digits underwent reconstruction using free fasciocutaneous flap transfer with the posterior interosseous artery flap, medial sural artery flap, anteromedial thigh flap, or radial forearm flap. The average flap size was 14.2 × 6.9 cm. Donor sites were closed primarily or covered with split‐thickness skin graft. All flaps survived completely and the donor sites healed without complications. The mean follow‐up period was 34.8 months. A maximum Kapandji score (10/10) was seen in 2 cases with crushed thumbs. All patients could achieve good key pinch and grasping functions. All skin flaps showed acceptable static 2‐point discrimination and adequate protective sensation. Patient satisfaction for resurfaced digits averaged 9 on a 10‐points visual analogic scale. In conclusion, the free fasciocutaneous flaps used were thin and did not interfere with finger movements. The patient's finger formed a smooth contour and acceptable functional results were obtained after reconstruction. This method may be a valuable alternative for reconstruction of entire circumferential avulsion injury of the digits. © 2012 Wiley Periodicals, Inc. Microsurgery, 2013.
Transparent boundary conditions based on the pole condition for time‐dependent, two‐dimensional problems
Authors: Ruprecht Daniel , Schädle Achim , Schmidt Frank
Published: December 2012

The pole condition approach for deriving transparent boundary conditions is extended to the time‐dependent, two‐dimensional case. Nonphysical modes of the solution are identified by the position of poles of the solution's spatial Laplace transform in the complex plane. By requiring the Laplace transform to be analytic on some problem‐dependent complex half‐plane, these modes can be suppressed. The resulting algorithm computes a finite number of coefficients of a series expansion of the Laplace transform, thereby providing an approximation to the exact boundary condition. The resulting error decays super‐algebraically with the number of coefficients, so relatively few additional degrees of freedom are sufficient to reduce the error to the level of the discretization error in the interior of the computational domain. The approach shows good results for the Schrödinger and the drift‐diffusion equation but, in contrast to the one‐dimensional case, exhibits instabilities for the wave and Klein–Gordon equation. Numerical examples are shown that demonstrate the good performance in the former and the instabilities in the latter case. © 2012 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2013
Compact difference schemes for heat equation with Neumann boundary conditions (II)
Authors: Gao Guang‐Hua , Sun Zhi‐Zhong
Published: December 2012

This is the further work on compact finite difference schemes for heat equation with Neumann boundary conditions subsequent to the paper, [Sun, Numer Methods Partial Differential Equations (NMPDE) 25 (2009), 1320–1341]. A different compact difference scheme for the one‐dimensional linear heat equation is developed. Truncation errors of the proposed scheme are O(τ2 + h4) for interior mesh point approximation and O(τ2 + h3) for the boundary condition approximation with the uniform partition. The new obtained scheme is similar to the one given by Liao et al. (NMPDE 22 (2006), 600–616), while the major difference lies in no extension of source terms to outside the computational domain any longer. Compared with ones obtained by Zhao et al. (NMPDE 23 (2007), 949–959) and Dai (NMPDE 27 (2011), 436–446), numerical solutions at all mesh points including two boundary points are computed in our new scheme. The significant advantage of this work is to provide a rigorous analysis of convergence order for the obtained compact difference scheme using discrete energy method. The global accuracy is O(τ2 + h4) in discrete maximum norm, although the spatial approximation order at the Neumann boundary is one lower than that for interior mesh points. The analytical techniques are important and can be successfully used to solve the open problem presented by Sun (NMPDE 25 (2009), 1320–1341), where analyzed theoretical convergence order of the scheme by Liao et al. (NMPDE 22 (2006), 600–616) is only O(τ2 + h3.5) while the numerical accuracy is O(τ2 + h4), and convergence order of theoretical analysis for the scheme by Zhao et al. (NMPDE 23 (2007), 949–959) is O(τ2 + h2.5), while the actual numerical accuracy is O(τ2 + h3). Following the procedure used for the new obtained difference scheme in this work, convergence orders of these two schemes can be proved rigorously to be O(τ2 + h4) and O(τ2 + h3), respectively. Meanwhile, extension to the case involving the nonlinear reaction term is also discussed, and the global convergence order O(τ2 + h4) is proved. A compact ADI difference scheme for solving two‐dimensional case is derived. Finally, several examples are given to demonstrate the numerical accuracy of new obtained compact difference schemes. © 2012 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2013
The management of children with Kaposi sarcoma in resource limited settings
Authors: Molyneux Elizabeth , Davidson Alan , Orem Jackson , Hesseling Peter , Balagadde‐Kambugu Joyce , Githanga Jessie , Israels Trijn
Published: December 2012

Kaposi sarcoma (KS) is common where HIV infection is endemic. Antiretroviral therapy (ART) has reduced the incidence in well‐resourced settings but in some parts of the world access to ART is delayed. These recommendations are for use where only minimal requirements for treatment are available. Consensus was sought for the management of childhood HIV‐associated KS in this setting. There are no randomised controlled studies of chemotherapy for KS in children and these recommendations have drawn on consensus of a group of experts and published reports from studies in adults. Pediatr Blood Cancer 2013; 60: 538–542. © 2012 Wiley Periodicals, Inc.