bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterization of the G‐quadruplex structure of a catalytic DNA with peroxidase activity
Authors: Kong De‐Ming , Cai Li‐Li , Guo Jun‐Hong , Wu Jing , Shen Han‐Xi
Published: January 2009

It has been reported that the complexes formed by hemin and some G‐quadruplexes can be developed as a new class of DNAzyme with peroxidase activity. This kind of DNAzyme has received a great deal of attention. But to date, the actual G‐quadruplex structure that can provide hemin with enhanced peroxidase activity is in doubt. Herein, the G‐quadruplex structure of CatG4, a 21‐nucleotide DNA oligomer which was previously reported to bind hemin and the resulting complex exhibiting enhanced peroxidase activity, was characterized by fluorescence and circular dichroism measurements. The results suggest that the catalytically active form of CatG4 may be a unimolecular parallel quadruplex rather than a unimolecular chair‐type antiparallel quadruplex or a multistranded parallel quadruplex. In addition, the fluorescence analysis of labeled oligonucleotides may be developed as a supplementary tool for the study of DNA conformations. © 2009 Wiley Periodicals, Inc. Biopolymers 91: 331–339, 2009.

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
FtsZ condensates: An in vitro electron microscopy study
Authors: Popp David , Iwasa Mitsusada , Narita Akihiro , Erickson Harold P. , Maéda Yuichiro
Published: January 2009

In vivo cell division protein FtsZ from E. coli forms rings and spirals which have only been observed by low resolution light microscopy. We show that these suprastructures are likely formed by molecular crowding which is a predominant factor in prokaryotic cells and enhances the weak lateral bonds between proto‐filaments. Although FtsZ assembles into single proto‐filaments in dilute aqueous buffer, with crowding agents above a critical concentration, it forms polymorphic supramolecular structures including rings and toroids (with multiple protofilaments) about 200 nm in diameter, similar in appearance to DNA toroids, and helices with pitches of several hundred nm as well as long, linear bundles. Helices resemble those observed in vivo, whereas the rings and toroids may represent a novel energy minimized state of FtsZ, at a later stage of Z‐ring constriction. We shed light on the molecular arrangement of FtsZ filaments within these suprastructures using high resolution electron microscopy. © 2009 Wiley Periodicals, Inc. Biopolymers 91: 340–350, 2009.

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Revival of the biological sunlight‐to‐biogas energy conversion system
Authors: De Schamphelaire Liesje , Verstraete Willy
Published: January 2009

In the quest for renewable resources, algae are increasingly receiving attention. Their high growth rate, high CO2 fixation and their lack of requirement for fertile soil surface represent several advantages as compared to conventional (energy) crops. Through their ability to store large amounts of oils, they qualify as a source for biodiesel. Algal biomass, however, can also be used as such, namely as a substrate for anaerobic digestion. In the present research, we investigated the use of algae for energy generation in a stand‐alone, closed‐loop system. The system encompasses an algal growth unit for biomass production, an anaerobic digestion unit to convert the biomass to biogas and a microbial fuel cell to polish the effluent of the digester. Nutrients set free during digestion can accordingly be returned to the algal growth unit for a sustained algal growth. Hence, a system is presented that continuously transforms solar energy into energy‐rich biogas and electricity. Algal productivities of 24–30 ton VS ha−1 year−1 were reached, while 0.5 N m3 biogas could be produced kg−1 algal VS. The system described resulted in a power plant with a potential capacity of about 9 kW ha−1 of solar algal panel, with prospects of 23 kW ha−1. Biotechnol. Bioeng. 2009;103: 296–304. © 2009 Wiley Periodicals, Inc.
Carbon‐based sorbents in chromatography. New achievements
Authors: Cserháti T.
Published: January 2009

The newest results in the employment of carbon‐based composites in various chromatographic techniques such as gas–liquid chromatography, high‐performance liquid chromatography and electrically driven separation techniques for the separation, quantitative determination and identification of a wide variety of compounds in complicated matrices are compiled. The results are concisely described and critically evaluated. The future trends in the application of carbon‐based compounds in the chromatographic separation methods are briefly discussed. Copyright © 2008 John Wiley & Sons, Ltd.
Friendly interface to learn stereovision theory
Authors: Castejón C. , Blanco D. , Moreno L.
Published: January 2009

The main objective in this manuscript is the development of a graphical user interface to learn stereovision techniques. The interface will let the student obtain 3D results with stereo cameras in an easy way and without previous theory knowledge. The didactic and ease to obtain results in the first learning stage is demonstrated to be a good training for students motivation in order to learn the theoretical bases. The package developed (stereo interface) is formed by a vision system or a library of stereo pair images, and an application based on Windows™ and MATLAB® with its image processing and GUIDE toolboxes. MATLAB® allows interactive visual communication among students and perception system to understand, by means of the experimentation, the most important features related to the stereo theory. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 17: 180–186, 2009; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae20170
An XUP–UNM educational platform: A dual‐FPGA platform for reconfigurable logic
Authors: Kief C. J. , Pattichis Marios S. , Pollard L. Howard , Vera G. Alonzo , Parra Jorge E.
Published: January 2009

We present a new educational platform for teaching reconfigurable logic. The new platform includes two FPGAs, separate instruction and data buses, serial and parallel port connections, and extensive I/O connections for interfacing with other reconfigurable computing boards. The platform was successfully tested at the University of New Mexico, the University of Texas at Austin, the University of Texas at El Paso, and the West Point military academy. Online documentation details the entire design, fabricating, assembly, and testing phases. All design information is freely available online. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 17: 232–239, 2009; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae20192
An educational computer tool for simulating long‐term soil erosion on agricultural landscapes
Authors: Jiménez‐Hornero F. J. , Giráldez J. V. , Laguna A. M. , Jiménez‐Hornero J. E.
Published: January 2009

Due to its economic and environmental impacts, soil erosion has been a major concern to farmers, engineers and policy makers in recent years. Water and tilling are two of the main agents responsible for this phenomenon and considerable efforts have been made to model them in previous work but not with educational purposes. A computer tool for facilitating any user's simulation of long‐term landscape evolution in a plot due to the combined action of water and tillage erosion is presented here. It integrates a graphic user interface with two well‐verified erosion models, each one independently devoted to reproduce the effects of water and tilling. This computer tool permits to the student the consideration of the erosivity index and the presence of a crop in the plot, when simulating water erosion, as well as the planning of a different type of tilling each year. Each kind of tilling corresponds to a different combination of tillage tools with their own date, tillage depth and tillage direction. A handy ASCII (XYZ) file is generated containing the long‐term soil erosion spatial pattern as result. From this information, the student can derive other results that will help to understand soil erosion. An example is presented here with the aim of showing how to use this computer tool to simulate this phenomenon on an agricultural landscape with a complex topography. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 17: 253–262, 2009; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20193
Development of a computer‐aided educational tool incorporating MATLAB for engineering measurements
Authors: Tan F. L. , Fok S. C.
Published: January 2009

This paper presents the development of a multimedia package to help students in the learning of engineering measurements. The stimulus for developing the computer‐aided educational tool derives from the continuing need for engineers to understand and apply mathematical models in the design of measurement systems. Besides providing fundamental background in the theory of engineering measurements, the main features of the computer‐aided tool include the integration of multimedia with Matlab and Microsoft Excel to allow students to conceptualize the relationship between abstract mathematical models to practical situations. The integration not only provides interactively facilities to engage students in the exploration of signals and measurement system behaviors, but also offers random dynamic quizzes that could automatically change the question parameter and generate the correct answer. The considerations and discussions in this paper may be useful for the advancement of computer‐aided instructional tools in other subject areas. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 17: 206–213, 2009; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae20204
Haptic ventriculostomy simulation in a grid environment
Authors: Çakmak H. , Maaß H. , Trantakis C. , Strauß G. , Nowatius E. , Kühnapfel U.
Published: January 2009

We present a full featured surgery simulator for endoscopic third ventriculostomy (ETV) in an interactive grid environment. The basic ventriculostomy simulator introduced previously has been extended with new 3D models and animation methods for raising the simulation realism. It enables full haptic interaction with textured deformable models of a hydrocephalic configured human ventricular system derived from MR‐data. Visual effects like bleeding in the cerebrospinal fluid (CSF) have been implemented for faulty interactions during training sessions which are recorded in a database for further evaluation. Based on the training data comparative studies were carried out whereas the benefits of virtual reality (VR)‐based training have been demonstrated. Furthermore, KisGrid is presented as an interactive grid environment for real‐time surgical simulators. It enables collaborative and supervised haptic training over networks with access to remote surgical models and hardware. The grid applet ViCoM is introduced as a tool for audio‐visual communication, monitoring, and training session archiving. Long distance tests have been successfully carried out for multicast video conferencing, training session monitoring, and haptic surgical collaboration with deformable models. Copyright © 2009 John Wiley & Sons, Ltd.
The Protein Environment Drives Selectivity for Sulfide Oxidation by an Artificial Metalloenzyme
Authors: Rousselot‐Pailley Pierre , Bochot Constance , Marchi‐Delapierre Caroline , Jorge‐Robin Adeline , Martin Lydie , Fontecilla‐Camps Juan C. , Cavazza Christine , Ménage Stéphane
Published: January 2009

Magic Mn–salen metallozyme: The design of an original, artificial, inorganic, complex‐protein adduct, has led to a better understanding of the synergistic effects of both partners. The exclusive formation of sulfoxides by the hybrid biocatalyst, as opposed to sulfone in the case of the free inorganic complex, highlights the modulating role of the inorganic‐complex‐binding site in the protein.

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Artificial metalloenzymes based on the incorporation of Mn–salen complexes into human serum albumin display high efficiency and selectivity for sulfoxide production during sulfide oxidation. The reactions carried out by the artificial metallozymes are comparable to those carried out by natural biocatalysis. We have found that the polarity of the protein environment is crucial for selectivity and that a synergy between both partners of the hybrid results in the novel activity.
Altering the Substrate Specificity of RhlI by Directed Evolution
Authors: Kambam Pavan Kumar Reddy , Eriksen Dawn T. , Lajoie Jason , Sayut Daniel J. , Sun Lianhong
Published: January 2009

Reducing virulence: RhlI catalyzes the synthesis of N‐butanoyl homoserine lactone (BHL), with a minor product N‐hexanoyl homoserine lactone (HHL). By using directed evolution and a genetic screen, RhlI has been engineered for enhanced production of both BHL and HHL at a similar level.

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Quorum sensing regulates biofilm formation and virulence factor production in the human opportunistic pathogen Pseudomonas aeruginosa. We used directed evolution to engineer RhlI, an enzyme in the RhlI–RhlR quorum‐sensing system of P. aeruginosa, to alter its substrate specificity and gain insight into the molecular mechanisms of quorum sensing. By using a genetic screen, we identified a mutant with improved production of RhlI's two signaling molecules, N‐butanoyl‐ and N‐hexanoyl‐homoserine lactone (BHL and HHL). In particular, production of BHL has been enhanced by more than two‐fold, and the synthesis of HHL has been improved from an undetectable level to a level similar to BHL; this change indicates a significant change in substrate specificity. No significant change in the gene expression level was observed. Sequence alignments suggest that the mutations are most likely to facilitate interactions between the enzyme and the two acylated ACP substrates. This work also demonstrates that the genetic screen/selection should be useful in engineering additional quorum‐sensing components.
Percutaneous closure of aortic pseudoaneurysm by Amplatzer occluder device—Case series of six patients
Authors: Hussain Jamal , Strumpf Robert , Wheatley Grayson , Diethrich Edward
Published: January 2009

Thoracic pseudoaneurysms are rare variety of aortic disorders. Although mostly asymptomatic, they represent potentially fatal conditions (Sullivan et al., Chest 1988;93:138–143; Razzouk et al., Ann Surg 1993;59:818–823) that are traditionally treated surgically. False aneurysms of aorta are usually a late complication of previous surgical procedure (Sullivan et al., 1988)‐especially reconstructive surgery, trauma (Razzouk et al., 1993), and rarely infection (Sanchez‐Recalde et al., J Am Coll Cardiol 2003;41:152–154). Surgical management is often complicated by poor outcomes with high morbidity and mortality (Mulder et al., Arch Surg 1998;133:45–49). Endovascular treatment is emerging as promising options for aortic diseases with fewer complications. We report a series of six cases at a single center where Amplatzer devise was used to treat thoracic aortic pseudo aneurysm. To our knowledge only one series of three cases (Kanani et al., Catheter Cardiovasc Interv 2007;69:146–153) and few case reports (Bashi et al., Catheter Cardiovasc Interv 2005;65:547–551) of successful closure have been published previously. Our case series is the largest, so far, including mortality and specifically the preprocedural and postprocedural CT angiographic assessment of the pseudoaneurysms. © 2008 Wiley‐Liss, Inc.
Prevention and treatment of venous thromboembolism during pregnancy
Authors: Weitz Jeffrey I.
Published: January 2009

Women who are pregnant or have recently given birth are at significantly increased risk of venous thromboembolism (VTE) compared with the general population. Furthermore, the issues surrounding the appropriate prevention, diagnosis, and treatment of VTE are more complex in pregnancy, where not only the effects on the mother, but also the effects on the fetus need to be considered. Although guidelines provide recommendations for the optimal management of these patients, most of these guidelines are based on evidence from observational studies, or on data extrapolated from a nonpregnant population. Randomized clinical trials are needed to identify the optimal strategies for prevention and treatment of VTE in pregnancy. © 2009 Wiley‐Liss, Inc.
New bioabsorbable septal repair implant for percutaneous closure of a patent foramen ovale: Short‐term results of a single‐centre experience
Authors: Van den Branden B.J.L. , Post M.C. , Jaarsma W. , ten Berg J.M. , Suttorp M.J.
Published: January 2009

Background:

Permanent implants for closure of a patent foramen ovale (PFO) have a number of possible disadvantages including erosions, thrombus formation, and allergic reactions. The incidence of adverse events may be lower using a bioabsorbable device.

Objective:

To evaluate the short‐term safety and efficacy of a new bioabsorbable closure device.

Methods:

All 35 consecutive patients (21 female, mean age 47.9 ± 10.8 years), who underwent a percutaneous PFO closure between November 2007 and July 2008, were included. All complications were reported. The efficacy was based on the residual shunting the day after implant and at 1 month follow‐up and was graded as minimal, moderate, or severe, using contrast transthoracic echocardiography with the Valsalva manoeuvre.

Results:

The only in‐hospital complication was a surgical device retrieval from the femoral vein. Four patients developed a minimal inguinal haematoma. One day after closure, residual shunting was present in 56% of the patients (minimal 27%, moderate 23% and severe 6%). At 1 month follow‐up (n = 33), one patient developed a transient neurological deficit and three patients suffered from paroxysmal atrial fibrillation. A residual shunt at 1 month was present in 45% of the patients (minimal 30%, moderate 12%, and severe 3%).

Conclusions:

Percutaneous PFO closure using the bioabsorbable closure device seems to be safe. However, a high rate of residual shunting is present at 1 month follow‐up. Long‐term follow‐up data are necessary to evaluate the efficacy and safety of this device. © 2009 Wiley‐Liss, Inc.
Regression byL1regularization of smart contrasts and sums (ROSCAS) beats PLS and elastic net in latent variable model
Authors: ter Braak Cajo J. F.
Published: January 2009

This paper proposes a regression method, ROSCAS, which regularizes smart contrasts and sums of regression coefficients by anL1penalty. The contrasts and sums are based on the sample correlation matrix of the predictors and are suggested by a latent variable regression model. The contrasts express the idea thata prioricorrelated predictors should have similar coefficients. The method has excellent predictive performance in situations, where there are groups of predictors with each group representing an independent feature that influences the response. In particular, when the groups differ in size, ROSCAS can outperform LASSO, elastic net, partial least squares (PLS) and ridge regression by a factor of two or three in terms of mean squared error. In other simulation setups and on real data, ROSCAS performs competitively. Copyright © 2009 John Wiley & Sons, Ltd.
Studies on the Efficient Generation of PhosphorusCarbon Bonds via a Rearrangement of PIII Esters Catalysed by Trimethylhalosilanes
Authors: Dabkowski Wojciech , Ozarek Alfred , Olejniczak Sebastian , Cypryk Marek , Chojnowski Julian , Michalski Jan
Published: January 2009

Unprecedented CP systems: Me3SiX (X=Br, I) catalyses rearrangements of PIII esters R′R′′POR into the corresponding phosphoryl systems, providing a simple, mild and efficient route to a variety of structures containing PC bonds. The mechanism has been found to be fundamentally different from that of the Arbuzov–Michaelis reaction and includes three definite steps a, b and c (see scheme).

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Halotrimethylsilanes Me3SiX (X=Br, I) catalyse rearrangements of tricoordinate phosphorus esters R′R′′POR into the corresponding phosphoryl systems R′R′′P(O)R. This provides a simple and efficient route to a variety of structures containing phosphoruscarbon bonds, under mild conditions and with good yields. The reaction mechanism was investigated in detail by 31P NMR spectroscopy and independent synthesis of the reaction intermediates. It has been demonstrated that the primary products of this catalytic reaction are halogeno PIII structures R′R′′PX and silyl ethers ROSiMe3 and that they subsequently react to give the corresponding phosphorus silyl esters—Me3SiOPR′R′′—and alkyl halides RX. At higher temperatures these intermediates then react to form R′R′′P(O)R compounds. This paper also features the surprising observation that when esters Ph2POR and halotrimethylsilanes Me3SiX (X=Br, I) are used in 2:1 ratio, phosphonium salts Ph2R2P+X− and trimethylsilyl diphenylphosphinate—Ph2P(O)OSiMe3 —are formed as the major products. Experimental evidence indicates that the mechanisms of both reactions are fundamentally different from that of the Michaelis–Arbuzov reaction. Me3SiCl is not reactive and this paper explains why.
Tuning Single‐Molecule Dynamics in Functionalized Mesoporous Silica
Authors: Lebold Timo , Mühlstein Lea A. , Blechinger Julia , Riederer Melanie , Amenitsch Heinz , Köhn Ralf , Peneva Kalina , Müllen Klaus , Michaelis Jens , Bräuchle Christoph , Bein Thomas
Published: January 2009

Diffusion of single molecules of a substituted terrylene diimide dye in functionalized mesoporous silica films was monitored by single‐molecule fluorescence microscopy. By varying the chemical nature and density of the functional groups, the diffusion dynamics of the dye molecules can be controlled precisely. The picture shows a sketch of a dye molecule in a pore, diffusion data for different phenyl functionalization densities, and the trajectory of one molecule in a cyanopropyl‐functionalized film.

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Mesoporous silica materials are promising host structures for diverse applications in nanoscience. Many applications can profit significantly from the ability to influence guest dynamics in the host matrix. To this end, we introduce covalently attached organic functionalization into the walls of mesoporous silica networks. Using single‐molecule fluorescence microscopy, we study the diffusion behavior of single terrylene diimide dye molecules in functionalized mesoporous silica films. We show that, through variation of the chemical nature and density of the functional groups, the diffusion dynamics of the dye molecules, in the presence of the surfactant template, can be controlled precisely. The mean diffusion coefficient of the dye molecules increases or decreases depending on the functional group attached to the silica wall. This allows fine‐tuning of the diffusion dynamics of the dye by approximately one order of magnitude. The observed changes in the mean diffusion coefficients can be explained by shielding of hydroxyl groups on the silica surface in combination with changes in the rigidity of the micellar packing in the film, as well as direct interactions between the functional groups and the dye molecules.
Speciation of Rare‐Earth Metal Complexes in Ionic Liquids: A Multiple‐Technique Approach
Authors: Nockemann Peter , Thijs Ben , Lunstroot Kyra , Parac‐Vogt Tatjana N. , Görller‐Walrand Christiane , Binnemans Koen , Van Hecke Kristof , Van Meervelt Luc , Nikitenko Sergey , Daniels John , Hennig Christoph , Van Deun Rik
Published: January 2009

The dissolution process of metal complexes in ionic liquids was investigated by a multiple‐technique approach to reveal the solvate species of the metal in solution. The task‐specific ionic liquid betainium bis(trifluoromethylsulfonyl)imide ([Hbet][Tf2N]) is able to dissolve stoichiometric amounts of the oxides of the rare‐earth elements. The crystal structures of the compounds [Eu2(bet)8(H2O)4][Tf2N]6, [Eu2(bet)8(H2O)2][Tf2N]6⋅2H2O, and [Y2(bet)6(H2O)4][Tf2N]6 were found to consist of dimers. These rare‐earth complexes are well soluble in the ionic liquids [Hbet][Tf2N] and [C4mim][Tf2N] (C4mim=1‐butyl‐3‐methylimidazolium). The speciation of the metal complexes after dissolution in these ionic liquids was investigated by luminescence spectroscopy, 1H, 13C, and 89Y NMR spectroscopy, and by the synchrotron techniques EXAFS (extended X‐ray absorption fine structure) and HEXS (high‐energy X‐ray scattering). The combination of these complementary analytical techniques reveals that the cationic dimers decompose into monomers after dissolution of the complexes in the ionic liquids. Deeper insight into the solution processes of metal compounds is desirable for applications of ionic liquids in the field of electrochemistry, catalysis, and materials chemistry.
[M(N3)2(H2O)2]⋅(bpeado): Unusual Antiferromagnetic Heisenberg Chain (M=Mn) and Ferromagnetic Ising Chain (M=Co) with Large Coercivity and Magnetic Relaxation (bpeado=1,2‐Bis(4‐pyridyl)ethane‐N,N′‐dioxide)
Authors: Sun Hao‐Ling , Wang Zhe‐Ming , Gao Song
Published: January 2009

Contrasting magnetic properties: Two isostructural metal‐azido magnetic chains embedded in 3D threefold interpenetrated H‐bonded frameworks and separated by a long bpeado spacer have been assembled (see figure). Incorporation of Mn2+ displays a rarely observed antiferromagnetic Heisenberg chain, while incorporation of Co2+ displays a ferromagnetic Ising chain.

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We present here the structures and magnetism of two isostructural magnetic metal‐azido chain compounds of the type [M(N3)2(H2O)2]⋅(bpeado) (1, M=Mn; 2, M=Co; bpeado=1,2‐bis(4‐pyridyl)ethane‐N,N′‐dioxide), prepared by utilizing the long spacer bpeado. The structure is composed of [M(N3)2(H2O)2]n metal‐azido chains, in which metal ions are bridged by two end‐on azido ligands, and the chains are further supported by H‐bonding interactions between the coordination water of the chain and the lattice bpeado in a three‐dimensional (3D) threefold interpenetrated H‐bonded framework. Within the structure, the metal‐azido chains are separated quite well. Investigation of the magnetic properties has revealed that the Mn compound 1 is an isotropic Heisenberg chain with unusual antiferromagnetic coupling between the Mn2+ ions linked by double end‐on azide anions. The Co compound 2 shows a strong anisotropic Ising‐type ferromagnetic chain within the material. Detailed magnetic studies on both polycrystalline and single‐crystal samples of 2 have revealed a large coercivity of up to 37.5 kOe (along the crystallographic b‐axis), multi‐magnetic transitions, and single‐chain‐magnet‐like magnetic relaxation behavior.
A Synthetic Method for Transition‐Metal Chalcogenide Nanocrystals
Authors: Wang Ding‐Sheng , Zheng Wen , Hao Chen‐Hui , Peng Qing , Li Ya‐Dong
Published: January 2009

A facile wet route was applied to prepare a series of chalcogenide semiconductor nanocrystals (see figure) in controllable shapes and sizes, while a general bottom‐up approach was adopted to transform these cyclohexane‐soluble monodisperse nanocrystals into water‐soluble colloidal spheres.

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In this paper, we prepared a series of chalcogenide semiconductor nanocrystals in controllable shape and size via a facile wet route using metal nitrates and sulfur or selenium powder as precursors and octadecylamine (ODA) as solvent. The as‐obtained chalcogenides included CdS, MnS, Ag2S, PbS, Cu1.8S, Bi2S3, ZnS, ZnxCd1−xS, as well as Ag2Se, Cu2−xSe, CdSe, MnSe. Furthermore, these cyclohexane‐soluble monodisperse nanocrystals were assembled to water‐soluble colloidal spheres and the adjustment of assembly orderliness has been achieved by controlling the experimental parameters. The general synthesis and assembly of chalcogenide semiconductors provide ideal building blocks for various potential applications.
Base‐Pairing Directed Folding of a Bimolecular G‐Quadruplex: New Insights into G‐Quadruplex‐Based DNAzymes
Authors: Li Tao , Wang Erkang , Dong Shaojun
Published: January 2009

Base pairs, magic hands: An additional base‐pairing duplex is utilized to control the folding topologies of a bimolecular G‐quadruplex formed by two G‐rich single‐stranded DNAs (see picture), which is dependent on the position of base pairs. This study clearly reveals an important intrinsic role of additional base pairs in the G‐quadruplex structure, and also provides a clue to the formation mechanism of the G‐quadruplex‐based DNAzyme.

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Solid‐Phase Synthesis of Peptide Libraries Combining α‐Amino Acids with Inorganic and Organic Chromophores
Authors: Heinze Katja , Hempel Klaus
Published: January 2009

The synthesis of two series of peptidic chains composed of bis(terpyridine)ruthenium(II) acceptor units and organic chromophores (coumarin, naphthalene, anthracene, fluorene) by stepwise solid‐phase peptide synthesis (SPPS) techniques is described. The first series of dyads comprises directly amide linked chromophores, while the second one possesses a glycine spacer between the two chromophores. All dyads were studied by UV/Vis and NMR spectroscopy, steady‐state luminescence, luminescence decay and electrochemistry, as well as by DFT calculations. The results of these studies indicate weak electronic coupling of the chromophores in the ground state. Absorpion spectra of all dyads are dominated by metal‐to‐ligand charge‐transfer (MLCT) bands around 500 nm. The bichromophoric systems, especially with coumarin as organic chromophore, display additional strong absorptions in the visible spectral region. All complexes are luminescent at room temperature (3MLCT). Efficient quenching of the fluorescence of the organic chromophore by the attached ruthenium complex is observed in all dyads. Excitation spectra indicate energy transfer from the organic dye to the ruthenium chromophore.
Highly Selective Dehydrogenative Silylation of Alkenes Catalyzed by Rhenium Complexes
Authors: Jiang Yanfeng , Blacque Olivier , Fox Thomas , Frech Christian M. , Berke Heinz
Published: January 2009

Choosy chemicals: Rhenium(I) complexes of type [ReBr2(L)(NO)(PR3)2] (L=H2 (1), CH3CN (2), ethylene (3); R=iPr (a), cyclohexyl (b)) proved to be suitable catalyst precursors for the highly selective dehydrogenative silylation of alkenes. Two types of rhenium(I) hydride species, [ReBrH(NO)(PR3)2] (4) and [ReBr(η2‐CH2CHR1)H(NO)(PR3)2] (5), were found in the [ReBr2(L)(NO)(PR3)2]‐catalyzed dehydrogenative silylation of alkenes.

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Rhenium(I) complexes of type [ReBr2(L)(NO)(PR3)2] (L=H2 (1), CH3CN (2), and ethylene (3); R=iPr (a) and cyclohexyl (Cy; b)) catalyze dehydrogenative silylation of alkenes in a highly selective manner to yield silyl alkenes and the corresponding alkanes. Hydrosilylation products appear only rarely depending on the type of olefinic substituent, and if they do appear then it is in very minor amounts. Mechanistic studies showed that two rhenium(I) hydride species of type [ReBrH(NO)(PR3)2] (R=iPr (4 a) and Cy (4 b)) and [ReBr(η2‐CH2CHR1)H(NO)(PR3)2] (R1=p‐CH3C6H4, R=iPr (5 a), Cy (5 b); R1=H, R=iPr (5 a′), Cy (5 b′)) are involved in the initiation pathway of the catalysis. The rate‐determining steps of the catalytic cycle are the phosphine dissociation from complexes of type 5 and the reductive eliminations to form the alkane components. The catalytic cycle implies that the given rhenium systems have the ability to activate CH and SiH bonds through the aid of a facile redox interplay of ReI and ReIII species. The molecular structures of 4 b and 5 a were established by means of X‐ray diffraction studies.
Selective Chromofluorogenic Sensing of Heparin by using Functionalised Silica Nanoparticles Containing Binding Sites and a Signalling Reporter
Authors: Climent Estela , Calero Pilar , Marcos M. Dolores , Martínez‐Máñez Ramón , Sancenón Félix , Soto Juan
Published: January 2009

Heparin detective: Silica nanoparticles functionalised with ion‐channel scaffolds were prepared and used for the chromofluorogenic sensing of heparin in aqueous environments (see figure). The surface of the nanoparticles was functionalised with polyamines (binding sites) and thiols. The reaction of a dye (squaraine) with the surface thiol groups was selectively inhibited by the coordination of heparin with the partly protonated polyamines.

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Efficient Air‐Stable Organometallic Low‐Molecular‐Mass Gelators for Ionic Liquids: Synthesis, Aggregation and Application of Pyridine‐Bridged Bis(benzimidazolylidene)–Palladium Complexes
Authors: Tu Tao , Bao Xiaoling , Assenmacher Wilfried , Peterlik Herwig , Daniels Jörg , Dötz Karl Heinz
Published: January 2009

Beyond catalysis: Novel pincer‐type pyridine‐bridged bis(benzimidazolylidene)–palladium complexes have been synthesised and shown to efficiently gelate a variety of solvents and customary ionic liquids. π‐Stacking, van der Waals interactions, hydrogen and metal–metal bonding are responsible for 3D gel networks formed by the metallogelators.

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Novel pincer‐type, pyridine‐bridged bis(benzimidazolylidene)–palladium complexes 5–7 were synthesised from cheap commercial precursors under microwave assistance. Although simple in structure, carbene complexes 5 a,b are efficient low‐molecular‐mass metallogelators. They gelate not only a broad variety of protic and aprotic organic solvents, but also different types of customary ionic liquids (such as imidazolium, pyridinium, pyrazolidinium, piperidinium and ammonium salts) at concentrations as low as 0.5 mg mL−1. The morphologies of the resulting 3D gel networks composed from long and thin fibres were studied by TEM and light microscopy for a selection of organic and ionic liquids. The achiral gelators are able to induce the formation of helical fibres. The thermal stability of the gel samples increases with the gelator concentration as demonstrated by thermoreversible DSC studies. Temperature‐dependent NMR and X‐ray diffraction studies, as well as comparisons with pincer complex analogues bearing shorter alkyl chains, suggest that the 3D networks responsible for gelation are based on non‐covalent interactions, such as π‐stacking, van der Waals interactions, and hydrogen and metal–metal bonding. Ionic liquids and gels obtained from them and 5 a,b display comparable high conductivities, which characterises pyridine‐bridged bis(benzimidazolylidene)–palladium pincer complexes as air‐stable metallo gelators that efficiently immobilise ionic liquids in low gelator concentration indicating—beyond catalysis—their potential applications in electrochemical devices.
N4‐Tetradentate Dicarboxyamidate/Dipyridyl Palladium Complexes as Robust Catalysts for the Heck Reaction of Deactivated Aryl Chlorides
Authors: Srinivas Pottabathula , Likhar Pravin R. , Maheswaran Hariharasarma , Sridhar Balasubramanian , Ravikumar Krishnan , Kantam Mannepalli Lakshmi
Published: January 2009

Structurally well defined and thermally stable PdII complexes, derived from N4‐tetradentate dicarboxyamide/dipyridyl ligands, were evaluated as catalysts for the Heck reactions of deactivated aryl chlorides and olefins (see scheme). The concept of using an anionic carboxyamide as an ancillary ligand for palladium demonstrated here provides a new opportunity for the development of phosphine‐free transition‐metal catalysis.

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No Abstract
Enantioselective and Catalytic Method for α‐Crotylation of Aldehydes with a Kinetic Self‐Refinement of Stereochemistry
Authors: Malkov Andrei V. , Kabeshov Mikhail A. , Barłog Maciej , Kočovský Pavel
Published: January 2009

Kinetic refinery: A practical, highly stereoselective, two‐step catalytic protocol for the α‐allylation of aldehydes, starting from crotyltrichlorosilanes, has been developed (see scheme). In each reaction step, one of the stereoisomers reacted faster than the other, which resulted in a kinetic stereochemical (E/Z) self‐refinement of the system and led to the formation of virtually enantiomerically and geometrically pure linear homoallylic alcohols in high yield.

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No Abstract
On the Possibility of Conversion of Alcohols to Ketones and Aldehydes by Phosphinoboranes R2PBR′R′′: A Computational Study
Authors: Privalov Timofei
Published: January 2009

Can phosphinoboranes promote hydrogenation of carbonyl moieties? By means of B3LYP and MPW1K density functional calculations the likelihood of the oxidation of alcohols by phosphinoboranes R2PBR′2 (1) was explored. As a proof‐of‐principle, a theoretical study that tests the reversibility of the alcohol oxidation is reported. The potential of 1 as a metal‐free hydrogenation mediator is discussed for a series of hydrogen sources such as primary and secondary alcohols.

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ChemInform Abstract: Reactions of Uranium Atoms with Ammonia: Infrared Spectra and Quasi‐Relativistic Calculations of the U:NH3, H2N—UH, and HN=UH2 Complexes.
Authors: Wang Xuefeng , Andrews Lester , Marsden Colin J.
Published: January 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: A 119Sn Moessbauer and 45Sc Solid State NMR Spectroscopic Study of the Stannides ScTSn (T: Ni, Pd, Pt).
Authors: Harmening Thomas , Sebastian C. Peter , Zhang Long , Fehse Constanze , Eckert Hellmut , Poettgen Rainer
Published: January 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Crystal Structure of a Zn‐Doped Derivative of the Li17Ge4 Compound.
Authors: Lacroix‐Orio L. , Tillard M. , Belin C.
Published: January 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Crystal Structure of the 2/1 Cubic Approximant Ag42In42Yb16.
Authors: Li M. R. , Hovmoeller S. , Sun J. L. , Zou X. D. , Kuo K. H.
Published: January 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Tt—Tt (Tt: Si, Ge) Dumb‐Bell Structures at Different Valence Electron Concentrations: Ln2MgSi2 (Ln: La, Ce), Yb2Li0.5Ge2, and Yb1.75Mg0.75Si2.
Authors: Xie Qinxing , Kubata Christof , Woerle Michael , Nesper Reinhard
Published: January 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: The Crystal Structure and Thermal Expansion Properties of Solid Solutions Ln2‐xDyxW3O12 (Ln: Er and Y).
Authors: Xiao X. L. , Peng J. , Wu M. M. , Cheng Y. Z. , Chen D. F. , Hu Z. B.
Published: January 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Preparation, Crystal Structure, and Photoluminescence of Ca2SnO4:Eu3+, Y3+.
Authors: Yamane Hisanori , Kaminaga Yusuke , Abe Shunsuke , Yamada Takahiro
Published: January 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Preparation of New Lithium Ion Composite Electrolyte 3Li4SiS4—0.5La2S3 by Mechanical Milling.
Authors: Liu Zhanqiang , Huang Fuqiang , Yang Jianhua , Wang Yaoming , Sun Junkang
Published: January 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Investigaton of the Thermodynamics Governing Metal Hydride Synthesis in the Molten State Process.
Authors: Stowe Ashley C. , Berseth Polly A. , Farrell Thomas P. , Laughlin Laura , Anton Donald , Zidan Ragaiy
Published: January 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Solid Solutions of Perovskite in the LaO1.5—BaO—ScO1.5—ZrO2 System at 1600 °C
Authors: Suehiro Koichi , Imashuku Susumu , Uda Tetsuya , Nose Yoshitaro , Awakura Yasuhiro
Published: January 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Spinel Li4Ti5O12 as a Reversible Anode Material Down to 0 V.
Authors: Yao X. L. , Xie S. , Nian H. Q. , Chen C. H.
Published: January 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: NMR Spectroscopic Studies of Interactions in Solution During the Synthesis of MoVTeNb Oxide Catalysts.
Authors: Maksimovskaya Raisa I. , Bondareva Valentina M. , Aleshina Galina I.
Published: January 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Mesoporous Bismuth Titanate with Visible‐Light Photocatalytic Activity.
Authors: Kong Lingdong , Chen Haihan , Hua Weiming , Zhang Shicheng , Chen Jianmin
Published: January 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Improved Hydrogen Sorption of Sodium Alanate by Optimized Processing.
Authors: Eigen N. , Gosch F. , Dornheim M. , Klassen T. , Bormann R.
Published: January 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Novel Oxonium Halogenochalcogenates Stabilized by Crown Ethers: [H3O(Dibromo‐benzo‐18‐crown‐6)]2 [Se3Br10] and [H5O2(Bis‐dibromo‐dibenzo‐24‐crown‐8)]2 [Se3Br8].
Authors: Beckmann Illenora , Laege Mechtild , Krebs Bernt
Published: January 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: New Layered Rare‐Earth Hydroxides with Anion‐Exchange Properties.
Authors: Geng Fengxia , Xin Hao , Matsushita Yoshitaka , Ma Renzhi , Tanaka Masahiko , Izumi Fujio , Iyi Nobuo , Sasaki Takayoshi
Published: January 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: A 3D Metal Halide Framework in the Organic—Inorganic Compound (H3N(CH2)2SS (CH2)2NH3) 3Pb5I16.
Authors: Louvain Nicolas , Mercier Nicolas
Published: January 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Slow‐Proton Dynamics within a Zirconium‐Containing Sandwich‐Like Complex Based on the Trivacant Anion α‐[SiW9O34]10‐ — Synthesis, Structure and NMR Spectroscopy.
Authors: Leclerc‐Laronze Nathalie , Marrot Jerome , Haouas Mohamed , Taulelle Francis , Cadot Emmanuel
Published: January 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Synthesis and Characterization of Metal Tungstates by Novel Solid‐State Metathetic Approach.
Authors: Parhi Purnendu , Karthik T. N. , Manivannan V.
Published: January 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: The Influence of the Amine Concentration onto Product Formation: Crystal Structures, Thermal Stability and Spectroscopic Properties of Two New Manganese Thiostannates Obtained under Solvothermal Conditions.
Authors: Pienack Nicole , Naether Christian , Bensch Wolfgang
Published: January 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Residual Dipolar Coupling (RDCs) in Organic Structure Determination.
Authors: Thiele Christina M.
Published: January 2009

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.