bluuebunny/crossref_metadata_2025 huggingface dataset:
Metabolic Radiolabeling of Animal Cell Glycoconjugates
Authors: Diaz Sandra , Varki Ajit
Published: July 2009

Useful information about glycoconjugates can be obtained by labeling their aglycone (noncarbohydrate) portions—e.g., labeling proteins with radioactive amino acids—and then using techniques described elsewhere in this chapter to infer the presence, type, and nature of glycan chains. This unit describes metabolic labeling techniques that provide more specific information about the structure, sequence, and distribution of the sugar chains of glycoconjugates. Following metabolic labeling, the radioactive glycoconjugate of interest is isolated, individual glycosylation sites are identified and separated if necessary, and the labeled glycans are subjected to structural analysis. Curr. Protoc. Mol. Biol. 87:17.4.1‐17.4.15. © 2009 by John Wiley & Sons, Inc.
Resources for Small Regulatory RNAs
Authors: Bell George W. , Lewitter Fran
Published: July 2009

In the past fifteen years, new classes of regulatory RNAs have been discovered, previously hidden in the transcriptome mostly due to their small size. These small regulatory RNAs include small interfering RNAs (siRNAs), microRNAs (miRNAs), and Piwi‐interacting RNAs (piRNAs). Numerous databases have been developed to store information about these small regulatory RNAs, and many tools have been developed to work with the data. This overview introduces the reader to the many resources available for working with small regulatory RNAs. Curr. Protoc. Mol. Biol. 87:19.8.1‐19.8.13. © 2009 by John Wiley & Sons, Inc.
Fundamentals of Acoustic Cytometry
Authors: Ward Michael , Turner Patrick , DeJohn Marc , Kaduchak Gregory
Published: July 2009

Acoustic cytometry is a new technology that replaces or partly replaces hydrodynamic focusing of cells or particles with focusing derived from acoustic radiation pressure forces. It offers new possibilities for improving current flow cytometry assays and creating new ones. To take full advantage of these possibilities, it is necessary to understand the fundamental benefits and limitations of acoustic focusing as employed in flow cytometry analysis, either as a substitute for hydrodynamic focusing or in combination with it. Curr. Protoc. Cytom. 49:1.22.1‐1.22.12. © 2009 by John Wiley & Sons, Inc.
Detection of Extracellular Phosphatase Activity of Heterotrophic Prokaryotes at the Single‐Cell Level by Flow Cytometry
Authors: Duhamel Solange , Gregori Gerald , Wambeke France Van , Nedoma Jiří
Published: July 2009

Monitoring cell activity using substrates, which turn fluorescent due to biological activity, allows observing the presence and dynamics of sub‐populations, and provides a very valuable insight in ecological studies. The phosphatase substrate ELF97 phosphate (ELF‐P) is a useful tool to detect and quantify phosphatase activity (PA) of microorganisms at the single‐cell level. Most of the studies dealing with PA at the single‐cell level focus on autotrophic cells and only few concern heterotrophic prokaryotes (referred as bacteria in the text). While flow cytometry is a promising tool to assess the single‐cell analysis, only microscopy tools have been used until now to measure the ELF labeling associated with bacteria expressing PA. Therefore, we have developed a new protocol that enables the detection of ELF alcohol (ELFA), the product of ELF‐P hydrolysis, making possible the specific identification of bacteria showing PA using flow cytometry. Curr. Protoc. Cytom. 49:11.18.1‐11.18.8. © 2009 by John Wiley & Sons, Inc.
Simultaneous Optical Mapping of Intracellular Free Calcium and Action Potentials from Langendorff Perfused Hearts
Authors: Salama Guy , Hwang Seong‐min
Published: July 2009

The cardiac action potential (AP) controls the rise and fall of intracellular free Ca2+(Cai), and thus the amplitude and kinetics of force generation. Besides excitation‐contraction coupling, the reverse process where Caiinfluences the AP through Cai‐dependent ionic currents has been implicated as the mechanism underlying QT alternans and cardiac arrhythmias in heart failure, ischemia/reperfusion, cardiac myopathy, myocardial infarction, congenital and drug‐induced long QT syndrome, and ventricular fibrillation. The development of dual optical mapping at high spatial and temporal resolution provides a powerful tool to investigate the role of Caianomalies in eliciting cardiac arrhythmias. This unit describes experimental protocols to map APs and Caitransients from perfused hearts by labeling the heart with two fluorescent dyes, one to measure transmembrane potential (Vm), the other Caitransients. High spatial and temporal resolution is achieved by selecting Vm and Caiprobes with the same excitation but different emission wavelengths, to avoid cross‐talk and mechanical components.Curr. Protoc. Cytom. 49:12.17.1‐12.17.32. © 2009 by John Wiley & Sons, Inc.
Heterogeneous palladium–cobalt bimetal catalyst for the oxidative carbonylation of bisphenol A to polycarbonate
Authors: Okamoto Masaya , Sugiyama Jun‐ichi
Published: July 2009

Polycarbonates (PCs) were prepared by the oxidative carbonylation of bisphenol A and carbon monoxide with a hydrotalcite‐supported Pd–Co complex, a Pd–Co–poly(4‐vinylpyridine) complex [Pd–Co–(p‐4vpy)], a Pd–Co–polystyrene‐supported triphenylphosphine complex (Pd–Co–PS‐TPP), or a Pd–Co–polyvinylpyrrolidone complex (Pd–Co–pvp) as a heterogeneous Pd–Co bimetal catalyst to separate the PC solution and the Pd–Co bimetal catalyst after the reaction. Propylene carbonate was used as a halogen‐free solvent. Pd–Co–(p‐4vpy) and Pd–Co–PS‐TPP showed recycling potential, whereas Pd–Co–pvp, though not having recycling potential, yielded a high turnover number with a maximum of 1462. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Improvement of Targeted Gene Delivery to Human Cancer Cells by a Novel Trifunctional Crosslinker
Authors: Shiota Maki , Shamsur Lahman , Kawahara Shun‐ichi , Wadhwa Renu , Ikeda Yutaka
Published: July 2009

A facile method for the construction of an immunoconjugate which displays targeting ligands, such as antibody fragments, with a high density is reported. For this purpose, we synthesized a novel trifunctional crosslinking reagent. By the use of this reagent, ligands targeting the specific cell can be displayed on the surface of the drug carrier with a high density. In this study, we display HER2 (human epidermal growth‐factor receptor‐2) binding ligands on branched polyethylenimine (PEI), which can form polyplexes with plasmid DNA. Kinetic analysis of the binding to the extracellular domain of HER2 show the PEI displaying a high density of ligands binds to the target more strongly compared to the PEI displaying ligands at a low density. The increased density of HER2 ligands displayed on the gene carrier contributes to the improved transfection efficiency. This approach can be applied to other drug delivery systems, including liposome, micelle, and so on.
Preparation of C3‐Symmetric Homochiral syn‐Trisnorbornabenzenes through Regioselective Cyclotrimerization of Enantiopure Iodonorbornenes
Authors: Reza A. F. G. Masud , Higashibayashi Shuhei , Sakurai Hidehiro
Published: July 2009

C3‐symmetric homochiral (−)‐syn‐trisoxonorbornabenzene 1 possessing a rigid cup‐shaped structure was synthesized through a novel regioselective cyclotrimerization of enantiopure iodonorbornenes catalyzed by palladium nanoclusters. The yield of the cyclotrimerization was dependent on the stability of the palladium clusters, which was ascertained from the appearance and TEM images of the reaction mixtures. The efficient preparation of (−)‐syn‐1 was established in short steps, including the newly developed cyclotrimerization reaction. The thus‐prepared homochiral (−)‐syn‐1 can serve as a key intermediate for the synthesis of C3‐symmetric homochiral cup‐shaped molecules with a helical arrangement of substituents. Introduction of several types of substituents was well demonstrated through palladium‐catalyzed coupling reactions with the corresponding phosphate and triflate of (−)‐syn‐1.
Osmium‐Mediated Oxidative Cyclizations: A Study into the Range of Initiators That Facilitate Cyclization
Authors: Donohoe Timothy J. , Wheelhouse (née Gosby) Katherine M. P. , Lindsay‐Scott Peter J. , Churchill Gwydion H. , Connolly Matthew J. , Butterworth Sam , Glossop Paul A.
Published: July 2009

A general route to prepare substituted, saturated five‐membered heterocycles has been developed. The application of a wide range of starting materials to the osmium‐catalyzed oxidative cyclization reaction is described. Diols, hydroxy‐amides, hydroxy‐sulfonamides, and carbamates all cyclize in moderate to excellent yields to give cis‐tetrahydrofurans and pyrrolidines, depending upon the position of the heteroatoms in the starting materials. These cyclizations all proceed with near total selectivity for the cis‐heterocycles, and with stereospecific introduction of a hydroxy group adjacent to the ring. Moreover, routes to enantiopure starting materials are described, which give enantiopure products upon cyclization. Catalyst loadings of as low as one mol percent have been successfully employed for this transformation.
A simple approach to robustD‐stability analysis for uncertain singular delay systems
Authors: Lu Renquan , Su Hongye , Chu Jian , Xue Anke
Published: July 2009

This note presents a simple approach to analyze robustD‐stability for uncertain continuous‐time singular systems with state delay and structured uncertainties. Sufficient conditions, which are computationally simple, and need not calculate the eigenvalues of the system, are proposed to ensure that the uncertain continuous‐time singular delay system is regular, impulse free andD‐stable, that is, all its finite poles are located within a specified disk. Two numerical examples are given to demonstrate the application of the proposed method. Copyright © 2009 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Lysozyme‐lysozyme self‐interactions as assessed by the osmotic second virial coefficient: Impact for physical protein stabilization
Authors: Le Brun Virginie , Friess Wolfgang , Schultz‐Fademrecht Torsten , Muehlau Silke , Garidel Patrick
Published: July 2009

The purpose of the presented study is to understand the physicochemical properties of proteins in aqueous solutions in order to identify solution conditions with reduced attractive protein‐protein interactions, to avoid the formation of protein aggregates and to increase protein solubility. This is assessed by measuring the osmotic second virial coefficient (B22), a parameter of solution non‐ideality, which is obtained using self‐interaction chromatography. The model protein is lysozyme. The influence of various solution conditions on B22 was investigated: protonation degree, ionic strength, pharmaceutical relevant excipients and combinations thereof. Under acidic solution conditions B22 is positive, favoring protein repulsion. A similar trend is observed for the variation of the NaCl concentration, showing that with increasing the ionic strength protein attraction is more likely. B22 decreases and becomes negative. Thus, solution conditions are obtained favoring attractive protein‐protein interactions. The B22 parameter also reflects, in general, the influence of the salts of the Hofmeister series with regard to their salting‐in/salting‐out effect. It is also shown that B22 correlates with protein solubility as well as physical protein stability.
Molecular facets of sphingolipids: Mediators of diseases
Authors: Ozbayraktar Fatma Betul Kavun , Ulgen Kutlu O.
Published: July 2009

Sphingolipids constitute a biologically active lipid class that is significantly important from both structural and regulatory aspects. The manipulation of sphingolipid metabolism is currently being studied as a novel strategy for cancer therapy. The basics of this therapeutic approach lie in the regulation property of sphingolipids on cellular processes, which are important in a cell's fate, such as cell proliferation, apoptosis, cell cycle arrest, senescence, and inflammation. Furthermore, the mutations in the enzymes catalyzing some specific reactions in the sphingolipid metabolism cause mortal lysosomal storage diseases like Fabry, Gaucher, Niemann‐Pick, Farber, Krabbe, and Metachromatic Leukodystrophy. Therefore, the alteration of the sphingolipid metabolic pathway determines the choice between life and death. Understanding the sphingolipid metabolism and regulation is significant for the development of new therapeutic approaches for all sphingolipid‐related diseases, as well as for cancer. An important feature of the sphingolipid metabolic pathway is the compartmentalization into endoplasmic reticulum, the Golgi apparatus, lysosome and plasma membrane, and this compartmentalization makes the transport of sphingolipids critical for proper functioning. This paper focuses on the structures, metabolic pathways, localization, transport mechanisms, and diseases of sphingolipids in Saccharomyces cerevisiae and humans, and provides the latest comprehensive information on sphingolipid research.
Adopting sustainable innovation: what makes consumers sign up to green electricity?
Authors: Ozaki Ritsuko
Published: July 2009

This paper investigates what encourages consumers to adopt a green electricity tariff. When people decide to adopt an innovation, such as green electricity, they consider not only functionality, usability, costs and intended outcomes, but also what the innovation means to them, for example, the way it reflects their identity, image, memberships, values and norms. The study reviews the theoretical frameworks of innovation adoption and consumption, and cognitive and normative behaviour, relevant to consumer adoption of pro‐environmental innovations, and develops a research framework. Through focus group discussions, a questionnaire survey with 103 respondents and an interview with 10 people, the study finds that consumers sympathetic to environmental issues do not necessarily adopt green electricity. This is due to lack of strong social norms and personal relevance, inconvenience of switching, uncertainty about the quality of green electricity and lack of accurate information. The implications of these findings for strategy, policy and future research are explored. Copyright © 2009 John Wiley & Sons, Ltd and ERP Environment.
Empirical analysis of determinants of adoption of proactive environmental strategies in India
Authors: Sangle Shirish
Published: July 2009

Proactive environmental strategies are beyond extant laws and it is important to understand why companies go beyond compliance. The paper discusses motivations behind their adoption of proactive environmental strategies in India. The research results show that institutional pressure is the most significant determinant of adoption of proactive environmental strategies. Other factors such as managerial attitude, business case of environmental investments and productivity enhancement initiatives are also significant. Based on the research findings, the paper proposes some important managerial implications in connection with adoption of proactive environmental strategies. Copyright © 2009 John Wiley & Sons, Ltd and ERP Environment.
Position‐Dependent Effects of Fluorinated Amino Acids on the Hydrophobic Core Formation of a Heterodimeric Coiled Coil
Authors: Salwiczek Mario , Samsonov Sergey , Vagt Toni , Nyakatura Elisabeth , Fleige Emanuel , Numata Jorge , Cölfen Helmut , Pisabarro M. Teresa , Koksch Beate
Published: July 2009

Systematic model investigations of the molecular interactions of fluorinated amino acids within native protein environments substantially improve our understanding of the unique properties of these building blocks. A rationally designed heterodimeric coiled coil peptide (VPE/VPK) and nine variants containing amino acids with variable fluorine content in either position a16 or d19 within the hydrophobic core were synthesized and used to evaluate the impact of fluorinated amino acid substitutions within different hydrophobic protein microenvironments. The structural and thermodynamic stability of the dimers were examined by applying both experimental (CD spectroscopy, FRET, and analytical ultracentrifugation) and theoretical (MD simulations and MM‐PBSA free energy calculations) methods. The coiled coil environment imposes position‐dependent conformations onto the fluorinated side chains and thus affects their packing and relative orientation towards their native interaction partners. We find evidence that such packing effects exert a significant influence on the contribution of fluorine‐induced polarity to coiled coil folding.
Neutral Pentacoordinate Silicon(IV) Complexes with Silicon–Chalcogen (S, Se, Te) Bonds
Authors: Theis Bastian , Metz Stefan , Burschka Christian , Bertermann Rüdiger , Maisch Stefan , Tacke Reinhold
Published: July 2009

The neutral pentacoordinate silicon(IV) complexes 1 (SiS2ONC skeleton), 2 (SiSeSONC), 3 (SiTeSONC), 6/9 (SiSe2O2C), 7 (SiSe2S2C), and 8/10 (SiSe4C) were synthesized and structurally characterized by using single‐crystal X‐ray diffraction and multinuclear solid‐state and solution‐state (except for 6–9) NMR spectroscopy. With the synthesis of compounds 1–3 and 6–10, it has been demonstrated that pentacoordinate silicon compounds with soft chalcogen ligand atoms (S, Se, Te) can be stable in the solid state and in solution.
Helical Chiral Pyridine N‐Oxides: A New Family of Asymmetric Catalysts
Authors: Chen Jinshui , Takenaka Norito
Published: July 2009

Optically active chiral alkyl chlorides are valuable compounds because of their bioactivity and versatile synthetic utility. Accordingly, the ring opening of epoxides with a chloride nucleophile stands as an important goal in asymmetric catalysis. We describe herein recent advances in the design and development of chiral pyridine N‐oxide catalysts for the enantioselective synthesis of chlorohydrins.
Is the Backbone Conformation of Cα‐Methyl Proline Restricted to a Single Region?
Authors: De Poli Matteo , Moretto Alessandro , Crisma Marco , Peggion Cristina , Formaggio Fernando , Kaptein Bernard , Broxterman Quirinus B. , Toniolo Claudio
Published: July 2009

Cα‐Methyl‐L‐proline, or L‐(αMe)Pro, is probably the most conformationally constrained α‐amino acid. In particular, its ω and ϕ torsion angles are restricted to about 180 and −60°, respectively, and only three ranges of values are theoretically available for ψ in mono‐ or longer peptides, namely, about −30° (cis′, 310/α‐helical structure), 60° (inverse γ turn), or 140° (trans′, poly(L‐Pro)n II structure). In this work, we examined the tendency of a number of Nα‐acyl dipeptide N′‐alkylamides of the type RCO‐(αMe)Pro‐Xxx‐NHR′ or RCO‐Xxx‐(αMe)Pro‐NHR′, in which Xxx is L (or D)‐Ala, Aib (α‐aminoisoburyric acid), or L (or D)‐(αMe)Pro, long enough to fold into intramolecularly hydrogen‐bonded γ or β turns. The results are compared with those obtained for the corresponding dipeptides based on Pro, a well‐known turn‐forming residue. For the crystal‐state 3D‐structural analysis we used X‐ray diffraction, whereas our solution conformational analysis was heavily based on the FTIR absorption and 1H and 13C NMR spectroscopy techniques. We conclude that (αMe)Pro is able to explore both trans′ and cis′ ψ areas of the conformational space, but in (αMe)Pro the latter is overwhelmingly more populated, in marked contrast to the Pro preference. This finding is a clear indication that in (αMe)Pro the major 3D‐structural determinant is the Cα‐methyl group. The circular dichroism (CD) signature of a peptide type III′ β‐turn conformation is also proposed.
Dihydroxyacetone Phosphate Aldolase Catalyzed Synthesis of Structurally Diverse Polyhydroxylated Pyrrolidine Derivatives and Evaluation of their Glycosidase Inhibitory Properties
Authors: Calveras Jordi , Egido‐Gabás Meritxell , Gómez Livia , Casas Josefina , Parella Teodor , Joglar Jesús , Bujons Jordi , Clapés Pere
Published: July 2009

The chemoenzymatic synthesis of a collection of pyrrolidine‐type iminosugars generated by the aldol addition of dihydroxyacetone phosphate (DHAP) to C‐α‐substituted N‐Cbz‐2‐aminoaldehydes derivatives, catalyzed by DHAP aldolases is reported. L‐Fuculose‐1‐phosphate aldolase (FucA) and L‐rhamnulose‐1‐phosphate aldolase (RhuA) from E. coli were used as biocatalysts to generate configurational diversity on the iminosugars. Alkyl linear substitutions at C‐α were well tolerated by FucA catalyst (i.e., 40–70 % conversions to aldol adduct), whereas no product was observed with C‐α‐alkyl branched substitutions, except for dimethyl and benzyl substitutions (20 %). RhuA was the most versatile biocatalyst: C‐α‐alkyl linear groups gave the highest conversions to aldol adducts (60–99 %), while the C‐α‐alkyl branched ones gave moderate to good conversions (50–80 %), with the exception of dimethyl and benzyl substituents (20 %). FucA was the most stereoselective biocatalyst (90–100 % anti (3R,4R) adduct). RhuA was highly stereoselective with (S)‐N‐Cbz‐2‐aminoaldehydes (90–100 % syn (i.e., 3R,4S) adduct), whereas those with R configuration gave mixtures of anti/syn adducts. For iPr and iBu substituents, RhuA furnished the anti adduct (i.e., FucA stereochemistry) with high stereoselectivity. Molecular models of aldol products with iPr and iBu substituents and as complexes with the RhuA active site suggest that the anti adducts could be kinetically preferred, while the syn adducts would be the equilibrium products. The polyhydroxylated pyrrolidines generated were tested as inhibitors against seven glycosidases. Among them, good inhibitors of α‐L‐fucosidase (IC50=1–20 μM), moderate of α‐L‐rhamnosidase (IC50=7–150 μM), and weak of α‐D‐mannosidase (IC50=80–400 μM) were identified. The apparent inhibition constant values (Ki) were calculated for the most relevant inhibitors and computational docking studies were performed to understand both their binding capacity and the mode of interaction with the glycosidases.
Adaptive workflow processing and execution in Pegasus
Authors: Lee Kevin , Paton Norman W. , Sakellariou Rizos , Deelman Ewa , Fernandes Alvaro A. A. , Mehta Gaurang
Published: July 2009

Workflows are widely used in applications that require coordinated use of computational resources. Workflow definition languages typically abstract over some aspects of the way in which a workflow is to be executed, such as the level of parallelism to be used or the physical resources to be deployed. As a result, a workflow management system has the responsibility of establishing how best to execute a workflow given the available resources. The Pegasus workflow management system compiles abstract workflows into concrete execution plans, and has been widely used in large‐scale e‐Science applications. This paper describes an extension to Pegasus whereby resource allocation decisions are revised during workflow evaluation, in the light of feedback on the performance of jobs at runtime. The contributions of this paper include: (i) a description of how adaptive processing has been retrofitted to an existing workflow management system; (ii) a scheduling algorithm that allocates resources based on runtime performance; and (iii) an experimental evaluation of the resulting infrastructure using grid middleware over clusters. Copyright © 2009 John Wiley & Sons, Ltd.
A Vibrational Raman Optical Activity Study of 1,1′‐Binaphthyl Derivatives
Authors: Liégeois Vincent
Published: July 2009

The Raman polarized and vibrational Raman optical activity (VROA) backward spectra are simulated for a series of 2,2′‐substituted 1,1′‐binaphthyl compounds presenting a variety of torsion angles between the two naphthalene rings. The substitution prevents free rotation along this torsion angle and the chirality of these compounds is thus called atropisomerism. However, the rotation is not completely frozen so that two different conformations, namely cisoid and transoid, are found and their Raman and VROA signatures are studied. As expected, the Raman spectra are not very sensitive whereas the VROA spectra present more complex patterns, which evolve as a function of the torsion angle between the two naphthalene groups. In particular, our analysis shows that some modes can be used as a probe for the determination of the torsion angle of these molecules in solution. The contributions of both invariants to the VROA backward intensity are also assessed.
CX⋅⋅⋅O Halogen Bonding: Interactions of Trifluoromethyl Halides with Dimethyl Ether
Authors: Hauchecorne Dieter , Szostak Roman , Herrebout Wouter A. , van der Veken Benjamin J.
Published: July 2009

The formation of weakly bound molecular complexes between dimethyl ether (DME) and the trifluoromethyl halides CF3Cl, CF3Br and CF3I dissolved in liquid argon and in liquid krypton is investigated, using Raman and FTIR spectroscopy. For all halides evidence is found for the formation of CX⋅⋅⋅O halogen‐bonded 1:1 complexes. At higher concentrations of CF3Br, a weak absorption due to a 1:2 complex is also observed. Using spectra recorded at temperatures between 87 and 125 K, the complexation enthalpies for the complexes are determined to be −6.8(3) kJ mol−1 (DME⋅CF3Cl), −10.2(1) kJ mol−1 (DME⋅CF3Br), −15.5(1) kJ mol−1 (DME⋅CF3I), and −17.8(5) kJ mol−1 [DME(⋅CF3Br)2]. Structural and spectral information on the complexes is obtained from ab initio calculations at the MP2/ 6‐311++G(d,p) and MP2/6‐311++G(d,p)+LanL2DZ* levels. By applying Monte Carlo free energy perturbation calculations to account for the solvent influences, and statistical thermodynamics to estimate the zero‐point vibrational and thermal influences, the ab initio complexation energies are converted into complexation enthalpies for the solutions in liquid argon. The resulting values are compared with the experimental data deduced from the cryosolutions.
Geometric Model Describing the Banded Morphology of Particle Films Formed by Convective Assembly
Authors: Lee J. Alex , Reibel Kayla , Snyder Mark A. , Scriven L. E. , Tsapatsis Michael
Published: July 2009

Nanoparticle films coated on smooth substrates by convective assembly from dilute suspensions in dip‐coating configuration are known to have discrete film morphologies. Specifically, the film morphology is characterized by alternating bands of densely packed particles and bands of bare substrate. Convective assembly is a frontal film‐growth process that occurs at the three‐phase contact line formed by the substrate, the suspension in which it is submersed, and the surrounding air. The bands are parallel to this contact line and can be either monolayered or multilayered. Monolayered bands result whenever the substrate is withdrawn from the suspension at a rate too high for particles to assemble into a continuous film. We report a new insight to the mechanism behind this banding phenomenon, namely, that inter‐band spacing is strongly influenced by the constituent particle size. We therefore propose a geometric model relating the inter‐band spacing to the particle size. By making banded films with systematically varied particle sizes (silica/zeolite, 20 to 500 nm), we are able to quantitatively validate our model. Furthermore, the model correctly predicts that multilayered banded films have higher inter‐band spacings than monolayered banded films comprising the same particles.
Nanowire‐Based Polypyrrole Hierarchical Structures Synthesized by a Two‐Step Electrochemical Method
Authors: Ge Dongtao , Huang Sanqing , Qi Rucai , Mu Jing , Shen Yuqing , Shi Wei
Published: July 2009

A simple two‐step electrochemical method is proposed for the synthesis of nanowire‐based polypyrrole hierarchical structures. In the first step, microstructured polypyrrole films are prepared by electropolymerization. Then, polypyrrole nanowires are electrodeposited on the surface of the as‐synthesized microstructured polypyrrole films. As a result, hierarchical structures of polypyrrole nanowires on polypyrrole microstructures are obtained. The surface wettabilities of the resulting nanowire‐based polypyrrole hierarchical structures are examined. It is expected that this two‐step method can be developed into a versatile route to produce nanowire‐based polypyrrole hierarchical structures with different morphologies and surface properties.
A reversed‐phase high‐performance liquid chromatography method for bovine serum albumin assay in pharmaceutical dosage forms and protein/antigen delivery systems
Authors: Hamidi Mehrdad , Zarei Najmeh
Published: July 2009

Bovine serum albumin (BSA) is among the most widely used proteins in protein formulations as well as in the development of novel delivery systems as a typical model for therapeutic/diagnostic proteins and the new versions of vaccines. The development of reliable and easily available assay methods for quantitation of this protein would therefore play a crucial role in these types of studies. A simple gradient reversed‐phase high‐performance liquid chromatography with ultra‐violet detection (HPLC‐UV) method has been developed for quantitation of BSA in dosage forms and protein delivery systems. The method produced linear responses throughout the wide BSA concentration range of 1 to 100 µ g/mL. The average within‐run and between‐run variations of the method within the linear concentration range of BSA were 2.46% and 2.20%, respectively, with accuracies of 104.49% and 104.58% for within‐run and between‐run samples, respectively. The limits of detection (LOD) and quantitation (LOQ) of the method were 0.5 and 1 µg/mL, respectively. The method showed acceptable system suitability indices, which enabled us to use it successfully during our particulate vaccine delivery research project. Copyright © 2009 John Wiley & Sons, Ltd.
Assignment of the Absolute Configuration ofConcentricolide– Absolute Configuration Determination of Its Bioactive Analogs Using DFT Methods
Authors: Ren Jie , Jiang Ju‐Xing , Li Liang‐Bo , Liao Tou‐Geng , Tian Ren‐Rong , Chen Xu‐lin , Jiang Si‐Ping , Pittman Charles U. , Zhu Hua‐Jie
Published: July 2009

The configuration ofconcentricolidewas assigned as (S). The configuration of its three analogs, which have anti‐HIV‐1 activity, were predicted by optical rotation values obtained by the B3LYP/aug‐cc‐pVDZ//B3LYP/6‐31+G(d) and B3LYP/aug‐cc‐pVDZ//MP2/6‐311+G(d) methods. The two methods predict very close optical rotation magnitudes for all three chiral analogs ofconcentricolide. The two methods were applied in optical rotation predictions for seven otherconcentricolideanalogs. Circular dichroism calculations were performed for four of the seven analogs at the B3LYP/aug‐cc‐pVDZ level.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
On modeling cluster maxima with applications to ozone data from Mexico City
Authors: Villaseñor‐Alva José A. , González‐Estrada Elizabeth
Published: July 2009

The study of the probability behavior of concentrations of air pollutants in the atmosphere is of great interest in order to take actions in favor of human health protection in large cities. This work proposes a parametric distributional model for the daily cluster maxima of concentrations exceeding a threshold, taking into consideration the dependence within the cluster. This model also provides a family of joint probability distributions for the maximum and the cluster size variables, which allows the study for prediction purposes of the conditional cluster size mean given that the cluster maximum does not exceed a particular value. The parameter estimation problem is discussed and a data set containing Mexico City ozone levels from the Summer seasons of years 2003 to 2007 is analyzed. Copyright © 2009 John Wiley & Sons, Ltd.
Modelling flow to and inundation of the Macquarie Marshes in arid Australia
Authors: Ren Shiquan , Kingsford Richard T. , Thomas Rachael F.
Published: July 2009

Building of dams and subsequent abstraction upstream of rivers significantly affects major wetland systems. Knowledge of anthropogenic impacts of river regulation, relative to stochastic variation, is essential if managers are able to adequately manage flows to wetlands. We built annual flow and inundated area models for the Macquarie Marshes supplied by the Macquarie River, based on available annual rainfall data (1879–2006). We used LOESS, the flexible local polynomial regression method, ideal for modelling complex processes where no theoretical models exist. To compare effects of river regulation and abstraction, we developed two models, before river regulation (‘natural’ or ‘unregulated’) and after river regulation (‘regulated’). The division was when Burrendong dam, the most significant regulatory structure affecting flows, was built in 1963 and completed in 1967. After this point, water was diverted upstream, predominantly for irrigation. We developed ‘natural’ and ‘regulated’ flow models for three flow gauges Dubbo, Warren and Oxley based on annual rainfall at rainfall stations in the upper catchment and flow, and then inundated area models based on flow and local rainfall to fit annual inundated area data (1979–2006) in the Macquarie Marshes, using LOESS and leave‐one‐out samples without overfitting. We evaluated the performance of the proposed models and used these models to predict annual flows and inundated areas from 1879 to 2006. Comparison was done in terms of ‘natural’ and ‘regulated’ data using Kolmogorov–Smirnov test, identifying significant reductions in flow and wetland area. Copyright © 2009 John Wiley & Sons, Ltd.
Statistics for spatial functional data: some recent contributions
Authors: Delicado P. , Giraldo R. , Comas C. , Mateu J.
Published: July 2009

Functional data analysis (FDA) is a relatively new branch in statistics. Experiments where a complete function is observed for each individual give rise to functional data. In this work we focus on the case of functional data presenting spatial dependence. The three classic types of spatial data structures (geostatistical data, point patterns, and areal data) can be combined with functional data as it is shown in the examples of each situation provided here. We also review some contributions in the literature on spatial functional data. Copyright © 2009 John Wiley & Sons, Ltd.
Nonparametric test for separability of spatio‐temporal processes
Authors: Crujeiras Rosa M. , Fernández‐Casal Rubén , González‐Manteiga Wenceslao
Published: July 2009

Spatio‐temporal correlated data are quite common in many fields, such as ecology, methereology or environmental science. In this situation, it is important to check the existence of spatio‐temporal interactions or on the contrary, if the spatial and temporal dependence components can be modelled independently. In this work, we propose a testing technique for detecting separability in the spatio‐temporal dependence structure. Our approach is based on the representation of the log‐periodogram as the response variable in a regression model. Within this context, separability can be interpreted as additivity in spatial and temporal frequency components. We also provide some simulation results comparing the performance of the asymptotic test with a marginal integration and a backfitting approach. The testing method is also applied to a real‐data case. Copyright © 2009 John Wiley & Sons, Ltd.
Compound optimal spatial designs
Authors: Müller Werner G. , Stehlík Milan
Published: July 2009

A single purpose design may be quite inefficient for handling a real‐life problem. Therefore, we often need to incorporate more than one design criterion and a common approach is simply to construct a weighted average, which may depend upon different information matrices. Designs based upon this method have been termed compound designs. The need to satisfy more than one design criterion is particularly relevant in the context of random fields. It is evident that for precise universal kriging it is important not only to efficiently estimate the spatial trend parameters, but also the parameters of the variogram or covariance function. Both tasks could for instance be comprised by applying corresponding design criteria and constructing a compound design from there. Modern techniques for such first and second order characteristics will be suggested and reviewed in the presentation. A new hybrid stochastic exchange type optimization algorithm is proposed and an illustrating example of the design of a water‐quality monitoring network is provided. Copyright © 2009 John Wiley & Sons, Ltd.
Spatio‐temporal modeling of mortality risks using penalized splines
Authors: Ugarte M. D. , Goicoa T. , Militino A. F.
Published: July 2009

Analyzing the temporal evolution of the geographical distribution of mortality (or incidence) risks is an important area of research in disease mapping. It might help to better determining the risk factors involved in the studied disease, and to address important epidemiological questions about the stability of the estimated patterns of disease. Traditionally, risk smoothing is carried out using conditional autoregressive (CAR) models but very recently, penalized splines have also been considered in an Empirical Bayes (EB) spatial context to estimate large‐scale spatial trends together with region random effects. In this paper, penalized splines for smoothing risks in both the spatial and the temporal dimensions will be applied. The mean squared error (MSE) of the log‐risk predictor will be derived allowing for constructing confidence intervals for the risks. To illustrate the procedure mortality data due to brain cancer in continental Spain over the period 1996–;2005 are analyzed. Copyright © 2009 John Wiley & Sons, Ltd.
Derivation of sample oriented quantile function using maximum entropy and self‐determined probability weighted moments
Authors: Deng Jian , Pandey M. D.
Published: July 2009

The paper proposes a new distribution free method for deriving the quantile function of a non‐negative random variable using the principle of maximum entropy (MaxEnt) subject to constraints in terms of the self‐determined probability‐weighted moments estimated from observed sample data. The principle of MaxEnt constrained by probability weighted moments (PWMs) was utilized to estimate the quantile function. For correct estimation of a quantile function, outliers must be rationally considered in the analysis. However, conventional PWM was criticized for assigning non‐exceedance probabilities to sample points based on only their rank number in an ordered series rather than the magnitude of the points themselves, hereby being unable to satisfactorily accommodate outlier in a finite sample. The difficulty in obtaining accurate PWM estimates from samples has been the main impediment to the application of the MaxEnt Principle in extreme quantile estimation. This paper is an attempt to circumvent this difficulty by the use of self‐determined probability‐weighted moments, which are completely decided by the distribution itself and sample data's magnitude. By interpreting the SD‐PWM as moment of quantile function, the paper derives a more rigorous quantile function using MaxEnt principle, which is extraordinarily suitable for cases with small samples containing outliers. An efficient algorithm is presented to estimate the unknown parameters of this sample oriented MaxEnt QF. Comparative studies and numerical analysis are performed to assess the accuracy of the proposed QF estimation method. Copyright © 2009 John Wiley & Sons, Ltd.
Spatio‐temporal variations of hyporheic flow in a riffle‐step‐pool sequence
Authors: Käser Daniel H. , Binley Andrew , Heathwaite A. Louise , Krause Stefan
Published: July 2009

Subsurface flow in streambeds can vary at different scales in time and space. Recognizing this variability is critical for understanding biogeochemical and ecological processes associated with the hyporheic zone. The aim of this study was to examine the variability of hydraulic conductivity (K), vertical hydraulic gradients (VHGs), and subsurface fluxes, over a riffle–step–pool sequence and at a high spatio‐temporal resolution. A 20 m reach was equipped with a network of piezometers in order to determine the distribution of VHGs and K. During a summer month, temporal variations of VHGs were regularly surveyed and, for a subset of piezometers, the water level was automatically recorded at 15 min intervals by logging pressure transducers. Additionally, point‐dilution tests were carried out on the same subset of piezometers. Whereas the distribution of vertical fluxes can be derived from K and VHG values, point‐dilution tests allow for the estimation of horizontal fluxes where no VHG is detectable. Results indicate that, spatially, VHGs switched from upwelling to downwelling across lateral as well as longitudinal sections of the channel. Vertical fluxes appeared spatially more homogeneous than VHGs, suggesting that the latter can be a poor indicator of the intensity of flow. Finally, during flow events, some VHGs showed little or no fluctuations; this was interpreted as the result of a pressure wave propagating from upstream through highly diffusive alluvial sediments. Copyright © 2009 John Wiley & Sons, Ltd.
Network ties and mean lies: a relational approach to relational aggression
Authors: Neal Jennifer Watling
Published: July 2009

The current study considers how the structure of peer networks facilitates or constrains children's opportunities to engage in relationally aggressive behaviors such as social exclusion and rumor spreading. Specifically, the influence of two network features, centrality and density, on relational aggression are explored using grade‐level behavioral and social network data collected on a demographically diverse sample of 144 third through eighth grade urban elementary school students. As hypothesized, these network features influenced levels of teacher‐rated and peer‐nominated relational aggression beyond the effects of demographic characteristics (i.e., gender and grade). Results revealed that relational aggression is influenced not only by who children are, but also by where they are located in the peer context. Implications for future research and intervention are offered. © 2009 Wiley Periodicals, Inc.
Highly efficient and organic nitrogen‐containing cation‐promoted aerobic oxidation of alkylaromatics in the presence of N‐hydroxyphthalimide
Authors: Tong Xinli , Xu Jie , Miao Hong , Gao Jin , Sun Zhiqiang , Zhang Wei
Published: July 2009

BACKGROUD: Direct oxidation of alkylaromatics to the corresponding aromatic ketone is an important process in the manufacture of perfumes, pharmaceuticals, flavors, dyes and agrochemicals. For example, tetralin is oxidized to produce 1‐tetralinone, which is a key intermediate in the commercial production of 1‐naphthol, 2‐hydroxy‐1‐tetralone, aureolic acid antibiotics and other pharmaceuticals.

RESULTS: In this investigation, it was found that alkylaromatics could be efficiently and selectively oxidized to the corresponding aromatic ketones when methyl violet was employed as a promotor in the presence of N‐hydroxyphthalimide (NHPI); tetralin was oxidized with 89% conversion and 76% selectivity to 1‐tetralinone under 0.3 MPa of O2 at 75 °C for 2.5 h. The effects of temperature, oxygen pressure, reaction time and additive inclusion were studied in detail. A possible reaction mechanism for tetralin oxidation has been proposed.

CONCLUSION: It was demonstrated that methyl violet could efficiently promote the aerobic oxidation of alkylaromatics in the presence of NHPI under mild conditions. Further investigations indicated that the nitrogen cation had a crucial promotion effect in the oxidation process. Copyright © 2009 Society of Chemical Industry
Synthesis of [3‐13C]‐, [4‐13C]‐ and [11‐13C]‐porphobilinogen
Authors: Dawadi Prativa B. S. , Schulten Els A. M. , Lugtenburg Johan
Published: July 2009

[4‐13C]‐porphobilinogen 1a, [3‐13C]‐porphobilinogen 1b and [11‐13C]‐porphobilinogen 1c are prepared from [1‐13C]‐3‐(tetrahydropyran‐2′‐yloxy)‐propionaldehyde 2a, methyl [4‐13C]‐4‐nitrobutyrate 3b and [1‐13C]‐isocyanoacetonitrile 5c, respectively. The building blocks 2, 3 and 5 can be prepared efficiently in any isotopomeric form. Via base‐catalyzed condensation of these building blocks porphobilinogen can be enriched with 13C and 15N stable isotopes at any position and combination of positions. Copyright © 2009 John Wiley & Sons, Ltd.
The first synthesis of [11C]oseltamivir: a tool for elucidating the relationship between Tamiflu and its adverse effects on the central nervous system
Authors: Arai Takuya , Konno Fujiko , Ogawa Masanao , Zhang Ming‐Rong , Suzuki Kazutoshi
Published: July 2009

Oseltamivir phosphate (Tamiflu®) is an anti‐influenza drug approved in many countries. Recently, in Japan, adverse effects on the central nervous system have been reported in younger patients administrated with Tamiflu. As a tool for elucidating the relationship between Tamiflu and its adverse effects, 11C‐labeled oseltamivir was synthesized through a two‐step reaction involving [11C]acetylation with [1‐11C]acetyl chloride. Starting from approximately 37.0 GBq of [11C]CO2, 1.2–1.8 GBq (n=5) of [11C]oseltamivir was obtained at the end of synthesis (EOS) 36–39 min after the end of bombardment. Radiochemical purity and specific activity were greater than 98% and 2.7–6.3 GBq/µmol at EOS, respectively. Copyright © 2009 John Wiley & Sons, Ltd.
Synthesis of three isotopically labeled versions and a metabolite of Aurora A kinase inhibitor
Authors: Li Yuexian , Prakash Shimoga R.
Published: July 2009

Sodium ring‐[14C]‐4‐[[9‐chloro‐7‐(2,6‐difluorophenyl)‐5H‐pyrimido[5,4‐d][2]benzazepin‐2‐yl]amino]‐benzoate (1A, MLN8054), an Aurora A kinase inhibitor, was synthesized from [14C]‐cyanamide in two steps in an overall radiochemical yield of 7%. The intermediate, [14C]‐4‐guanidinobenzoic acid, was prepared by coupling [14C]‐cyanamide with 4‐aminobenzoic acid. Sodium carboxyl‐[14C]‐4‐[[9‐chloro‐7‐(2,6‐difluorophenyl)‐5H‐pyrimido[5,4‐d][2]benzazepin‐2‐yl]amino]‐benzoate (1B) was synthesized from carboxyl‐[14C]‐4‐guanidinobenzoic acid in one step in a radiochemical yield of 35%. [D4,15N]‐4‐[[9‐chloro‐7‐(2,6‐difluorophenyl)‐5H‐pyrimido[5,4‐d][2]benzazepin‐2‐yl]amino]‐benzoic acid (1C) was synthesized from [15N2]‐cyanamide and [D4]‐4‐aminobenzoic acid in two steps in an overall yield of 37%. The major metabolite, β‐acyl glucuronide of 4‐[[9‐chloro‐7‐(2,6‐difluorophenyl)‐5H‐pyrimido[5,4‐d][2]benzazepin‐2‐yl]amino]‐benzoic acid (14), was synthesized from D‐glucuronic acid in three steps in an overall yield of 1%. The key intermediate for synthesis of glucuronide was prepared by HATU catalyzed coupling of 4‐[[9‐chloro‐7‐(2,6‐difluorophenyl)‐5H‐pyrimido[5,4‐d][2]benzazepin‐2‐yl]amino]‐benzoic acid with allyl glucuronate. Copyright © 2009 John Wiley & Sons, Ltd.
Raman spectroscopy and security applications: the detection of explosives and precursors on clothing
Authors: Ali Esam M. A. , Edwards Howell G. M. , Scowen Ian J.
Published: July 2009

This study describes the application of confocal Raman microscopy to the detection and identification of explosives and their precursors in situ on undyed natural and synthetic fibres and coloured textile specimens. Raman spectra were obtained from explosives particles trapped between the fibres of the specimens. The explosives pentaerythritol tetranitrate (PETN), trinitrotoluene (TNT), and ammonium nitrate as well as the explosives precursors hexamethylenetetraamine (HMTA) and pentaerythritol were used in this study. Raman spectra were collected from explosives particles with maximum dimensions in the range 5–10 µm. Despite the presence of spectral bands arising from the natural and synthetic polymers and dyed textiles, the explosive substances could be identified by their characteristic Raman bands. Furthermore, Raman spectra were obtained from explosives particles trapped between highly fluorescent clothing fibres. Raman spectra of the explosive and explosive precursor substances on dyed and undyed clothing substrates were readily obtained in situ within 90 s without sample preparation and with no alteration of the evidential material. Copyright © 2009 John Wiley & Sons, Ltd.