bluuebunny/crossref_metadata_2025 huggingface dataset:
Desorption Electrospray Ionization Mass Spectrometry
Authors: Pasilis Sofie P.
Published: September 2010

Desorption electrospray ionization is an atmospheric pressure surface sampling/ionization technique for mass spectrometry. Desorption electrospray ionization consists of a pneumatically assisted electrospray ionization source, or emitter, held at a fixed angle above a sample surface. A high‐velocity spray consisting of charged solvent microdroplets in a gas stream emerges from the source and impacts the sample surface. The spray solubilizes any analyte molecules that are present and creates charged analyte‐containing secondary droplets that are drawn into the inlet of the mass spectrometer through an atmospheric pressure interface. Ionization may occur in a fashion similar to that involved in electrospray ionization, although other ionization mechanisms may also play a role. Analytes that can be detected using electrospray ionization mass spectrometry can also be detected using desorption electrospray ionization mass spectrometry. Desorption electrospray ionization can be used to rapidly sample surfaces ranging from living tissues to metal oxides for a diverse variety of analytes, and has been used for such important applications as direct determination of analytes present in complex matrices, analyses of biological tissues and forensically relevant materials, readout of thin‐layer chromatography plates, and chemical imaging. As in electrospray ionization, multiply‐charged ions are formed during desorption electrospray ionization, allowing for the detection of analytes having molecular weight ranges beyond the
m
/
z
range of the mass analyzer.
Using Scanning Probe Microscopy to Characterize Nanoparticles and Nanocrystals
Authors: Serem Wilson K. , Lusker Kathie L. , Garno Jayne C.
Published: September 2010

Inorganic synthesis and materials chemistry have made it possible to synthesize and tailor the properties of nanoparticles for diverse applications. Nanoparticles have been conjugated with DNA, peptides, and antibodies to generate nanoparticle bioconjugates with hybrid functionalities that are useful for a broad range of applications in bioanalytical assays, targeted drug delivery and nanotechnology. Concurrent with development of synthetic approaches for nanoparticles, new measurements have evolved using scanning probe microscopy (SPM), providing unprecedented resolution and measurement capabilities for characterizations of the morphology and certain properties of nanoparticles and nanocrystals. New measurement technologies with SPM are still being invented, and the tools of SPM have been widely implemented by researchers in both academia and industry. The incentive and primary advantage for SPM measurements are the capabilities of reaching atomic and molecular resolution. Local surface modification can also be accomplished with SPM‐based lithographies. In this article, recent applications of SPM for nanoscale measurements and nanofabrication with different systems of nanoparticles and nanocrystals are reviewed. Scanning probe measurements provide unprecedented resolution for characterizing nanomaterials to investigate physical, chemical, and biochemical properties at the nanoscale. The advantages and limitations of SPM are also discussed, with descriptions of the various imaging and lithography modes that have been applied for characterizing nanoparticles.
Operations Research in
A
ustralia
Authors: Kozan Erhan
Published: September 2010

The Australian Society for Operations Research Inc. has fostered the profession of OR in Australia since 1972 and has served as a platform for exchange of ideas between practitioners. The ASOR bulletin was founded in 1981 and its aims to provide news of ASOR activities, book reviews, Australian problem descriptions and solution approaches. ASOR organizes its national conference every two years to keep up to date with operations research issues in Australia and overseas. The ASOR official web‐site (
http://www.asor.org.au
) was set up in 2006 to present the latest information about the members. The society continues to serve as an important organization for operations researchers to communicate with each other and to reach out to other professional societies.
Brazilian Society of Operational Research
Authors: Parracho Sant'Anna Annibal
Published: September 2010

The Brazilian Society of Operational Research has been connecting researchers and enhancing the development of research in the area of operational research in Brazil since 1969. Among its accomplishments are counted the Brazilian Symposia on Operational Research, which have been held annually over the last four decades. The society is also responsible for the publication of scientific journals, among which the Pesquisa Operacional has also a long history of contribution for the development of science.
Chilean Institute of Operations Research
Authors: Gutierrez Juan , Parada Victor , Weber Richard
Published: September 2010

Operations research methods and applications have played a crucial role in the development of several Chilean industries as well as the government. This paper provides a brief overview of the history and current developments of the Chilean Institute of Operations Research, ICHIO.
OR/MSApplied to Cricket
Authors: Wright Mike
Published: September 2010

This paper article describes the sport of cricket and considers some of the key decisions that must be made. Decisions are shown to be important at many levels, including decisions for administrators, coaches, captains, and players. Many of the most important OR/MS studies from the literature are summarized. The topics covered include the Duckworth/Lewis method for determining winners of unfinished or shortened matches, the scheduling of fixtures and the match officials (“umpires”) and various strategic and tactical decisions.
Croatian Operational Research Society
Authors: Babić Zoran , Neralić Luka
Published: September 2010

The war against Croatia, which started in 1991, helped the formation of the national OR Society of Croatia. Also, organization of the first OR Conference KOI '91 in December 1991 was important in establishing the Croatian Operational Research Society (CRORS). From that time the Society has been organizing national OR conferences every two years. CRORS now consists of about a hundred active members who are mainly professors and assistants from the Croatian Universities, and most of them belong to faculties of economics. Most of are mathematicians by their formal education, but there are also a number of people who are economists or engineers.
Music and Operations Research
Authors: Chew Elaine , Raphael Christopher
Published: September 2010

The well‐known link between music and mathematics has increased in significance due to the explosion in digital music information. The importance of mathematical modeling of music problems and their computational solution has led to the emergence of the field of music information research. There exist a number of significant links between music and operations research (OR). This article surveys some of these research advances. Beginning with mathematical representations of music pitch and time structures, we give an overview of OR formulations of problems in music composition and improvisation. We touch upon a range of problems in the analysis of music structures and of expressive gestures, then give a deeper treatment of dynamic programming formulations and solutions of problems across a number of music topics.
Orbel, The Belgian Operations Research Society (
SOGESCI
‐
BVWB
)
Authors: Kunsch Pierre L.
Published: September 2010

This article presents information about the Belgian Operations Research Society. SOGESCI‐BVWB, known as ORBEL in short. It was founded in 1958, and it has about 120 members. It represents Belgium in EURO and IFORS, and has many links to other OR societies elsewhere in the world.
Pricing and Scheduling Decisions
Authors: Allon Gad
Published: September 2010

Service providers and manufacturers facing customers, who are sensitive to price and delay, use both pricing and scheduling mechanisms to improve their profitability or maximize the value of their system. We study the interplay between the pricing and scheduling decisions in a variety of settings, depending on the type of provider (a social planner, a monopolist, or oligopolies), the service setting (observable queue versus nonobservable), and the customer population (homogeneous or heterogeneous, segmented or unsegmented).
Simultaneous Ascending Auctions
Authors: Cramton Peter
Published: September 2010

The simultaneous ascending auction has proved to be a successful method of auctioning many related items. Simultaneous sale and ascending bids enable price discovery, which helps bidders build desirable packages of items. Although package bids are not allowed, the auction format does handle mild complementarities well. The auction design and its performance in practice are examined.
Description of the
F
rench Operational Research and Decision‐Aid Society:

Société
F
rançaise de Recherche Opérationnelle et d'aide À la Décision

(
ROADEF
)
Authors: Hudry Olivier
Published: September 2010

The French society of operational research and decision‐aid (ROADEF) was formed in 1998, with the aim of promoting, in France, all the activities related to the operational research and the decision‐aid in all the possible fields: teaching, research, industries, civil and military applications, and so on. This text describes the main features of the ROADEF: how and by whom it was formed, the composition of its successive boards, and its main activities. Among these, we emphasize the annual national meetings of the ROADEF, the topics of its working groups, the publications involving the society (including the two international journals
4OR, a Quarterly Journal of Operations Research
and
RAIRO‐Operations Research
), the Robert Faure prize, and the challenges organized by the ROADEF, sometimes in collaboration with the
Association of European Operational Research Societies
(EURO).
The Manufacturing and Service Operations Management (
MSOM
) Society
Authors: Olsen Tava
Published: September 2010

This article describes the Manufacturing and Service Operations Management (MSOM) Society. It gives a history of the society including a list of former presidents, a description of society governance, information on the society prizes and publications, and meeting information.
Supporting the Strategy Process: The Role of Operational Research/Management Science
Authors: O'Brien Frances
Published: September 2010

Operational research/management science (OR/MS) can support the core, strategic activities at the heart of every organization. This introductory review article begins by explaining what is meant by the terms strategy, strategic decisions, and issues. It then introduces the key characteristics of a strategy process before reviewing two sources of literature that together highlight a variety of tools that can be used to support different activities within the process. One of the key conclusions of this introductory article is that tools to support the strategy process can be drawn from both the OR/MS field as well as other academic disciplines such as the strategy field. A related conclusion is that employing multiple tools either individually or in combination is useful since they provide different but complementary insights into the decisions and issues under consideration. The article concludes with some potential future research directions in the OR/MS and strategy field.
Multimethodology
Authors: Mingers John
Published: September 2010

Within the discipline of operations research and management science, many methods and techniques have been developed. Initially, these were generally based on mathematical or computer models. However, it was found in practice, particularly with complex, “wicked” problems, that many aspects of the situation, especially those concerning peoples' viewpoints and values, could not be represented mathematically. This led to the development of a range of nonquantitative, “soft” methods, which were, nevertheless, rigorous and systemic. Examples are soft systems methodology (SSM), cognitive mapping, strategic choice analysis, and strategic assumption surfacing and testing (SAST).

The question then became, which method should be used when? However, rather than using just a single method, theory and practice have demonstrated that most complex problems are better tackled using a combination of methods, both “hard” and “soft.” This approach has been called
multimethodology
.
Luminescence Phenomena Involving Metal Enolates
Authors: Felinto Brito Hermi , Manoel Loureiro Malta Oscar , Claudia França Cunha Felinto Maria , Epaminondas de Sousa Teotonio Ercules
Published: September 2010

Introduction

Metal Enolates

Luminescence of Rare‐Earth Enolates

Luminescence Involvings,panddMetal Block Enolates

Applications

Acknowledgments
Thermochemical Considerations of Metal Enolates
Authors: Liebman Joel F. , Slayden Suzanne W.
Published: September 2010

Introduction

Group 1: Lithium, Sodium, Potassium, Rubidium and Cesium

Group 2: Beryllium, Magnesium, Calcium, Strontium and Barium

Group 13: Aluminum, Gallium, Indium and Thallium

Group 14: Tin and Lead

Group 11: Copper, Silver and Gold

Group 12: Zinc, Cadmium and Mercury

Group 3: Scandium, Yttrium and the Lanthanides

Actinides

Group 4: Titanium, Zirconium and Hafnium

Group 5: Vanadium, Niobium and Tantalum

Group 6: Chromium, Molybdenum and Tungsten

Group 7: Manganese and Rhenium

Group 8: Iron, Ruthenium and Osmium

Group 9: Cobalt, Rhodium and Iridium

Group 10: Nickel, Palladium and Platinum
Coordination Chemistry of Metal Enolato Complexes
Authors: Vicente José
Published: September 2010

Introduction

Enolato
Versus
2‐Oxoalkyl Coordination

Reactions of Enolato Complexes to give other Enolato Complexes

Aldol Reactions

Protonation Reactions

Coordination Chemistry of Phosphinoenolato Complexes

Coordination Chemistry of Metalafurans

Miscellaneous Reactions

Acknowledgments
Metal Enolates as Synthons in Organic Chemistry
Authors: Stolz Daniel , Kazmaier Uli
Published: September 2010

C

C
Bond Formation by α‐Substitution of Ketone Enolates

C

C
Bond Formation by Addition of Ketone Enolates to Carbonyl Groups

C

C
Bond Formation by
M
ichael Addition of Metal Enolates

Ester Enolates
Redox Chemistry and Electrochemistry of Metal Enolates
Authors: Pampaloni Guido , Zanello Piero
Published: September 2010

Introduction

Metal EnolatesMOCC

Simple β‐Diketonates

Functionalized β‐Diketonates

Polyketonates

Acknowledgments
Analytical Aspects of Metal Enolates
Authors: Harlev Eli , Bittner Shmuel , Zabicky Jacob
Published: September 2010

Introduction and Scope of the Chapter

Detection and Determination of Metal Enolates

Metal Enolates as Analytical Reagents and Aids
Metal Enolates in Polymer Science and Technology
Authors: Lecomte Philippe , Jérôme Robert
Published: September 2010

Introduction

Radical Polymerization

Polymerization of Nonfunctionalized Olefins

Polymerization of Lactones and Lactides

Anionic Polymerization of Methacrylates and Acrylates

Macromolecular Engineering and Enolates

Acknowledgments
Light‐Induced Chemistry of Oximes and Derivatives
Authors: D. Roth Heinz
Published: September 2010

Photoreactions of oximes have been known for 120 years. The earliest recognized reaction was geometric isomerization, which is still the most prominent oxime photoreaction; it proceeds via a ππ* triplet state. More than sixty years later the intriguing photo‐Beckmann rearrangement came to light, a C–C=N–O to O=C–N–C conversion, generating, for example, ɛ‐caprolactam from cyclohexanone ξιμɛ. The rearrangement proceeds via a ππ* singlet state forming an oxazirane intermediate; the oxazirane ring usually opens in stereospecific fashion. Detailed insight into the stereo‐ and regiochemistry of the rearrangement was gained from steroidal oximes, the most thoroughly investigated class of oximes.

Additional photoreactions of oximes or of their ethers and esters include: net loss of hydroxylamine generating carbonyl compounds; loss of water from aldoximes forming nitriles; conversion of ketoximes to nitriles by more complex mechanisms; photochemical O–H cleavage generating iminoxyl radicals, an interesting family of free radicals; N–O cleavage giving rise to iminyl radials, which undergo radical cyclizations. β,γ‐Unsaturated oximes undergo aza‐di‐π‐methane rearrangements, cyclize to oxazolines, and undergo further reorganizations. The palette of oxime reactions has been further enriched by triplet energy transfer or electron transfer sensitization; oximes serve as electron donors or acceptors.
Heterocycles from Hydroxylamines and Hydroxamic Acids
Authors: Katkevics Martins , Kukosha Tatyana , Lukevics Edmunds
Published: September 2010

Hydroxylamines and hydroxamic acids are polyfunctional organic molecules and several reactive intermediates can be generated from them, therefore they have found broad application in the synthesis of various nitrogen and oxygen containing heterocycles by means of nulceophilic substitution or addition, electrophilic intramolecular aromatic substitution, as well as [2+4] and [3+2] cycloaddition reactions. This chapter surveys synthesis of heterocycles from the title compounds highlighting some distinguished reaction mechanism aspects, regio‐ and stereo selectivity issues and experimental details. It is arranged according to the size and type of heterocycles that allows fast but also explanatory insight into synthesis of the particular cycles.
Hydroxylamine Analogs and Derivatives of Amino Acids. Aminooxy Acids
Authors: Zvilichovsky Gury
Published: September 2010

This chapter provides a review of researches in the field of aminooxy acids and related compounds. The first syntheses of aminooxy acids were described about 120 years ago. The first natural aminooxy acids and their derivatives, like canaline, canavanine and the antibiotic cycloserine, were discovered in the thirties and fifties of last century. Their first peptides were prepared in the sixties. In recent years this field gained increasing interest due to the special properties of peptides glycosides and glycopeptides containing aminooxy acids. These biomimetic compounds include aminooxy acids incorporated in biologically active macromolecules, either inside the chains or in terminal positions. The latter derivatives are used for ligation of functional groups resulting in biological probes, biosensors and and other useful devices. The free aminooxy group in such chains enables the facile prepration of bioconjugates, attachment to solid surfaces, modifications of recombinant proteins, preparing various vaccines and more. Peptides, proteins and glycopeptides containing an amidooxy bond exhibit interesting secondary, tertiary and quaternary structures. They reveal new folding properties, resulting in useful biomimetic foldamers for various applications.

This chapter includes up to date information on the synthesis, chemical and biological properties of aminooxy acids and their derivatives.
Phosphorus Derivatives of Hydroxylamines, Oximes and Hydroxamic Acids
Authors: Palacios Francisco , de los Santos Jesús M. , Vicario Javier , Alonso Concepción
Published: September 2010

This comprehensive chapter, organized in three different sections, includes new topics focused on preparation and synthetic applications of phosphorus functionalized hydroxylamines, oximes and hydroxamic acids. The first section comprises the synthesis of phosphorusO‐substituted hydroxylamines either through phosphorus‐oxygen or nitrogen‐oxygen single bond formation. The synthesis ofN‐substituted hydroxylamines is also covered in this first section by means of phosphorus‐nitrogen or carbon‐nitrogen bond formation reactions. This section also includes several transformations of phosphorus substituted hydroxylamines including among others: rearrangement, hydrolysis, reduction and oxidation reactions. Functionalized oximes containing phosphorus substituents includingO‐ andC‐substituted oximes, and oximes with α‐ and β‐phosphorated moieties are covered in a second section. This provides an introduction to the common approaches to synthesize phosphorus substituted oximes, and the application of phosphorated oximes to the preparation of more elaborated compounds have been described. Some of the synthetic applications methods covered in the second section are fragmentation and rearrangement reactions, nucleophilic substitution at the phosphorus atom, intramolecular reactions, radical reactions, reduction of carbon‐nitrogen double bond, oxidation reactions, olefination reactions, dehydratation of oximes. The third section is dedicated to the synthesis and reactivity of phosphorusO‐,N‐, andC‐substituted hydroxamic acid derivatives, spanning the few reports in the literature covering this topic. An extensive and current list of references and a subject index complete the chapter.

Phosphorus Substituted Hydroxylamine Derivatives

Phosphorus Substituted Oximes

Phosphorus Substituted Hydroxamic Acid Derivatives

Acknowledgments
N‐Arylhydroxylamines and Chemical Carcinogenicity
Authors: Novak Michael , Chakraborty Mrinal
Published: September 2010

Two related classes of carcinogens, arylamines (AAs) and heterocyclic arylamines (HAAs), have played an important role in the development of our understanding of chemical carcinogenesis. AAs are largely industrial products or by‐products, but significant exposure also occurs through inhalation of cigarette smoke. HAAs are produced during broiling or frying of meats and fish and are viewed as significant cancer risks in most human populations. AAs and HAAs are properly characterized as procarcinogens because they require metabolic activation into their ultimate carcinogenic forms. Both classes are activated predominately by cytochrome P450 (CYP450) mediated oxidation intoN‐arylhydroxylamines that are further metabolized into acetic or sulfuric acid esters of the hydroxylamines by the action ofN‐acetyltransferases (NATs) or sulfotransferases (SULTs). These esters appear to be the ultimate carcinogens in most cases. Research on the metabolism of AAs and HAAs, the structures of DNA adducts derived from their carcinogenic metabolites, and the relationship of DNA adduct conformations and persistence to observed mutations are reviewed. Evidence for the proposal that the reactive intermediate responsible for the formation of DNA adducts is a nitrenium ion derived from the hydroxylamine esters is the main topic of this review. Future prospects for research in this area are considered.

Introduction

Metabolic Activation ofAAsandHAAs

The Structures ofDNAAdducts

The Nitrenium Ion Hypothesis

The Hypothesis Tested

Concluding Remarks
Hydroxylamine, Oxime and Hydroxamic Acid Derivatives of Nucleic Acids
Authors: Kojima Naoshi , Komatsu Yasuo
Published: September 2010

Hydroxylamines directly react with nucleobases in genomic DNA, and the damaged nucleobases induce genetic mutations by forming non‐canonical base pairs with natural bases. In contrast, some nucleoside analogues containing hydroxylamine and its related derivatives are known to possess antiviral and anticancer activities by mimicking natural nucleosides. In addition, oligonucleotides with phosphate backbones modified with hydroxylamines show nuclease resistance required for oligonucleotide therapeutics.

This chapter provides the fundamental functions and the applications of hydroxylamine, oxime and hydroxamic acid groups on nucleic acids, consisting of four contents (1. Reactions of hydroxylamine andO‐methylhydroxylamine with nucleobases, 2. Nucleoside and nucleotide analogues consisting of hydroxylamine, oxime and hydroxamic acid groups, 3. A series of oligonucleotides modified at backbone and sugar moieties with these functional groups, and 4. Application for the detection and quantification of DNA lesions by aminooxy probes). Novel nucleic acids will be developed by understanding potential functions of hydroxylamine and its related derivatives.
The Chemistry of Organomanganese Ate Complexes
Authors: Yorimitsu Hideki , Oshima Koichiro
Published: September 2010

The organometallic chemistry of organomanganates is first summarized. X‐ray crystallographic analysis revealed many interesting aspects of organomanganate complexes. Not only sigma‐bonded manganates but also pai‐bonded manganates are intriguing. Second, the application of organomanganates in organic synthesis is described. Organomanganates reacted with carbonyls and organic halides as cuprates do. Halogen‐manganese exchange provides a useful transformation of organic halides, especially of dihalo compounds. Carbometalation via manganates shows unique reactivity. Manganates can serve as reducing agents via single electron transfer.
Bioenergy production chain development in the Netherlands: key factors for success
Authors: Langeveld Johannes (Hans) W.A. , Kalf Ria , Elbersen H. Wolter
Published: September 2010

Development of bioenergy production in the Netherlands is lagging. This paper presents an inventory of problems met by new bioenergy chains and compares these to literature and to other countries. Theoretical frameworks suggest that five elements are crucial for successful bioenergy chain development: (i) availability of (proven) technology; (ii) access to information; (iii) access to feedstocks, financial means, and markets; (iv) locations for new installations; and (v) efficient lobby activities and public support. Nine bioenergy chains were interviewed. Problems that are reported relate to insufficient knowledge of new technological concepts, and of nuisances (noise, emission, odor, and other) caused during bioenergy production. Feedstock markets (wood, byproducts, waste) and product markets (heat, CO2) are underdeveloped, while some chains are experiencing extra problems finding a suitable location or obtaining necessary permits. Problems related to insufficient public support are most relevant for bioenergy chains depending on tax exemptions (pure vegetation oil transportation fuels) or requiring adaptation of legislation (location permits for farm fermenters). An international comparison to barriers for biofuel suggests that economic factors (including lack of capital), limitations in know‐how and institutional capacities, underdeveloped biomass and carbon markets, problems in chain coordination, and limited public support are largest problems for new bioenergy chains. Recommendations to stimulate bioenergy production in the Netherlands refer to performance standards for new installation types, information on feedstock availability, protocols for heat exchange and on improved credit facilities. © 2010 Society of Chemical Industry and John Wiley & Sons, Ltd
Stability‐indicating validation of acitretin and isoacitretin in human plasma by LC‐ESI‐MS/MS bioanalytical method and its application to pharmacokinetic analysis
Authors: Kumar Ajay , Monif Tausif , Khuroo Arshad , Sasmal Dinakar , Goswami Dipanjan , Lahkar Vijay Kumar
Published: September 2010

LC‐ ESI‐ MS/MS simultaneous bioanalytical method was developed to determine acitretin and its metabolite isoacitretin in human plasma using acitretin‐d3 used as the internal standard for both analytes. The compounds were extracted using protein precipitation coupled with liquid–liquid extraction with flash freezing technique. Negative mass transitions (m/z) of acitretin, isoacitretin and acitretin‐d3 were detected in multiple reactions monitoring (MRM) mode at 325.4 → 266.3, 325.2 → 266.1 and 328.3 → 266.3, respectively, with a turbo ion spray interface. The chromatographic separation was achieved on an Ascentis‐RP amide column (4.6 × 150 mm, 5 µm) with mobile phase delivered in isocratic mode. The method was validated over a concentration range of 1.025–753.217 ng/mL for acitretin and 0.394–289.234 ng/mL for isoacitretin with a limit of quantification of 1.025 and 0.394 ng/mL. The intra‐day and inter‐day precisions were below 8.1% for acitretin and below 13.8% for isoacitretin, while accuracy was within ±7.0 and ±10.6% respectively. For the first time, the best possible conditions for plasma stability of acitretin and isoacitretin are presented and discussed with application to clinical samples. Copyright © 2010 John Wiley & Sons, Ltd.
Quantitative determination of cefetamet in human plasma by liquid chromatography–mass spectrometry
Authors: Noh Keumhan , Kim Eunyoung , Kang Wonku
Published: September 2010

Cefetamet is a potent antibiotic to treat respiratory and urinary tract infections. To improve oral bioavailability, it is administered as a prodrug, cefetamet pivoxyl hydrolyzed by esterase following absorption. A quantification method using a mass spectrometry was developed for the determination of cefetamet in human plasma. After a protein precipitation with acetonitrile, the analytes were chromatographed on a reversed‐phase C18 column and detected by a tandem mass spectrometer with electrospray ionization. The accuracy and precision of the assay were in accordance with FDA regulations for the validation of bioanalytical methods. This method was used to measure the concentrations of the cefetamet in plasma after a single oral administration of 500 mg cefetamet pivoxyl. Copyright © 2010 John Wiley & Sons, Ltd.
Sintered Silicon Carbide: A New Ceramic Vessel Material for Microwave Chemistry in Single‐Mode Reactors
Authors: Gutmann Bernhard , Obermayer David , Reichart Benedikt , Prekodravac Bojana , Irfan Muhammad , Kremsner Jennifer M. , Kappe C. Oliver
Published: September 2010

Silicon carbide (SiC) is a strongly microwave absorbing chemically inert ceramic material that can be utilized at extremely high temperatures due to its high melting point and very low thermal expansion coefficient. Microwave irradiation induces a flow of electrons in the semiconducting ceramic that heats the material very efficiently through resistance heating mechanisms. The use of SiC carbide reaction vessels in combination with a single‐mode microwave reactor provides an almost complete shielding of the contents inside from the electromagnetic field. Therefore, such experiments do not involve electromagnetic field effects on the chemistry, since the semiconducting ceramic vial effectively prevents microwave irradiation from penetrating the reaction mixture. The involvement of electromagnetic field effects (specific/nonthermal microwave effects) on 21 selected chemical transformations was evaluated by comparing the results obtained in microwave‐transparent Pyrex vials with experiments performed in SiC vials at the same reaction temperature. For most of the 21 reactions, the outcome in terms of conversion/purity/product yields using the two different vial types was virtually identical, indicating that the electromagnetic field had no direct influence on the reaction pathway. Due to the high chemical resistance of SiC, reactions involving corrosive reagents can be performed without degradation of the vessel material. Examples include high‐temperature fluorine–chlorine exchange reactions using triethylamine trihydrofluoride, and the hydrolysis of nitriles with aqueous potassium hydroxide. The unique combination of high microwave absorptivity, thermal conductivity, and effusivity on the one hand, and excellent temperature, pressure and corrosion resistance on the other hand, makes this material ideal for the fabrication of reaction vessels for use in microwave reactors.
Synthesis and Comparative Characterization of 9‐Boraanthracene, 5‐Boranaphthacene, and 6‐Borapentacene Stabilized by the H2IMes Carbene
Authors: Wood Thomas K. , Piers Warren E. , Keay Brian A. , Parvez Masood
Published: September 2010

A general procedure for the preparation of three N‐heterocyclic carbene stabilized, boron‐containing acenes (9‐boraanthracene, 5‐boranaphthacene, and 6‐borapentacene) is presented. The key steps involve a transmetallation reaction between BCl3 and an appropriate stannacyclic precursor, and the dehydrochlorination of the H2IMes adduct of the chloroborane product. Comparative structural, photophysical, and redox properties reveal narrow HOMO–LUMO gaps relative to the all‐carbon acene analogues.
A theoretical study on the exciton circular dichroism of propeller‐like metal complexes of bipyridine and tripodal tris(2‐pyridylmethyl)amine derivatives
Authors: Fan Jing , Ziegler Tom
Published: September 2010

Time‐dependent density functional theory (TD‐DFT) has been employed to simulate the circular dichroism (CD) spectra of bipyridyl ruthenium(II) complexes as well as zinc(II) and copper(II) complexes containing tris(2‐pyridylmethyl)amine (TPA) derivatives. A qualitative model is used to account for the mechanism by which the bis‐ and tris‐bipyridine complexes (or analogous systems) exhibit exciton CD. The model is further used to predict the sign of the exciton CD bands. The predictions are in agreement with experiment and DFT calculations. A comprehensive analysis is presented of the subtle differences in the CD spectra of this series of related complexes. Chirality, 2011. © 2010 Wiley‐Liss, Inc.
Relief of Angina Pectoris When Carrying Heavy Loads with the Left Hand in a Patient with Previous Coronary Artery Bypass Graft Operation Who Has Severe Exercise Angina: A Case Report
Authors: Tanindi Asli , Cengel Atiye , Akyel Ahmet , Akinci Sinan
Published: September 2010

In patients with known coronary artery disease and/or a history of revascularization, angina pectoris or unstable coronary syndromes are usually attributed to the progression of atherosclerotic lesions rather than an unrecognized great vessel disease. However, for patients with a previous coronary artery bypass graft operation (CABG), during which a left internal mammary artery (LIMA) conduit has been used, great vessel disease, especially subclavian artery stenosis should also be suspected. We present a case of a patient with a LIMA conduit who has angina pectoris on exertion, but interestingly the pain is relieved when he carries heavy loads with his left hand, which can be due to increased blood flow to the LIMA conduit during heavy lifting because of increased peripheral resistance. Copyright © 2010 Wiley Periodicals, Inc.
Synthesis of Benzofuran, Benzothiophene, and Benzothiazole‐Based Thioamides and their Evaluation as KATPChannel Openers
Authors: Fischer Andreas , Schmidt Claas , Lachenicht Stefan , Grittner Dagmar , Winkler Marcus , Wrobel Thomas , Rood Achim , Lemoine Horst , Frank Walter , Braun Manfred
Published: September 2010

Several series of benzofurans, benzothiophenes, and benzothiazoles, all featuring the thioamide group, were synthesized and tested as novel KATPchannel openers in artificial cell systems: CHO cells transfected with SUR1/Kir6.2, and HEK 293 cells transfected with SUR2B/Kir6.1; these served as model systems for insulin‐secreting pancreatic β cells and smooth muscle cells, respectively. All compounds were investigated with respect to their binding affinity for the SUR2B‐type KATPchannels using [3H]P1075 as radioligand. Selected compounds were also tested as agonists in intact cells using DiBAC4(3) and DyeB (R7260) as membrane potential dyes. Remarkable affinity for SUR2B/Kir6.1 channels in the single‐digit micromolar range was observed. In addition, benzothiazole‐derived thioamides with sterically demanding, lipophilic substituents showed >100‐fold selectivity in favor of SUR2B/Kir6.1. A one‐carbon spacer between the heterocyclic skeleton and the thioamide moiety was observed to be crucial for affinity and selectivity. Two of the most potent and selective compounds were studied by crystal structure analyses.
Astroglial structures in the zebrafish brain
Authors: Grupp Larissa , Wolburg Hartwig , Mack Andreas F.
Published: September 2010

Parasagittal cryostat section through the dorsal zebrafish telencephalon stained with antibodies binding to glial fibrillary acidic protein (GFAP; red) and glutamine synthetase (GS; green). Long radial glial fibers were positive for both proteins with GFAP present in the main process and branches (yellow), and GS additionally in finer branches (green areas). Cell nuclei were stained with TOPRO (blue). Note that glial cell bodies are lining the ventricular surface of the everted telencephalon. The Journal of Comparative Neurology, Volume 518, Number 21, 4277–4287.
Non‐recursive functions, knots “with thick ropes,” and self‐clenching “thick” hyperspheres
Authors: Nabutovsky Alexander
Published: September 2010

We introduce an approach to certain geometric variational problems based on the use of the algorithmic unrecognizability of the n‐dimensional sphere for n ≥ 5. Sometimes this approach allows one to prove the existence of infinitely many solutions of a considered variational problem. This recursion‐theoretic approach is applied in this paper to a class of functionals on the space of C1.1‐smooth hypersurfaces diffeomorphic to Sn in Rn+1, where n is any fixed number ≥ 5. The simplest of these functionals kv is defined by the formula kv(Σn) = (vol(Σn))1/n/r(Σn), where r(Σn) denotes the radius of injectivity of the normal exponential map for Σn ⊂ Rn+l. We prove the existence of an infinite set of distinct locally minimal values of kv on the space of C1.1‐smooth topological hyperspheres in Rn+1 for any n ≥ 5.

The functional kv naturally arises when one attempts to generalize knot theory in order to deal with embeddings and isotopies of “thick” circles and, more generally, “thick” spheres into Euclidean spaces. We introduce the notion of knot “with thick rope” types. The theory of knot “with thick rope” types turns out to be quite different from the classical knot theory because of the following result: There exists an infinite set of non‐trivial knot “with thick rope” types in codimension one for every dimension greater than or equal to five.
On the existence of infinitely many periodic solutions to some problems of n‐body type
Authors: Majer Pietro , Terracini Susanna
Published: September 2010

We prove the existence of infinitely many periodic solutions with prescribed period to a class of problems of n‐body type.
The diagnostic value of zinc transporter 8 autoantibody (ZnT8A) for type 1 diabetes in Chinese
Authors: Yang Lin , Luo Shuoming , Huang Gan , Peng Jian , Li Xia , Yan Xiang , Lin Jian , Wenzlau Janet M. , Davidson Howard W. , Hutton John C. , Zhou Zhiguang
Published: September 2010

Background

Zinc transporter‐8 (ZnT8) was recently identified as a novel autoantigen in human type 1 diabetes (T1D). Autoantibody to ZnT8 (ZnT8A) was detected in up to 80% of patients with new‐onset T1D and 26% of patients with T1D otherwise classified as negative on the basis of existing markers. As no data of ZnT8A in Chinese have been reported, we aim to evaluate the utility of ZnT8A for diagnosis of autoimmune T1D in Chinese relative to other autoantibody markers.

Methods

Radioligand binding assays were performed on 539 T1D sera using human ZnT8 carboxyterminal 325Arg construct or a dimer incorporating 325Arg and 325Trp alongside antibodies to glutamic acid decarboxylase (GADA) or insulinoma‐associated protein 2 (IA‐2A). The antigenic specificity was analysed in the context of clinical characteristics of the patients.

Results

ZnT8A were present in 24.1% (130 of 539) of patients with T1D versus 1.8% (10 of 555; P < 0.001) in type 2 diabetes. At diagnosis, ZnT8A and IA‐2A were less prevalent in Chinese subjects with T1D than in Caucasian populations (both P < 0.001) but similar to Japanese. The diagnostic sensitivity of combined GADA, IA‐2A and ZnT8A measurements reached 65.5% with ZnT8A detected in 13.5% (29 of 215) of GADA and/or IA‐2A‐negative subjects. ZnT8A prevalence was lower in older and fatter patients. ZnT8A+ alone patients were distinguished from Ab− ones (P < 0.05–0.001) on the basis of higher insulin requirement and lower systolic blood pressure level.

Conclusion

ZnT8A is an independent marker for T1D in Chinese and combined with GADA and IA‐2A enhances diagnostic sensitivity. ZnT8A may be associated with different clinical phenotypes than GADA or IA‐2A. Copyright © 2010 John Wiley & Sons, Ltd.
A direct role for Wnt8 in ventrolateral mesoderm patterning
Authors: Baker Kevin D. , Ramel Marie‐Christine , Lekven Arne C.
Published: September 2010

Vertebrate dorsoventral patterning requires both Wnt8 and BMP signaling. Because of their multiple interactions, discerning roles attributable specifically to Wnt8 independent of BMP has been a challenge. For example, Wnt8 represses the dorsal organizer that negatively regulates ventral BMP signals, thus Wnt8 loss‐of‐function phenotypes may reflect the combined effects of reduced Wnt8 and BMP signaling. We have taken a loss‐of‐function approach in the zebrafish to generate embryos lacking expression of both Wnt8 and the BMP antagonist Chordin. wnt8;chordin loss‐of‐function embryos show rescued BMP signaling, thereby allowing us to identify Wnt8‐specific requirements. Our analysis shows that Wnt8 is uniquely required to repress prechordal plate specification but not notochord, and that Wnt8 signaling is not essential for specification of tailbud progenitors but is required for normal expansion of posterior mesoderm cell populations. Thus, Wnt8 and BMP signaling have independent roles during vertebrate ventrolateral mesoderm development that can be identified through loss‐of‐function analysis. Developmental Dynamics 239:2828–2836, 2010. © 2010 Wiley‐Liss, Inc.
Synthetic Routes and Plasmonic Properties of Noble Metal Nanoplates Classes of Nanomagnets Created from Alkanethiol‐Coated Pt or Pd Nanoparticles and Their Alloys with Co One‐ and Two‐Dimensional Inorganic Crystals inside Inorganic Nanotubes Covalent Attachment of Aromatic Diisocyanate to the Sidewalls of Single‐ and Double‐Walled Carbon Nanotubes (Eur. J. Inorg. Chem. 27/2010)
Authors: Pastoriza‐Santos Isabel , Miyazaki Akira , Enoki Toshiaki , Tenne Reshef , Kim Yoong Ahm
Published: September 2010

The cover picture a selection of cutting‐edge areas of research on one‐ and two‐dimensional inorganic nanomaterials. I. Pastoriza‐Santos et al. (p. 4288 ff) discuss high‐yield methods of synthesis of both Au and Ag nanoplates and their optical properties, as represented by the EELS intensity distribution map of one silver triangle (middle), related to applications in surface‐enhanced Raman scattering (SERS). The magnetic Pd and Pt nanoparticles covered with alkanethiol groups (top left) are the topic of the Microreview by A. Miyazaki, T. Enoki, et al. (p. 4279 ff), who also report on charge transfer at the metal–organic interface. In their Microreview R. Tenne et al. (p. 4233 ff) demonstrate how the encapsulation of one‐dimensional crystals in inorganic nanotubes lead to filled inorganic nanotube composites (two views of which are in the bottom left and right corners of the cover picture). The double‐walled carbon nanotubes (top right) with optical and chemical activity, which can be applied in preparing multifunctional hybrid materials, are covered in the Short Communication by Y. A. Kim et al. (p. 4305 ff). Thanks are due to all these research groups for contributing their designs to make up this composite cover picture.
Characterization of extra virgin olive oils derived from the Croatian cultivar Oblica
Authors: Zeiner Michaela , Juranovic‐Cindric Iva , Škevin Dubravka
Published: September 2010

The objective of the present research work was the characterization of extra‐virgin olive oils derived from the main cultivar at the Adriatic coast Oblica by the determination of selected organic parameters as well as of the elemental composition. Twenty elements were quantified by inductively coupled plasma – optical emission spectrometry (ICP‐OES) after acidic microwave assisted digestion. In all samples the concentrations of As, Cd, Co, Cr, Mn, Mo, Pb, and V were below the LOD. The mode of production (pressing or centrifugation) is reflected in the contents of Cu, Fe, Ni, and Si. Thus only the contents of Al, Ca, K, Mg, Na, Se, Sn, and Zn ranging from 0.02 – 0.5, 0.8 – 11, 0.1 – 2.5, < LOD – 0.2, 2.7 – 4.2, 0.6 – 2.9, <LOD – 4.8, and 2.5 – 4.0 µg/g oil, respectively, can be used for characterizing the Oblica variety. The organic quality parameters analyzed were free fatty acids (0.1 to 0.6% oleic acid), peroxide value (2.2 to 4.4 mmol O2/kg) and specific absorbances in the UV range (K232 0.8 to 1.9; K270 0.8 to 1.9; 0.08 to 0.21; and ΔK < 0.003).

Practical applications: Oil characterization by organic as well as inorganic parameters is the basis for nutritional and food technological investigations such as adulteration detection and genuineness analysis. Knowing the composition of authentic samples (reference values) is necessary in order to be able to detect differences caused by fraud in products available on the market. Since Croatia is a candidate for entering the European Union the characterization of food stuff coming from this country is of great concern.
Effect of fat composition on texture and bloom of lauric compound chocolate
Authors: Wang Fengyan , Liu Yuanfa , Shan Liang , Jin Qingzhe , Meng Zong , Wang Xingguo
Published: September 2010

Cocoa butter (CB) and milk fat (MF) contents were varied and their effects on the textural property and bloom formation of lauric cocoa butter substitutes (CBS)‐based compound chocolates was investigated. Compositional parameters for CBS compound chocolates were two types of CBS (hydrogenated palm kernel olein (HPKO) and hydrogenated palm kernel sterin (HPKS)), CB (0, 5, 10, and 15%) and MF (0, 3, and 6%) contents. Addition of CB or MF significantly (p<0.001) influenced the hardness of compound chocolates but the effects were less pronounced at higher fat content. Addition of MF or CB accelerated the bloom formation compared with the control samples, but in combination they delayed the bloom formation, suggesting that the mechanisms of bloom formation were different in the CBS compound chocolate made with different fat mixtures.

Practical applications This study deals with the effect of fat composition on both texture and bloom of lauric‐based compound chocolates. CB and MF can be used in lauric‐based compound chocolates to improve the flavor, but eutectic and dilution effects appear when these fats are added separately. However, there are few studies on the interactions of ternary mixtures and the physical properties such as hardness of corresponding compound chocolates. In order to be able to predict the bloom formation, it is important to study how these fats affect the physical properties of the compound chocolates.
Synthesis and DNA Interaction of Platinum Complex/Peptide Chimera as Potential Drug Candidates
Authors: Damian Mariana S. , Hedman Hanna K. , Elmroth Sofi K. C. , Diederichsen Ulf
Published: September 2010

Modification and optimization of the anticancer drug cisplatin is of interest with respect to selective cell targeting and DNA binding efficiency. Attractive approaches contain both, modification of the platinum coordination sphere and design of hybrid molecules of the cisplatin binding moiety including peptide motifs. Peptides with cell penetrating, directing or recognizing properties can be implemented. In this study, positively charged peptide sequences were investigated with the potential of inducing DNA structural distortions caused by charge neutralization of the dsDNA helix. Association of charged peptides is likely to increase the flexibility of the DNA thereby facilitating platinum binding. The synthesis and DNA interaction of five new cisplatin–peptide hybrids with enhanced solubility and potential antitumor activity is presented. Propylenediamine or bisimidazole units were used as bisdentate platinum ligands and were coupled to a peptide sequence in the final elongation step of the solid‐phase peptide synthesis (SPPS). Agarose and polyacrylamide gel electrophoresis, fluorescence intercalation, and thermal UV melting studies, all support the presence of covalently formed platinum DNA adducts in a reaction mediated by the positively charged peptide.
Pd/Cu‐Catalyzed Direct Alkenylation of Azole Heterocycles with Alkenyl Halides
Authors: Sahnoun Sophian , Messaoudi Samir , Brion Jean‐Daniel , Alami Mouâd
Published: September 2010

Direct alkenylation of azole heterocycles through Pd–Cu‐catalyzed C–H bond activation has been reported using alkenyl bromides as the coupling partners. The reaction enables the introduction of various mono‐, di‐, or trisubstituted alkenyl bromides as well as a benzyl chloride to the caffeine core.