bluuebunny/crossref_metadata_2025 huggingface dataset:
Ribonucleases
Authors: Nichols Nicole M. , Yue Dongxian
Published: October 2008

Ribonucleases (RNases) with different sequence or structural specificities are used for a variety of analytical purposes, including RNA sequencing, mapping, and quantitation. The development of RNase protection assays, structural determination assays, and the production of small interfering RNAs (siRNA) employed in RNA interference (RNAi) experiments has depended on the unique substrate specificities of commercially available RNases, including RNases A, I, T1, V1, HI, III, and Dicer. One very common application for high purity RNase A is also presented in this unit and involves hydrolyzing RNA that contaminates DNA preparations. RNase HII and the placental RNase inhibitor are also discussed. Curr. Protoc. Mol. Biol. 84:3.13.1‐3.13.8. © 2008 by John Wiley & Sons, Inc.
Isolation, Culture, and Differentiation Potential of Mouse Marrow Stromal Cells
Authors: Anjos‐Afonso Fernando , Bonnet Dominique
Published: October 2008

This unit describes how to isolate and expand mesenchymal stromal cells (MSCs) from mouse bone marrow. For reasons that are not clear, it has been difficult to isolate these cells (also known as mesenchymal stem cells). Furthermore, different mouse strains seem to have specific requirements for successful extraction and culture of these cells. A general and easy protocol is presented here for isolating stromal cells from different inbred and transgenic mice commonly used in the stem cell biology field. Curr. Protoc. Stem Cell Biol. 7:2B.3.1‐2B.3.11. © 2008 by John Wiley & Sons, Inc.
Memory of children's faces by adults: Appearance does matter
Authors: Gier Vicki Silvers , Kreiner David S.
Published: October 2008

Accurately detecting faces of children when their appearance has been altered is especially important in recognizing abducted or missing child. Face recognition studies have focussed on recognizing the adult perpetrator; however, there is lack of research on recognizing a child's face under different appearances. Two studies were conducted to determine what type of photos may increase recognition of missing children. In Experiment 1 participants were shown pictures of children's faces in a study phase in which their faces were either dirtied with negative affect or clean with positive affect, followed by a recognition phase. Accuracy and confidence were higher when the face at recognition was the same type as in the study phase. Experiment 2 replicated Experiment 1, adding four delay conditions: 10‐minute interval (10‐MI), 3, 6 or 12 week. Accuracy and confidence decreased over time and we again found a significant interaction between face at study and face at recognition. Copyright © 2008 John Wiley & Sons, Ltd.
Impact of sampling method and scale on the measurement of mixing and the coefficient of variance
Authors: Kukuková Alena , Noël Benjamin , Kresta Suzanne M. , Aubin Joelle
Published: October 2008

Spatial statistics methods are used to determine the effect of the sampling scale and method on two measures of mixing: the coefficient of variance CoV and the maximum striation thickness. Three sampling methods: quadrats, probes and transects, were tested. Two CFD data sets were used as test cases: dispersion of floating particles in a turbulent stirred tank and laminar mixing of tracer particles in a micromixer. Over 100 probes are needed to track the evolution of the CoV, and the probe size should match the smallest mixing scale of interest. The final value of the CoV varies by up to a factor of 5 as the probe size increases. The most useful measurement is the one which changes the most in the later stages of mixing: intensity of segregation, or CoV, for the turbulent case; and scale of segregation, or maximum striation thickness on a transect, for the laminar case. © 2008 American Institute of Chemical Engineers AIChE J, 2008
Local forcing of a nonlinear surface reaction: CO oxidation on Pt(100)
Authors: Bilbao Daniel , McMillan Noah , Lauterbach Jochen , Snively Christopher M.
Published: October 2008

A novel spatiotemporal perturbation method for nonlinear surface reactions is reported, thus allowing the creation of new spatially localized structures. Forcing was achieved by dosing reactant gases through a capillary positioned near the catalyst surface, providing control over the local surface coverage and reaction rate. The emergence of localized concentration patterns and oscillations in an otherwise stable system is attributed to a local modification of the catalytic properties of the surface due to external forcing. Based on the spatial orientation, the temporal and thermal stability of the modified surface, as well as the affinity of CO toward the perturbed surface, subsurface O is proposed as a possible source of the observed localized patterning and surface memory effect. © 2008 American Institute of Chemical Engineers AIChE J, 2009
Oxidation Leading to Reduction: Redox‐Induced Electron Transfer (RIET)
Authors: Miller Joel S. , Min Kil Sik
Published: October 2008

Complex electron transfer reactions have been characterized whereby in addition to electron transfer, subsequent electrochemical, chemical and even in some cases biological consequences occur. These include a secondary electron transfer that leads to a major rearrangement of the electronic structure, such that an initial oxidation leads to a reduction (or an initial reduction leads to an oxidation) for these valence ambiguous compounds. Mixed valency and valence‐tautomeric behaviors can additionally result from these complex electron‐transfer‐induced reactions.
The sunk‐time effect: An exploration
Authors: Navarro Anton D. , Fantino Edmund
Published: October 2008

We explored the potential for a sunk‐cost effect in the realm of time. Questionnaire studies (Experiments 1–4) obtained a sunk‐time effect that was robust to manipulations of prospective value, individual versus group consequences, and the effort or enjoyment inherent in the time. Behavioral experiments (Experiments 5–7) also suggested a sunk‐time effect and found support for a personal responsibility by sunk‐cost interaction on choice behavior. We discuss theoretical implications and a potential connection to animal sunk‐cost phenomena. Copyright © 2008 John Wiley & Sons, Ltd.
Modelling the Sulfoxygenation Activity of Vanadate‐Dependent Peroxidases
Authors: Wu Pingsong , Santoni Gabriella , Fröba Michael , Rehder Dieter
Published: October 2008

Vanadate‐dependent peroxidases contain, in their active center, vanadate covalently attached to histidine in an overall trigonal‐bipyramidal array. We describe here the synthesis and characterization of optically active amino alcohols and their vanadium(V) complexes, and we show that the structural models of the active center thus obtained are also functional models for the sulfide‐peroxidase activity of the enzyme in heterogeneous catalysis. The heterogeneous systems were obtained by immobilizing the complexes on silica gel and mesoporous silicas, and by aggregation. The following ligands, ligand precursors, and V compounds have been structurally characterized: (R)‐(2‐phenylethanol)‐(R)‐1‐phenylethylamine (HLA), (R,R)‐bis[2‐phenyl(ethylmethylether)]ammonium chloride ([LD]+Cl−), the carbasilatranes (R,R)‐methoxy{N,N′,N″‐2,2′,3‐[bis(1‐phenylethanolato)propyl]amino}silane ((R,R)‐Si(OMe)LE), (R,R)‐methoxy‐{N,N′,N″‐1,2′,3‐[(1‐phenylethanolato)‐(2‐phenylethanolato)propyl]amino}silane ((R,R)‐Si(OMe)LE′), and [VO(LF)(OSiMe2tBu)], where H2LF=ethylbis(2‐hydroxy‐2‐phenylethyl)amine.
Heme‐Copper Oxidases and Their Electron Donors in Cyanobacterial Respiratory Electron Transport
Authors: Bernroitner Margit , Zamocky Marcel , Pairer Martin , Furtmüller Paul G. , Peschek Günter A. , Obinger Christian
Published: October 2008

Cyanobacteria are the paradigmatic organisms of oxygenic (plant‐type) photosynthesis and aerobic respiration. Since there is still an amazing lack of knowledge on the role and mechanism of their respiratory electron transport, we have critically analyzed all fully or partially sequenced genomes for heme‐copper oxidases and their (putative) electron donors cytochrome c6, plastocyanin, and cytochrome cM. Well‐known structure–function relationships of the two branches of heme‐copper oxidases, namely cytochrome c (aa3‐type) oxidase (COX) and quinol (bo‐type) oxidase (QOX), formed the base for a critical inspection of genes and ORFs found in cyanobacterial genomes. It is demonstrated that at least one operon encoding subunits I–III of COX is found in all cyanobacteria, whereas many non‐N2‐fixing species lack QOX. Sequence analysis suggests that both cyanobacterial terminal oxidases should be capable of both the four‐electron reduction of dioxygen and proton pumping. All diazotrophic organisms have at least one operon that encodes QOX. In addition, the highly refined specialization in heterocyst forming Nostocales is reflected by the presence of two paralogs encoding COX. The majority of cyanobacterial genomes contain one gene or ORF for plastocyanin and cytochrome cM, whereas 1–4 paralogs for cytochrome c6 were found. These findings are discussed with respect to published data about the role of respiration in wild‐type and mutated cyanobacterial strains in normal metabolism, stress adaptation, and nitrogen fixation. A model of the branched electron‐transport pathways downstream of plastoquinol in cyanobacteria is presented.
Metal‐Induced Point Defects in DNA: Model and Mechanisms
Authors: Bregadze Vasil G. , Gelagutashvili Eteri S. , Tsakadze Ketevan J. , Melikishvili Sophia Z.
Published: October 2008

The aim of this work was to study the role of H3O+ and transition‐metal (TM) ions in keto–enol and amino–imino tautomeric transitions in DNA base pairs and depurination. In this regard, we discuss the thermodynamic model of ion–DNA interactions and UV display of double‐proton transfer (DPT) in GC. The probabilities and energies of rare tautomeric forms of GC pairs in DNA induced by H3O+ and TM were determined being in the range from 0.02 (for Mg2+) to 1 (for Cu2+), and from 0 kcal/M (for Cu+) to 2.3 kcal/M (for Mg2+), respectively. It was shown that site of DNA double helix, which corresponds to the only triplet 5′UGG3′ of RNA that codes the most valuable amino acid tryptophan, is a good target for TM ions to attack. It was also shown that the only way to obtain the tryptophan‐coding 5′UGG3′ triplet in RNA via transition‐type G→A point mutation caused by TM ions is their interaction with the site of a DNA double helix, which corresponds to 5′CGG3′ triplet of RNA that codes arginine.
Inhibition Mechanism of TbIII on Horseradish Peroxidase Activity
Authors: Guo Shaofen , Zhou Qing , Lu Tianhong , Ding Xiaolan , Huang Xiaohua
Published: October 2008

The inhibition mechanism of TbIII on horseradish peroxidase (HRP) in vitro was discussed. The results from MALDI‐TOF/MS and X‐ray photoelectron spectroscopy (XPS) showed that TbIII mainly interacts with the O‐containing groups of the amides in the polypeptide chains of the HRP molecules and forms the complex of TbIII–HRP, and, in the complex, the molar ratio TbIII/HRP is 2 : 1. The results from CD and atomic force microscopy (AFM) indicated that the coordination effect between TbIII and HRP can lead to the conformation change in the HRP molecule, in which the contents of α‐helix and β‐sheet conformation in the peptide of the HRP molecules is decreased, and the content of the random coil conformation is increased. Meanwhile, the coordination effect also leads to the decrease in the content of inter‐ and intrapeptide‐chain H‐bonds in the HRP molecules, resulting in the HRP molecular looseness and/or aggregation. Thus, the conformation change in the HRP molecules can significantly decrease the electrochemical reaction of HRP and its electrocatalytic activity for the reduction of H2O2.
Antimicrobial Activity of Ethylenediaminedisuccinate Metal Complexes. Short Communication
Authors: Costa Natália J. S. , Bombardieri Cíntia R. , Kuribayashi Juliana S. , de Camargo Maristela M. , Andrade Leandro H. , Kagohara Edna , Espósito Breno P.
Published: October 2008

It is shown that metal complexes of the biodegradable ligand ethylenediaminedisuccinic acid (edds) present antimicrobial activity towards fungi and bacteria. [Cd(edds)], in particular, is more toxic than free Cd2+ to Aspergillus niger, behaving as a ‘Trojan Horse’ in the facilitated delivery of the toxic metal into the fungus.
Nanotechnologie für das Smart Energy Home
Authors: Iden R. , Wullkopf U. , Wohlleben W. , Keßenich E.
Published: October 2008

Die Verknappung fossiler Ausgangsstoffe sowie Klimaschutz und Importabhängigkeit im Energiesektor sind Herausforderungen, mit denen Europa in den nächsten Jahren konfrontiert sein wird. Europa ist bereits Weltführer bei neuen energieeffizienten Baumaterialien, intelligenten Geräten, alternativen Energiesystemen im Wohnbereich, Isolierung und nachhaltigen Verbraucherprodukten. Verglichen mit anderen Regionen der Welt schneiden die europäischen Gebäude in Bezug auf Energieeffizienz mit am besten ab. Europäische Unternehmen haben außerdem begonnen, neue Technologien in Musterhäuser und Entwicklungen zu integrieren. Diese Stärken und das zur Verfügung stehende Wissen müssen gefördert werden, indem die Marktakzeptanz neuer, energieeffizienter Technologien beschleunigt wird. Eine wachsende Nachfrage wird außerdem zu effizienterer Massenproduktion und somit niedrigeren Preisen für solche Produkte führen.
Significant Influence of Zn on Activation of the C‐H Bonds of Small Alkanes by Brønsted Acid Sites of Zeolite
Authors: Stepanov Alexander G. , Arzumanov Sergei S. , Gabrienko Anton A. , Parmon Valentin N. , Ivanova Irina I. , Freude Dieter
Published: October 2008

Herein, we analyze earlier obtained and new data about peculiarities of the H/D hydrogen exchange of small C1–n‐C4 alkanes on Zn‐modified high‐silica zeolites ZSM‐5 and BEA in comparison with the exchange for corresponding purely acidic forms of these zeolites. This allows us to identify an evident promoting effect of Zn on the activation of CH bonds of alkanes by zeolite Brønsted sites. The effect of Zn is demonstrated by observing the regioselectivity of the H/D exchange for propane and n‐butane as well as by the increase in the rate and a decrease in the apparent activation energy of the exchange for all C1–n‐C4 alkanes upon modification of zeolites with Zn. The influence of Zn on alkane activation has been rationalized by dissociative adsorption of alkanes on Zn oxide species inside zeolite pores, which precedes the interaction of alkane with Brønsted acid sites.
Building theories of economic process
Authors: Shubik Martin , Smith Eric
Published: October 2008

Economics concerns phenomena on the interface between materials and processes in the physical world and strategic actions in cognitive, legal, and cultural realms. A very limited set of questions about the existence of rationally optimal allocations of goods has been asked within the mathematical framework of economic general equilibrium theory. Independently, diverse ad hoc models of particular economic systems have been built in operations research, macroeconomics, and most recently in the growing field of econophysics. Adequate attention has not been given, up to recently, to frameworks for integrative modeling of economic process, comparable in generality to the mathematics of equilibrium theory but capable of reproducing the dynamics and contingency structure of physical and strategic transformations, and the institutions that serve them. We sketch a possible form for such a general modeling framework, with particular attention to the control relation of the financial sector to the underlying productive economy. We emphasize the importance of the structure of physical processes to economic phenomena, particularly symmetries associated with scaling and the continuous or discrete passage of time. Finally, as an example of the kind of problem such a framework seems necessary to understand, we discuss the famous Fisher equation for the velocity of money and its implications for the use of money supply as a control over trade. © 2008 Wiley Periodicals, Inc. Complexity, 2009
Computer‐assisted image analysis of amyloid deposits in abdominal fat pad aspiration biopsies
Authors: Bardarov Svetoslav , Michael Claire W. , Pu Robert T. , Pang Yijun
Published: October 2008

Amyloidosis is a heterogeneous group of diseases with a common outcome: deposition of insoluble protein in the visceral organs and tissues. Primary amyloidosis is a consequence of different plasma cell disorders, and it is the most common form of amyloidosis in the United States with an estimated 2,000 new cases annually. Other forms of amyloidosis include chronic inflammatory processes, familial type of amyloidosis, and localized forms like Alzheimer's disease.

The diagnosis of amyloidosis is based on the clinical picture and demonstration of amyloid deposit in tissues with Congo‐red stain. In our article, we describe a simple methodology for image analysis of fat pad biopsies for amyloidosis using a commercially available software Adobe Photoshop CS3© Extended Edition. The principle is based on calculation of the mean gray value of each blue and green channel and comparison of their ratios. As a negative control, we have used samples from heart, scar tissue, and skin with their representative control. Fibrous tissue often gives a white:blue to blue:green birefringence, which often is confused with the apple: green birefringence of the amyloid stain; however, we were successful in discriminating these colors using the methodology described in this article. We also analyzed 22 patients with at least 2 years follow‐up in our institution. The specificity and the sensitivity of the computer‐assisted image analysis were calculated to be 75% and 100%, respectively. These results are in agreement with the published papers (references here); however, caution should be exercised before drawing firm conclusions because of the small sample size presented here. Diagn. Cytopathol. 2009. © 2008 Wiley‐Liss, Inc.
Fine‐needle aspiration diagnosis of squamous cell carcinoma in a lymph node involved with small lymphocytic lymphoma: Case report and review of the literature
Authors: McElroy Clinton , Velilla Rowena , Chaudhary Humera , Al‐Abbadi Mousa A.
Published: October 2008

Diagnosis of two distinct malignant entities existing concurrently and at the same location (synchronous malignancy) by fine‐ needle aspiration (FNA) is unusual but may occur. Small lymphocytic lymphoma/chronic lymphocytic leukemia (SLL/CLL) in particular is associated with an increased incidence of secondary tumor, likely due to associated immunodeficiency. Co‐occurrence of some carcinomas such as squamous cell carcinoma (SCC), may show especially aggressive behavior. A 57‐year‐old Caucasian male presented with recurrent upper extremity lymphedema and diffuse lymphadenopathy of the axillary and cervical regions. FNA of a large cervical lymph node was diagnostic for both atypical lymphocytic proliferation and SCC. Flow cytometric analysis showed the atypical lymphocytic proliferation to be positive for CD5, CD23, CD19, CD20, HLA‐DR, CD38, and the population was kappa light chain restricted. These cells were negative for CD‐10 and FMC‐7 antigens, suggesting a phenotype of B‐cell SLL/CLL. We report a rare occurrence of metastatic SCC to a lymph node infiltrated by SLL/CLL. The diagnosis was achieved by a combination of cytomorphologic examination of FNA smears, immunohistochemical staining of cell block material, and flow cytometry on the sample obtained by FNA. To the best of our knowledge, only three cases of SCC metastasis to SLL/CLL diagnosed by FNA have been reported in the English literature. Though rare, awareness of such a possibility and careful cytological examination under the appropriate clinical conditions is warranted. Diagn. Cytopathol. 2009. © 2008 Wiley‐Liss, Inc.
High‐grade urothelial carcinoma: Comparison of SurePath liquid‐based processing with cytospin processing
Authors: Lu David Y. , Nassar Aziza , Siddiqui Momin T.
Published: October 2008

There is limited literature available comparing SurePath (SP) with conventional cytospins (CS) for urine cytology specimens, especially urothelial carcinoma. In this study, urinary tract cytology cases of high‐grade urothelial carcinoma were assessed on SP and CS slides. Also, the morphologic differences of high‐grade urothelial carcinoma between SP and CS were evaluated on a total of 35 cases of high‐grade urothelial carcinoma. SP showed that the tumor cells tend to present as three‐dimensional groups and have a smaller cell size than CS. In terms of nuclear features, SP and CS were found to be comparable in morphologic assessment of the tumor cells, with CS providing a slightly better visualization. Diagn. Cytopathol. 2009. © 2008 Wiley‐Liss, Inc.
One‐Electron Oxidation and Sensitivity of Uric Acid in On‐Line Electrochemistry and in Electrospray Ionization Mass Spectrometry
Authors: Mautjana Nare Alpheus , Estes Joshua , Eyler John R. , Brajter‐Toth Anna
Published: October 2008

The sensitivity of detection of uric acid (H2U) in positive ion mode electrospray ionization mass spectrometry (ESI MS) was enhanced by uric acid oxidation during electrospray ionization. With a carrier solution of pH 6.3>pKa1=5.4 of H2U, protonated unoxidized uric acid [H2U+H]+ (m/z 169) was detected together with the protonated uric acid dimer [2H2U+H]+ (m/z 337). The dimer likely forms by 1e− oxidation of urate (HU−) followed by rapid radical dimerization. A covalent structure of the dimer was verified by H/D exchange experiments. Efficiency of 2e−, 2H+ oxidation of uric acid is low during ESI in pH 6.3 carrier solution and improves when a low on‐line electrochemical cell voltage is floated on the high voltage of the ES in on‐line electrochemistry ESI MS (EC/ESI MS). The intensity of the uric acid dimer decreases with an increase in the low applied voltage. In a carrier solution with 0.1 M KOH, pH 12.7>pKa2=9.8 of H2U, allantoin (Allnt) (MW 158.04), the final 2e−, 2H+ oxidation product of uric acid, was detected as a potassium complex [K(Allnt)+K]+ (m/z 235) and the [2H2U+H]+ dimer was not detected. In direct ESI MS analysis of 1000‐fold diluted urine [NaHU+H]+ (pKsp NaHU=4.6) was detected in 40/60 (vol%) water/methanol, 1 mM NH4Ac, pH ca. 6.3 carrier solution. A new configuration of the ESI MS instrument with a cone‐shaped capillary inlet significantly enhanced sensitivity in ESI and EC/ESI MS measurements of uric acid.
An Electrochemical Immunosensor for C‐Reactive Protein Based on Multi‐Walled Carbon Nanotube‐Modified Electrodes
Authors: Buch Michal , Rishpon Judith
Published: October 2008

C‐reactive protein (CRP) is a nonspecific biomarker of inflammation and infection that can be used as a predictive risk marker of cardiovascular disease in asymptomatic individuals or as a prognostic marker of recurrent ischemia and death among patients with coronary heart disease or stroke. We developed a sensitive, disposable, and easy to operate sensor based on heterogeneous sandwich immunoassay for high sensitivity CRP (hs‐CRP) measurement. We used screen‐printed electrodes modified with multi‐walled carbon nanotubes and protein A to ensure the oriented immobilization of anti‐CRP antibodies. CRP was quantitatively measured down to a concentration of 0.5 ng mL−1, enabling high dilution of the samples before measurement and consequently reducing interferences present in the serum. The sensor developed is suitable for point of care detection of hs‐CRP at clinically relevant concentrations for the diagnosis of both conventional and low‐grade inflammations.
Influence of the Chain Length of Alkanethiols in Self‐Assembled Submonolayers on the Electrochemical Response of Aromatic Amine Mixtures
Authors: Carrillo Idania , Quintana Ma Carmen , Esteva Ana Margarita , Hernández Lucas , Hernández Pedro
Published: October 2008

Alkanethiols, such as di‐n‐octadecyldisulfide, octanethiol, and ethanethiol, have been employed for self‐assembled monolayers on a gold electrode to study the influence of their chain length on the electrochemical response of aniline and 4‐aminobiphenyl. The responses of individual solutions and mixtures of both compounds show that the organization of the submonolayer built can improve the selectivity in the electrochemical analysis of those aromatic amines. The use of C8 10−2 M allows the analysis of 4‐aminobiphenyl avoiding the aniline response. A better resolution for the analysis of those amine mixtures was obtained if a C18 10−6 M modified gold electrode was used instead of an unmodified one.
Synthesis of 1,2,3‐Triazole Analogues of Lincomycin
Authors: Collin Marie‐Pierre , Hobbie Sven N. , Böttger Erik C. , Vasella Andrea
Published: October 2008

In search for new antibiotics we replaced the amide moiety of lincomycin 1 by a 1,2,3‐triazole ring. The 1,2,3‐triazoles 10a–10k were obtained as single regioisomers by ‘click reaction’ of azide 5 with the alkyne 9k, derived from propyl hygric acid, and the alkyl, aryl, or cycloalkyl alkynes ribosomes 9a–9j. The new analogues proved inactive towards wild‐type and A2058G mutant.
New Antioxidant Phenolic Glucosides from Viburnum dilatatum
Authors: Wu Bin , Wu Saiwei , Qu Haibin , Cheng Yiyu
Published: October 2008

Chemical investigation of the fruits of Viburnum dilatatum Thunb. resulted in the isolation and characterization of four new phenolic glycosides, jiamiziosides A–D (1–4), together with five known compounds. Their structures were established by spectroscopic means and by comparison with the literature values. The antioxidant activities of the new isolates were determined against 2,2‐diphenyl‐1‐picrylhydrazyl (=2,2‐diphenyl‐1‐(2,4,6‐trinitrophenyl)hydrazinyl; DPPH) and superoxide radicals. Among the compounds tested, jiamizioside C (3) possesses the most potent inhibitory scavenging effect on DPPH and superoxide radicals with IC50 values of 16.8 and 17.8 μM, respectively.
New Acyclic 12‐Hydroxygeranylgeraniol‐Derived Diterpenoids from the Seeds of Carpesium triste
Authors: Gao Xue , Zhang Zhan‐Xin , Jia Zhong‐Jian
Published: October 2008

Five new acyclic 12‐hydroxygeranylgeraniol‐derived diterpenoids, i.e., 1–5, were isolated from the seeds of Carpesium triste. The structures including the absolute configurations of the new compounds were elucidated by spectroscopic methods. All the compounds, except for 2, were evaluated for their in vitro cytotoxic activity against cultured SMMC‐7721 (human hepatoma), HL‐60 (human promyelocytic leukemia), and L02 (human hepatocyte) cells.
Cultivation of flax in spoil‐bank clay: Mycorrhizal inoculation vs. high organic amendments
Authors: Püschel David , Rydlová Jana , Sudová Radka , Gryndler Milan
Published: October 2008

A greenhouse experiment was focused on the application of arbuscular mycorrhizal fungi (AMF) in effective crop production during reclamation of coal‐mine spoil banks. The aim of the study was to find out whether mycorrhizal inoculation improves growth of flax (Linum usitatissimum L.) and whether it can compensate for high doses of expensive organic amendment. Flax was planted in original spoil‐bank gray Miocene clay amended with organic matter used for spoil‐bank reclamation (mixture of composted urban waste and lignocellulose papermill waste). This amendment was applied in four descending doses equivalent to the application of 500, 200, 100, and 0 t ha–1. The plants received either a mixed inoculum of three AMF species (Glomus mosseae, G. claroideum, and G. intraradices) or were left uninoculated. Growth of flax was significantly increased by mycorrhizal inoculation in pure clay (by 60%) as well as in clay with all amendment doses (by 119% on average). Also, the addition of organic matter increased plant growth but, interestingly, the biomass production was comparable regardless the dose of amendment. Our results suggest that similar yields are attainable with only one fifth of the usual fertilization dose, which can significantly decrease costs related to the reclamation of spoil banks. If mycorrhizal inoculation is applied together with the optimized fertilization, growth of flax planted in spoil‐bank clay can be further improved.
Raman spectroscopy at the beginning of the twenty‐first century II
Authors: Deckert V. , George M. W. , Umapathy S.
Published: October 2008

This special issue of Journal of Raman Spectroscopy is published in honour of Professor Hiro‐o Hamaguchi on the occasion of his 60th birthday. The papers have been contributed by his colleagues who have had and continue to have the privilege of working with or alongside him. They highlight some of the areas in which Hiro‐o has made significant contributions to vibrational spectroscopy, including time‐resolved spectroscopy, instrument and technique development, microscopy and the application of Raman spectroscopy to probe biological systems. Copyright © 2008 John Wiley & Sons, Ltd.
Use of graphitic carbon black and primary secondary amine for determination of 17 organophosphorus pesticide residues in spinach
Authors: Li Li , Li Wei , Ge Jing , Wu Yijun , Jiang Shuren , Liu Fengmao
Published: October 2008

Graphitized carbon black (GCB) and primary secondary amine (PSA) as dispersive‐SPE sorbents were applied to optimize the method for the determination of 17 organophosphorus pesticides in spinach which contained so many pigments using GC with flame photometric detector (FPD). The sample was extracted with ACN, and an aliquot of the extract was concentrated to near dryness. Ethyl acetate or acetone was chosen as the dissolving solvent. Subsequently, dispersive‐SPE was used for cleanup, and the type and quantity of sorbents (GCB, PSA and activated carbon) were tested in the experiments. The best results were when acetone was used to dissolve and 30 mg each of GCB and PSA for cleanup. In this condition, recoveries of pesticides analyzed were between 52–117% with RSD below 10%, and LOQ ranged from 10 to 20 μg/kg. This method was simple, effective and efficient, and can protect the GC system to some extent.
Application of Monte Carlo simulation method to polymerization kinetics over Ziegler–Natta catalysts
Authors: Salami‐Kalajahi Mehdi , Najafi Mohammad , Haddadi‐Asl Vahid
Published: October 2008

In the current work, the Monte Carlo simulation method was applied to ethylene polymerization over Ziegler–Natta catalysts. As expected, polymerization over each center of a Ziegler–Natta catalyst leads to a polymer having a Schultz–Flory molecular weight distribution. Notwithstanding, the total molecular weight distribution obtained by all catalyst centers together is at least twice as broad as that of each center. As another interesting finding, the introduction of hydrogen to the reaction deactivates the catalyst active centers and thereby reduces the catalyst activity. Nevertheless, it does not mainly affect the polymerization kinetics. In addition, the polymer molecular weight falls as hydrogen is added to the reaction since it acts as a strong transfer agent. The same effect is seen when cocatalyst concentration increases. Hydrogen also widens the polymer molecular weight distribution. © 2008 Wiley Periodicals, Inc. Int J Chem Kinet 41: 45–56, 2009
Profile nach Maß
Authors: Meyer Gregor , Winkel Gerlinde
Published: October 2008

Im Stahl‐, Fassaden‐, Anlagenbau sowie im maritimen Bereich besteht ein ständig steigender Bedarf an maßgeschneiderten geschweißten Profilen. Das Laserstrahlschweißen ist ein etabliertes Verfahren zur Fertigung von maßgeschneiderten Profilen aus austenitischen CrNi‐Stählen. Für die Fertigung von Standard‐ und Sonderprofilen aus Baustählen größerer Blechdicken wird häufig das Laser‐MSG‐Hybridschweißen angewendet.
Schweiß‐ und Lötnähte automatisch überwacht
Authors: Müller‐Borhanian Jürgen , Halschka Martin
Published: October 2008

Die heutigen Produktionsprozesse erfordern zunehmend eine automatisierte Prozess‐ bzw. Qualitätsüberwachung ‐ mit Sicherheit gehört sie zukünftig zur Standard‐Ausstattung jeder industriellen Laserapplikation. Da die stetige Prozessanalyse Fehlschweißungen vermeidet, sinkt die Ausschussrate und die Qualität der ausgelieferten Produkte erhöht sich messbar. Die Investitionen wirken sich daher mittel‐ und langfristig Kosten senkend aus.
Maximal zulässige Bestrahlung durch Laserlicht
Authors: Foth Hans‐Jochen
Published: October 2008

Dass ein Laser ein gefährliches Gerät ist, wurde sehr kurz nach seiner Entdeckung bereits im Kino demonstriert. Der erste Laser war bekanntlich 1960 der Rubinlaser von Th. Maiman. Es war ein gepulstes System mit sehr niedrigen Emissionswerten. Auch die in den nächsten Jahren entwickelten Systeme waren nicht sehr kraftvoll. Erst 1963 gelang mit dem He‐Ne‐Laser der erste kontinuierliche Laser mit Leistungen nahe einem mW. Dennoch wurde 1963 in dem James Bond Film „Goldfinger”︁ ein leistungsstarkes Gerät eingesetzt, mit dem Goldplatten zu scheiden waren und beinahe auch Körperteile der 007‐Agenten.
Über Kunden, Konkurrenten und Karrieren
Authors: Leibinger Peter
Published: October 2008

Trumpf gehört zu den weltweit größten Anbietern von Werkzeugmaschinen und zählt zu den führenden Firmen in der Fertigungs‐ und Medizintechnik sowie der Elektronik. Im Bereich industrieller Laser und Lasersysteme ist Trumpf Weltmarkt und Technologieführer. Peter Leibinger, stellvertretender Vorsitzender der Geschäftsführung der Trumpf GmbH + Co. KG, spricht im Laser Technik Journal über alte Kunden, neue Technologien, zukünftige Chancen und über fehlende Frauen in Entwicklungsabteilungen.
How to score alternatives when criteria are scored on an ordinal scale
Authors: Grabisch Michel
Published: October 2008

We address in this paper the problem of scoring alternatives when they are evaluated with respect to several criteria on a finite ordinal scale E. We show that in general, the ordinal scale E has to be refined or shrunk in order to be able to represent the preference of the decision maker by an aggregation operator belonging to the family of mean operators. This paper recalls previous theoretical results of the author giving necessary and sufficient conditions for a representation of preferences, and then focuses on describing practical algorithms and examples. Copyright © 2008 John Wiley & Sons, Ltd.
Efficiency in complementary partnerships with competition
Authors: Sand Jan Y.
Published: October 2008

The objective of this paper is to show how efficiency can be implemented in a market with strictly complementary inputs when the productive firms undertake unobservable effort. The observable output is a joint undertaking by a partnership consisting of two types of firms. It is shown that simple linear sharing rules cannot implement socially optimal effort, but a modified linear sharing rule can implement the first‐best outcome provided that commitment to the proposed sharing rule is possible. This is so even when the sharing rule is proposed by one of the active partners. When opening up for the possibility of renegotiating sharing contracts that have undesirable properties for one or more of the firms, it becomes more difficult to implement socially efficient solutions. Implementation of the socially efficient outcome requires that the sharing rule is proposed by an outsider to the partnership. Copyright © 2008 John Wiley & Sons, Ltd.
Modeling task‐based information seeking on the web: Application of information seeking strategy schema
Authors: Kim Jeonghyun
Published: October 2008

The purpose of this study was to understand how task influences information seeking behavior in the digital information environment of the World Wide Web. To present a conceptual model of task‐based information seeking on the Web, an information seeking strategy schema was developed. This schema is based on several behavioral dimensions. The analysis of strategies is based on data collected through an experiment designed to observe users' behaviors. Three tasks were assigned to thirty graduate students. Data were collected by combining search logs and post‐search interviews. The qualitative and quantitative analysis of the data identified fourteen distinct information seeking strategies. The analysis showed significant differences in the frequencies and patterns of information seeking strategies employed between three tasks. The results of the study were discussed to understand task‐based information seeking behavior on the Web.
Mapping the intellectual impact of library and information science research through citations: A tale of two databases – Scopus and Web of Science
Authors: Meho Lokman I. , Sugimoto Cassidy R.
Published: October 2008

This study uses citations to a group of 42 LIS faculty members to examine the differences between Scopus and WoS in mapping the faculties' intellectual impact, focusing on the sources of their citations by universities, journals, and countries. The study also examines the effects of adding Scopus data on results obtained from WoS. Findings show that while Scopus does not significantly influence the rankings of the top citing journals, institutions, or countries, the database is necessary to use in addition to WoS in order to accurately map the intellectual impact of the faculty members examined and identify more correctly the extent of their research influence on the wider scientific community.
The effect of clay dispersion on the properties of LLDPE/LLDPE‐g‐MAH/montmorillonite nanocomposites
Authors: Stoeffler Karen , Lafleur Pierre G. , Denault Johanne
Published: October 2008

In this work, three coupling agents presenting different grafting contents and molecular weights were used to prepare linear low density polyethylene (LLDPE)/linear low density polyethylene grafted with maleic anhydride (LLDPE‐g‐MAH)/montmorillonite nanocomposites with various morphologies. The clay dispersion was analyzed at the micrometric level by scanning electron microscopy and at the nanometric level by X‐ray diffraction (XRD) and transmission electron microscopy (TEM). It was found that coupling agents having intermediate molecular weights led to the highest exfoliation extents, whereas the coupling agent presenting the highest molecular weight led to a poor delamination of the clay platelets. The properties of the nanocomposites produced and of their LLDPE/LLDPE‐g‐MAH reference blends were analyzed. It was shown that the best improvements in mechanical and barrier properties are not necessarily achieved for the nanocomposites, exhibiting the highest exfoliation extents. The length of the tactoids also plays a crucial role on the macroscopic properties. In addition, a high level of delamination could result in a loss of reinforcement effect, due to the inherent flexibility of the individual clay platelets. Finally, the strength of the clay/polymer interface, which was evaluated through surface tension measurements, seems to play a significant role on the properties of the nanocomposites. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers.
Evaluation of the utility of neutral‐loss‐dependent MS3 strategies in large‐scale phosphorylation analysis
Authors: Villén Judit , Beausoleil Sean A. , Gygi Steven P.
Published: October 2008

Phosphopeptide identification and site determination are major challenges in biomedical MS. Both are affected by frequent and often overwhelming losses of phosphoric acid in ion trap CID fragmentation spectra. These losses are thought to translate into reduced intensities of sequence informative ions and a general decline in the quality of MS/MS spectra. To address this issue, several methods have been proposed, which rely on extended fragmentation schemes including collecting MS3 scans from neutral loss‐containing ions and multi‐stage activation to further fragment these same ions. Here, we have evaluated the utility of these methods in the context of a large‐scale phosphopeptide analysis strategy with current instrumentation capable of accurate precursor mass determination. Remarkably, we found that MS3‐based schemes did not increase the overall number of confidently identified peptides and had only limited value in site localization. We conclude that the collection of MS3 or pseudo‐MS3 scans in large‐scale proteomics studies is not worthwhile when high‐mass accuracy instrumentation is used.
Facile preparation of novel epoxy curing agents and their high‐performance thermosets
Authors: Lin Ching Hsuan , Lin Tsung Li , Chang Sheng Lung , Dai Shenghong A. , Cheng Ru Jen , Hwang Kuen Yuan , Tu An Pang , Su Wen Chiung
Published: October 2008

Two flame‐retardant epoxy curing agents, 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐yl‐tris(4‐hydroxyphenyl)methane (1) and 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐yl‐ (4‐aminophenyl)‐bis(4‐hydroxyphenyl)methane (2), were prepared by a facile, economic, one‐pot procedure. The structures of the curing agents were confirmed by IR, high‐resolution mass, 1‐D, and 2‐D NMR spectra. A reaction mechanism was proposed for the preparation, and the effect of electron withdrawing/donating effects on the stabilization of the carbocation was discussed. (1‐2) served as curing agents for diglycidyl ether of bisphenol A (DGEBA), dicyclopentadiene epoxy (HP‐7200), and cresol novolac epoxy (CNE). Properties such as glass transition temperature, coefficient of thermal expansion, thermal decomposition temperature, and flame retardancy of the resulting epoxy thermosets were evaluated. The resulting epoxy thermosets show high Tg, low thermal expansion, moderate thermostability, and excellent flame retardancy. The bulky biphenylene phosphinate pendant makes polymer chains difficult to rotate, explaining the high Tg and low thermal expansion characteristic. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7898–7912, 2008
Poly(ethylene glycol)/poly(ethyl cyanoacrylate) amphiphilic triblock copolymer nanoparticles as delivery vehicles for dexamethasone
Authors: Lin Xiaona , Zhou Ruimei , Qiao Yong , Jin Fengmin , Zhai Yinglei , Xing Jinfeng , Deng Liandong , Dong Anjie
Published: October 2008

Amphiphilic triblock copolymers, poly(ethyl cyanoacrylate)‐b‐poly(ethylene glycol)‐b‐poly(ethyl cyanoacrylate) (PECA‐b‐PEG‐b‐PECA), were synthesized via oxyanion‐initiated polymerization with sodium alcoholate‐terminated PEG as macroinitiator. PECA‐b‐PEG‐b‐PECA were characterized by gel permeation chromatography system, 1H NMR and FTIR. The results indicate that the copolymerization is well controlled with narrow molecular weight distribution. The dexamethasone (DXM)‐loaded PECA‐b‐PEG‐b‐PECA nanoparticles (NPs) were prepared by nanoprecipitation technique and then characterized by Laser Particle Size Analyzer, 1H NMR and transmission electron microscopy. The drug‐loaded PECA‐b‐PEG‐b‐PECA NPs are of spherical shape with average size of less than 100 nm. The drug‐loaded amount (DLA) and encapsulation efficiency of DLNPs were investigated by HPLC. The results show that DXM can be effectively incorporated into PECA‐b‐PEG‐b‐PECA NPs, which provides an optional delivery system for DXM and other hydrophobic drugs. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7809–7815, 2008
Synthesis and characterization of siloxane resins derived from silphenylene‐siloxane copolymers bearing benzocyclobutene pendant groups
Authors: Zuo Xiaobiao , Chen Jiansheng , Zhao Xiaojuan , Yang Shiyong , Fan Lin
Published: October 2008

Two bis(dimethylamimo)silanes with benzocyclobutene (BCB) groups, bis(dimethylamino)methyl(4′‐benzocyclobutenyl)silane (2) and bis(dimethylamino)methyl [2′‐(4′‐benzocyclobutenyl)vinyl]silane (4), were synthesized from different synthetic routes, which were then employed to prepare two novel silphenylene‐siloxane copolymers (SiBu and SiViBu) bearing latent reactive BCB groups by polycondensation procedure with 1,4‐bis(hydroxydimethylsilyl)benzene. At elevated temperatures these copolymers were readily converted to highly crosslinked films and molding disks with network structures by polymer chain crosslinking, which followed the first‐order kinetic reaction model. The final resins of SiBu and SiViBu demonstrated excellent thermal stability with high glass transition temperatures (218 and 256 °C) and high temperatures at 5% weight loss (553 and 526 °C in N2, 530 and 508 °C in air). After aging at 300 °C in air for 100 h, the cured resins showed weight loss lower than 4%. The films of cured SiBu and SiViBu also exhibited relatively low dielectric constants of 2.66 and 2.64, low dissipation factors of 2.23 and 2.12 × 10−3, low water absorptions (≤0.28%), and high transparence in the visible region with cutoff wavelengths of 321 and 314 nm. Moreover, the aged films exhibited good dielectric properties and low water absorptions. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7868–7881, 2008
Relationships between nanostructure and thermomechanical properties in poly(vinyl alcohol)/montmorillonite nanocomposite with an entrapped polyelectrolyte
Authors: Paranhos Caio M. , Dahmouche Karim , Zaioncz Soraia , Soares Bluma G. , Pessan Luiz A.
Published: October 2008

Poly(vinyl alcohol)/montmorillonite (PVA/MOM) hydrogels containing coacervated microparticles of sulfonated polyester (PES) were prepared by direct mixture of the components in water. The system was characterized by using differential scanning calorimetry (DSC), small‐angle X‐ray scattering (SAXS), and dynamical mechanical analysis (DMA). The influence of PES and MOM on the microstructure of the nanocomposite hydrogels was established. The presence of PES causes a significant change on the crystallinity of PVA. Furthermore, the presence of MOM leads to a hierarchical nanostructure that also contributes to change the crystallinity of PVA. The results of structural investigation are correlated with the mechanical properties of the composites obtained by DMA. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 2618–2629, 2008
Cold crystallization and postmelting crystallization of PLA plasticized by compressed carbon dioxide
Authors: Yu Long , Liu Hongsheng , Dean Katherine , Chen Ling
Published: October 2008

The cold crystallization at temperature Tcc (melting > Tcc > glass transition) and the postmelting crystallization of polylactic acid plasticized by compressed carbon dioxide (CO2) were studied using a high‐pressure differential scanning calorimeter. The kinetics of the two kinds of crystallization were evaluated by the Avrami equation as a function of pressure at certain temperatures. The effects of using talc as a nucleation agent on the two types of crystallization under pressure were also investigated. The results show that compressed CO2 increased the mobility of the polymer chains in solid state, resulting in an increased rate of cold crystallization. The decreased rate of postmelting crystallization was mainly in the nucleation‐controlled region, which indicates that the number of nuclei was decreased by the compressed CO2. The growth rate of the two crystallization types followed the Avrami equation, but the kinetics of each depended upon temperature and pressure. The inclusion of talc accelerated postmelting crystallization but had little effect on cold crystallization. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 2630–2636, 2008