bluuebunny/crossref_metadata_2025 huggingface dataset:
A Total Synthesis of Tarchonanthuslactone Exploiting N‐Pyrrole Carbinols as Efficient Stereocontrolling Elements.
Authors: Scott Mark S. , Luckhurst Chris A. , Dixon Darren J.
Published: May 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Two Approaches for Efficient Synthesis of (‐)‐Colletol.
Authors: BouzBouz Samir , Cossy Janine
Published: May 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Total Synthesis of Gambierol: The Generation of the A—C and F—H Subunits by Using a C‐Glycoside Centered Strategy.
Authors: Majumder Utpal , Cox Jason M. , Johnson Henry W. B. , Rainier Jon D.
Published: May 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
MOCVD and ALD of High‐ϰ Dielectric Oxides Using Alkoxide Precursors
Authors: Jones Anthony C. , Aspinall Helen C. , Chalker Paul R. , Potter Richard J. , Manning Troy D. , Loo Yim Fun , O'Kane Ruairi , Gaskell Jeffrey M. , Smith Lesley M.
Published: May 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Growth and Magnetotransport Properties of Thin Co2MnGe Layered Structures
Authors: Ambrose Thomas , Mryasov Oleg
Published: May 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Hybrid Metallocene—Phosphazene Polymers
Authors: Allcock Harry R.
Published: May 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
The Discovery of Metallocene and Metallocene‐Like Addition Polymers
Authors: Pittman, Charles U. Jr.
Published: May 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Hybrid Organic—Inorganic Solids for Heterogeneous Asymmetric Catalysis
Authors: Ngo Helen L. , Lin Wenbin
Published: May 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Structure and Mechanism of DNA Polymerase β
Authors: Beard William A. , Wilson Samuel H.
Published: May 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Toward a Detailed Understanding of Base Excision Repair Enzymes: Transition State and Mechanistic Analyses of N‐Glycoside Hydrolysis and N‐Glycoside Transfer
Authors: Berti Paul J. , McCann Joe A. B.
Published: May 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Fragmentation Pathways of Protonated Peptides
Authors: Paizs Bela , Suhai Sandor
Published: May 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Reinigung von Molkeproteinablagerungen mit pulsierender Strömung
Authors: Bode K. , Hooper R. J. , Paterson W. R. , Wilson D. I. , Augustin W. , Scholl S.
Published: May 2006

Häufige Reinigungsintervalle machen das Milch‐Fouling zu einem Problem der milchverarbeitenden Industrie. Der Einsatz einer pulsierenden Strömung hat ein Potenzial zur Verbesserung des Reinigungsprozesses. Die Reinigungszeit kann auch bei niedrigen Temperaturen um mehr als die Hälfte verkürzt werden. Welligkeit der Pulsation und maximale Strömungsgeschwindigkeit sind die entscheidenden Parameter für die Effektivität des Reinigungsprozesses.
Aufwirbelung von auf Oberflächen abgelagerten Partikelschichten
Authors: Schmidt E. , Nitschke D.
Published: May 2006

Die Resuspension, die Wiederaufwirbelung feiner sedimentierter Partikel von Oberflächen, hat weitreichende Bedeutung in Bereichen der Verfahrenstechnik, des Umweltschutzes und des täglichen Lebens. Besondere Aufmerksamkeit ist der Wiederaufwirbelung von brennbaren Stäuben zu widmen. Hieraus ergibt sich das Gefährdungspotenzial von Staubexplosionen. Die Wiederaufwirbelung von Stäuben ist zum Teil an den diskutierten Feinstaubbelastungen in den Innenstädten beteiligt. Zum einen ergeben sich durch Resuspension gesundheitliche Schädigungen, zum anderen können auch wirtschaftliche Schäden auftreten. Auf Grund von Ablösungen von Partikelschichten, z. B. in zuführenden Rohrleitungen, können technische Systeme mit einer erhöhten Staubkonzentration belastet werden. Dies führt häufig zu einer Verringerung der Lebensdauer des Systems. Mit Hilfe eines besseren Verständnisses der zugrunde liegenden Vorgänge können wirksamere Minderungsmaßnahmen entwickelt werden. Vor diesem Hintergrund liefert der Beitrag eine Übersicht über die in der Literatur dokumentierten Modellansätze zum Verständnis der Wiederaufwirbelung von Partikeln im Größenbereich von etwa 1 bis 50 μm.
Analysis of direct hippocampal cortical field CA1 axonal projections to diencephalon in the rat
Authors: Cenquizca Lee A. , Swanson Larry W.
Published: May 2006

The hippocampal formation is generally considered essential for processing episodic memory. However, the structural organization of hippocampal afferent and efferent axonal connections is still not completely understood, although such information is critical to support functional hypotheses. The full extent of axonal projections from field CA1 to the interbrain (diencephalon) is analyzed here with the Phaseolus vulgaris‐leucoagglutinin (PHAL) method. The ventral pole of field CA1 establishes direct pathways to, and terminal fields within, the anterior hypothalamic nucleus, ventromedial hypothalamic nucleus, lateral hypothalamic and lateral preoptic areas, medial preoptic area, and certain other hypothalamic regions, as well as particular midline thalamic nuclei. These results suggest that hippocampal field CA1 modulates motivated or goal‐directed behaviors, and physiological responses, associated with the targeted hypothalamic neuron populations. J. Comp. Neurol. 497:101–114, 2006. © 2006 Wiley‐Liss, Inc.
Tin(IV) Fluoride Complexes with Tertiary Phosphane Ligands – A Comparison of Hard and Soft Donor Ligands
Authors: Davis Martin F. , Clarke Maria , Levason William , Reid Gillian , Webster Michael
Published: May 2006

The first phosphane complexes of the hard Lewis acid SnF4 have been synthesised including trans‐[SnF4(PR3)2] (R = Me or Cy) and cis‐[SnF4(diphosphane)] [diphosphane = R2P(CH2)2PR2, R = Me, Et, Ph or Cy; o‐C6H4(PR2)2, R = Me or Ph] and characterised by IR and multinuclear NMR (1H, 19F, 31P, 119Sn) spectroscopy. The crystal structures of trans‐[SnF4(PCy3)2] and cis‐[SnF4{Et2P(CH2)2PEt2}] are reported. Tin(IV) fluoride complexes of 2,2′‐bipyridyl, 1,10‐phenanthroline, MeO(CH2)2OMe, Me2N(CH2)2NMe2, pyridine and THF have been characterised by multinuclear NMR spectroscopy, the structures of cis‐[SnF4(L–L)] (L–L = 1,10‐phenanthroline and MeO(CH2)2OMe) determined, and the properties were compared with those of the phosphane complexes. Complexes of o‐C6H4(PMe2)2, Et2P(CH2)2PEt2, and MeC(CH2AsMe2)3 with SnCl4 and SnBr4 are also reported and the structures of cis‐[SnCl4{Et2P(CH2)2PEt2}] and cis‐[SnBr4{κ2‐MeC(CH2AsMe2)3}] described. Attempts to prepare tertiary arsane complexes of SnF4 have been unsuccessful. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Novel Poly(ethylene glycol)s Bearing Tributyltin Carboxylate End Groups as Ionophores in the Development of Chloride Ion‐Selective Electrodes
Authors: Tonelli Domenica , Carpani Irene , Mazzocchetti Laura , Angiolini Luigi , Caretti Daniele , Salatelli Elisabetta , Tarterini Fabrizio
Published: May 2006

The potentiometric response characteristics of electrodes based on PVC membranes containing novel polyethylene glycols (PEGs) with tributyltin carboxylate end groups as ionophores for chloride ions were studied in 0.1 M HEPES solution, at the spontaneous pH. The effects of solvent mediator, amount of cationic additive, amount of ionophore and PEG chain length on the behavior of the sensors were investigated. The membranes with the best composition responded to chloride concentration in a linear range from 10−4 to 10−1 M Cl− with a nearly Nernstian slope and a detection limit of 6.5×10−5 M. The sensor showed a short response time (<25 s) in the whole concentration range and an operational lifetime of about one week for the most performing PVC membranes. In comparison with ISEs based on anion exchangers the interferences from the more lipophilic anions were greatly reduced, as inferable by the selectivity coefficients determined with the matched potential method at chloride concentration of 3.0×10−3 M.
Statistical neuroanatomy of the human inferior frontal gyrus and probabilistic atlas in a standard stereotaxic space
Authors: Hammers Alexander , Chen Chi‐Hua , Lemieux Louis , Allom Richard , Vossos Spyridon , Free Samantha L. , Myers Ralph , Brooks David J. , Duncan John S. , Koepp Matthias J.
Published: May 2006

We manually defined the inferior frontal gyrus (IFG) on high‐resolution MRIs in native space in 30 healthy subjects (15 female, median age 31 years; 15 male, median age 30 years), resulting in 30 individual atlases. Using standard software (SPM99), these were spatially transformed to a widely used stereotaxic space (MNI/ICBM 152) to create probabilistic maps. In native space, the total IFG volume was on average 5%, and the gray matter (GM) portion 12% larger in women (not significant). Expressed as a percentage of ipsilateral frontal lobe volume (i.e., correcting for brain size), the IFG was an average of 20%, and the GM portion of the IFG 27%, larger in women (P < 0.005). Correcting for total lobar volume yielded the same result. No asymmetry was found in IFG volumes. There were significant positional differences between the right and left IFGs, with the right IFG being further lateral in both native and stereotaxic space. Variability was similar on the left and right, but more pronounced anteriorly and superiorly. We show differences in IFG volume, composition, and position between sexes and between hemispheres. Applications include probabilistic determination of location in group studies, automatic labeling of new scans, and detection of anatomical abnormalities in patients. Hum Brain Mapp, 2007. © 2006 Wiley‐Liss, Inc.
Host–bacterial interaction in the development of gastric precancerous lesions in a high risk population for gastric cancer in Venezuela
Authors: Kato Ikuko , van Doorn Leen‐Jan , Canzian Federico , Plummer Martyn , Franceschi Silvia , Vivas Jorge , Lopez Gladys , Lu Yanhui , Gioia‐Patricola Lydie , Severson Richard K. , Schwartz Ann G. , Muñoz Nubia
Published: May 2006

Helicobacter pylori (HP) infection affects over 50% of the world's population. The prevalence is over 90% in populations at high risk for gastric cancer, but clinical outcomes of the infection are highly variable and thus host genetic factors have been suggested to play a role in its outcomes in addition to bacterial factors. In this study, we examined the effects of common functional genetic polymorphisms of several proinflammatory cytokines known to be overexpressed in HP‐infected gastric mucosa on the risk of various stages of gastric premalignant lesions. The odds ratios (ORs) and 95% confidence intervals (CI) for atrophic gastritis, intestinal metaplasia and dysplasia were estimated by multinominal logistic regression analysis among 2,033 Venezuelan subjects. There was a significant effect of IL8 ‐251A allele on the prevalence of dysplasia (p = 0.021). The OR associated with the A‐allele was 1.34 (95% CI: 0.82–2.18) for heterozygotes and 2.00 (95% CI: 1.13–3.56) for homozygotes, compared with the TT genotype. Furthermore, there was a statistically significant interaction between the number of A‐alleles and HP cag A genotype (p = 0.009), suggesting that the A‐allele increased the risk of dysplasia only when cag A was present. The OR for the AA compared with TT genotype was 3.22 (95% CI: 1.60–6.52) in this group. There were no associations with other proinflammatory cytokines studied, i.e., IL1β, IL6, monocyte chemoattractant protein 1 (MCP1) and TNFα, or with other stages of premalignant lesions. The present study provides important evidence suggesting host–bacterial interactions in the development of gastric precancerous lesions. © 2006 Wiley‐Liss, Inc.
Improved recovery of B‐phycoerythrin produced by the red microalga Porphyridium cruentum
Authors: Hernandez‐Mireles Tanhia , Rito‐Palomares Marco
Published: May 2006

A simplified process for the primary recovery and purification of B‐phycoerythrin (BPE) from Porphyridium cruentum exploiting aqueous two‐phase systems (ATPS) and isoelectric precipitation was developed in order to reduce the number of unit operations and benefit from increased purity and yield of the protein product. Evaluation of the partitioning behaviour of BPE in polyethylene glycol (PEG)/sulphate, PEG/dextran and PEG/phosphate ATPS was carried out to determine under what conditions the BPE and contaminants concentrated into opposite phases. An additional stage of isoelectric precipitation at pH 4.0 after cell disruption resulted in an increase in purity of the target protein from the BPE crude extract and enhanced the performance of the subsequent ATPS. PEG1000/phosphate ATPS proved to be suitable after isoelectric precipitation for the recovery of highly purified (defined as absorbance ratio A545 nm/A280 nm > 4.0) BPE with a potential commercial value as high as US$ 50/mg. An ATPS extraction stage comprising 29.5% (w/w) PEG1000, 9.0% (w/w) phosphate, a volume ratio (Vr) equal to 1.0, a system pH of 7.0 and loaded with 40% (w/w) of the BPE extract generated by precipitation allowed BPE recovery with a purity of 4.1±0.2 and an overall product yield of 72% (w/w). The purity of BPE from the crude extract increased 5.9‐fold after isoelectric precipitation and ATPS. The results reported herein demonstrate the benefits of the practical application of isoelectric precipitation together with ATPS for the recovery and purification of BPE produced by P. cruentum as a first step in the development of a commercial purification process. Copyright © 2006 Society of Chemical Industry
Drug Release of pH/Temperature‐Responsive Calcium Alginate/Poly(N‐isopropylacrylamide) Semi‐IPN Beads
Authors: Shi Jun , Alves Natália M. , Mano João F.
Published: May 2006

Summary: A series of semi‐interpenetrating, polymer network (semi‐IPN), hydrogel beads, composed of calcium alginate (Ca‐alginate) and poly(N‐isopropylacrylamide) (PNIPAAM), were prepared for a pH/temperature‐sensitive drug delivery study. The equilibrium swelling showed the independent pH‐ and thermo‐ responsive nature of the developed materials. At pH = 2.1, the release amount of indomethacin incorporated into these beads was about 10% within 400 min, while this value approached to 95% at pH = 7.4. The release rate of the drug was higher at 37 °C than that at 25 °C and increased slightly with increasing PNIPAAM content. These results suggest that the Ca‐alginate/PNIPAAM beads have the potential to be used as an effective pH/temperature sustainable delivery system of bioactive agents.

A summary of the temperature‐ and pH‐dependence on the release of the drug over a period of 450 min. The effect of the temperature on the swelling of the beads is shown in the inset.

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A summary of the temperature‐ and pH‐dependence on the release of the drug over a period of 450 min. The effect of the temperature on the swelling of the beads is shown in the inset.
Numerical Simulation of Mesoscopic Mechanical Behaviors of Gradual Multi‐Fiber‐Reinforced Polymer Matrix Composites
Authors: Li Hongzhou , Jia Yuxi , Mamtimin Geni , Wang Xin , Jiang Wei , An Lijia
Published: May 2006

Summary: To simulate the deformation and the fracture of gradual multi‐fiber‐reinforced polymer matrix composites, a numerical simulation method for the mesoscopic mechanical behaviors was developed on the basis of the finite element and the Monte Carlo methods. The results indicate that the strength of a composite increases if the variability of statistical fiber strengths is decreased.

Normalized strength distributions plotted in the Weibull form of $\ln (\sigma /\sigma _{\rm c} )$ versus $\ln [ - \ln (1 - P)]$ for composites with varying WM.

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Normalized strength distributions plotted in the Weibull form of $\ln (\sigma /\sigma _{\rm c} )$ versus $\ln [ - \ln (1 - P)]$ for composites with varying WM.
A First Principle Characterization of Polyethylene, Poly(propylene) and Polystyrene Macroradicals Properties
Authors: Cysewski Piotr , Shyichuk Alexander
Published: May 2006

Summary: Structures of polyethylene, poly(propylene) and polystyrene macroradicals have been studied by means of the B3LYP/6‐31G** method. The polystyrene tertiary alkyl radical has been found to be less active as having spin density partially delocalized on the aromatic ring neighboring to the radical site. Considering the main chain bond orders, the following radicals have been found to be susceptible to main chain scission: the sec‐ and tert‐oxyl poly(propylene) ones, the sec‐ and tert‐oxyl polystyrene ones as well as the tertiary alkyl polystyrene one. The energy levels of the last frontier molecular orbitals in the polyolefin macroradicals have been found to be split up and moved—up and down for HOMOs and LUMOs, respectively. The alkyl macroradicals have single occupied molecular orbital with increased energy. In the oxyl and peroxyl radicals the spin density comes from two or three last orbitals that are spread over a broad molecular region and no single occupied molecular orbital (SOMO) may be identified.

Localization of the spin density.

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Localization of the spin density.
Strain‐specific induction of murine lung tumors following in utero exposure to 3‐methylcholanthrene
Authors: Jennings‐Gee Jamie E. , Moore Joseph E. , Xu Mian , Dance Stephanie T. , Kock Nancy D. , McCoy Thomas P. , Carr J. Jeffrey , Miller Mark Steven
Published: May 2006

Fetal mice are more sensitive to chemical carcinogens than are adults. We previously demonstrated that resistant offspring of a DBA/2 × (C57BL/6 × DBA2) backcross exhibited a high incidence of lung tumors 12–13 mo after transplacental exposure to 3‐methylcholanthrene (MC). We compared the effects of in utero treatment with MC on lung tumor incidence in the offspring of intermediately susceptible BALB/c (C), resistant C57BL/6 (B6), and reciprocal crosses between these strains. Pregnant mice were treated with 45 mg/kg of MC on day 17 of gestation and tumor incidence, multiplicity, and the Ki‐ras mutational spectrum determined in the offspring 12–18 mo after birth. Tumor incidences in C mice and reciprocal crosses were 86% and 100%, respectively, while B6 mice demonstrated resistance to tumorigenesis, with a tumor incidence of 11%. Tumor multiplicities in C, B6C, CB6, and B6 mice were 3.3 ± 3.2, 5.8 ± 3.2, 5.0 ± 2.7, and <0.1, respectively. Ki‐ras mutations, which occurred chiefly in the Ks allele (96%), were found in 79–81% of reciprocally crossed F1 mice, 64% of C mice, and 50% of B6 mice, with the Val12, Asp12, and Arg13 mutations associated with more aggressive tumors. A subset of these mice was used to demonstrate the utility of computer tomography (CT) for the visualization and measurement of lung tumors in the submillimeter range in vivo. Based on known genetic differences in murine strains for lung cancer, our results suggest the presence of a previously unidentified genetic factor(s) which appears to specifically influence lung tumorigenesis following exposure to carcinogens during fetal development. © 2006 Wiley‐Liss, Inc.
Acute motor and sensory axonal neuropathy in Burkitt‐like lymphoma
Authors: Wanschitz Julia , Dichtl Wolfgang , Budka Herbert , Löscher Wolfgang N. , Boesch Sylvia
Published: May 2006

Immune‐mediated neuropathies associated with non‐Hodgkin's lymphoma are rare and can be difficult to delineate from neuropathies of other etiologies. We report the clinical and pathological findings of a 36‐year‐old patient with fulminant quadriplegic neuropathy, left facial nerve palsy, and Burkitt‐like lymphoma. Features of the neuropathy, which occurred during induction chemotherapy with a total cumulative dose of 4 mg vincristine, suggested axonal Guillain–Barré syndrome. There was no evidence of direct malignant infiltration of the peripheral nervous system. We hypothesize that immune mechanisms triggered by the lymphoma initiated damage to the peripheral nervous system and enhanced its vulnerability to the toxic effects of vincristine. Muscle Nerve, 2006
Synthesis and optical and electrochemical properties of copolymers containing 9,9‐dihexylfluorene and 9‐dimethylaminopropylcarbazole chromophores
Authors: Liu Chien‐Hsin , Chen Shinn‐Horng , Chen Yun
Published: May 2006

Soluble and well‐defined 9,9‐dihexylfluorene and 9‐dimethylaminopropylcarbazole based copolymers PFCN and 5PFCN have been prepared by Suzuki coupling polymerization. For comparison, alternate copolymer of 9,9‐dihexylfluorene and 9‐hexylcarbazole (PFC) was also prepared with the same method. Furthermore, alternate copolymer of 9,9‐dihexylfluorene and 9‐dimethylethylammoniumpropylcarbazole (PFCNE) was prepared from PFCN by the ethylation of its dimethylaminopropyl groups with bromoethane. These copolymers were soluble in organic solvents and showed high glass‐transition temperatures (75–160 °C). The optimized architecture of PFCN from a simulation was a spiral, which was different from the linear structure of poly(9,9‐dihexylfluorene) (PFO). Thermogravimetric analysis showed that the residual weights of 5PFCN, PFCN, PFC, and PFCNE at 800 °C were all greater then 50%, whereas PFO showed complete thermal decomposition. Both the absorption and photoluminescence emission peaks of these copolymers showed blueshifts after the introduction of the carbazole units because of reduced conjugation. Moreover, the introduction of 9‐hexylcarbazole and 9‐dimethylamionpropylcarbazole moieties into copolymers PFC and PFCN, respectively, effectively prevented the excimer formation of PFO. According to cyclic voltammetry results, PFCNE containing quaternary amino pendant groups exhibited the most stable reduction–oxidation cycles. The turn‐on electric fields of their electroluminescence devices decreased with increasing carbazole content because of the more balanced carrier injection. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3882–3895, 2006
Swelling behavior of poly{N‐[3‐(dimethylaminopropyl)] methacrylamide‐co‐acrylamide} hydrogels in aqueous solutions of surfactants
Authors: Çaykara Tuncer , Demiray Melike , Güven Olgun
Published: May 2006

Temperature sensitive poly{N‐[3‐(dimethylaminopropyl)]methacrylamide‐co‐acrylamide} [P(DMAPMA‐co‐AAm)] hydrogels were prepared by the free‐radical crosslinking copolymerization of corresponding monomers in water with N,N‐methylenebisacrylamide as the crosslinker, ammonium persulfate as the initiator, and N,N,N′,N′‐tetramethylethylenediamine as the activator. The swelling equilibrium of the P(DMAPMA‐co‐AAm) hydrogels was investigated as a function of temperature in aqueous solutions of the anionic surfactant sodium dodecyl sulfate and the cationic surfactant dodecyltrimethylammonium bromide. In pure water, regardless of the amount of N,N‐methylenebisacrylamide, the P(DMAPMA‐co‐AAm) hydrogels showed a discontinuous phase transition between 30 and 36 °C. However, the transition temperature changed from discontinuous to continuous with the addition of surfactants; this was ascribed to the conversion of nonionic P(DMAPMA‐co‐AAm) hydrogels into polyelectrolyte hydrogels due to the binding of surfactants through hydrophobic interactions. Additionally, the concentrations of free sodium dodecyl sulfate and dodecyltrimethylammonium bromide ions were measured at different temperatures by conductometry, and it was found that the electric conductivity of the P(DMAPMA‐co‐AAm)–surfactant systems depended strongly on the swelling ratio; most notably, it changed drastically near the phase‐transition temperature of the P(DMAPMA‐co‐AAm) hydrogel. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 1645–1652, 2006
Soil dissipation and biological activity of metolachlor and S‐metolachlor in five soils
Authors: Shaner Dale L , Brunk Galen , Belles David , Westra Phil , Nissen Scott
Published: May 2006

The resolved isomer of metolachlor, S‐metolachlor, was registered in 1997. New formulations based primarily on the S‐metolachlor isomer are more active on a gram for gram metolachlor basis than formulations based on a racemic mixture of metolachlor containing a 50:50 ratio of the R and S isomers. The labelled use rates of S‐metolachlor‐based products were reduced by 35% to give equivalent weed control to metolachlor. However, several companies have recently registered new metolachlor formulations with the same recommended use rates for weed control as S‐metolachlor. This research was done to compare the soil behaviour and the biological activity of metolachlor and S‐metolachlor in different soils under greenhouse and field conditions. Although Kd ranged from 1.6 to 6.9 across the five soils, there were no differences in the binding of metolachlor and S‐metolachlor to soil or in the rate of soil solution dissipation in a given soil. However, both greenhouse and field studies showed that S‐metolachlor was 1.4–3‐fold more active than metolachlor against Echinochloa crus‐galli (L.) Beauv. in five different soils and that S‐metolachlor was more active than metolachlor in three Colorado field locations. When the rates of metolachlor and S‐metolachlor were adjusted for S isomer concentrations in the formulations, there were no differences between the formulations in field, greenhouse or bioassay studies. Thus herbicidal activity is due to the S isomers, with the R isomers being largely inactive. Copyright © 2006 Society of Chemical Industry
Interface disorder and layer transitions in Ising thin films
Authors: Bahmad L. , Benyoussef A.
Published: May 2006

The disorder and layer transitions in the interface between an Ising spin‐1/2 film denoted (n ), and an Ising spin‐1 film denoted (m ), are studied using Monte Carlo simulations. The effects of both an external magnetic field, acting only on the spin‐1/2 film, and a crystal magnetic field acting only on the spin‐1 film, are studied for a fixed temperature and selected values of the coupling constant J p between the two films. It is found that for large values of the constant J p, the layers of the film (n ), as well as those of the film (m ), undergo a first order layering transition. On the other hand, the only disordered layer of the film (n ) is that one belonging to the interface films (n )/(m ), for any values of the crystal field Δ . We show the existence of a critical value of the crystal field Δ c, above which this particular layer of the film (n ) is disordered. We found that Δ c depends on the values of the constant coupling J p between the two films. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effects of substitution of Sb for Pd in MnPd3 compound
Authors: Coldea M. , Pop V. , Neumann M. , Isnard O. , Pacurariu R. , Takács A. F. , Pascut L. G.
Published: May 2006

X‐ray photoelectron spectroscopy, magnetization and magnetic susceptibility of MnPd3–x Sbx are reported. The substitution of Pd by Sb leads to drastic changes both in the crystallographic and electronic structure, with remarkable modifications in the magnetic properties of the investigated samples. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Magnetic and magnetotransport properties in (LaxSm1–x)2/3Sr1/3MnO3 (x = 1/3, 1/2 and 2/3) manganites
Authors: Asthana Saket , Nigam A. K. , Bahadur D.
Published: May 2006

The magnetic and transport properties of (Lax Sm1–x )2/3Sr1/3MnO3 (x = 1/3, 1/2 and 2/3) manganites, prepared by the citrate‐gel route, have been investigated. These compounds are found to crystallize in the orthorhombic structure. The hopping between Mn3+ and Mn4+ sites is controlled by the Mn–O–Mn bond angle. The magnetoresistance in 8.5 kOe fields varies from 15 to 25 percent over the temperature range 300 K to 80 K. The conduction mechanism can be understood by using the correlated small polaron model. The metal–insulator as well as magnetic transition temperatures are close to each other, which indicates the dominance of long‐range ferromagnetic ordering in the present system. At low temperatures, a weak ferromagnetic to antiferromagnetic transition is indicated, which could be due to competing superexchange and double exchange interactions. The charge localization at lower temperatures could be the possible explanation for increasing magnetoresistance. The maximum magnetic moment at 5 K, for all the samples is ∼3.6μ B/Mn, which is close to the 3.7μ B/Mn, as obtained by considering the Mn spins only. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Comparative study of optical spectra and electronic structures of CaMoO4 and CaWO4 crystals
Authors: Fujita M. , Itoh M. , Takagi S. , Shimizu T. , Fujita N.
Published: May 2006

Polarized reflectivity spectra of CaMoO4 and CaWO4 single crystals have been measured up to 30 eV by using synchrotron radiation as a light source. The optical constants for a ‐ and c ‐axes are derived from the reflectivity spectra by a Kramers–Kronig analysis. A clear correspondence is found in the main structures of the optical spectra between molybdate and tungstate. It is revealed that the lowest bands peaking at 5.0 eV in CaMoO4 and at 6.0 eV in CaWO4 consisit of some fine structures with distinct dichroism. They are attributed to the joint density‐of‐states; in other words, no structures indicative of exciton transition are found at the fundamental absorption edge. From the comparison of the spectral profiles in CaMoO4 and CaWO4, the structures below 10 eV are ascribed to the transitions from the O 2p valence band to the conduction band mainly made of Mo 4d (W 5d) states, while those above 10 eV are assigned to the transitions to the Ca conduction band. The polarization dependence of the structures below 10 eV is explained well in terms of the intramolecular transition in an oxyanion complex in the scheelite crystal. The energy band structure of CaWO4 is discussed taking into account of the previous results such as the thermostimulated luminescence and the two‐photon excitation. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Blimp‐1 is expressed in human and mouse T cell subsets and leads to loss of IL‐2 production and to defective proliferation
Authors: Santner‐Nanan Brigitte , Berberich‐Siebelt Friederike , Xiao Zheng , Poser Niklas , Sennefelder Helga , Rauthe Stephan , Vallabhapurapu Duttu S. , Berberich Ingolf , Schimpl Anneliese , Kreth Hans‐Wolfgang , Nanan Ralph
Published: May 2006

The transcriptional repressor Blimp‐1 regulates terminal differentiation of B‐lymphocytes and myeloid cells. We now show that Blimp‐1 is also expressed in human and murine primary T lymphocytes. Blimp‐1 expression is highest in freshly isolated primary T cells with an antigen experienced phenotype. Th2 and CD4+CD25+ cells exhibited higher levels of Blimp‐1 mRNA than Th1 cells. However, ectopic expression of Blimp‐1 by retroviral transduction neither altered the frequency of IFN‐γ or IL‐4 producing cells nor did it induce suppressor activity. In non‐polarized cells, retroviral transduction of Blimp‐1 led to a marked reduction in IL‐2 secretion, to an inability to proliferate and to reduced viability. Our data suggest that Blimp‐1 is physiologically expressed in T lymphocytes during late stages of differentiation, induces down regulation of IL‐2 production and a shortened life span and might thus contribute to a limitation of T cell immune responses.
Characterizing the spatial structures of riparian plant communities in the lower reaches of the Heihe River in China using geostatistical techniques
Authors: He Zhibin , Zhao Wenzhi
Published: May 2006

Geostatistical techniques are used to evaluate spatial characteristics of riparian plant communities that were mapped within a portion of the lower reaches of the Heihe River. The spatial structures of different plant communities were characterized using nugget, range and sill parameters of spherical or exponential model variograms. Model variograms revealed different plant communities with distinctive spatial properties that were quantified effectively by the parameters used in these models. Model variograms were fit to experimental variograms calculated from diameter at breast height and plant cover data collected for three 2,000 m × 5 m, nine 500 m × 5 m, and three 200 m × 2 m transects. The 2,000 m × 5 m transects were oriented perpendicular to the river and the other transects were located in such a way as to sample communities dominated by different plants. Riparian plant communities in the lower reaches of the Heihe River show patterns of patchiness, and the plant communities are mainly dominated by mature Populus euphratica, young P. euphratica, Tamarix chinensis, and Sophora alopecuroides. The maximum model variogram range for all communities was 55 m, suggesting that transects must be at least this long in order to be able to classify them unambiguously into recognizable communities. Experimental variograms were calculated for all plants in each of four mapped plant communities. The results show that the T. chinensis and S. alopecuroides dominated plant communities have distinctively large ranges, and the spatial structures of P. euphratica dominated plant communities show multiscale change. In the 2,000 m × 5 m transects, the spatial structures of riparian plant communities show a distinct change at the scale of 430 m, because this scale also is the scale of vegetation patchiness turnover, and at scales of more than 430 m the spatial structure of the community increases significantly. These findings confirm the potential of using high‐resolution remote sensing data and geostatistics for determining the vegetation community structures of riparian plant communities.
Hong Kong English, China English and World English
Authors: Poon Franky Kai-Cheung
Published: May 2006

Some reflections of a practising non-native speaking English teacher. Ten years ago, in a job interview for a teaching post in a government school, The writer was asked: ‘Do you think the government should recruit more native English-speaking teachers so as to boost the English standard of Hong Kong students?’ My answer took the interviewers by surprise: ‘No, I think the money should be spent on training local teachers who are more able to understand the needs of students learning English as a second or foreign language. I believe good English doesn’t necessarily mean British or American English. If we see English as an international language, anyone capable of using it as an effective communication tool can potentially be a good English teacher.’ I got the job, but there are still a few questions in my mind.
Call me madam, or The lost key word
Authors: Hinton Suzanne
Published: May 2006

A short guide to formal address in English
Untersuchung der Wirksamkeit von musikalischer Stimulation bei Herzkatheteruntersuchungen
Authors: Argstatter Heike , Haberbosch Werner , Bolay Hans Volker
Published: May 2006

Zusammenfassung. Hintergrund: Herzkatheteruntersuchungen sind mittlerweile Routineverfahren. Da viele Patienten die Untersuchung als belastend empfinden, wurden begleitende psychosoziale Interventionen vorgeschlagen. Ziel der vorliegenden Studie war die Überprüfung der Wirksamkeit von Musiktherapie bei Herzkatheteruntersuchungen auf das subjektive und objektive Angsterleben sowie eine daraus folgende Reduktion von Sedativa. Methoden: Eine dreiarmige (Musikexposition während der HKU; Musikexposition + ergänzendes musiktherapeutisches Coaching; Kontrollgruppe mit Standardbehandlung) randomisierte Studie mit N = 83 Patienten (48 männlich, 35 weiblich, Alter 66 ± 11 Jahre). Zielvariablen waren subjektiv empfundene Angst (STAI-S) sowie physiologische Variablen (Blutdruck, Puls, Cortisol, IgA). Ergebnisse: In der Expositionsgruppe konnte die subjektive Angst (STAI-S) gegenüber den beiden anderen Gruppen prä-post signifikant gesenkt werden (Exposition 11 P, Coaching 4 P, Kontrolle 6 P; p = .033). Die physiologischen Werte unterschieden sich jedoch nicht, ebenso wenig die Medikation. Diskussion: Durch musikalische Stimulation kann das subjektive Angsterleben beeinflusst werden. Auf physiologische Parameter nimmt die Musikintervention nicht so gezielt Einfluss. In der klinischen Anwendung lässt sich der Einsatz adjuvanter Musiktherapie in Form der Exposition rechtfertigen und empfehlen.
Prävention von Problemen des Sozialverhaltens im Vorschulalter
Authors: Lösel Friedrich , Beelmann Andreas , Stemmler Mark , Jaursch Stefanie
Published: May 2006

Zusammenfassung. Theoretischer Hintergrund: In Deutschland herrscht ein Mangel an methodisch kontrollierten Evaluationen von Programmen zur Prävention von Verhaltensproblemen bei Kindern und Jugendlichen. Fragestellung: Die vorliegende Studie evaluiert die Wirksamkeit eines Kindertrainings, eines Elterntrainings sowie einer Kombination aus beiden Programmen. Methode: Aus einer Stichprobe von 675 Kindergartenkindern und ihren Familien nahmen 227 an einer der drei Trainingsbedingungen teil, 227 Kinder dienten als äquivalente Kontrollgruppe. Erfolgsmaße wurden 2-3 Monate sowie bis zu 24 Monate nach Abschluss der Trainings erhoben. Sie bestanden aus den Angaben von Erzieherinnen im Preschool Social Behavior Questionnaire sowie aus Inhaltsanalysen von Schulzeugnissen der 1. Klasse. Ergebnisse: Die Trainings führten zu kurzzeitigen positiven Effekten bei Problemen des Sozialverhaltens, der Hyperaktivität/Unaufmerksamkeit und emotionalen Störungen. Die deutlichsten Effekte zeigten sich bei den kombinierten Programmen und bei Kindern mit ausgeprägteren Problemen des Sozialverhaltens. Die Langzeiteffekte in den verschiedenen Trainingsbedingungen waren weniger konsistent. Es zeigte sich aber eine generelle Reduktion multipler Verhaltensprobleme in der Schule. Schlussfolgerung: Die Ergebnisse stimmen mit internationalen Meta-Analysen überein und rechtfertigen einen vorsichtigen Optimismus hinsichtlich derartiger Präventionsprogramme.
Wirksamkeit von Präventionsmaßnahmen bei Kindern und Jugendlichen:
Authors: Beelmann Andreas
Published: May 2006

Zusammenfassung. Theoretischer Hintergrund: In den letzten Jahren finden wir international eine sehr umfangreiche Präventionsforschung. Fragestellung und Methode: Die vorliegende Arbeit fasst die Ergebnisse von 23 quantitativen Überblicksarbeiten und Meta-Analysen zu dieser Thematik zusammen. Ergebnisse: Die meisten Arbeiten lagen zur Prävention externalisierender Störungen, zur Suchtprävention und zur Wirksamkeit von Programmen zur allgemeinen Entwicklungsförderung vor. Als generelle Wirksamkeitsschätzung kann von durchschnittlichen Effekten von einer drittel bis einer halben Standardabweichung ausgegangen werden. Gezielte Präventionsmaßnahmen wiesen in der Regel höhere Effektstärken auf als universelle Strategien. Ebenso ergaben Pilotprojekte und Eigen-Evaluationen eine höhere Wirksamkeit der Programme. Schlussfolgerungen: Präventive Maßnahmen haben signifikante und zum Teil beträchtliche Wirkungen auf die Entwicklung von Kindern und Jugendlichen. Weitere Untersuchungen zu den längerfristigen Effekten, zu Fragen der Programm-Implementation, zu Kosten-Nutzen-Aspekten und vergleichenden Analysen von Präventionsalternativen sowie zur Integration erfolgreicher Präventionsprogramme in die Versorgungspraxis sind jedoch dringend erforderlich.
Conversion pathways between a fullerene and a ring among C20 clusters by a sphere contracting walk method: Remarkable difference in local potential energy landscapes around the fullerene and the ring
Authors: Maeda Satoshi , Ohno Koichi
Published: May 2006

Conversion pathways from a fullerene to a ring and vice versa among C20 clusters have been explored. A new technique has been developed for discovering multistep reaction pathways, which can be searched by finding constrained energy minima on spheres whose surfaces are contracting from the starting point to the terminal. Local landscapes that appeared on the pathways were found to be considerably different around the fullerene and the ring, from which one can make a new interpretation for no generation of the C20 fullerene in laser vaporization of graphite.
Spacers’ role in the dynamics of hyperbranched polymers
Authors: Satmarel C. , von Ferber C. , Blumen A.
Published: May 2006

We investigate hyperbranched polymers (HBPs) and highlight the relation between their architecture and their viscoelastic behavior, while paying special attention to the role of the chainlike spacer segments between branching points. For this we study the dynamics of HBP in solution, based on the generalized Gaussian structure formalism, an extension of the Rouse model, which disregards hydrodynamical and excluded volume effects. For HBP the dynamical effects display, beside the obvious contributions of localized modes on the spacers, also remarkable features, as we highlight based on the exact renormalization procedure recently developed by us in J. Chem. Phys. 123, 034907 (2005). We exemplify these features by analyzing the dynamics of randomly linked star polymers and study the impact both of the length and of the spacers’ mobility on the normal modes’ spectra. We compute these modes both by numerical diagonalization and also by employing our renormalization procedure; the excellent agreement between these methods allows us to extend the range of investigations to very large HBP.
Inertial range scaling, Kármán-Howarth theorem, and intermittency for forced and decaying Lagrangian averaged magnetohydrodynamic equations in two dimensions
Authors: Pietarila Graham J. , Holm D. D. , Mininni P. , Pouquet A.
Published: May 2006

We present an extension of the Kármán-Howarth theorem to the Lagrangian averaged magnetohydrodynamic (LAMHD-α) equations. The scaling laws resulting as a corollary of this theorem are studied in numerical simulations, as well as the scaling of the longitudinal structure function exponents indicative of intermittency. Numerical simulations for a magnetic Prandtl number equal to unity are presented both for freely decaying and for forced two-dimensional magnetohydrodynamic (MHD) turbulence, solving the MHD equations directly, and employing the LAMHD-α equations at 1∕2 and 1∕4 resolution. Linear scaling of the third-order structure function with length is observed. The LAMHD-α equations also capture the anomalous scaling of the longitudinal structure function exponents up to order 8.
Effects of Al addition on the native defects in hafnia
Authors: Li Quan , Koo K. M. , Lau W. M. , Lee P. F. , Dai J. Y. , Hou Z. F. , Gong X. G.
Published: May 2006

Two occupied native defect bands are experimentally detected in pure HfO2. The density of states of band one in the middle of the band gap reduces drastically with the Al addition, while that of band two slightly above the valence-band maximum remains rather unaffected. We attribute the two bands to the charged oxygen vacancy, and the oxygen-interstitial-related defect states of the HfO2, respectively. We demonstrate that the added Al passivates the VO+ induced midgap states but has little effect on other aspects of the electronic structure of the material.
Grooving the carbon nanotube oscillators
Authors: Wong Lai-Ho , Zhao Yang , Chen GuanHua , Chwang Allen T.
Published: May 2006

Using microcanonical molecular dynamics, we investigate effects of single defects on the performance of a nanoscale oscillator composed of coaxial double-walled carbon nanotubes. It is found that at low temperatures a single defect placed on the outer nanotube can significantly reduces axial oscillation energy leakage by impeding intertube rotational modes, and therefore mitigates the frictional effects between sliding nanotubes.
Electric-field-induced magnetization in Pb(Zr,Ti)O3/Terfenol-D composite structures
Authors: Wan J. G. , Liu J.-M. , Wang G. H. , Nan C. W.
Published: May 2006

We report the electric-field-induced magnetization (EIM) in the composite structures made by combining Pb(Zr0.52Ti0.48)O3 (PZT) and Tb0.30Dy0.7Fe2 (Terfenol-D). The results showed that the EIM could be generated in the composite structures due to the efficient stress-mediated electromagnetic coupling interaction between the piezoelectric PZT and magnetostrictive Terfenol-D. This EIM effect depended significantly on the driving electric field frequency and was highly sensitive to the dc magnetic bias, which exhibited a promising potential in the low-level dc magnetic field detecting application.
Surface dynamics of benzenethiol molecules on Cu(111)
Authors: Wong Kin L. , Kwon Ki-Young , Bartels Ludwig
Published: May 2006

Scanning tunneling microscopy reveals that benzenethiol molecules adsorb on Cu(111) in two rotational conformations at a difference in binding energy of 0.01eV. A rotational barrier of 0.13eV allows for facile conversion between them even at cryogenic temperatures. The barrier for molecular diffusion is slightly higher at 0.15eV. Density functional theory calculations of the diffusion/translation trajectory are in good agreement with the measured barriers. These findings point to the importance of molecular dynamics for arenethiol-based molecular conductivity measurements.
Near-anode phase separation in thermally poled soda lime glass
Authors: An Honglin , Fleming Simon
Published: May 2006

Soda lime glass was thermally poled at 280°C with dc voltages up to 2kV. Second-order nonlinearity was found in a layer ∼1.7μm beneath the anode surface with second-harmonic microscopy. Scanning electron microscopy was employed to examine the microstructure of the poled glass under the anode. In the depletion region, pillar-shaped phase separations were found which could impede ion migration and enhance the stability of the induced second-order nonlinearity in the poled soda lime glass.
On the band gap of CuAlO2 delafossite
Authors: Pellicer-Porres J. , Segura A. , Gilliland A. S. , Muñoz A. , Rodríguez-Hernández P. , Kim D. , Lee M. S. , Kim T. Y.
Published: May 2006

In this letter, we discuss the electronic structure of copper aluminate (CuAlO2) on the basis of absorption measurements at low temperature and under high pressure in single crystals and thin films, combined with ab initio electronic structure calculations. The indirect character of the fundamental transition could be clearly established through the photon energy dependence of the absorption edge as measured in single crystals, yielding a band gap (plus a phonon) of 2.99±0.01eV at room temperature. An indirect excitonic structure is also observed at low temperature. The lowest energy direct allowed transition occurs near 3.53±0.01eV and is identified through its low-energy tail in single crystals and its excitonic peak in thin films. Comparing our results with ab initio calculations available in the literature, we conclude that CuGaO2 and CuInO2 can hardly be considered as wide gap semiconductors, even if they are transparent in thin films.