bluuebunny/crossref_metadata_2025_split huggingface dataset:
Plectasin – ein neues Peptidantibiotikum mit hohem therapeutischem Potential
Authors: Schmitz Jens , Holzgrabe Ulrike 
Published: September 2010

AbstractSchon länger ist bekannt, dass niedere Tiere und höhere Pflanzen endogene Peptidantibiotika exprimieren, die aktiv gegen Bakterien, Pilze und Viren sind. Einige dieser sogenannten Defensine weisen in vitro und in Tierversuchen eine hohe antibakterielle Potenz sogar gegen Antibiotika‐resistente Bakterien auf. Bonner Forschern um Tanja Schneider und Hans‐Georg Sahl gelang es kürzlich zusammen mit dänischen und niederländischen Kollegen, den neuen einzigartigen Wirkmechanismus des Defensins Plectasin aufzuklären. Dieses Peptid dient jetzt als erfolgversprechende Leitstruktur einer neuen Antibiotikaklasse.
Seizure control is important: but don't forget the patient
Authors: Johnston JA 
Published: September 2010

AbstractControl of epileptic seizures is not the only issue facing patients with epilepsy: they often suffer a range of comorbidities that affect quality of life as much as the seizures themselves. Dr Johnston explains how involving a wider multidisciplinary team of professionals in the management of patients with epilepsy can significantly improve patients' well‐being and quality of life. Copyright © 2010 Wiley Interface Ltd
The crystal structure of a bacterial Sufu‐like protein defines a novel group of bacterial proteins that are similar to the N‐terminal domain of human Sufu
Authors: Das Debanu , Finn Robert D. , Abdubek Polat , Astakhova Tamara , Axelrod Herbert L. , Bakolitsa Constantina , Cai Xiaohui , Carlton Dennis , Chen Connie , Chiu Hsiu‐Ju , Chiu Michelle , Clayton Thomas , Deller Marc C. , Duan Lian , Ellrott Kyle , Farr Carol L. , Feuerhelm Julie , Grant Joanna C. , Grzechnik Anna , Han Gye Won , Jaroszewski Lukasz , Jin Kevin K. , Klock Heath E. , Knuth Mark W. , Kozbial Piotr , Sri Krishna S. , Kumar Abhinav , Lam Winnie W. , Marciano David , Miller Mitchell D. , Morse Andrew T. , Nigoghossian Edward , Nopakun Amanda , Okach Linda , Puckett Christina , Reyes Ron , Tien Henry J. , Trame Christine B. , Bedem Henry van den , Weekes Dana , Wooten Tiffany , Xu Qingping , Yeh Andrew , Zhou Jiadong , Hodgson Keith O. , Wooley John , Elsliger Marc‐André , Deacon Ashley M. , Godzik Adam , Lesley Scott A. , Wilson Ian A. 
Published: September 2010

AbstractSufu (Suppressor of Fused), a two‐domain protein, plays a critical role in regulating Hedgehog signaling and is conserved from flies to humans. A few bacterial Sufu‐like proteins have previously been identified based on sequence similarity to the N‐terminal domain of eukaryotic Sufu proteins, but none have been structurally or biochemically characterized and their function in bacteria is unknown. We have determined the crystal structure of a more distantly related Sufu‐like homolog, NGO1391 from Neisseria gonorrhoeae, at 1.4 Å resolution, which provides the first biophysical characterization of a bacterial Sufu‐like protein. The structure revealed a striking similarity to the N‐terminal domain of human Sufu (r.m.s.d. of 2.6 Å over 93% of the NGO1391 protein), despite an extremely low sequence identity of ∼15%. Subsequent sequence analysis revealed that NGO1391 defines a new subset of smaller, Sufu‐like proteins that are present in ∼200 bacterial species and has resulted in expansion of the SUFU (PF05076) family in Pfam.
The local economic imprint of return migrants in Bolivia
Authors: Jones Richard C. 
Published: September 2010

AbstractUntil recently the role of international return migrants in local economic development has received little attention from researchers. Drawing upon Granovetter's notion of embeddedness and Levitt's concept of social remittances, I argue that return migrants are more locally embedded (in terms of local networks and cultural affinity) and better able to transfer social remittances (skills, social capital, and norms) from abroad, than active migrants. Therefore, I expect they will have a larger economic imprint (i.e., work, spend, and invest locally to a higher degree) than either non‐migrants or active migrants. To test this expectation, I rely on my 2007 survey of over 400 households in the Valle Alto of Bolivia – a country where remittances from foreign labor migration have taken on great importance in recent years. I compare three types of households: (1) active migrant households, in which at least one member is working overseas; (2) return migrant households, in which at least one member has returned from overseas and there are no active migrants; and (3) non‐migrant households, in which no one has ever worked abroad. The results suggest that return migrant households work and invest locally and contribute more to the economic base of their home communities than either of the other two types; and that this is made possible by the combination of their local embeddedness and their use of social remittances to further their economic success in Bolivia. Copyright © 2010 John Wiley & Sons, Ltd.
Raman diagnostics of multi‐wall carbon nanotubes with a small wall number
Authors: Bokova S. N. , Obraztsova E. D. , Grebenyukov V. V. , Elumeeva K. V. , Ishchenko A. V. , Kuznetsov V. L. 
Published: September 2010

AbstractRaman spectroscopy study of multi‐wall carbon nanotubes (MWNTs) of different diameters (with a small controllable number of walls) produced using Fe–Co catalyst with a variable size of the same active component has been performed. We have characterized as produced MWNTs with different diameters (series 1) and two types of tubes with fixed mean diameters (∼10 and 20 nm) heated in a flow of pure argon at various temperatures (2200, 2600 and 2800 °C – series 2). The Raman spectra of MWNTs have been registered in three spectral regions, corresponding to D (disorder‐induced), G (graphite) and 2D (two‐phonon scattering) bands. A ratio of intensities I2D/ID for tubes of series 1 has demonstrated almost a linear dependence on the nanotube diameter. After heating (series 2), D (disorder‐induced) Raman band has shown a substantial decrease in intensity. The variation of the Raman spectra parameters is discussed in terms of defectiveness of nanotubes.
Nitrogen‐doped SWCNT synthesis using ammonia and carbon monoxide
Authors: Susi Toma , Zhu Zhen , Ruiz‐Soria Georgina , Arenal Raul , Ayala Paola , Nasibulin Albert G. , Lin Hong , Jiang Hua , Stephan Odile , Pichler Thomas , Loiseau Annick , Kauppinen Esko I. 
Published: September 2010

AbstractGreat effort has been directed into modifying the electrical properties of produced carbon nanotubes by chemical doping and – in parallel – into controlling their chirality. We present a new approach to synthesizing nitrogen‐doped single‐walled carbon nanotubes (SWCNTs), based on gas phase floating catalyst CVD. The nitrogen content in the tubes was verified by transmission electron microscopy/electron‐energy loss spectroscopy (TEM/EELS), and their chiral angle distribution found by electron diffraction (ED) to be skewed toward armchair tubes. Additionally, the optical properties of the material were probed by multi‐frequency Raman spectroscopy and optical absorption.
Optoelectronic studies of boron nitride nanotubes and hexagonal boron nitride crystals by photoconductivity and photoluminescence spectroscopy experiments
Authors: Brasse Gurvan , Maine Sylvain , Pierret Aurélie , Jaffrennou Périne , Attal‐Trétout Brigitte , Ducastelle Francois , Loiseau Annick 
Published: September 2010

AbstractThe optoelectronic properties of hexagonal boron‐nitride and boron‐nitride nanotubes (BNNTs) are investigated by using photoconductivity experiments, associated to photoluminescence excitation analysis. By this way, excitations related to the conduction band of hexagonal boron‐nitride have been experimentally determined, as well as the free excitonic level. Multiwalled boron‐nitride nanotubes have also been lead by using these methods and the first results suggest some hypotheses about the band gap energy and the nature of the various absorptions, which occur under an UV excitation. These experimental results are presented and discussed and some perspectives are finally suggested.
The effect of carvacrol on muscarinic receptors of guinea‐pig tracheal chains
Authors: Boskabady M. H. , Jafari Z. , Pouraboli I. 
Published: September 2010

AbstractThe effects of three concentrations of carvacrol, the constituent ofZataria multifloraBoiss (a monoterpenoid phenol, C10H14O) and 10 nmatropine on muscarinic receptors were tested on: non‐incubated (n= 7), incubated tracheal chains with propranolol and chlorpheniramine (n= 6) and incubated with propranolol (n= 5). The EC50of all three concentrations of carvacrol in incubated tissues with propranolol and chlorpheniramine was significantly greater than those of incubated tissues with propranolol and non‐incubated trachea (p< 0.05 top< 0.001). The EC50of two higher concentrations of carvacrol (0.2 and 0.4 µg/mL) in incubated tissues with propranolol was also significantly greater than those of non‐incubated trachea (p< 0.01 top< 0.001). The maximum response in the presence of all concentrations of carvacrol in non‐incubated and incubated tissues with propranolol and chlorpheniramine and those of its two higher concentrations (0.2 and 0.4 µg/mL) in incubated tissues with propranolol were lower than saline (p< 0.05 top< 0.001). There were parallel rightward shifts in the concentration–response curves in the presence of all concentrations of carvacrol in non‐incubated and incubated tissues with propranolol and its lower concentration in incubated tissues with propranolol and chlorpheniramine. These results indicated an inhibitory effect of carvacrol on muscarinic receptors. A β‐adrenoceptor stimulatory effect was also suggested for carvacrol. Copyright © 2010 John Wiley & Sons, Ltd.
Novel photocyclization of β,γ‐unsaturated oximes
Authors: Armesto Diego , Ramos Ana , Ortiz Maria J. , Mancheño Maria J. , Mayoral Elena P. 
Published: September 2010

AbstractPreviously, β, γ‐unsaturated oximes were thought to be photochemically unreactive. The present study reports the first three examples of photocyclization of β,γ‐unsaturated ketoximes to yield 4,5‐dihydroisoxazole derivatives. Typically, acetophenone‐sensitized irradiation of 3,3‐dimethyl‐5,5‐diphenylpent‐4‐en‐2‐one oxime (2) affords 5‐(diphenylmethyl)‐3,4,4‐trimethyl‐4,5‐dihydroisoxazole (3) in 38% yield. A single‐electron transfer (SET) mechanism is proposed to account for the cyclization.
Rapid intramolecular and C‐O cleavage reactions of a phosphate triester catalysed by a neighbouring hydroxyl group
Authors: Kirby Anthony J. , Marriott Robert E. 
Published: September 2010

AbstractThree consecutive reactions are observed when the phosphate triester 6 is hydrolysed. At pH < 7 rapid cyclisation gives the triester 12, with the loss of the hemiacetal leaving group (3,4‐dichlorophenoxy)methanol (which rapidly breaks down to the phenol). The effective molarity of the neighbouring OH group is of the order of 1012 M. 12 is then hydrolysed by C‐O cleavage to give the diester 11. In base, the first two reactions are complete almost instantaneously, and the final phosphorus‐containing products are (3,4‐dichlorophenoxy)methyl methyl phosphate diester, and the methyl phosphate dianion. These must come from C‐O cleavage reactions of diester 14 and the rearranged benzylic triester 15, which rapidly eliminate phosphate ester leaving groups to give the same quinone methide.
Axially chiral 2‐(dialkylamino)benzamides. Barriers to rotations, determined by NMR and by racemization (neighboring rotor substituents on arene systems, part 3)
Authors: Kiefl C. , Zinner H. , Burgemeister T. , Mannschreck A. 
Published: September 2010

AbstractThe title compounds (Scheme 1, Y = NMe2) were investigated by variable‐temperature NMR and/or by racemization of enantiomers enriched by liquid chromatography on microcrystalline triacetylcellulose. For several reasons, a dialkylamino and a dimethylcarbamoyl group were used, for the first time, as neighboring rotor substituents on a benzene ring. Barriers to rotations about their aryl‐nitrogen and/or aryl‐carbon bonds were determined and assigned (Table I). Correlated or uncorrelated motions of these groups are possible for amides 11 and 19 bearing in their 3‐positions tert‐butyl substituents which hinder the aryl‐nitrogen rotation. Uncorrelated rotations have been found for amide 15 (Figure 2) and thioamide 8 which have the less voluminous bromine atom in their 3‐position.
Oxidation of different sugar residues catalyzed by [Ru(azpy)2(H2O)2]2+; A comparative study
Authors: Boelrijk Alexandra E. M. , Dorst J.(Hans) T. , Reedijk Jan 
Published: September 2010

AbstractThe oxidation of several sugars by NaBrO3 catalyzed by [Ru(azpy)2(H2O)2]2+, is reported and compared with earlier oxidation results with octyl α‐D‐glucoside (α‐OGP). The sugars studied were 1‐octyl β‐D‐glucoside (β‐OGP), 1‐octyl β‐D‐galactoside (β‐OGaP), 1‐phenyl β‐D‐glucoside (β‐PGP), 1‐methyl α‐D‐glucoside, 1‐methyl β‐D‐glucoside and 1‐decyl β‐D‐maltoside (β‐DMP). The results with β‐DMP are compared with previously reported oxidation results with β‐DMP heterogeneously catalyzed over platinum. The structure of the sugar substrate appears to have a significant effect on the activity and selectivity of the oxidation reaction. The main conclusions from this study are that β‐isomers are in general less reactive than α‐isomers; β‐PGP in particular is very unreactive. The kind of substitution (phenyl versus alkyl, octyl versus methyl) on the anomeric centre has considerable effect on the reactivity of the sugar. The oxidation of β‐DMP catalyzed by [Ru(azpy)2(H2O)2]2+ results in a number of different oxidation products. The C6‐primary hydroxy groups of both glucose units of β‐DMP can be oxidized to carboxylic groups, in contrast to the previously reported heterogeneous catalyzed oxidation of β‐DMP by dioxygen. However, the main reaction is the splitting of the decyl chain from the maltose unit. The α‐1,4‐O link between the glucose units appears to be quite stable under the catalytic oxidation conditions used. Based on the results obtained, possible reaction mechanisms are discussed.
Molybdenum‐catalyzed epoxidations of oct‐1‐ene and cyclohexene with organic hydroperoxides: Steric effects of the alkyl substituents of the hydroperoxide on the reaction rate
Authors: Lempers H.E.B. , van Crey M.J. , Sheldon R.A. 
Published: September 2010

AbstractA kinetic study of the epoxidation of oct‐1‐ene and cyclohexene with alkyl hydroperoxides is reported. The alkyl hydroperoxides were obtained in a moderate to high purity from the corresponding alcohols by acid‐catalyzed exchange with hydrogen peroxide. The reaction rates in pseudo first‐order experiments of these olefins with various alkyl hydroperoxides strongly depend on the structure of the alkyl group of the alkyl hydroperoxide. When one of the methyl groups in tert‐butyl hydroperoxide (TBHP, 4a) is substituted by an alkyl group, R, the reaction rate decreases in the order Et > Pr > Bu >1 BuCH2 > tBu. Substitution of two methyl groups of TBHP as in 1‐ethyl‐1‐methylpropyl hydroperoxide (5a) and 1‐ethyl‐1‐methylbutyl hydroperoxide (5b) showed a further decrease in reaction rate of epoxidation. When all three methyl groups are substituted by, for example, three ethyl groups as in 1,1‐diethylpropyl hydroperoxide (6a) a decrease of approximately 99% in reaction rate is observed. Introduction of a ring system in the hydroperoxide such as in cyclohexyl hydroperoxide (3), 1‐methyl‐cyclohexyl hydroperoxide (2) and pinane hydroperoxide (1) also showed a dramatic decrease in reaction rate of epoxidation.An investigation of relative rates of epoxidation in competition experiments of cyclohexene and hex‐1‐ene with 1‐tert‐butylcyclohexene with different alkyl hydroperoxides also showed them to depend on the structure of the alkyl group of the alkyl hydroperoxide.These results are rationalized on the basis of a mechanism involving nucleophilic attack of the olefin on an alkylperoxomolybdenum(VI) intermediate. Bulky substituents at the α‐position in the alkyl hydroperoxide can seriously impede the approach of the olefin to the O‐O bond.
A review on scale and siting of wind farms in China
Authors: Deng Yuanchang , Yu Zhi , Liu Sha 
Published: September 2010

AbstractUsing a wind power information system, which is based on the geographic information system (GIS), this paper presents a statistical analysis of built and approved wind farms to the end of 2008. The average capacity of wind turbine generators (WTGs) and the scale of wind farms are investigated. The geographical distribution of wind farms and the main factors affecting wind farm siting are analysed. The results show: (i) The average capacity of WTGs is increasing; MW scale WTGs have become the mainstream product in the China market. (ii) Because of the national wind project approval policy, most of the wind farms have installed capacities of just under 50 MW. (iii) When siting a wind farm, wind resource is still the predominant factor being considered, while grid connection is still the main constraint in this stage. (iv) Concerning land use, among the wind farms built by 2008, 40% use grasslands, 31% use agricultural land, 17% use desert or bare lands, while 12% use farmlands. (v) Statistics show 88.6% of the built wind farms have elevation change of less than 300 m, and 90% of the built wind farms have GIS slopes of less than 10°. (vi) The geographical distribution of wind farms reveals a highly concentrated deployment tendency, 58.7% of all the newly built wind farms in 2008 are within 10 km of existing wind farms. Copyright © 2010 John Wiley & Sons, Ltd.
Viral tRNAs and tRNA‐like structures
Authors: Dreher Theo W. 
Published: September 2010

AbstractViruses commonly exploit or modify some aspect of tRNA biology. Large DNA viruses, especially bacteriophages, phycodnaviruses, and mimiviruses, produce their own tRNAs, apparently to adjust translational capacity during infection. Retroviruses recruit specific host tRNAs for use in priming the reverse transcription of their genome. Certain positive‐strand RNA plant viral genomes possess 3′‐tRNA‐like structures (TLSs) that are built quite differently from authentic tRNAs, and yet efficiently recapitulate several properties of tRNAs. The structures and roles of these TLSs are discussed, emphasizing the variety in both structure and function. © 2010 John Wiley & Sons, Ltd.This article is categorized under:

RNA Structure and Dynamics > Influence of RNA Structure in Biological Systems
RNA Interactions with Proteins and Other Molecules > Protein–RNA Interactions: Functional Implications
Translation > Translation Regulation
RNA Processing > tRNA Processing
Quantitative analysis of phosphorylation‐based protein signaling networks in the immune system by mass spectrometry
Authors: Nita‐Lazar Aleksandra 
Published: September 2010

AbstractDynamic modification of cell proteins with phosphate is one of the key regulators of the cellular response to external stimuli. Phosphorylation‐based signaling networks mediate cell proliferation, differentiation, and migration, and their dysregulation is the basis of multiple diseases. However, the transient nature of the regulatory protein phosphorylation and low site occupancy mean that only a fraction of the protein is phosphorylated at a given time, and it is a challenge to measure the degree and dynamics of phosphorylation using traditional biochemical means. Technological advances in the field of mass spectrometry (MS) made it possible to generate large sets of phosphoproteomics data, probing the phosphoproteome with great depth, sensitivity, and accuracy. Therefore, quantitative phosphoproteomics emerged as one of the essential components of the systems biology approach for profiling of complex biological networks. Nowadays, the challenge lies in validation of the information and in its integration into the comprehensive models of cell decision processes. This article reviews the role of phosphoproteomics in systems biology, the MS‐based approach, and technical details of the methods. Recent examples of quantitative measurements and methodologies as well as applications to the studies of the immune system and infectious diseases are presented and discussed. WIREs Syst Biol Med 2011 3 368–376 DOI: 10.1002/wsbm.123This article is categorized under:

Laboratory Methods and Technologies > Proteomics Methods
Zur Methodik der Absorptions‐ und Reflexionsspektroskopie extrem sauerstoffempfindlicher Verbindungen
Authors: König E. , Schläfer H. L. , Herzog S. 
Published: September 2010

AbstractDie Möglichkeiten smr Aufnahme von Absorptions‐ und Reflexionsspektren extrem sauerstoffempfindlicher Verbindungen werden beschrieben. Außerdem werden die dazu notwendigen apparativen Hilfsmittel sowie geeignete Verfahren zur Lösungsmittelreinigung angegeben.
Kalorimetrie kristallin‐flüssiger Substanzen Kalorische Daten und molekulare Wechselwirkung in der Reihe der Dialkoxyazoxybenzole
Authors: Arnold H. 
Published: September 2010

AbstractIm Hinblick auf die Besonderheiten der molekularen Ordnung in kristallinen Flüssigkeiten wird für die homologe Reihe der 4,4′‐Di‐n‐alkoxy‐azoxybenzole eine vergleichende Betrachtung der Molwärmen im kristallinfesten, smektischen, nematischen und isotrop‐flüssigen Zustand sowie der latenten Wärmen der Phasenübergänge vorgenommen. Eine Gegenüberstellung mit den Aussagen der molekularstatistischen Theorie vonMaierundSaupeüber die nematischen Phasen ergibt, daß der Anstieg der Molwärmen unterhalb der Klärpunktstemperatur als Auswirkung eines verstärkten Abbaus der kristallin‐flüssigen Ordnung gedeutet werden kann. Für die Umwandlungswärme am Klärpunkt zeigt sich beim Dimethoxyazoxybenzol eine größenordnungsmäßige Übereinstimmung, während der Gang der Werte beim Fortschreiten in der homologen Reihe durch die Theorie nicht befriedigend wiedergegeben wird.
Synthesen mit α‐Halogenäthern
Authors: Groβ Hans , Höft Eugen , Rieche A. 
Published: September 2010

Abstractα‐Halogenäther sind seit langem in verschiedenen Arbeitskreisen untersucht worden. Dabei wurde gefunden, daß diese Verbindungsklasse auf Grund ihrer besonderen Reaktionsfähigkeit als präparative Hilfsmittel bzw. als Zwischenprodukte für eine ganze Reihe verschiedener Synthesen eingesetzt werden können. Die Chemie der α‐Halogenäther wurde mehrfach unter verschiedenen Gesichtspunkten zusammengefaßt, so z. B. von Summers [1], Baganz [2], Issaguljanz und Below [3] sowie von Groβ und Höft [4]. In neuerer Zeit wurden von mehreren Seiten interessante neue Anwendungsmöglichkeiten gefunden, so daß eine Zusammenfassung der Reaktionsmöglichkeit der α‐Halogenäther sowie in einigen Fällen auch der ganz analog reagierenden α‐Halogenester, α‐Halogencarbonate und α‐Halogenthioäther gerechtfertigt erscheint. In dem vorliegenden Überblick wurde besonderer Wert auf solche Reaktionen gelegt, die im organisch‐präparativen Maßstab von Interesse sind. Ältere Arbeiten konnten hier z. T. nicht berücksichtigt werden. Hierzu sei auf die nahezu vollständige Literaturübersicht der Arbeiten über α‐Halogenäther von Summers verwiesen (Literatur bis Anfang 1954). α‐Fluoräther zeigen allgemein gegenüber den anderen Halogenäthern ein abweichendes Reaktionsverhalten. Sie werden deshalb in dieser Zusammenfassung nicht berücksichtigt.
Über Substituenten‐Konstanten
Authors: Schott Günther 
Published: September 2010

AbstractEs wird ein Überblick über die zahlreichen in der Literatur enthaltenen Varianten von σ‐Konstanten gegeben. Die verschiedenen σ‐Konstanten werden hinsichtlich ihrer Anwendungsbereiche verglichen und ihre gegenseitigen Beziehungen werden untersucht. Mit der vorliegenden Übersicht wird eine nachfolgende Veröffentlichung [1] vorbereitet, in der die Anwendbarkeit von σ‐Konstanten zur Beurteilung der Reaktionsfähigkeit von Organo‐Silicium‐Verbindungen behandelt wird.