bluuebunny/crossref_metadata_2025 huggingface dataset:
Retinoid ameliorates experimental autoimmune myositis, with modulation of Th cell differentiation and antibody production in vivo
Authors: Ohyanagi Naho , Ishido Miwako , Suzuki Fumihito , Kaneko Kayoko , Kubota Tetsuo , Miyasaka Nobuyuki , Nanki Toshihiro
Published: September 2009

Objective

Polymyositis and dermatomyositis are chronic inflammatory muscle diseases. Retinoids are compounds that bind to the retinoic acid binding site of retinoic acid receptors and have biologic activities similar to those of vitamin A. Recent studies indicate that retinoids promote Th2 differentiation and suppress Th1 and Th17 differentiation in vitro. The present study was undertaken to examine the effects of a synthetic retinoid, Am80, on experimental autoimmune myositis as well as on Th phenotype development and antibody production.

Methods

Experimental autoimmune myositis was induced in SJL/J mice by immunization with rabbit myosin. Am80 was administered orally once daily. Its effects were evaluated by measurement of the numbers of infiltrating inflammatory cells, production of inflammatory cytokines in muscle, production of Th‐specific cytokines by myosin‐stimulated splenic T cells, and production of antimyosin antibodies in serum.

Results

In mice with experimental autoimmune myositis, orally administered Am80 significantly reduced the number of infiltrating inflammatory cells and the expression of tumor necrosis factor α and interleukin‐1β (IL‐1β) in muscle. Moreover, Am80 increased production of interferon‐γ, IL‐4, and IL‐10, but not IL‐17, by myosin‐stimulated splenic T cells of mice with experimental autoimmune myositis, suggesting that it could enhance differentiation into Th1 and Th2, but not Th17, in vivo. Am80 also decreased serum levels of IgG2a and IgG2b antimyosin antibodies, but did not affect levels of IgG1 antimyosin antibodies. In addition, it suppressed chemokine expression and activator protein 1 activity in myoblasts in vitro.

Conclusion

The synthetic retinoid Am80 has an inhibitory effect on experimental autoimmune myositis. It might regulate the development of Th phenotype and antibody production in vivo, in addition to its effects on cytokine and chemokine production.
Kippsicherheitsnachweis für Stahlbeton‐ und Spannbetonbinder
Authors: Hölter Dirk
Published: September 2009

In der Literatur finden sich verschiedene Normen und Richtlinien sowie verschiedene Theorien und Berechnungsansätze, um den Nachweis der Kippsicherheit für Binder führen zu können. Bei nahezu allen Veröffentlichungen ist für den Praktiker nicht auf einen Blick ersichtlich, ob überhaupt eine Untersuchung der Kippsicherheit erforderlich ist.

Wenn die Kippsicherheit maßgeblich wird, gilt es zu beurteilen, welche Maßnahmen zum Erreichen der Kippsicherheit untersucht werden müssen. Hier soll der folgende Beitrag Transparenz schaffen.
Zur sinnvollen Anwendung ganzheitlicher Gebäudemodelle in der Tragwerksplanung von Hochbauten
Authors: Fastabend Michael , Schäfers Tobias , Albert Mark , Lommen Hans‐Gerd
Published: September 2009

Ausgehend von den kritischen Randbedingungen der Berechnung mit ganzheitlichen Gebäudemodellen werden typische und häufig anzutreffende Konstruktionsfälle diskutiert, bei denen Gesamtmodelle Vorteile für den Entwurf aufzeigen. Hier sind räumliche Tragwirkungen zu nennen, die Erfassung von Zwangsbeanspruchungen bei komplexen Grundrissen mit vielfältigen Festhaltungen sowie die Beanspruchung schlanker Gebäudestrukturen aus Windlasten und seismischen Einwirkungen. Für die genannten sinnvollen Anwendungsfälle werden die notwendigen Randbedingungen diskutiert. Die jeweiligen Anwendungsfälle werden anhand konkreter Gebäudebeispiele vorgestellt.

On the reasonable use of total building models in the design of building structures

Coming from the critical boundary conditions of the calculation with total building models, typical and prevalent constructions, where total models show advantages for the design, will be discussed. Here, spatial load‐bearing impact, the registration of unforced interactions of complex ground plans with various supports as well as the stressing of slender building structures resulting from wind loads and seismic impacts have to be mentioned. For the stated reasonable use cases the necessary boundary conditions will be discussed. The respective use cases will be presented by means of concrete building examples.
Vergleich statischer und dynamischer Methoden zur Zustandsbewertung von Stahlbeton‐ und Spannbetontragwerken
Authors: Waltering Markus , Bungard Volker , Waldmann Danièle , Maas Stefan , Zürbes Arno
Published: September 2009

Risse in Stahlbeton‐ und Spannbetontragwerken führen zu einem Steifigkeitsverlust, der die statischen und dynamischen Eigenschaften der jeweiligen Struktur beeinflusst. Eine klassische Methode zur Bestimmung statischer Kennwerte sind Probebelastungen, bei denen gemessene Verformungen mit rechnerischen Werten abgeglichen werden und somit einen Rückschluss auf die Tragfähigkeit der Struktur ermöglichen. Bei Bauwerken wie Brücken können derartige Tests sehr kosten‐, zeit‐ und materialaufwändig sein und erfordern häufig eine längerfristige Sperrung. Des Weiteren müssen die gemessenen Verformungen vor Ort durch erfahrene Ingenieure überwacht werden, um gegebenenfalls bei Überschreiten kritischer Werte den Test abzubrechen. Auch die dynamischen Eigenschaften von Strukturen werden maßgeblich durch die Steifigkeit beeinflusst und können in vielen Fällen schnell und mit wenig Aufwand bestimmt werden. Im Rahmen dieses Aufsatzes werden die Ergebnisse statischer und dynamischer Untersuchungen zur Zustandsbewertung, durchgeführt an Stahlbeton‐ und Spannbetonbauteilen im Labor und an einer schrittweise geschädigten Spannbetonbrücke, hinsichtlich ihrer Sensibilität auf Schäden und Handhabbarkeit in der praktischen Anwendung gegenübergestellt.

Comparison of Static and Dynamic Methods to Assess the State of Reinforced and Prestressed Concrete Structures

Cracks in reinforced and prestressed concrete structures lead to a reduction in stiffness and therefore to an influence on the static and dynamic properties. A conventional method to assess the static characteristics are static load tests which enable to correlate measured deformations with calculated values and to draw conclusions about the loading capacity. In case of bridges, these tests can be very cost‐intensive and time‐consuming and often require a closure of the bridge. Furthermore the measured deformations have to be examined in situ, in order to abort the test if the deformations exceed critical values. As well, the dynamic properties are affected by changes in stiffness and in many cases they can be quickly determined without large effort. Within this article the results of static and dynamic tests with laboratory reinforced and prestressed concrete structures and tests on a gradually damaged prestressed concrete bridge are presented. The results are compared with regard to the sensitivity of the different methods to damage.
Hochleistungsleichtbeton unter mehraxialer Druckbeanspruchung
Authors: Scheerer Silke , Hampel Torsten , Curbach Manfred
Published: September 2009

An vielen Stellen im Tragwerk herrschen mehraxiale Spannungszustände. Ob sich die Tragfähigkeit von Hochleistungsleichtbetonen unter mehraxialer Druckbeanspruchung ebenso erhöht wie bei Normalbetonen, wurde in zwei‐ und dreiaxialen Tests untersucht. Es wurde ein Bruchkriterium für Leichtbetone abgeleitet und Parallelen und Unterschiede zu Normalbeton aufgezeigt.

High Performance Lightweight Aggregate Concrete under Multiaxial Compression

There are multiaxial stress conditions at many points in a structure. Whether the strength of high performance lightweight concrete under multiaxial compression increases as well as the strength of normal concrete, was verified in bi‐ and triaxial tests. A failure criterion for lightweight concrete was derived and analogies and differences to normal oncrete were pointed out.
Querkrafttragfähigkeit von Fahrbahnplatten ohne Querkraftbewehrung
Authors: Rombach Günter , Latte Sören
Published: September 2009

Es wird über Versuche zur Querkrafttragfähigkeit von Brückenfahrbahnplatten aus Stahlbeton berichtet. Diese zeigen, dass die bekannten Rechenansätze für Bauteile ohne Querkraftbewehrung nach DIN 1045‐1 bzw. DIN‐FB 102 für Fahrbahnplatten auf der sicheren Seite liegen, die tatsächliche Tragfähigkeit aber weit unterschätzt wird. Weitere Ansätze zur Berechnung der Querkrafttragfähigkeit von Stahlbetonbauteilen ohne Querkraftbewehrung werden erörtert. Während die Modelle bei der Auswertung einer Datenbank von Balkenversuchen eine gute Übereinstimmung aufweisen, zeigt der Vergleich mit den Modellversuchen, dass die meisten Rechenverfahren die Tragfähigkeit der Platten unterschätzen. Zur Berechnung der Querkrafttragfähigkeit von Platten ohne Querkraftbewehrung unter Punktlasten wird ein Modell vorgeschlagen, welches die Querkrafttragfähigkeit mit der Zugbeanspruchung der Biegezugzone im kritischen Bereich verknüpft.

Shear Resistance of Bridge Decks without Transverse Reinforcement

The design of concrete bridge deck slabs is of major concern since the introduction of the Eurocodes as the calculated shear capacity of slabs without stirrups and staggered reinforcement according to the new design standards is often considerably smaller compared to the former regulations i.e. DIN 1045:88. This raises the question whether the existing structures are still save. A series of 12 tests on 4 different specimens representing a bridge deck was performed to examine the real load bearing behaviour of a slab with and without shear reinforcement under a wheel (point) load. The evaluation of the test results revealed, that the current design formula with an assumed elastic shear force distribution leads to rather conservative values of shear capacity for bridge deck slabs. Various approaches for shear design are discussed and the accuracy is checked by means of a shear database and the test results. A new model to calculate the shear capacity is proposed which shows a better agreement with test data than the known approaches.
Zustandsermittlung und Schadensdiagnose für Parkhäuser mit automatisierten zerstörungsfreien Prüfverfahren
Authors: Stoppel Markus , Taffe Alexander , Reichling Kenji , Kurz Jochen
Published: September 2009

Verkehrsbauwerke sind oft besonders widrigen Umgebungsbedingungen ausgesetzt. Dies gilt besonders für Parkhäuser und ‐garagen. Zu einer hohen Chloridbelastung, mechanischer Beanspruchung und Frost‐Tauwechsel Beanspruchung kommen gerade bei Bauwerken aus den 1970er und 1980er Jahren baulich bedingte Schwachstellen wie zu geringe Betondeckung, unzureichende Entwässerungsvorrichtungen, fehlende Abdichtungen und schlecht nachbehandelter Beton an der Oberfläche. Erschwerend kommt hinzu, dass nicht alle Schäden visuell von außen erkennbar sind. Für solche Bauwerke muss der sachkundige Planer zusammen mit dem Bauherren wichtige Entscheidungen treffen. Lohnt eine Instandsetzung? Wenn ja, wie umfangreich muss sie sein, damit sie auch dauerhaft ist? Wie stark ist die Konstruktion geschädigt? Die Fragen müssen zuverlässig beantwortet werden, um eine bedarfsgerechte Instandsetzung sicherzustellen. Dazu hat sich die Kombination verschiedener zerstörungsfreier Verfahren als sinnvoll erwiesen. So werden an jedem Messpunkt eines umfangreichen Messrasters am Bauwerk Messwerte verschiedener Verfahren im Sinne ergänzender Untersuchungen aufgezeichnet. Zur Beantwortung der Frage, ob an einer Stelle tatsächlich mit Korrosion zu rechnen ist, werden z. B. die Messwerte der Potentialfeldmessung mit Betondeckungsmessungen und Feuchtemessungen kombiniert. Um die Kombination solcher Verfahren in einem ausreichend dichtem Messraster und dennoch schnell durchführen zu können wird in dem Beitrag über ein selbstnavigierendes Robotersystem berichtet, das modular mit bis zu sechs Verfahren bestückt ist und um weitere Verfahren erweitert werden kann. Bei der Darstellung der Ergebnisse wurde besonders darauf geachtet, diese für großflächige Bereiche so darzustellen, dass eine vergleichende Betrachtung möglich ist.
Ligand‐Centred Reactivity of Bis(picolyl)amine Iridium: Sequential Deprotonation, Oxidation and Oxygenation of a “Non‐Innocent” Ligand
Authors: Tejel Cristina , del Río M. Pilar , Ciriano Miguel A. , Reijerse Eduard J. , Hartl František , Záliš Stanislav , Hetterscheid Dennis G. H. , Tsichlis i Spithas Nearchos , de Bruin Bas
Published: September 2009

Treatment of [Ir(bpa)(cod)]+ complex [1]+ with a strong base (e.g., tBuO−) led to unexpected double deprotonation to form the anionic [Ir(bpa−2H)(cod)]− species [3]−, via the mono‐deprotonated neutral amido complex [Ir(bpa−H)(cod)] as an isolable intermediate. A certain degree of aromaticity of the obtained metal–chelate ring may explain the favourable double deprotonation. The rhodium analogue [4]− was prepared in situ. The new species [M(bpa−2H)(cod)]− (M=Rh, Ir) are best described as two‐electron reduced analogues of the cationic imine complexes [MI(cod)(Py‐CH2‐NCH‐Py)]+. One‐electron oxidation of [3]− and [4]− produced the ligand radical complexes [3]. and [4].. Oxygenation of [3]− with O2 gave the neutral carboxamido complex [Ir(cod)(py‐CH2‐N‐CO‐py)] via the ligand radical complex [3]. as a detectable intermediate.
An Unusual N‐Boc Deprotection of Benzamides under Basic Conditions
Authors: Yin Biaolin , Zhang Yuanxiu
Published: September 2009

For the first time, an unusal cleavage of N‐tert‐butyloxycarbonyl (N‐Boc) protection from N‐Boc‐protected benzamide under basic conditions in excellent yields is reported. The deprotection involves the N‐Boc emigration from the benzamide to form 2‐O‐Boc group followed by O‐Boc deprotection on the phenyl ring.
Novel Metal Oxide Support with Water Activation Ability for Use in Direct Methanol Fuel Cell
Authors: Wang Qingjing , Wei Ang , Zhao Xiaohui , Zhang Shuyong
Published: September 2009

A new principle for designing catalyst supports with water activation ability was proposed. According to this principle, stabilized nickel(+3) oxides with different dopants were tested as possible support and promoter for Pt catalyst in direct methanol fuel cells. It was found that the chemical and electrochemical stabilities of these novel supports in acidic solution were sufficient. The support doped with Al(+3) has catalytic activity towards methanol electrooxidation while that doped with Co(+3) can improve both activity and poisoning tolerance of the Pt catalyst.
Antibacterial Properties of a Kind of Schiff Base and Its Neodymium(III) and Zn(II) Complex (ZnNdL) on Escherichia coli
Authors: Li Chaohong , Zhu Juncheng , Qi Zude , Hou Hanna , Hu Yanjun , Liu Yi
Published: September 2009

The microcalorimetric and electronic microscopy methods were used to study the antibacterial activity of a Schiff base and its complex ZnNdL on Escherichia coli. The metabolic power‐time curves of the bacteria treated with the compounds were obtained, and the thermokinetic parameters were analyzed. The results show that the compounds (H2L, ZnNdL) have good activity on aerobic multiplying metabolism of E. coli, with the values of IC50 57.0 and 54.4 mg·L−1, respectively. In order to further investigate their mechanism on E. coli, transmission electronic microscopy and scanning electronic micrography were used to study the cell membrane change induced by the dibasic quadridentate Schiff base and its neodymium(III) complex. At a low concentration of the compound, the flagellum was inhibited and the cell did not show distinct changes. However, the flagella around the cell membrane were exfoliated, the morphology of E. coli was changed from a rod shape into a spherical shape or a short rod, and the flagella disappeared completely at a high concentration. The drug permeability into cell membrane was investigated by fluorescence quenching of probe dis‐C3‐(5), which suggested that H2L and ZnNdL could influence on the intra and extra cell membrane.
Theoretical Studies on the Structures, Stabilities, Vibrational Spectra, and Thermodynamic Properties of Polynitromethylbenzenes
Authors: Wang Guixiang , Gong Xuedong , Liu Yan , Xiao Heming
Published: September 2009

The nitro derivatives of methylbenzenes were optimized to obtain their molecular geometries and electronic structures at the DFT‐B3LYP/6‐31G* level. The structure parameters, such as the C–NO2 bond length (L) and the least C–NO2 bond overlap population (M) were focused to predict their relative stability or sensitivity. Their IR spectra were obtained and assigned by vibrational analysis, which are reliable compared with the experimental results. Based on the frequencies scaled by 0.96 and the principle of statistic thermodynamics, the thermodynamic properties were evaluated, which are linearly related with the number of nitro and methyl groups as well as the temperature, obviously showing good group additivity.
Synthesis, Characterization and Thermodynamic Study of the Solid State Coordination Compound Ni(Nic)2·H2O(s) (Nic=Nicotinate)
Authors: Chen Jingtao , He Donghua , Di Youying , Kong Yuxia , Yang Weiwei , Dan Wenyan , Tan Zhicheng
Published: September 2009

A novel compound‐monohydrated nickel nicotinate was synthesized by the method of room temperature solid phase synthesis and ball grinder. FTIR, chemical and elemental analysis, TG/DTG, and X‐ray powder diffraction technique were applied to characterize the structure and composition of the coordination compound. Low‐temperature heat capacities of the solid coordination compound have been measured by a precision automated adiabatic calorimeter over the temperature range from 78 to 386 K. A solid‐solid phase transition occurred in the temperature range of 328–358 K in the heat capacity curve, and the peak temperature, the molar enthalpy and molar entropy of the phase transition were determined to be Ttrs=(356.759±0.697) K, ΔtrsHm=(13.650±0.408) kJ·
mol−1, and ΔtrsSm= (38.279±0.086) J·K−1·mol−1, respectively. The experimental values of the molar heat capacities in the temperature ranges of 78–328 K and 358–386 K were fitted to two polynomials, respectively. The polynomial fitted values of the molar heat capacities and fundamental thermodynamic functions of the sample relative to the standard reference temperature 298.15 K were calculated and tabulated at the intervals of 5 K.
Immersion Deposition of Pt Nanoparticles on Porous Silicon for Methanol Oxidation
Authors: Su Xu , LÜ Kangle , Chang Yanlong , Zhang Yan , Wang Chunming
Published: September 2009

Porous silicon (PS) was chosen as the substrate for supporting the Pt particles because of great surface area, good conductivity and stability. Pt nanoparticles have been successfully prepared on the substrate by immersion deposition, which is convenient. The component and morphological properties of the films have been investigated by means of X‐ray diffraction (XRD), energy dispersive X‐ray spectroscopy (EDX) and scanning electron microscopy (SEM), which shows that the Pt particles have small size and big specific surface. Cyclic voltammetry (CV) research showed that the Pt nanoparticles had novel catalytic activity for methanol when the immersion deposition time was past 24 min.
Pervaporation Separation and Catalysis Activity of Novel Zirconium Silicalite‐1 Zeolite Membrane
Authors: Chen Pei , Chen Xinbing , Chen Xiangshu , An Zhongwei , Kita Hidetoshi
Published: September 2009

Novel zirconium silicalite‐1 zeolite membrane was hydrothermally prepared on the mullite porous support at 150–185°C for 40–72 h by an "in situ" method using tetraethyl orthosilicate (TEOS), zirconium butoxide (ZBOT) and tetrapropylammonium hydroxide (TPAOH) as silica source, zirconium source and organic structure directing agent, respectively. X‐ray diffraction (XRD) patterns, fourier transformed infrared (FT‐IR) spectra, and inductively coupled plasma‐atomic emission spectrometry (ICP) of the accompanying zeolite powder confirmed that the zirconium was isomorphously incorporated into the zeolite framework. The surface chemical compositions of the obtained membrane were measured with an energy‐dispersive X‐ray spectral analyzer (EDS), and the membrane morphologies were observed by a scanning electron microscope (SEM). The results showed that the zeolite crystals growing on the support were zirconium silicalite‐1 zeolites, and the dense membrane layer was composed of the well inter‐growing zeolite crystals. The zirconium silicalite‐1 zeolite membrane, which was derived from the synthesis solution having a molar ratio of 1.00SiO2:0.01ZrO2:0.17TPAOH:120H2O, showed high ethanol permselectivity with a flux of 1.01 kg/(m2·h) accompanied with a separation factor of 73 for ethanol/water (5/95, w/w) system under a pervaporation condition at 60°C. Moreover, this membrane displayed pervaporation‐aided catalysis activity for iso‐propanol oxidation with hydrogen peroxide as oxidant, and the corresponding iso‐propanol conversion was 35%.
Syntheses, Structure Analyses and Thermal Stabilities of Two Schiff Base Metal Complexes
Authors: Zhang Yinli , Chen Sanping , Fan Guang , Zhao Zhijie , Gao Shengli
Published: September 2009

A Schiff base ligand 1‐salicylideneamino‐1,3,4‐triazole (L) was prepared. Two new complexes with Schiff base, [Zn(L)2(SCN)2] (1) and [Co2(L)5(SCN)4]·H2O (2) have been synthesized and structurally characterized. Complex 1 takes a mononuclear zinc structure and the coordination geometry of zinc atom exhibits a distorted tetrahedron, in which a zig‐zag chain is constructed through hydrogen bonding interactions. A 2D supramolecular network is formed through Π‐Π stacking between triazole planes and phenyl planes of adjacent chains, and a 3D supramolecular network is further constructed by these non‐covalent Π‐Π stacking interactions between the triazole planes of neighboring layers. Complex 2 takes a dinuclear structure with the bidentate‐bridging Schiff base ligands, and cobalt site exhibits a distorted octahedron. The lattice water molecules and neutral complex 2 units form a dimer with hydrogen bonding interactions. In addition, IR and thermal gravimetric analysis are presented.
Microwave Assisted Efficient Synthesis and Crystal Structures of O‐Hexadecalkylated Pyrogallol[4]arenes
Authors: Chen Jiao , Chen Weifeng , Yan Chaoguo
Published: September 2009

Under microwave irradiation alkylation reactions of sixteen phenolic hydroxyl groups in tetra(p‐hydroxyphenyl)pyrogallol[4]arene with alkylating reagents such as n‐butyl iodide, benzyl chloride, and ethyl α‐chloroacetate were finished quickly in one step to give the fully O‐alkylated products. The X‐ray single crystal diffraction showed that the three peralkylated pyrogallol[4]arenes existed in rctt (cis‐trans‐trans) configuration.
Reactions of Cyclohexyl Isocyanide with η5‐Substituted Cyclo‐pentadienyl MoMo Triply Bonded Complexes. Crystal Structure of [Mo(CO)2(η5‐C5H4CO2CH3)]2(μ‐η2‐CNC6H11)
Authors: Li Qingshan , Luo Chuncheng , Song Licheng
Published: September 2009

Reactions of one or two equiv. of cyclohexyl isocyanide in THF at room temperature with MoMo triply bonded complexes [Mo(CO)2(η5‐C5H4R)]2 (R=COCH3, CO2CH3) gave the isocyanide coordinated MoMo singly bonded complexes with functionally substituted cyclopentadienyl ligands, [Mo(CO)2(η5‐C5H4R)]2(μ‐η2‐CNC6H11) (1a, R=COCH3; 1b, R=CO2CH3) and [Mo(CO)2(η5‐C5H4R)(CNC6H11)]2 (2a, R=COCH3; 2b, R=CO2CH3), respectively. Complexes 1a, 1b and 2a, 2b could be more conveniently prepared by thermal decarbonylation of MoMo singly bonded complexes [Mo(CO)3(η5‐C5H4R)]2 (R=COCH3, CO2CH3) in toluene at reflux, followed by treatment of the resulting MoMo triply bonded complexes [Mo(CO)2(η5‐C5H4R)]2 (R=COCH3, CO2CH3) in situ with cyclohexyl isocyanide. While 1a, 1b and 2a, 2b were characterized by elemental analysis and spectroscopy, 1b was further characterized by X‐ray crystallography.
DNA Binding and Cleavage Activity of Zinc(II) Complex of N,N′‐Bis(2‐guanidinoethyl)‐2,6‐pyridinedicarboxamide
Authors: Shao Ying , Ding Yong , Xu Weihong , Wei Li , Liu Fang , Lu Guoyuan
Published: September 2009

The interaction of zinc(II) complex of N,N′‐bis(guanidinoethyl)‐2,6‐pyridinedicarboxamide (Gua) with DNA was studied by CD spectroscopy and agarose gel electrophoresis analysis. The results indicate that the DNA binding affinity of Zn2+‐Gua is stronger than that of Gua and the Zn2+‐Gua can promote the cleavage of phosphodiester bond of supercoiled DNA under a physiological condition, which is ∼106 times higher than DNA natural degradation. The hydrolysis pathway was proposed as the possible mechanism for DNA cleavage promoted by the Zn2+‐ Gua. The acceleration is due to cooperative catalysis of the zinc cation center and the functional groups (bisguanidinium groups).
Stereoselective Synthesis of (Z)‐4‐(2‐Bromovinyl)benzene‐sulfonyl Azide and Its Synthetic Utility for the Transformation to (Z)‐N‐[4‐(2‐Bromovinyl)benzenesulfonyl]imidates
Authors: Zhang Wensheng , Kuang Chunxiang , Yang Qing
Published: September 2009

A novel method for the stereoselective synthesis of (Z)‐4‐(2‐bromovinyl)benzenesulfonyl azide by simultaneous azidation and debrominative decarboxylation of anti‐2,3‐dibromo‐3‐(4‐chlorosulfonylphenyl)propanoic acid using NaN3 only was developed. Facile transformation of (Z)‐4‐(2‐bromovinyl)benzenesulfonyl azide to (Z)‐N‐[4‐ (2‐bromovinyl)benzenesulfonyl]imidates was also achieved by Cu‐catalyzed three‐component coulping of (Z)‐4‐(2‐bromovinyl)benzenesulfonyl azide, terminal alkynes and alcohols/phenols.
Gas Phase Conversion of Carbon Tetrachloride to Alkyl Chlorides Catalyzed by Supported Ionic Liquids
Authors: Sun Aijun , Zhang Jinlong , Li Chunxi , Meng Hong
Published: September 2009

An efficient way of converting carbon tetrachloride (CTC) to alkyl chlorides is reported, which uses the catalysts of ionic liquids supported on granular active carbon. The catalytic performance was evaluated in a temperature range of 120–200°C and atmospheric pressure for different ionic liquids, namely 1‐butyl‐3‐methylimidazolium chloride, 1‐octyl‐3‐methylimidazolium chloride, hydrochloric salts of N‐methylimidazole (MIm), pyridine and triethylamine, as well as bisulfate and dihydric phosphate of N‐methylimidazole. On this basis, the reaction mechanism was proposed, and the influences of the reaction temperature and the attributes of ionic liquids were discussed. The overall reaction was assumed to be comprised of two steps, the hydrolysis of CTC and reaction of HCl with alcohols under acidic catalyst. The results indicate that the conversion of CTC increased monotonically with temperature and even approached 100% at 200°C, while the maximum selectivity to alkyl chlorides was obtained around 160°C. This reaction might be potentially applicable to the resource utilization of superfluous byproduct of CTC in the chloromethane industry.
Apo‐CopC and CopC‐Cu(II) Unfolding Characteristics in GuHCl Solution
Authors: Li Huiqing , Zhao Yaqin , Yang Binsheng
Published: September 2009

The stability of CopC, a copper resistant protein with a Greek β‐barrel motif, in GuHCl solution was investigated by fluorescence spectra. Parameter A, characterizing position and shape of the fluorescence spectra, "phase diagram" method of fluorescence, and cupric binding capacity in GuHCl solution of different concentration showed that the denaturation transition of apo‐CopC and CopC‐Cu(II) might be fitted to a simple two‐state model. According to a two‐state model, the free energy of stabilization for apo‐CopC and CopC‐Cu(II), (17.08±0.35) and (23.81±0.45) kJ·mol‐1 respectively, was obtained. Copper(II) increased the stability of apo‐CopC. The higher thermodynamics stability of CopC‐Cu(II) was revealed to originate in both the faster folding and the slower unfolding rates by unfolding kinetics.
Solid Substrate Room Temperature Phosphorimetry for the Determination of Trace Mercury Based on the Reaction between Alkaline Phosphatase and Mercury Using Triton X‐100 as a Sensitizer
Authors: Liu Jiaming , Li Feiming , Lin Shaoqin , Li Zhiming , Chen Yayu , Lin Huiqing , Huang Lichai , Cai Jingping , Chen Xuejuan
Published: September 2009

A new solid substrate room temperature phosphorimetry (SSRTP) for the determination of trace mercury has been established, using Triton X‐100 as a sensitizer. The regression equation of working curve was ΔIp=11.40m(Hg2+)+1.569 (ag·spot−1, n=6, ΔIp=Ip1−Ip2, Ip1 and Ip2 referred to the phosphorescence intensity of the blank reagent and the test solution, respectively), and correlation coefficient (r) was 0.9984. The RSD valus of the determination of 0.016 and 8.0 ag·spot−1 Hg2+ were 4.1% and 1.7% (n=8), respectively, indicating that the method had good repeatability. The limit of detection (LOD) calculated by 3Sb/k was 7.0 zg·spot−1 Hg2+ (corresponding concentration: 1.8×10−17 g·mL−1, Sb=0.025, n=11). This method has high sensitivity, selectivity and precision, which was applied to determination of trace mercury in water samples with the result being agreed very well with that of dithizone extraction spectrophotometry.
Uncatalyzed, One‐pot Synthesis of 3,3′‐(Benzylene)‐ bis(4‐hydroxy‐2H‐chromen‐2‐one) Derivatives under Thermal Solvent‐free Conditions
Authors: Shaterian Hamid Reza , Honarmand Moones
Published: September 2009

A series of 3,3′‐(benzylene)bis(4‐hydroxy‐2H‐chromen‐2‐one) derivatives have been synthesized from condensation reactions of 4‐hydroxycoumarin with benzaldehydes under thermal solvent‐free conditions. This environmentally friendly synthesis is uncatalyzed and affords the desired products in excellent yields.
A Novel Catalytic Method for the Oxidation of Sulfides to Sulfoxides with Silica Sulfuric Acid and Sodium Nitrite in the Presence of KBr and/or NaBr as Catalyst
Authors: Goudarziafshar Hamid , Ghorbani‐choghamarani Arash , Nikoorazm Mohsen , Naserifar Zahra
Published: September 2009

Highly efficient selective oxidation of sulfides to sulfoxides by NaNO2 and silica sulfuric acid catalyzed with KBr or NaBr has been reported. This oxidation was carried out in the presence of wet SiO2 (50% w/w) in acetonitrile at room temperature with good to excellent yields.
K2CO3‐Promoted Cascade Michael‐Alkylation Reactions: A Facile Preparation of Diethyl trans‐2,3‐Disubstituted 1,1‐Cyclopropanedicarboxylates
Authors: Yang Gaosheng , Hua Yuanyuan , Shen Yue
Published: September 2009

A cascade Michael‐alkylation reaction of diethyl benzylidenemalonates with chloroacetophenones was realized by using K2CO3 as the promoter. With this method, a series of diethyl trans‐2,3‐disubstituted 1,1‐cyclopropane‐ dicarboxylates have been facilely synthesized in moderate yields under mild conditions. The relative configurations of two typical products were confirmed by X‐ray crystallographic analysis.
Synthesis and Crystal Structures of Two Complexes [Mn2(L)2(H2bta)2(H2O)]n and [Cu2(L)(H2bta)0.5(H2O)]n
Authors: Liu Ruiping , Yang Xuwu , Wang Lijun , Liu Fei , Zhang Lingling , Yu Fushan , Chen Sanping
Published: September 2009

Two new complexes, [Mn2(L)2(H2bta)2(H2O)]n (1) and [Cu2(L)(H2bta)0.5(H2O)]n (2) (H4bta=1,2,4,5‐benzene‐tetracarboxylic acid, L=imidazo[4,5‐f][1,10]phenathroline) were prepared under hydrothermal conditions and their structures determined by single‐crystal X‐ray diffration. The X‐ray diffraction reveals that complex 1, consisting of two crystallographically independent fragments A1 and A2, displays an interesting 3D supramolecular network constructed with ABAB sequence through hydrogen bonding interactions. In complex 2, the copper atoms connected by the H2bta2− ligands, the chains also are assembled into a 3D honeycomb configuration network formed by moleculars and aromatic π‐π stacking interactions.
Application of 1‐(2‐Pyridylazo)‐2‐naphthol Anchored SiO2 Nanoparticles for the Preconcentration of Trace Pb2+ from Different Water and Food Samples
Authors: Kaur Anupreet , Gupta Usha
Published: September 2009

SiO2‐PAN nanoparticles has been synthesized by reacting silica nanoparticles with 3‐aminopropyltriethoxysilane, formaldehyde and 1‐(2‐pyridylazo)‐2‐naphthol and characterized by FT‐IR and SEM which were used as new sorbent for the preconcentration of trace amount of Pb2+ from various samples. Conditions of the analysis such as preconcentration factor, effect of pH, sample volume, shaking time, elution conditions and effects of interfering ions for the recovery of analyte were investigated. The adsorption capacity of the nanometer SiO2‐PAN was found to be 168.34 μmol/g at optimum pH and the detection limit (3δ) was 0.63 µg/L. The extractant showed rapid kinetic sorption. The adsorption equilibrium of Pb2+ on the nanometer SiO2‐PAN was achieved within 15 min. Adsorbed Pb2+ was easily eluted with 6 mL of 4 mol·L−1 hydrochloric acid. The maximum preconcentration factor was 50. The method was applied to determine trace amounts of Pb2+ in different samples (water and food samples).
A New Biindenylidenedione Compound with Two Azobenzene Units: Synthesis and Photochromic Behavior Both in Solution and in the Solid State
Authors: Liu Juyan , Han Jie , Wang Juanyu , Pang Meili , Meng Jiben
Published: September 2009

A new photochromic biindenylidenedione compound bearing two azobenzene units was synthesized and characterized by means of 1H NMR, 13C NMR, ESI‐MS and elemental analysis. The photochromic and photo‐induced radical properties were investigated by means of UV‐Vis and electron spin resonance spectroscopy, respectively. The results showed that the title compound exhibited photochromic behavior with good fatigue resistances both in solution and in the solid state.
Isolation and partial purification of the Saccharomyces cerevisiae cytokinetic apparatus
Authors: Young Brian A. , Buser Christopher , Drubin David G.
Published: September 2009

Cytokinesis is the process by which a cell physically divides in two at the conclusion of a cell cycle. In animal and fungal cells, this process is mediated by a conserved set of proteins including actin, type II myosin, IQGAP proteins, F‐BAR proteins, and the septins. To facilitate biochemical and ultrastructural analysis of cytokinesis, we have isolated and partially purified the Saccharomyces cerevisiae cytokinetic apparatus. The isolated apparatus contains all components of the actomyosin ring for which we tested—actin, myosin heavy and light chain, and IQGAP—as well as septins and the cytokinetic F‐BAR protein, Hof1p. We also present evidence indicating that the actomyosin rings associated with isolated cytokinetic apparati may be contractile in vitro, and show preliminary electron microscopic imaging of the cytokinetic apparatus. This first successful isolation of the cytokinetic apparatus from a genetically tractable organism promises to make possible a deeper understanding of cytokinesis. © 2009 Wiley‐Liss, Inc.
Synthesis, Biological Evaluation of 1,1‐Diarylethylenes as a Novel Class of Antimitotic Agents
Authors: Hamze Abdallah , Giraud Anne , Messaoudi Samir , Provot Olivier , Peyrat Jean‐François , Bignon Jérôme , Liu Jian‐Miao , Wdzieczak‐Bakala Joanna , Thoret Sylviane , Dubois Joëlle , Brion Jean‐Daniel , Alami Mouad
Published: September 2009

The cytotoxic activities of 23 new isocombretastatin A derivatives with modifications on the B‐ring were investigated. Several compounds exhibited excellent antiproliferative activity at nanomolar concentrations against a panel of human cancer cell lines. Compounds isoFCA‐4 (2 e), isoCA‐4 (2 k) and isoNH2CA‐4 (2 s) were the most cytotoxic, and strongly inhibited tubulin polymerization with IC50 values of 4, 2 and 1.5 μM, respectively. These derivatives were found to be 10‐fold more active than phenstatin and colchicine with respect to growth inhibition but displayed similar activities as tubulin polymerization inhibitors. In addition, cell cycle arrest in the G2/M phase and subsequent apoptosis was observed in three cancer cell lines when treated with these compounds. The disruptive effect of 2 e, 2 k and 2 s on the vessel‐like structures formed by human umbilical vein endothelial cells (HUVEC) suggest that these compounds may act as vascular disrupting agents. Both compounds 2 k and 2 s have the potential for further prodrug modification and development as vascular disrupting agents for treatment of solid tumors.
A rare case of paratesticular pleomorphic rhabdomyosarcoma diagnosed by fine needle aspiration: A case report
Authors: Kishore Bimal , Khare Pratima , Gupta Rashmi Jain , Gupta Chhaya , Khare Vandana
Published: September 2009

Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma of children and young adults. It represents 6.5% of all malignant tumors in pediatrics with an annual incidence of 4 to 7 cases per million children. Embryonal RMS arising in paratesticular region in young males is a common entity, however pleomorphic RMS in such location is quite rare. An eighteen year old male presented with painless right scrotal mass measuring 7× 6 × 5 cm of two year duration, which was reported on ultrasonography as extratesticular tumor. Fine needle aspiration showed cellular smears comprising of pleomorphic population of mostly singly scattered cells and few cell aggregates. Few isolated large cells with whip like cytoplasmic processes and faint cross‐striations were also seen. A diagnosis of paratesticular malignant mesenchymal tumor probably RMS was made. Tumor was removed surgically with right sided orchidectomy. On histopathology, it was reported as pleomorphic RMS. There was focal lymphatic invasion and involvement of rete testis. Immunostaining of tumor cells revealed myogenin and desmin positivity. The case is being presented because of diagnosis of RMS on Fine needle aspiration and rare occurrence of pleomorphic RMS in paratesticular location. Diagn. Cytopathol. 2010. © 2009 Wiley‐Liss, Inc.
Activity of nAChRs containing α9 subunits modulates synapse stabilization via bidirectional signaling programs
Authors: Murthy Vidya , Taranda Julián , Elgoyhen A. Belén , Vetter Douglas E.
Published: September 2009

Although the synaptogenic program for cholinergic synapses of the neuromuscular junction is well known, little is known of the identity or dynamic expression patterns of proteins involved in non‐neuromuscular nicotinic synapse development. We have previously demonstrated abnormal presynaptic terminal morphology following loss of nicotinic acetylcholine receptor (nAChR) α9 subunit expression in adult cochleae. However, the molecular mechanisms underlying these changes have remained obscure. To better understand synapse formation and the role of cholinergic activity in the synaptogenesis of the inner ear, we exploit the nAChR α9 subunit null mouse. In this mouse, functional acetylcholine (ACh) neurotransmission to the hair cells is completely silenced. Results demonstrate a premature, effusive innervation to the synaptic pole of the outer hair cells in α9 null mice coinciding with delayed expression of cell adhesion proteins during the period of effusive contact. Collapse of the ectopic innervation coincides with an age‐related hyperexpression pattern in the null mice. In addition, we document changes in expression of presynaptic vesicle recycling/trafficking machinery in the α9 null mice that suggests a bidirectional information flow between the target of the neural innervation (the hair cells) and the presynaptic terminal that is modified by hair cell nAChR activity. Loss of nAChR activity may alter transcriptional activity, as CREB binding protein expression is decreased coincident with the increased expression of N‐Cadherin in the adult α9 null mice. Finally, by using mice expressing the nondesensitizing α9 L9′T point mutant nAChR subunit, we show that increased nAChR activity drives synaptic hyperinnervation. © 2009 Wiley Periodicals, Inc. Develop Neurobiol, 2009
Experiences with integrated impact assessment – empirical evidence from a survey in three European member states
Authors: Achtnicht Martin , Rennings Klaus , Hertin Julia
Published: September 2009

The paper contributes to the discussion on the use of methods and quantification in regulatory impact assessment. We investigate whether there are differences between the three dimensions of sustainable development in terms of the methodical efforts to assess potential impacts. Based on a survey in Germany, the Netherlands and the UK, we provide some evidence regarding these questions. We find that regulatory impact assessment is still biased towards assessing intended and mainly economic costs. There is a gap between the recommended use of methods in official guidance documents and the practice in member states. The reason for this gap can be seen in the existence of operational problems in practice such as lack of data or lack of tools. However, we find that the degree of sophistication of conducted IAs can be improved if responsible desk officers receive training or make use of guidance documents and receive support from co‐ordination units. Copyright © 2009 John Wiley & Sons, Ltd and ERP Environment.
Can attitudes predict outcomes? Public opinion, democratic institutions and environmental policy
Authors: Shum Robert Y.
Published: September 2009

The ‘post‐materialist’ value hypothesis, positing heightened concern for the environment, should predict eventual convergence in environmental policies. In the meantime, surprisingly wide variations persist, even when controlling for income levels. Is there a role for public opinion to explain better the divergences and outcomes observed in environmental policies? This paper explores a possible mechanism by which widely hypothesized income effects on policy can occur via pressure from public opinion. By building upon a median‐voter model of environmental policy‐making and developing an extension to include voter‐information characteristics, we test these effects on air pollution outcomes of varying (global, regional and local) scales. The results provide evidence of significant effects, but suggest two antecedent conditions necessary for political and opinion variables to have an effect: redistributive opportunities, and credible frameworks for addressing collective action problems. The implication is that relying on democratic reform alone may not suffice to improve environmental performance if underlying collective action problems are not addressed. Copyright © 2009 John Wiley & Sons, Ltd and ERP Environment.
The Structures of Lipopolysaccharides from Plant‐Associated Gram‐Negative Bacteria
Authors: Molinaro Antonio , Newman Mari‐Anne , Lanzetta Rosa , Parrilli Michelangelo
Published: September 2009

Gram‐negative bacterial lipopolysaccharides (LPSs) have multiple roles in plant–microbe interactions. LPSs contribute to the low permeabilities of bacterial outer membranes, which act as barriers to protect bacteria from plant‐derived antimicrobial substances. Conversely, perception of LPSs by plant cells can lead to the triggering of defence responses or to the priming of the plant to respond more rapidly and/or to a greater degree to subsequent pathogen challenge. LPSs are thus key molecules in the interactions between bacteria and plants, either in symbiosis or pathogenesis. Since LPSs are glycoconjugates genetically and chemically consisting of three different molecular regions, their detailed structure elucidation is a very topical and major scientific task for chemists, and is achieved by a combination of state‐of‐art chemical and spectroscopic techniques. Knowledge of LPSs' chemical structures is an important prerequisite for any further understanding of the biological processes in plant–microbe interactions. Moreover, the LPSs from Gram‐negative bacteria – especially those originating from plant‐associated bacteria – are a great source of novel monosaccharides with unusual and occasionally astounding chemical structures, never found in the eukaryotic world. This review presents the structures of LPSs from plant‐associated bacteria isolated and identified from 2001 onwards. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Application of the Bismuth Film Electrode for Voltammetric Determination of Titanium Using Ti(IV)‐Oxalate‐Chlorate Catalytic System
Authors: Bobrowski Andrzej , Królicka Agnieszka , Pacan Karolina , Zarębski Jerzy
Published: September 2009

The catalytic voltammetric protocol for the determination of titanium at a bismuth film electrode is presented. The method is based on the reduction of the Ti(IV)‐oxalate complex to Ti(III)‐oxalate in an acidic solution. It was proven that the addition of KClO3 causes rapid oxidation of Ti(III)‐oxalate and, subsequently, an increase of the reduction peak current of Ti(IV) at the bismuth film electrode. Parameters that influence the Ti response, including the film preparation, solution pH, oxalate acid and chlorate concentrations, were optimized. The exploitation of the bismuth film electrode under the optimized conditions yielded a stable response for titanium, with high sensitivity (12.5 μA μM−1), good precision (RSD=5.0%) and a low detection limit (1×10−8 M).
Room Temperature Ionic Liquids (RTILs) and Multiwalled Carbon Nanotubes (MWCNTs) as Modifiers for Improvement of Carbon Paste Ion Selective Electrode Response; A Comparison Study with PVC Membrane
Authors: Ganjali Mohammad Reza , Khoshsafar Hamid , Faridbod Farnoush , Shirzadmehr Ali , Javanbakht Mehran , Norouzi Parviz
Published: September 2009

Room temperature ionic liquids (RTILs), 1‐n‐butyl‐3‐methylimidazolium tetrafluoroborate, [bmim]BF4, and multiwalled carbon nanotubes (MWCNTs) were used for improvement of a praseodymium carbon paste ion selective sensor response. [bmim]BF4 can be a better binder than mineral oils. MWCNTs have a good conductivity which helps the transduction of the signal in carbon paste electrode. The characteristics of these electrodes as potentiometric sensors were evaluated and compared with PVC membrane sensor. The results indicate that potentiometric sensor constructed with ionic liquid shows an increase in performance in terms of Nernstian slope, selectivity, response time, and response stability compared to Pr(III) PVC membrane sensor.
Biofuel Cells with Switchable Power Output
Authors: Katz Evgeny
Published: September 2009

Biofuel cells with a switchable power output controlled by external physical or chemical signals were developed. The switchable properties of biofuel cells were achieved by modification of biocatalytic electrodes with signal‐responsive materials sensitive to various stimuli triggering reversible transition of the electrode interfaces between electrochemically active and inactive states. Electrical, magnetic and biochemical signals were used as stimuli controlling the electrode activity. Biochemical systems of various complexity mimicking Boolean logic operations AND/OR as well as multienzyme/multilogic gates networks were functionally coupled with the pH‐sensitive electrodes in the biofuel cell. This allowed switching ON and OFF the power production in the biofuel cell upon application of many different biochemical signals logically processed by the enzyme systems according to the built‐in logic ‘program’. The studied switchable biofuel cells controlled by electric, magnetic and biochemical signals exemplify novel bioelectronic devices activated by external signals on‐demand. They open a new facet in the multidisciplinary field of bioelectronics and keep a big promise for practical applications, particularly as implantable sustainable energy sources for biomedical applications. The present paper gives a short overview of various switchable/tunable biofuel cells with the power production controlled by external signals.
Absorbance‐Based Spectroelectrochemical Sensor for [Re(dmpe)3]+ (dmpe=dimethylphosphinoethane)
Authors: Morris Laura K. , Seliskar Carl J. , Heineman William R. , Del Negro Andrew S. , Bryan Samuel A.
Published: September 2009

A spectroelectrochemical sensor was developed for [Re(dmpe)3]+ as a nonradioactive analog for [Tc(dmpe)3]+. The sensor consists of an optically transparent electrode (OTE) coated with a thin film of sulfonated polystyrene‐block‐poly(ethylene‐ran‐butylene)‐block‐polystyrene (SSEBS). Colorless [Re(dmpe)3]+ was reversibly oxidized to [Re(dmpe)3]2+ (λmax=530 nm). [Re(dmpe)3]+ preconcentrated by ion‐exchange into the SSEBS film, resulting in a 20‐fold increase in peak current compared to a bare OTE after 1 h of exposure to aqueous [Re(dmpe)3]+ solution. Detection of [Re(dmpe)3]+ at concentrations down to 2×10−6 M was accomplished by electrochemical modulation of the complex and monitoring absorbance by attenuated total reflectance (ATR).