bluuebunny/crossref_metadata_2025 huggingface dataset:
Qualidade de vida de pacientes com câncer colorretal em terapia adjuvante
Authors: Nicolussi Adriana Cristina , Sawada Namie Okino
Published: June 2009

OBJETIVO: Avaliar a qualidade de vida, identificar os domínios afetados nos pacientes com câncer colorretal, caracterizar os dados sócio-demográficos, clínicos e terapêuticos e correlacioná-los aos domínios da qualidade de vida. MÉTODOS: Estudo transversal, realizado no Centro Especializado de Oncologia de Ribeirão Preto com 22 pacientes com câncer colorretal em terapia adjuvante, entre julho/ 2006 a setembro/ 2007. Utilizou-se o instrumento Quality of Life Core-30-Questionnaire. RESULTADOS: A qualidade de vida foi considerada satisfatória (média = 79,13). Os domínios mais afetados foram: Função Emocional e sintomas dor, insônia, fadiga. Nas correlações, as mulheres destacaram-se negativamente, apresentando piores escores nas Funções Emocional, Cognitiva e sintomas: dor, insônia, fadiga, constipação e perda de apetite. Os pacientes em radioterapia relataram mais dor e os assintomáticos à quimioterapia são os que obtiveram melhor qualidade de vida geral. CONCLUSÃO: A qualidade de vida foi satisfatória, relativamente pior nas mulheres, em radioterapia e que apresentaram efeitos colaterais da quimioterapia.
Extrato aquoso de fumo em corda no controle do carrapato de bovinos
Authors: Olivo Clair Jorge , Heimerdinger Arli , Ziech Magnos Fernando , Agnolin Carlos Alberto , Meinerz Gilmar Roberto , Both Francisco , Charão Pablo Santini
Published: June 2009

Este estudo teve por objetivo avaliar a eficiência de várias formulações feitas com fumo em corda no controle do carrapato (Boophilus microplus) de bovinos leiteiros da raça Holandesa naturalmente infestados. Os tratamentos foram constituídos por Amitraz a 0,025%; extrato aquoso de fumo em corda (EFC) a 1,25% + detergente neutro a 0,5% (em três aspersões, com intervalos de 24 horas entre elas); EFC a 1,25% + cal extinta a 1,25% (três aspersões); EFC a 5,0% + cal extinta a 2,0%, (três aspersões); EFC a 3,75% + detergente neutro a 0,5% (uma aspersão), e pelo grupo controle. Para a avaliação, foram observadas fêmeas ingurgitadas do carrapato, com comprimento superior a 4,0mm, antes da aplicação e no 1°, 2°, 3°, 4°, 5°, 6°, 7° e 14° dias após a aplicação de cada tratamento. A eficácia média de controle do carrapato no 14° dia foi de 100,0; 77,5; 22,0; 63,80; 25,3 e 0,0%, respectivamente. Verificou-se diferença significativa (P<0,05) entre os tratamentos constituídos pelo produto químico e por diferentes formulações de fumo em corda.
Sustentabilidade de sistemas de rotação e sucessão de culturas em solos de várzea no Sul do Brasil
Authors: Vernetti Junior Francisco de Jesus , Gomes Algenor da Silva , Schuch Luis Osmar Braga
Published: June 2009

A avaliação quantitativa com diferentes tipos de indicadores é fundamental na determinação da sustentabilidade dos sistemas de rotação e sucessão de culturas. Este estudo teve como objetivo avaliar a sustentabilidade de algumas sucessões de culturas em solo de várzea, nos sistemas de plantio direto (PD) e convencional (SC). O trabalho foi conduzido em Pelotas, Rio Grande do Sul (RS), em área experimental da Embrapa Clima Temperado. Os tratamentos foram constituídos por cinco anos de implantação de sistemas de rotação e sucessão de culturas de inverno e de primavera-verão, seguidos de dois anos de pousio e três anos da cultura do arroz irrigado. As culturas de primavera-verão foram o milho e a soja, além do arroz; enquanto que as de inverno foram gramíneas, leguminosas, consórcios, nabo forrageiro e campo natural. O delineamento experimental foi o de blocos ao acaso com parcelas subdivididas, com três repetições. As culturas de verão ocuparam as parcelas, enquanto as espécies de inverno foram alocadas nas subparcelas. Os parâmetros observados foram transformados em índices para padronizar as diversas variáveis, cada uma em relação àquela de melhor comportamento mensurado, e dispostos em quatro categorias de análise: (a) indicadores agronômicos (matéria seca e rendimento de grãos); (b) indicadores ambientais (fertilidade do solo); (c) indicadores energéticos (produção e eficiência energética); d) indicadores econômicos (valor bruto da produção e rentabilidade). Pela média harmônica obtida entre os índices dos indicadores, foram comparados os diferentes sistemas de rotação e sucessão de culturas, inferindo-se daí sua sustentabilidade e suas diferenças (Teste t P≤0,05). Concluiu-se que: (a) todos os sistemas de rotação e sucessão de culturas dos quais o milho faz parte apresentam maior índice de sustentabilidade; (b) os sistemas de rotação e sucessão de culturas S1 [gramínea x soja x arroz (PD)] e S4 [nabo x soja x arroz (PD)] apresentam, respectivamente, a maior e a menor sustentabilidade entre aqueles sistemas em que a cultura da soja participa; (c) o sistema S5 [campo nativo x soja x arroz (SC)] apresenta o menor índice de sustentabilidade; (d) o sistema S8 [Consórcio x milho x arroz (PD)] apresenta a melhor distribuição e o melhor equilíbrio entre as diversas perspectivas de sustentabilidade consideradas; (e) o sistema S10 [campo nativo x milho x arroz (SC)] tem pior desempenho, no que se refere à sustentabilidade entre os que incluem o milho; (f) o sistema de PD confere maior sustentabilidade às sucessões de cultura.
O uso da associação azitromicina e N-metil glucamina no tratamento da leishmaniose cutânea causada por Leishmania (Leishmania) amazonensis em camundongos C57BL6
Authors: Sampaio Raimunda Nonata Ribeiro , Lucas Íris Campos , Costa Filho Arnoldo Velloso da
Published: June 2009

FUNDAMENTOS: O tratamento de primeira escolha da leishmaniose tegumentar americana é a N-metil-glucamina que tem alta toxicidade, exige administração parenteral e nem sempre cura. A azitromicina mostrou ação in vitro e resultado contraditório na doença humana. OBJETIVO: Verificar se a associação N-metil-glucamina+azitromicina é mais eficaz do que N-metil-glucamina no tratamento da leishmaniose experimental. MÉTODOS: 25 camundongos inoculados com a cepa C57BL/6 de L. (L.) amazonensis foram divididos em dois grupos. Um foi tratado com 400mgSbV/kg/dia de N-metil-glucamina associado a 200mg/kg/dia de azitromicina durante 20 dias, e o outro com N-metil-glucamina, na mesma dose, durante o mesmo tempo. Foi feita avaliação clínica e parasitológica com análise estatística. RESULTADO: Na avaliação clínica, pesquisa de amastigotas e das culturas, não houve diferença estatística. Verificou-se, entretanto, diferença significante no resultado das culturas realizadas através de diluição limitante, que desfavoreceu a associação NMG+ azitromicina. CONCLUSÃO: A associação N-metil-glucamina e azitromicina não demonstrou mais eficácia do que o N-metil-glucamina em uso isolado.
Como o clipping pode auxiliar o dermatologista
Authors: Fillus Neto José , Tchornobay Ana Maria
Published: June 2009

Alterações ungueais são queixas muito frequentes nos consultórios dermatológicos. Onicomicoses representam cerca de 50% das onicopatias, daí a importância de se estabelecer o diagnóstico correto antes de se iniciar o tratamento. Neste artigo, relataremos a utilidade de um exame que é de fácil execução pelo clínico, de baixo custo e sensível: esse exame consiste na análise histopatológica da queratina ungueal distal, atualmente já consagrado com o termo clipping.
O processo de inclusão de crianças com deficiência auditiva na escola regular: vivências de professores
Authors: Rios Noemi Vieira de Freitas , Novaes Beatriz Cavalcanti de A. Caiuby
Published: June 2009

O objetivo do presente estudo foi descrever e discutir, a partir da vivência de professores, o processo de inclusão de crianças com deficiência auditiva em escola regular. Foram selecionadas três crianças entre 05 e 08 anos de idade, e seus respectivos professores. Por meio de entrevistas com as professoras das crianças, foi selecionado o material que permitiu caracterizar o processo de inclusão de cada criança do estudo. Os relatos das professoras sobre suas experiências com as crianças deficientes auditivas deste estudo parecem indicar que, ainda hoje, apesar da evolução das práticas inclusivas, prevalecem nas escolas muito mais os pressupostos da integração do que da inclusão. As professoras foram unânimes em admitir que não vêm sendo suficientemente preparadas para receber deficientes auditivos e pouco sabem sobre o desenvolvimento da audição, da linguagem e sobre como esses aspectos influenciam e determinam formas particulares de apreensão de conteúdos. Prevalece a idéia de que é a criança com necessidades educacionais especiais quem deve se adaptar ao ambiente, empenhar-se para ser nele integrada; ou então, as professoras buscam estratégias individuais de aproximação, sem que essa questão seja problematizada junto ao corpo técnico da escola, que ainda não vem efetivando transformações em sua organização para receber esses alunos.
A visão de escolares sobre drogas no uso de um jogo educativo
Authors: Rebello Sandra , Monteiro Simone , Vargas Eliane P.
Published: June 2009

Este estudo enfatiza a relevância da mediação cultural no uso de tecnologias educacionais. Para tal, descreve a percepção de 62 escolares da rede pública do Rio de Janeiro sobre temas abordados no Jogo da Onda, um jogo sobre o uso de drogas, e o interesse do grupo pelo material. A partir de grupos focais, observação das partidas e questionários, foi observado que a iniciação ao uso de drogas está relacionada à: pressão social de grupo, fácil acesso às drogas e ao não reconhecimento de que o consumo pessoal, mesmo descontínuo, pode levar à dependência química. Dissonâncias entre a visão dos escolares e o discurso preventivo repressivo e/ou técnico informativo sugere que as ações educativas devem privilegiar formas de apreensão das informações transmitidas, focando a interatividade, a interlocução, a informação e a reflexão.
Medicina, educação e psiquiatria para a infância: o Pavilhão-Escola Bourneville no início do século XX
Authors: Silva Renata Prudencio da
Published: June 2009

Este trabalho analisa a criação do Pavilhão-Escola Bourneville do Hospício Nacional de Alienados no início do século XX, primeira instituição brasileira para a assistência a crianças anormais. Destaca o conhecimento então produzido sobre os diagnósticos relativos à infância e sobre o método médico-pedagógico empregado no Pavilhão. Busca-se assim perceber as vias pelas quais a criança se constituiu em objeto da ciência psiquiátrica e das políticas públicas a ela relacionada naquele período.
Ventricular function in Chagas' heart disease
Authors: Maciel Benedito Carlos , Almeida Filho Oswaldo César de , Schmidt André , Marin-Neto José Antonio
Published: June 2009

Invasive and noninvasive methods used to evaluate ventricular function in Chagas's disease are reviewed. The traditional indices of overall ventricular performance reflect interaction of preload, contractility, afterload and heart rate. Therefore, they are unable to distinguish changes in contractility from modifications of loading conditions. The role of ventricular function as a predictor of mortality in chronic Chagas' heart disease is discussed. Ventricular function abnormalities in patients with indeterminate and digestive forms of Chagas' disease are especially emphasized. Finally, the evidence of early impairment of diastolic performance in patients with Chagas' disease is presented.
Explorando conteúdos matemáticos a partir de temas ambientais
Authors: Leite Maria Beatriz Ferreira , Ferreira Denise Helena Lombardo , Scrich Cintia Rigão
Published: June 2009

A Educação Ambiental constitui um processo educativo, cuja finalidade é desenvolver instrumentos pedagógicos e ampliar a prática educativa para que o homem viva em harmonia com o meio ambiente. A Modelagem Matemática é uma estratégia de ensino e aprendizagem, na qual os alunos transformam situações da realidade em modelos matemáticos por meio da investigação, ação e validação, abordando problemas que estão relacionados ao cotidiano. A Modelagem possibilita a aprendizagem de conteúdos matemáticos aplicados em outras ciências, onde a Matemática é aprendida e entendida como um instrumento para a compreensão e possível modificação da realidade. Assim, os modelos matemáticos podem constituir uma ferramenta útil na conscientização do indivíduo enquanto sujeito da sua própria ação. Neste trabalho os temas abordados são: crescimento de peixes, poluição do ar e agrotóxicos.
Remobilization of Polychlorinated Biphenyl from Baltic Sea Sediment: Comparing the Roles of Bioturbation and Physical Resuspension
Authors: Hedman Jenny E. , Tocca Julia Stempa , Gunnarsson Jonas S.
Published: June 2009

The release of a 14C-labeled trichlorobiphenyl compound ([14C]PCB 32) from sediment to water was quantified weekly in a 30-d microcosm experiment with recirculating water. Two modes of bioturbation-driven polychlorinated biphenyl (PCB) release—bioturbation by the amphipod Monoporeia affinis (a particle biodiffuser) and bioturbation by the polychaete Marenzelleria sp. (a bioirrigator)—were compared to the PCB release caused by physical resuspension of the sediment generated by a motor-driven paddle used twice a week. Bioturbation by the amphipod M. affinis caused a significantly higher remobilization of both particle-associated PCB (PCBpart) and dissolved PCB (PCBdiss) than the other treatments. Bioturbation by Marenzelleria sp. and physical resuspension caused a similar release of PCBdiss despite a significantly higher amount of total suspended solids in the water column after physical resuspension. In all treatments, the release of PCBdiss was more than one order of magnitude higher than that of PCBpart, indicating a significant potential route of exposure for pelagic organisms, such as fish, to the most bioavailable PCB form. Calculated mass-transfer coefficients (0.3–1.3 cm/d) correspond to previously reported values for trichlorinated PCBs. The present results indicate that biological reworking of sediments can be just as, or even more, important than physical resuspension for the remobilization of sediment-bound contaminants.
Statistical assessment for spatio-temporal water quality in Angkor, Cambodia
Authors: Ki Seo Jin , Kang Joo-Hyon , Lee Young Geun , Lee Yun Seok , Sthiannopkao Suthipong , Kim Joon Ha
Published: June 2009

Comprehensive water quality monitoring was conducted to assess the water quality conditions and to determine the impact of urban infrastructure on ambient water quality in Angkor, Cambodia. During this study, surface water, groundwater, and sediment samples were collected for two distinctive seasons in 2006–2007 at 58 monitoring sites along and near the Siem Reap River, in Tole Sap Lake (TSL), and West Baray, the primary water resources in this region. To assess the seasonal and spatial variability of 27 water quality parameters, multivariate analysis of variance, hierarchical cluster analysis, and the Kruskal-Wallis test were conducted using the obtained data. Differences and relationships between the surface water and groundwater were also investigated using t-test and correlation analysis, respectively. The results of these tests showed that the bacterial indicators need special attention as the urban infrastructure of the downtown area caused increased levels of these bacterial indicators in both surface water and groundwater. However, for most parameters, though surface water showed strong seasonal variations, groundwater presented relatively stable conditions between seasons (p>0.05) with site-specific geochemical conditions. Sediment quality illustrated that pollution levels of 10 trace metals were the highest in TSL because of its unique characteristic (river with backward flow), but did not reflect any potential enrichment from urban development. Overall, the results reveal that while the urban infrastructure in this region has not significantly affected most of the water quality parameters, bacteria and coliphages are still a main concern due to their contributions in widespread waterborne diseases. Thus, careful mitigation plans for reducing each pollutant source are needed in the Angkor area.
Enhanced bio-energy recovery in a two-stage hydrogen/methane fermentation process
Authors: Lee M. J. , Song J. H. , Hwang S. J.
Published: June 2009

A two-stage hydrogen/methane fermentation process has emerged as a feasible engineering system to recover bio-energy from wastewater. Hydrogen-producing bacteria (HPB) generate hydrogen from readily available carbohydrates, and organic acids produced during the hydrogen fermentation step can be degraded to generate methane in the following step. Three strong acids, HCl, H2SO4, and HNO3, were tested to determine the appropriate pre-treatment method for enhanced hydrogen production. The hydrogen production rates of 230, 290, and 20 L/kg-glucose/day was observed for the sludge treated with HCl, H2SO4, and HNO3, respectively, indicating that the acid pre-treatment using either HCl or H2SO4 resulted in a significant increase in hydrogen production. The fluorescent in situ hybridization method indicated that the acid pre-treatment selectively enriched HPB including Clostridium sp. of cluster I from inoculum sludge. After hydrogen fermentation was terminated, the sludge was introduced to a methane fermentation reactor. This experiment showed methane production rates of 100, 30, and 13 L/kg-glucose/day for the sludge pre-treated with HCl, H2SO4, and HNO3, respectively, implying that both sulfate and nitrate inhibited the activity of methane-producing bacteria. Consequently, the acid pre-treatment might be a feasible option to enhance biogas recovery in the two-stage fermentation process, and HCl was selected as the optimal strong acid for the enrichment of HPB and the continuous production of methane.
Reduction of nitrate by resin-supported nanoscale zero-valent iron
Authors: Park Heesu , Park Yong-Min , Yoo Kyoung-Min , Lee Sang-Hyup
Published: June 2009

For environmental remediation of a contaminated groundwater, the use of nanosized zero-valent iron (nZVI) represents one of the latest innovative technologies. However, nZVI gets easily agglomerated due to its colloidal characteristics and has limited applications. To overcome this drawback, nZVI was immobilized on a supporting material. In this study, nZVI was formed and bound to ion-exchange resin spheres at the same time through the borohydride reduction of an iron salt. The pore structures and physical characteristics of the supported nZVI were investigated and its reactivity was measured using nitrate. The degradation of nitrate appeared to be a pseudo first-order reaction with the observed reaction rate constant of 0.425 h−1 without pH control. The reduction process continued but at a much lower rate with a rate constant of 0.044 h−1. When the simulated groundwater was used to assess the effects of coexisting ions, the rate constant was 0.078 h−1 and it also reduced to 0.0021 h−1 in later phase. The major limitation of ZVI use for nitrate reduction is ammonium production. By using a support material with ion-exchange capacity, this problem can be solved. The ammonium was not detected in our batch tests.
Tryptophanase-Catalyzed L-Tryptophan Synthesis from D-Serine in the Presence of Diammonium Hydrogen Phosphate
Authors: Shimada Akihiko , Ozaki Haruka , Saito Takeshi , Noriko Fujii
Published: June 2009

Tryptophanase, an enzyme with extreme absolute stereospecificity for optically active stereoisomers, catalyzes the synthesis of L-tryptophan from L-serine and indole through a β-substitution mechanism of the ping-pong type, and has no activity on D-serine. We previously reported that tryptophanase changed its stereospecificity to degrade D-tryptophan in highly concentrated diammonium hydrogen phosphate, (NH4)2HPO4 solution. The present study provided the same stereospecific change seen in the D-tryptophan degradation reaction also occurs in tryptophan synthesis from D-serine. Tryptophanase became active to D-serine to synthesize L-tryptophan in the presence of diammonium hydrogen phosphate. This reaction has never been reported before. D-serine seems to undergo β-replacement via an enzyme-bonded α-aminoacylate intermediate to yield L-tryptophan.
Minimally invasive plate osteosynthesis: Applications and techniques in dogs and cats
Authors: Hudson C.C. , Lewis D.D. , Pozzi A.
Published: June 2009

Bone plating has been used as a method of fracture management for many years. Recently, a trend toward the use of fracture fixation techniques which preserve the local fracture environment, known as biological osteosynthesis, has evolved. This trend has resulted in the development of a less traumatic method of bone plating referred to as minimally invasive plate osteosynthesis (MIPO), or percutaneous plating. During MIPO fracture stabilisation, plates are inserted through short incisions and a communicating epiperiosteal tunnel. Typically, bone plates applied in this fashion have a bridging function. Promising outcomes have been reported in human patients undergoing MIPO fracture stabilisation, and limited reports of the use of this technique in dogs and cats have yielded positive results as well. Careful case selection, pre-operative planning, and appropriate instrumentation are necessary when performing the technique. Rapid time to union, low complication rates and good return to function have been noted in human patients. Additional research is needed to define selection criteria and outline the definitive benefits of MIPO in dogs and cats.
Germanium(II) Dications Stabilized by Azamacrocycles and Crown Ethers
Authors: Cheng Fei , Hector Andrew L. , Levason William , Reid Gillian , Webster Michael , Zhang Wenjian
Published: June 2009

Eine Krone für Germanium: Neutrale Aza‐ und Oxamakrocyclen stabilisieren halogenfreie Germanium(II)‐Dikationen (siehe Bild: Ge türkis, N blau, C grau). Die resultierenden Strukturen hängen stark von der Zahl und Art der Donoratome und von der Größe des Makrocyclus ab.

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[Al4(OH)2(OCH3)4(H2N‐bdc)3]⋅x H2O: A 12‐Connected Porous Metal–Organic Framework with an Unprecedented Aluminum‐Containing Brick
Authors: Ahnfeldt Tim , Guillou Nathalie , Gunzelmann Daniel , Margiolaki Irene , Loiseau Thierry , Férey Gérard , Senker Jürgen , Stock Norbert
Published: June 2009

Al together now! A new stable aluminum aminoterephthalate system contains octameric building blocks that are connected by organic linkers to form a 12‐connected net (see picture). The structure adopts a cubic centered packing motive in which octameric units replace individual atoms, thus forming distorted octahedral (red sphere) and tetrahedral cages (green spheres) with effective accessible diameters of 1 and 0.45 nm, respectively.

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Distributed leader‐follower flocking control
Authors: Wang Zongyao , Gu Dongbing
Published: June 2009

This paper presents a fuzzy based leader‐follower flocking system. To maintain the distance between robots, we use a fuzzy logic controller to design a “force function” which is related to the relative distance between neighbours. The “force function” is used to control velocity of robots. To prove stability of the flocking system, we build a Hamilton function which is kinetic energy of the flocking system. Utilizing the LaSalle's invariance principle, we prove that the system is stable. Specially, we develop a flocking controller in local form. By using the local controller, the robots in the flocking system only need to know local information (relative distances and relative angles between neighbours). To evaluate performance of the flocking system, we simulate the flocking system tracking trajectories with different shapes. The local flocking algorithm is tested with three Pioneer robots. We use the SICK laser scanner to measure the relative distances and relative angles between neighbours. Copyright © 2009 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Design of nonlinear H∞ controllers using describing functions with application to servomechanism
Authors: Nassirharand Amir , Firdeh S. R. Mousavai
Published: June 2009

A systematic procedure for design of nonlinear H∞ controllers for amplitude‐dependent nonlinear plants is presented. The procedure is based on describing function concepts involving sinusoidal input describing function models of the nonlinear plant followed by application of an inverse describing function technique to arrive at nonlinear gains of the H∞ controller. The procedure is applied to a servomechanism problem to demonstrate the typical results that may be achieved. Copyright © 2009 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Output feedback stabilization for delayed large‐scale stochastic systems with markovian jumping parameters
Authors: Zhang Baoyong , Xu Shengyuan , Zou Yun
Published: June 2009

This paper deals with the problem of decentralized output feedback stabilization for a class of large‐scale stochastic time‐delay systems with Markovian jumping parameters. Attention is focused on the design of a decentralized dynamic output feedback controller, which is also with Markovian jumping parameters, such that the closed‐loop system is exponentially mean‐square stable. A sufficient condition for the solvability of this problem is proposed in terms of linear matrix inequalities. Copyright © 2009 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Does identification predict community involvement? Exploring consequences of social identification among the Jewish minority in Poland
Authors: Bilewicz Michał , Wójcik Adrian
Published: June 2009

Previous research indicated that people who strongly identify with their own group are more involved in the group's actions. The current study examines the relation between three dimensions of group identification (affect, ties, centrality) and forms of community involvement among members of the Jewish minority in Poland. The strength of ingroup ties predicted involvement in the ethnic minority community. The link between identification and involvement was mediated by the cultural dominance. The reported study was the first quantitative survey of the Jewish community in post‐War Poland. Copyright © 2009 John Wiley & Sons, Ltd.
Polyamine Receptors Containing Dipyridine or Phenanthroline Units: Clues for the Design of Fluorescent Chemosensors for Metal Ions
Authors: Bazzicalupi Carla , Bencini Andrea , Biagini Silvia , Bianchi Antonio , Faggi Enrico , Giorgi Claudia , Marchetta Melania , Totti Federico , Valtancoli Barbara
Published: June 2009

The synthesis of the macrocyclic receptor L1, which contains a tetraamine chain linking the 6,6′‐positions of a 2,2′‐dipyridine moiety, is reported. Its basicity properties and complexation features toward CuII, ZnII, CdII and PbII have been studied in aqueous solutions by means of potentiometric, UV/Vis spectroscopy and fluorescence emission measurements and compared with those of ligand L2, in which a 1,10‐phenanthroline moiety replaces the dipyridine unit of L1. In metal coordination, L1 shows a marked selectivity toward CdII over ZnII and PbII. The crystal structures of its metal complexes shows that L1 possesses a preferential tetradentate binding site for metal cations, composed of the dipyridine unit and the two adjacent benzylic amine groups. This binding site has the proper dimension and conformation to selectively coordinate the CdII ion, as confirmed by DFT calculations carried out on the complexes. This coordinative zone is lost in L2. The rigidity of phenanthroline does not allow the simultaneous binding of both the benzylic amine groups to ZnII and CdII and, in fact, one benzylic amine is not coordinated to these metal cations. The fluorescence emission properties of the L1 and L2 complexes are strongly pH dependent. Only the ZnII and CdII complexes with L1 display fluorescence emission at neutral pH. This feature is related to the formation in solution at pH 7 of emissive protonated complexes of the type [M(HxL)](2+x)+ (x=1–3), in which all the nitrogen donors are involved in metal or proton binding. The emissive characteristics of these protonated complexes are confirmed by the fluorescence emission spectra collected on the [Zn(HL1)Br][ClO4]2 and [Cd(HL1)Br][ClO4]2 solid compounds dissolved in CH3CN. Conversely, the ZnII and CdII complexes with L2 are not emissive; in fact, they contain a benzylic amine group not involved in metal or proton binding that can quench the fluorescence emission of the fluorophore, thanks to a photoinduced electron‐transfer process.
Highly Enantioselective Epoxidation of cis‐Alkenylsilanes
Authors: Matsumoto Kazuhiro , Kubo Takuya , Katsuki Tsutomu
Published: June 2009

A general and highly enantioselective method for the epoxidation of cis‐alkenylsilanes, in which the epoxysilanes were obtained with complete enantioselectivity in the presence of 0.5–2 mol % of a Ti–Salalen complex. The combination of this epoxidation method and the following transformations is a powerful approach that provides synthetically important epoxides, such as styrene oxides and geminally disubstituted epoxides, in enantiopure form.

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Mit Stradivari, Kunstsaiten und Kolophonium. Das chemische Geheimnis der Geigenvirtuosen
Authors: Roth Klaus
Published: June 2009

Auf der Suche nach “Stradivaris Geheimnis” haben unzählige akustische und chemische Untersuchungen, einschließlich Analysen der Grundierung, des Lacks und der Pigmente, unser Verständnis von der Herstellung und dem Spiel einer Geige vertieft. Blindtests mit Violin‐Experten haben einige Zweifel an der Überlegenheit von Stradivari Violinen aufkommen lassen, so dass vielleicht gar kein Geheimnis existiert. Ein chemische Tatsache ist aber sicher: Geigen entfalten ihren Wohlklang nur nach Einreiben der Bogenhaare mit Kolophonium, einer Mischung verschiedener tricyclischer Diterpene, die über eine protonen‐katalysierte Umlagerung umgelagert worden sind. Dies beweist wieder einmal, die Chemie lässt wirkliche Wunder wahr werden.
Neue intermetallische Supraleitung
Authors: Feil Sylvia
Published: June 2009

Als neue Werkstoffe werden die Materialeigenschaften intermetallischer Eisen‐Arsenid‐Supraleiter untersucht, die ähnlich den bisher bekannten Cupraten zu den Hochtemperatursupraleitern zählen. Wie in den keramischen Cupraten ist auch in den neuen intermetallischen Supraleitern die leitende Schicht zweidimensional. Indem ein elektronisches Phasendiagramm der Leitfähigkeit erstellt wurde, können die Theorien zur Entstehung von Supraleitern überprüft und revidiert werden. Zugleich wurden die Ordnungs‐Parameter der auf Eisen basierenden Supraleiter LaO1–xFxFeAs für Dotierungen von x von Null bis 0,2 erfasst.
Freiberg in Sachsen
Authors: Schwedt Georg
Published: June 2009

Die Gesellschaft Deutscher Chemiker (GDCh) erinnert durch Gedenktafeln und die Herausgabe einer Broschüre an die Wirkungsstätten bedeutender Chemiker und an die Forschung der Wissenschaftler. Auf diese Weise werden einer breiteren Öffentlichkeit historische Wurzeln und das kulturelle Erbe der Chemie bekannt gemacht.
Identification of vasculature‐specific genes by microarray analysis of etsrp/etv2 overexpressing zebrafish embryos
Authors: Wong Kuan Shen , Proulx Kira , Rost Megan S. , Sumanas Saulius
Published: June 2009

Signaling pathways controlling vasculogenesis, angiogenesis, and myelopoiesis are still poorly understood, in part because not all genes important for vasculature or myeloid cell formation have been characterized. To identify novel potential regulators of vasculature and myeloid cell formation we performed microarray analysis of zebrafish embryos that overexpress Ets1‐related protein (Etsrp/Etv2/ER71), sufficient to induce vasculogenesis and myelopoiesis (Sumanas and Lin [2006] Development 121:3141–3150; Lee [2008] Cell Stem Cell 2:497–507; Sumanas et al. [2008] Blood 111:4500–4510). We performed sequence homology and expression analysis for up‐regulated genes that were novel or previously unassociated with the zebrafish vasculature formation. Angiotensin II type 2 receptor (agtr2), src homology 2 domain containing E (she), mannose receptor C1 (mrc1), endothelial cell‐specific adhesion molecule (esam), yes‐related kinase (yrk/fyn), zinc finger protein, multitype 2b (zfpm2b/fog2b), and stabilin 2 (stab2) were specifically expressed in vascular endothelial cells during early development while keratin18 expression was localized to the myeloid cells. Identification of vasculature and myeloid‐specific genes will be important for dissecting molecular mechanisms of vasculogenesis/angiogenesis and myelopoiesis. Developmental Dynamics 238:1836–1850, 2009. © 2009 Wiley‐Liss, Inc.
Theoretical Study of the RNA Hydrolysis Mechanism of the Dinuclear Zinc Enzyme RNase Z
Authors: Liao Rong‐Zhen , Himo Fahmi , Yu Jian‐Guo , Liu Ruo‐Zhuang
Published: June 2009

RNase Z is a dinuclear zinc enzyme that catalyzes the removal of the tRNA 3′‐end trailer. Density functional theory is used to investigate the phosphodiester hydrolysis mechanism of this enzyme with a model of the active site constructed on the basis of the crystal structure. The calculations imply that the reaction proceeds through two steps. The first step is a nucleophilic attack by a bridging hydroxide coupled with protonation of the leaving group by a Glu‐His diad. Subsequently, a water molecule activated by the same Glu‐His diad makes a reverse attack, regenerating the bridging hydroxide. The second step is calculated to be the rate‐limiting step with a barrier of 18 kcal/mol, in good agreement with experimental kinetic studies. Both zinc ions participate in substrate binding and orientation, facilitating nucleophilic attack. In addition, they act as electrophilic catalysts to stabilize the pentacoordinate trigonal‐bipyramidal transition states.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Syntheses, Crystal Structures and Photophysical Properties of Two Doubly μ‐Phenoxo‐Bridged LnIII (Ln = Pr, Nd) Homodinuclear Schiff Base Complexes
Authors: Chakraborty Joy , Thakurta Santarupa , Pilet Guillaume , Ziessel Raymond F. , Charbonnière Loïc J. , Mitra Samiran
Published: June 2009

Two novel homodinuclear isomorphous lanthanide(III) complexes [Ln(api)]2 (where Ln = Pr and Nd for 1 and 2, respectively) with Schiff base anion api3– {H3api = 2‐(2‐hydroxyphenyl)‐1,3‐bis[4‐(2‐hydroxyphenyl)‐3‐azabut‐3‐enyl]‐1,3‐imidazolidine} have been synthesized by a direct reaction of the Schiff base ligand and the corresponding hydrated lanthanide(III) nitrates in methanol. The geometry of each LnIII ion in both complexes is distorted square antiprism (DSAP) as revealed by single‐crystal X‐ray diffraction studies and the structures are found to be centrosymmetric. Both the complexes along with the ligand have been characterized by microanalysis and different spectroscopic techniques. A detailed photophysical investigation has been performed on both the ligand and the complexes. The fluorescence lifetime for the ligand is in the nanosecond regime, suggesting emission from a singlet state. The two lanthanide complexes exhibit NIR luminescence which has been explored throughsolid‐state photoluminescence. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Characterisation and Modelling of a High Temperature PEM Fuel Cell Stack using Electrochemical Impedance Spectroscopy
Authors: Andreasen S. J. , Jespersen J. L. , Schaltz E. , Kær S. K.
Published: June 2009

In designing and controlling fuel cell systems, it is advantageous to have models which predict fuel cell behaviour in steady‐state as well as in dynamic operation. This work examines the use of electro‐chemical impedance spectroscopy (EIS) for characterising and developing an impedance model for a high temperature PEM (HT‐PEM) fuel cell stack. A Labview virtual instrument has been developed to perform the signal generation and data acquisition which is needed to perform EIS. The typical output of an EIS measurement on a fuel cell is a Nyquist plot, which shows the imaginary and real parts of the impedance of the measured system. The full stack impedance depends on the impedance of each of the single cells of the stack. Equivalent circuit models for each single cell can be used to predict the stack impedance at different temperature profiles of the stack. The information available in such models can be used to predict the fuel cell stack performance, e.g. in systems where different electronic components introduce current harmonics.
Basics of standardization and calibration in cytometry – a review
Authors: Mittag Anja , Tárnok Attila
Published: June 2009

Standardization, calibration, and controls (negative and positive controls) are essential for quality assurance. Cytometers are capable of reliable and repeatable cellular analyses. However, a prerequisite is instrument calibration and standardized preanalytics. Calibration is often done by beads. Beads are available for different quality control applications, e.g. calibration of size and measuring scale, compensation, absolute cell counting, and laser alignment. Results can be standardized by converting MFI values into MESF or ABC values. Standardized data allow comparison of experiments over a long period of time and between different instruments and laboratories. Alterations in the sensitivity of the cytometer can be detected by routinely performing quality control. The process of quality assurance quantifies and helps manage the variance from the desired value. Results can thus be compared objectively with those of other laboratories. Standardization is the basis of cytometry and a prerequisite for obtaining reliable data. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Composition and anti‐inflammatory activities of Zanthoxylum schinifolium essential oil: suppression of inducible nitric oxide synthase, cyclooxygenase‐2, cytokines and cellular adhesion
Authors: Lee Je‐Hyuk , Chang Kyung‐Mi , Kim Gun‐Hee
Published: June 2009

BACKROUND: The chemical composition of Zanthoxylum schinifolium essential oil (EO) was analysed by gas chromatography/mass spectroscopy (GC/MS). To date, the biological functions of Z. schinifolium EO have not been demonstrated scientifically. We investigated the composition of Z. schinifolium EO and its potential anti‐inflammatory effects including iNOS and COX‐2 gene transcription, the production of cytokines IL‐1β and IL‐6, and the cellular adhesion.

RESULTS: Over 55 compounds were detected in Z. schinifolium EO, and β‐phellandrene, citronellal, and geranyl acetate were identified as the major constituents. Z. schinifolium EO and its constituents suppressed significantly gene transcription of the inducible nitric oxide synthase and cyclooxygenase‐2 from lipopolysaccharide (LPS)‐induced RAW 264.7 cells. In addition, Z. schinifolium EO inhibited interleukin‐1β production in LPS‐stimulated macrophage cells. The suppression of E‐selectin gene transcription by Z. schinifolium EO caused the cellular adhesion of THP‐1 monocytes to HUVEC monolayers.

CONCLUSION: This study suggests that Z. schinifolium EO may be useful as an alternative medicine for the relief and retardation of immunological inflammatory responses, as well as aromatherapy, and its action may occur through the reduction of inflammatory mediators. Copyright © 2009 Society of Chemical Industry
Optimal efficacy of ribavirin in the treatment of hepatitis C
Authors: Chakrabarty Siddhartha P.
Published: June 2009

A mathematical model to represent hepatitis C is presented. An objective functional keeping biomedical goals in mind is formulated. The optimal control problem is solved numerically to obtain an optimal efficacy of ribavirin in a combination treatment of ribavirin with interferon, where the efficacy of the latter has a clinically validated functional form. Copyright © 2009 John Wiley & Sons, Ltd.
Systematic study of protein sumoylation: Development of a site‐specific predictor of SUMOsp 2.0
Authors: Ren Jian , Gao Xinjiao , Jin Changjiang , Zhu Mei , Wang Xiwei , Shaw Andrew , Wen Longping , Yao Xuebiao , Xue Yu
Published: June 2009

Protein sumoylation is an important reversible post‐translational modification on proteins, and orchestrates a variety of cellular processes. Recently, computational prediction of sumoylation sites has attracted much attention for its cost‐efficiency and power in genomic data mining. In this work, we developed SUMOsp 2.0, an accurate computing program with an improved group‐based phosphorylation scoring algorithm. Our analysis demonstrated that SUMOsp 2.0 has greater prediction accuracy than SUMOsp 1.0 and other existing tools, with a sensitivity of 88.17% and a specificity of 92.69% under the medium threshold. Previously, several large‐scale experiments have identified a list of potential sumoylated substrates in Saccharomyces cerevisiae and Homo sapiens; however, the exact sumoylation sites in most of these proteins remain elusive. We have predicted potential sumoylation sites in these proteins using SUMOsp 2.0, which provides a great resource for researchers and an outline for further mechanistic studies of sumoylation in cellular plasticity and dynamics. The online service and local packages of SUMOsp 2.0 are freely available at: http://sumosp.biocuckoo.org/.
Quantitative analysis of cellular proteome alterations in human influenza A virus‐infected mammalian cell lines
Authors: Vester Diana , Rapp Erdmann , Gade Dörte , Genzel Yvonne , Reichl Udo
Published: June 2009

Over the last years virus–host cell interactions were investigated in numerous studies. Viral strategies for evasion of innate immune response, inhibition of cellular protein synthesis and permission of viral RNA and protein production were disclosed. With quantitative proteome technology, comprehensive studies concerning the impact of viruses on the cellular machinery of their host cells at protein level are possible. Therefore, 2‐D DIGE and nanoHPLC‐nanoESI‐MS/MS analysis were used to qualitatively and quantitatively determine the dynamic cellular proteome responses of two mammalian cell lines to human influenza A virus infection. A cell line used for vaccine production (MDCK) was compared with a human lung carcinoma cell line (A549) as a reference model. Analyzing 2‐D gels of the proteomes of uninfected and influenza‐infected host cells, 16 quantitatively altered protein spots (at least ±1.7‐fold change in relative abundance, p<0.001) were identified for both cell lines. Most significant changes were found for keratins, major components of the cytoskeleton system, and for Mx proteins, interferon‐induced key components of the host cell defense. Time series analysis of infection processes allowed the identification of further proteins that are described to be involved in protein synthesis, signal transduction and apoptosis events. Most likely, these proteins are required for supporting functions during influenza viral life cycle or host cell stress response. Quantitative proteome‐wide profiling of virus infection can provide insights into complexity and dynamics of virus–host cell interactions and may accelerate antiviral research and support optimization of vaccine manufacturing processes.
Interaction of acoustic waves with flame front propagation
Authors: Daubech J. , Sochet I. , Proust Ch.
Published: June 2009

The mechanisms of laminar premixed flame propagation have been intensively studied over the last century. Numerous authors have highlighted intrinsic phenomena in flame propagation such as Darrieus‐Landau instability and Rayleigh‐Taylor instability. Rayleigh‐Taylor instability is often linked to the interaction between the flame front and an acoustic wave.

To better characterize the interaction between a flame and aerodynamic conditions, we designed a special vertical closed tube apparatus. Our analysis focused on the behavior of a flame that propagates in a uniform stoichiometric mixture of H2 and O2 diluted with nitrogen. The experimental investigation revealed that acoustic waves emitted as the flame formed near the ignition point could increase the flame front surface by a factor of 10. An acoustic node with an amplitude of 1.3 m was identified and seemed to be responsible for the disappearance of one of the acoustic modes and for a reduction in the average flame surface. This could explain why the flame trajectory had two distinct parts: one corresponding to propagation at a high speed in the lower part of the tube, and the other with a slower speed in the upper part of the tube. The flame surface seemed to depend primarily on the frequencies of vibration and marginally on the nature of the reactive components. Propagation velocities, obtained by multiplying these flame surfaces by the fundamental burning velocity, strongly depended on the mixture reactivity. © 2009 American Institute of Chemical Engineers Process Saf Prog, 2009
Mass spectrometric study of glucose and cellobiose produced during enzymatic hydrolysis ofα‐cellulose extracted from oak late‐wood annual rings
Authors: Sensuła Barbara M. , Derrick Peter J. , Bickerton John C. , Pazdur Anna
Published: June 2009

We present the first results concerning interannual variations in concentrations of glucose and cellobiose, obtained through enzymatic hydrolysis ofα‐cellulose. Theα‐cellulose was extracted from late‐wood of oak. The tree‐ring chronologies, wood components and their physical and chemical properties provide information about the ecosystem in which the tree grew, and thus information regarding climate variability and the impact of human activity in the past. The large molecular size and insolubility make it difficult to determine precisely the chemical and physical properties of the intact cellulose polymer. Enzymatic hydrolysis is the principal method of degradation of cellulose. In this study the feasibility has been examined of characterizingα‐cellulose through analysis by mass spectrometry (MS) of the degradation products from hydrolysis. Degradation ofα‐cellulose was possible without using alkaline or acid buffers. Analysis by MS provided the opportunity to obtain information on the biodegradation of saccharides. The presence of cellobiose and glucose in the degradation product was evidenced by the mass spectra. We have compared the abundances of these glucose and cellobiose ions with carbon isotope ratios, the efficiency of extraction ofα‐cellulose from the wood and tree‐ring width indices. The challenge is to establish, with respect to climate changes and environmental conditions, the significance of the variations from one year to another in the observed abundances of glucose and cellobiose ions. Copyright © 2009 John Wiley & Sons, Ltd.
A reliable analytical approach based on gas chromatography coupled to triple quadrupole and time‐of‐flight mass analyzers for the determination and confirmation of polycyclic aromatic hydrocarbons in complex matrices from aquaculture activities
Authors: Nácher‐Mestre Jaime , Serrano Roque , Portolés‐Nicolau Tania , Hernández Félix , Benedito‐Palos Laura , Pérez‐Sánchez Jaume
Published: June 2009

The potential of gas chromatography coupled to tandem mass spectrometry (GC/MS/MS) with a triple quadrupole analyzer (QqQ) has been investigated for the quantification and reliable identification of sixteen polycyclic aromatic hydrocarbons (PAHs) from the EPA priority list in animal and vegetable samples from aquaculture activities, whose fat content ranged from 5 to 100%. Matrices analyzed included fish fillet, fish feed, fish oil and linseed oil. Combining optimized saponification and solid‐phase extraction led to high efficiency in the elimination of interfering compounds, mainly fat, from the extracts. The developed procedure minimized the presence of these interfering compounds in the extracts and provided satisfactory recoveries of PAHs. The excellent sensitivity and selectivity of GC/(QqQ)MS/MS in selected reaction monitoring (SRM) allowed to reach limits of detection at pg/g levels. Two SRM transitions were acquired for each analyte to ensure reliable identification of compounds detected in samples. Confirmation of positive findings was performed by GC coupled to high‐resolution time‐of‐flight mass spectrometry (GC/TOFMS). The accurate mass information provided by GC/TOFMS in full acquisition mode together with its high mass resolution makes it a powerful analytical tool for the unequivocal confirmation of PAHs in the matrices tested. The method developed was applied to the analysis of real‐world samples of each matrix studied with the result of detecting and confirming the majority of analytes at the µg/kg level by both QqQ and TOF mass spectrometers. Copyright © 2009 John Wiley & Sons, Ltd.