Interaction of bovine serum albumin (BSA) with ionic surfactants evaluated by electron paramagnetic resonance (EPR) spectroscopy

EPR spectra of 5- and 16-doxyl stearic acid nitroxide probes (5-DSA and 16-DSA, respectively) bound to bovine serum albumin (BSA) revealed that in the presence of ionic surfactants, at least, two label populations coexist in equilibrium. The rotational correlation times (tau) indicated that component I displays a more restricted mobility state, associated to the spin labels bound to the protein; the less immobilized component 2 is due to label localization in the surfactant aggregates. For both probes, the increase of surfactant concentration leads to higher motional levels of component 1 followed by a simultaneous decrease of this fraction of nitroxides and its conversion into component 2. For 10 mM cethyltrimethylammonium chloride (CTAC), the nitroxides are 100% bound to the protein, whereas at 10mM N-hexadecyl-N,N-dimethyl-3-ammonio-1-propanesulfonate (HPS) and sodium dodecyl sulfate (SDS) the fractions of bound nitroxides are reduced to 18% and 86%, respectively. No significant polarity changes were observed in the whole surfactant concentration range for component 1. Moreover, at higher surfactant concentration, component 2 exhibited a similar polarity as in the pure surfactant micelles. For 16-DSA the surfactant effect is different: at 10mM of HPS and CTAC the fractions of bound nitroxides are 76% and 49%, respectively, while at 10 mM SDS they are present exclusively in a micellar environment, consistent with 100% of component 2. Overall, both SDS and HPS are able to effectively displace the nitroxide probes from the protein binding sites. while CTAC seems to affect the nitroxide binding to a significantly smaller extent. (C) 2008 Elsevier B.V. All rights reserved.

Characterization of residential chimney conditions for flue gas flow measurements

A literature survey and a theoretical study were performed to characterize residential chimney conditions for flue gas flow measurements. The focus is on Pitot-static probes to give sufficient basis for the development and calibration of a velocity pressure averaging probe suitable for the continuous dynamic (i.e. non steady state) measurement of the low flow velocities present in residential chimneys. The flow conditions do not meet the requirements set in ISO 10780 and ISO 3966 for Pitot-static probe measurements, and the methods and their uncertainties are not valid. The flow velocities in residential chimneys from a heating boiler under normal operating condi-tions are shown to be so low that they in some conditions result in voiding the assumptions of non-viscous fluid justifying the use of the quadratic Bernoulli equation. A non-linear Reynolds number dependent calibration coefficient that is correcting for the viscous effects is needed to avoid significant measurement errors. The wide range of flow velocity during normal boiler operation also results in the flow type changing from laminar, across the laminar to turbulent transition region, to fully turbulent flow, resulting in significant changes of the velocity profile during dynamic measurements. In addition, the short duct lengths (and changes of flow direction and duct shape) used in practice are shown to result in that the measurements are done in the hydrodynamic entrance region where the flow velocity profiles most likely are neither symmetrical nor fully developed. A measurement method insensitive to velocity profile changes is thus needed, if the flow velocity profile cannot otherwise be determined or predicted with reasonable accuracy for the whole measurement range. Because of particulate matter and condensing fluids in the flue gas it is beneficial if the probe can be constructed so that it can easily be taken out for cleaning, and equipped with a locking mechanism to always ensure the same alignment in the duct without affecting the calibration. The literature implies that there may be a significant time lag in the measurements of low flow rates due to viscous effects in the internal impact pressure passages of Pitot probes, and the significance in the discussed application should be studied experimentally. The measured differential pressures from Pitot-static probes in residential chimney flows are so low that the calibration and given uncertainties of commercially available pressure transducers are not adequate. The pressure transducers should be calibrated specifically for the application, preferably in combination with the probe, and the significance of all different error sources should be investigated carefully. Care should be taken also with the temperature measurement, e.g. with averaging of several sensors, as significant temperature gradients may be present in flue gas ducts.

Selective Synthesis of Oxacalix[6]arenes and Mixed Oxacalix[4]arenes

Calixarenesare macrocycles composed of benzene rings meta linked to each other by one carbon atom. These exotic compounds can be used for a variety of purposes including metalleaching for environmental cleanup, surface technology, luminescent probes, nuclear waste treatment, among others. A variety of calixarenesexist, including azacalix[n]arenesthiocalix[n]arenes(where n = the number of benzene rings) and oxacalix[n]arenes; these macrocycles use nitrogen, sulfur and oxygen, respectively, as the atom whichlinks the benzene rings together. My research has focused on synthesizing oxacalix[6]arenes (“hexamer”) in high yield, which is a synthetic challenge because it is generally accepted that oxacalix[n>4]arenes will thermodynamically decompose to the oxacalix[4]arene (“tetramer”); i.e. heating the reaction mixture will yield the tetramer, not the hexamer. To generate the hexamer, “trimer”precursors have been synthesized, in the hopes of facilitating hexamer ring closure.

Monitoração de protocolos de alto nível através da implementação de um agente RMON2

A área de gerência de rede cresce à medida que redes mais seguras e menos vulneráveis são necessárias, e as aplicações que concorrem pelo seu uso, necessitam de alta disponibilidade e qualidade de serviço. Quando estamos focando a gerência da infra-estrutura física das redes de computadores, por exemplo, a taxa de uso de um segmento de rede, podemos dizer que esse tipo de gerenciamento encontra-se em um patamar bastante sedimentado e testado. Por outro lado, há ainda lacunas para pesquisar na área de gerenciamento de protocolos de alto nível. Entender o comportamento da rede como um todo, conhecer quais hosts mais se comunicam, quais aplicações geram mais tráfego e, baseado nessas estatísticas, gerar uma política para a distribuição de recursos levando em consideração as aplicações críticas é um dever nas redes atuais. O grupo de trabalho IETF RMON padronizou, em 1997, a MIB RMON2. Ela foi criada para permitir a monitoração de protocolos das camadas superiores (rede, transporte e aplicação), a qual é uma boa alternativa para realizar as tarefas de gerenciamento recém mencionadas. Outro problema para os gerentes de rede é a proliferação dos protocolos de alto nível e aplicações corporativas distribuídas. Devido a crescente quantidade de protocolos e aplicações sendo executados sobre as redes de computadores, os softwares de gerenciamento necessitam ser adaptados para serem capazes de gerenciá-los. Isso, atualmente, não é fácil porque é necessário usar linguagens de programação de baixo nível ou atualizar o firmware dos equipamentos de monitoração, como ocorre com os probes RMON2. Considerando este contexto, esse trabalho propõe o desenvolvimento de um agente RMON2 que contemple alguns grupos dessa MIB. O agente baseia-se na monitoração protocolos de alto nível e aplicações que são executados sobre o IP (Internet Protocol) e Ethernet (na camada de enlace). Além da implementação do agente, o trabalho apresenta um estudo de como obter estatísticas do agente RMON2 e usá-las efetivamente para gerenciar protocolos de alto nível e aplicações.

Acessibilidade no ambiente escolar: reflexões com base no estudo de duas escolas municipais de Natal-RN

This work was originated through the results of the analysis of the services for the needs of people with disabilities that were permitted by the physical space of two schools of the municipality of Natal/RN. The general objective/goal was to subsidize the elaboration of alternatives for the planning of environments that could be used by any person. The study used the empirical research through the adoption of a multimethod approach including: (i) technical visits oriented by the NBR 9050, (ii) contact with users that have reduced mobility (visually impaired and wheelchair or crutch users) through escorted travels and interviews, and (iii) interview with school managers. The evidence from the research, even though with significant development of laws that guarantee people with disabilities their right to citizenship, the physical environment of our schools still present with many obstacles that prevent the mobility of people with disabilities which proves their lack of readiness to accommodate them. Therefore, the actions taken to address the accessibility has been the adoption of temporary solutions that makes the adaptation more difficult, adds obstacles and reinforces the undesirable segregation, however still very present in our society. Finally, there is the indication that in order to achieve the spatial configuration that promotes social contact and integration in between the persons with different physical status, it is necessary to completely comprehend the activities developed in each space, from the conception of the equipment to the individual learning needs, having in mind creating environments that stimulates the execution of the tasks in an independent manner without the assistance of others. The inclusion regarding attention to accessibility in the decision making process, directed to the arquitectural and urban project, would decrease the constant need to redevelop and adapt spaces, and should be definitely incorporated as an important component in the production of space

Mapeamento cromossômico de genes ribossomais em espécies estuarinas da família Gerreidae Identificação de uniformidade cariotípica e sua empregabilidade com fins biotecnológicos - REPROGEN

Perciformes are dominant in the marine environment, characterized as the largest and most diverse fish group. Some families, as Gerreidae, popularly known as silver jennies, carapebas, or mojarras have a high economic potential to marine fish farming, natural explotation and game fishing. Genetic information of these species are of fundamental importance for their management and production. Despite exist over 13,000 marine fish species described, only 2% were cytogenetically analyzed and less than 1% have some reproductive characteristics known. Induced breeding, cytogenetic characterization and cryopreservation of gametes, represent important areas in applied fish studies. In this project cytogenetic analyzes were performed to acess genetic aspects of Gerreidae species, distributed in coastal and estuarine regions of Northeast Brazil. Different methods for identifying chromosomal regions were employed using conventional techniques (Ag-NORs, C-banding), staining with base-specific fluorochromes (DAPI-CMA3), and physical mapping of ribosomal genes 18S and 5S rDNA, through hybridization in situ with fluorescent probes (FISH). The six species analyzed showed remarkable chromosome conservatism. The 18S and 5S ribosomal genes when analyzed in phylogenetic perspective demonstrate varied evolutionary dynamics, suggesting ocurrence of stasis process in some groups and greater dynamism in others. Double FISH with 18S and 5S probes showed both how efficient cytotaxonomic markers in the homogeneous karyotypes of this group of species. The karyotypic pattern identified in addition to the evolutionary aspects of karyotype, are suggestive of existence of low potential of post-zygotic barrier, prompting further research to prospect for artificial interspecific hybridization of these species of commercial importance

Significados e percepções de puérperas sobre as síndromes hipertensivas da gravidez e parto prematuro

Hypertensive syndromes in pregnancy (HSP) are configured as one of the major complications in the pregnancy and postpartum period and can lead premature newborn and subsequent hospitalization of the newborn to the Neonatal Intensive Care Unit (NICU). This study aimed to analyze the perceptions, meanings and feelings of mothers on the hypertensive syndromes in pregnancy and premature obstetric labor. The research was qualitative and has a theoretical methodological the Social Representations Theory(SRT) in the approach to the Central Nucleus Theory. The study included 70 women, mean age 29 years, predominantly school to high school, most of them married or in consensual union, primiparous and prevalence of cesarean delivery occurred between 32 and 37 weeks of pregnancy.The data were collected from may to december 2008 in the Maternity School Januário Cicco in Natal , and obtained through the following instruments for data collection: questionnaire including questions about socio-demographic status; the Free Words Association Test (FWAT) and and verbalized mental image construction used three stimuli: such as pregnancy with high blood pressure, preterm birth and NICU, and interview with the following guiding question: what it meant for you to have a pregnancy with high blood pressure and consequently the birth of a premature baby? Data analysis was performed using multi-method obtained from the data processing by EVOC (Ensemble Programmes Permettant L 'Analyze des Évocations) and ALCESTE (Analyse Lexicale par Contexte d'un Ensemble de Segment de Texte) and thematic analysis in categories. The results will be presented in four thematic units under the following representative universes: HSP, prematurity as a result of HSP, NICU and the social representations of mothers on the hypertensive disorder of pregnancy sequenced premature birth and hospitalization of the child in the NICU. The results obtained by multimethod analyses showed similar constructions and point to death as the central nucleus and negative aspects, coping strategies, need of care, knowledge about the disease, fragility and meanings of the NICU as peripheral elements. It is considered that the perceptions, meanings and feelings of puerperal women in relation to HSPs and to premature delivery are a negative social representation, with representational elements that may have influenced the adverse effects on the disease and its consequences. We suggest action on the peripheral elements of this representation, with adequate orientation, early diagnosis, effective conduct, receptive attitude on the part of the team, health promotion measures and effective public policies, in order to improve the care provided to puerperal women, making them feel welcome and minimizing their suffering

Preferential location of lidocaine and etidocaine in lecithin bilayers as determined by EPR, fluorescence and H-2 NMR

We have examined the effect of the uncharged species of lidocaine (LDC) and etidocaine (EDC) on the acyl chain moiety of egg phosphatidylcholine liposomes. Changes in membrane organization caused by both anesthetics were detected through the use of EPR spin labels (5, 7 and 12 doxyl stearic acid methyl ester) or fluorescence probes (4, 6, 10, 16 pyrene-fatty acids). The disturbance caused by the LA was greater when the probes were inserted in more external positions of the acyl chain and decreased towards the hydrophobic core of the membrane. The results indicate a preferential insertion of LDC at the polar interface of the bilayer and in the first half of the acyl chain, for EDC. Additionally, 2 H NMR spectra of multilamellar liposomes composed by acyl chain-perdeutero DMPC and EPC (1:4 mol%) allowed the determination of the segmental order (S-mol) and dynamics (T-1) of the acyl chain region. In accordance to the fluorescence and EPR results, changes in molecular orientation and dynamics are more prominent if the LA preferential location is more superficial, as for LDC while EDC seems to organize the acyl chain region between carbons 2-8, which is indicative of its positioning. We propose that the preferential location of LDC and EDC inside the bilayers creates a "transient site", which is related to the anesthetic potency since it could modulate the access of these molecules to their binding site(s) in the voltage-gated sodium channel. (C) 2007 Elsevier B.V. All rights reserved.

Expression of the sigma35 and cry2AB genes involved in Bacillus thuringiensis virulence

Muitos genes estão envolvidos nos mecanismos de esporulação da bactéria Bacillus thuringiensis. A regulação e expressão desses genes resultam em uma produção massiva da proteína Cry, responsável pela morte das larvas de muitos insetos. Neste trabalho monitorou-se a expressão de genes de Bacillus thuringiensis, ao longo de três fases de seu desenvolvimento. Foram construídos macroarrays de DNA dos genes selecionados, cujas seqüências estão disponibilizadas no GenBank. Estes genes foram hibridizados com cDNAs obtidos de B. thuringiensis kurstaki HD-1. As sondas de cDNA foram sintetizadas a partir da transcrição reversa do RNA da bactéria, extraído durante as fases de crescimento logarítmico, estacionária e esporulativa, marcadas com 33PadCTP. A expressão diferencial encontrada foi significativa para dois genes de B.thuringiensis, um relacionado aos fatores sigma (sigma35) e outro ao gene cry (cry2Ab). Detectaram-se diferenças entre as médias de expressão do fator sigma e do gene cry2Ab. Os valores máximos de expressão diferencial foram obtidos para o gene codificador do fator sigma35 na fase log e na fase esporulativa. Na análise de médias observou-se expressão do gene cry2Ab apenas na fase log; no entanto, de forma bem mais baixa quando comparado com a expressão de sigma35, nas três fases.

Processos carioevolutivos na ordem tetraodontiformes: uma visão através de suas diferentes linhagens

Given the great diversity of fishes, the Order Tetraodontiformes stands to show genetic and morphological characteristics enough singular. The fishes of this order have a compact DNA which favors molecular studies, as well as comparisons with more basal species. Model of genome evolution, there are still many gaps in knowledge about their chromosomal patterns and how evolutionary rearrangements influence the marked variation in DNA content of this order. In view of this, we present cytogenetic analyzes of the species Acanthostracion quadricornis (Ostraciidae), A. polygonius (Ostraciidae) Melichthys niger (Balistidae) Cantherhines macrocerus (Monacanthidae) and C. pullus (Monacanthidae), Lagocephalus laevigatus, Colomesus psittacus and Canthigaster figueiredoi (Tetraodontidae), to contribute with cytogenetic data for this group. The analysis was performed by C-banding, Ag-RONs, coloring with base-specific fluorochromes DAPI-CMA3, restriction enzymes AluI, EcoRI, TaqI, PstI and HinfI and in situ hybridization with probes for ribosomal DNA 18S and 5S. The heterochromatic ultrastructure of A. quadricornis and A. polygonius revealed a outstanding heterochromatin content, which may indicate that the accumulation or loss of extensive heterochromatin content could be responsible for large variations in genomic content displayed in different Tetraodontiformes families. The species Cantherhines macrocerus, C. pullus (Monacanthidae) and Melichthys niger (Balistidae) shows a huge karyotypic similarity both numerically and structural. L. laevigatus showed similar cytogenetic features (2n = 44 and single RONs) to the species of the genus Takifugu, which reinforces the idea of their phylogenetic relationships. C. psittacus presented the highest diploid number described for the family (2n = 56) and large amount of HC, features that related with its sister family Diodontidae. Cytogenetic analysis in C. figueiredoi revealed heterochromatic polymorphisms, RONs multiple and Bs chromosomes. These events are rare in marine fishes, and are possibly associated with the strong restructuring and genomic reduction that this family has been suffered. These features, plus the morphological and molecular data suggests that these species share the same ancestral branch, with a possible monophyletic origin. In this study, new contributions to the knowledge of evolutionary patterns facing by Tetraodontiformes are provided and discussed under cytotaxonomyc, genomic and evolutionary perspectives.

Genetic Diversity of a Brazilian Strain Collection of Xanthomonas citri subsp citri Based on the Type III Effector Protein Genes

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

New genes of Xanthomonas citri subsp citri involved in pathogenesis and adaptation revealed by a transposon-based mutant library

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Distinctively variable sequence-based nuclear DNA markers for multilocus phylogeography of the soybean- and rice-infecting fungal pathogen Rhizoctonia solani AG-1 IA

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Efeito da adição de lodo de estação de tratamento de água (ETA) nas propriedades de material cerâmico estrutural

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Sugarcane bagasse ash as a potential quartz replacement in red ceramic

Sugarcane bagasse ash (SCBA) is an industrial waste that contains silicon and aluminum oxides as the major components and iron, calcium, magnesium, and potassium oxides as the main minor components. In this paper, SCBA from one Brazilian factory was characterized and tested for its influence on the ceramic properties of clay/ash ceramic probes. Prismatic probes were pressed (18 MPa) using a ceramic mass mixed with 0%, 5%, 8%, and 10% ash. The probes were fired at temperatures between 800 degrees and 1200 degrees C. X-ray diffraction, X-ray fluorescence, thermal analysis (differential thermal analysis, thermo-gravimetric analysis/differential thermogravimetric analysis), and tests for texture (particle-size analysis), flexural strength, and linear shrinkage were carried out to characterize the samples. The results showed that the amount of ash to be incorporated will depend on mainly the composition of clay but also ash, and indicated that the clay used in this work can incorporate up to 10% weight of ash to produce solid bricks. The results also showed an improvement in ceramic/ash properties up to sintering temperatures higher than 1000 degrees C.