Eletrodos modificados com DNA: uma nova alternativa em eletroanálise

The first studies about DNA electrochemistry appeared at the end of the fifties. The voltammetric techniques became important tool for the DNA conformational analysis, producing evidences about DNA double helix polimorphism. The new techniques based on electrodes modification with nucleic acid enlarged the use of the electrochemical methods on the DNA research. DNA electrochemical biosensors are able to detect specific sequences of DNA bases, becoming important alternative for the diagnosis of disease, as well as in the carcinogenic species determination. Besides, the use of DNA biosensors in the mechanism study of biological drug actions can be useful for drug design.

7-Epiclusianona, a nova benzofenona tetraprenilada e outros constituintes químicos dos frutos de Rheedia gardneriana

Phytochemical investigation of the fruits of Rheedia gardneriana led to the isolation of sesquiterpenes mixture, methyl esters of fatty acids (palmitate, estearate, oleate, linoleate, linolenate), sugars (galactose, glucose, fructose), triterpene (oleanolic acid), steroids mixture (stigmasterol and sitosterol) and the new tetraprenylated benzophenone 7-epiclusianone.

Els Intel·lectuals de "La Nova Catalunya" de L’Havana

L’objectiu principal d’aquest treball és analitzar les característiques i motivacions dels intel·lectuals que es relacionaren amb Cuba durant les primeres dècades del segle XX, a partir dels casos particulars de Josep Conangla i Fontanilles (Montblanc, 1875 – L’Havana, 1965), representant de les figures que s’establiren a l’Illa, i Prudenci Bertrana (Tordera, 1867 – Barcelona, 1941). Aquests intel·lectuals van mantenir relacions de col·laboració amb la comunitat del Centre Català de L’Havana

Una nova xarxa social: RFV (Reusencs de fora vila) : Aprofitar el potencial del segle XXI

A partir de l'anàlisi d'un fet local, proposo la creació d'una nova xarxa social que permeti connectar els reusencs que viuen i treballen fora de Reus, i que estan escampats pel món. De Reus al món s'oferirà informació d'allò que passa a la ciutat i del món a Reus es retornarà talent, idees i connexions. Analitzarem les xarxes socials, el seu origen, la web 2.0, quines són les xarxes socials amb més presència arreu del planeta. Situarem en context les relacions que la ciutat de Reus manté amb els seus fills il·lustres, i amb aquells que han decidit progressar lluny de la ciutat. Avaluarem quina és la millor fórmula per crear una nova xarxa social i amb quines eines s'haurà de construir. L'objectiu de tot plegat és una nova xarxa social: RFV.

Entre Europa i Amèrica Llatina: Adolphe Ferrière i l’Escola Nova a Barcelona

El 1930 Adolphe Ferrière va viatjar durant vuit mesos per Amèrica Llatina, Portugal i Espanya. En el marc del viatge va fer una breu estada de pocs dies a Barcelona, on fou acollit per reconeguts personatges de la pedagogia catalana i va desplegar una intensa activitat pública i privada de visites, entrevistes, conferències i excursions. En el programa d'activitats s'hi compte la conferència d'inauguració del Seminari de Pedagogia de la Universitat de Barcelona, que dirigia Joaquim Xirau. En aquest article s'analitzen els objectius, les motivacions i els resultats del viatge en el context de la pedagogia ginebrina del període d'entreguerres i en el marc de la trajectòria vital i el pensament de Ferrière. A partir de les notes manuscrites del seu Petit Journal podem resseguir l'activitat de Ferrière a Barcelona, copsar les impressions, conèixer les persones amb qui es va relacionar i, en definitiva, endinsar-nos dins el moviment de l'Escola Nova a Barcelona. L'anàlisi de les idees desenvolupades a les conferències és un bon pretext per revisar alguns conceptes claus del pensament educatiu de Ferrière. A més, s'ha reconstruït el text de l’esmentada conferència, amb el títol «La psicologia de l'adolescència», que publiquem a la secció «Documents» d’aquest mateix número de Temps d’Educació.

Enzymeless biosensors: uma nova área para o desenvolvimento de sensores amperométricos

The aim of this work is to describe the recent area that it has been developed for the construction of amperometric sensors, with the purpose to make possible a more effective electron transfer between enzyme and electrode. The advances reported in the literature will be described, such as enzymatic configurations that can be mimic using the chemistry of the artificial enzymes.

Agentes antineoplásicos biorredutíveis: uma nova alternativa para o tratamento de tumores sólidos

A problem often encountered in cancer therapy is the presence of tumor cell subpopulation that are resistant to treatment. Solid tumors frequently contain hypoxic cells that are resistant to killing by ionizing radiation and also by many chemotherapeutic agents. However, these hypoxic cells can be exploited for therapy by non-toxic hypoxic-activated prodrugs. Bioreductive drugs require metabolic reduction to generate cytotoxic metabolites. This process is facilitated by appropriate reductases and the lower oxygen conditions present in solid tumors. The unique presence of hypoxic cells in human tumors provides an important target for selective cancer therapy.

Análise de glicocorticosteróides por CG-EM: uma nova abordagem de derivatização para o controle de dopagem no esporte

Glucocorticosteroids (CT) show a powerful anti-inflammatory effect. In view of this, they are extensively used in sports medicine, but their misuse (systemic administration) can lead to severe injuries on athletes and has been restricted by the IOC in recent years. For GC-MS analysis, a derivatization step is necessary in order to convert them to a stable form, thus preventing thermal breakdown with the loss of the ketone side chain. Derivatization of CT is reviewed and a new approach of silylation is presented for screening of CT in urine.

SPR: Uma nova ferramenta para biossensores

This paper reviewed the development and theoretical aspects of surface plasmon ressonance (SPR) technique and discusses this powerful sensor technology in the development of biosensors, as well as for the investigation of biological interactions and clinical assays. The SPR has been proven to be a valuable tool to investigate dynamic processes, such as adsorption, degradation, determination of dieletric properties, association/dissociation kinetics, affinity constants of specific ligand-ligate interactions, allowing real-time analysis at almost any surface. The SPR as a complementary technique alongside electrochemical methods is also presented.

A extração de cafeína em bebidas estimulantes: uma nova abordagem para um experimento clássico em química orgânica

Caffeine extraction procedures from water soluble and water insoluble materials for preparing stimulating beverages are described. Water soluble materials used were instant tea and coffee and water insoluble materials were, among others, guaraná powder and maté leaves. The extraction of caffeine from water soluble materials, especially instant tea, is more suitable for an organic chemistry teaching laboratory than the classic experiment using tea leaves, due to the economy of time and a larger amount of extracted caffeine. The procedure is time-saving and requires only a four-hour period. The experiments illustrate the extraction process as used in undergraduate organic chemistry laboratories.

Quantificação do linalol no óleo essencial da Aniba duckei Korstermans utilizando uma nova coluna capilar POLYH4-MD em Cromatografia Gasosa

In the present work a polyurethane polymer derived from castor oil was used as stationary phase for capillary gas chromatography. The polymer was obtained by reaction of hydroxylated compound and isocynate (NCO), forming urethane. Columns of 7 m x 0,25 mm were then coated with this stationary phase (film thickness of 0,25 µm) using static coating method. The Grob test was also performed. Samples of essential oil of the Aniba duckei Korstermans was then analysed in POLYH4-MD capillary column in order to evaluate its chromatographic perfomance. The linalool was found to be the major component and has been used as compound of departure for many important syntheses. Results show that the experimental columns give higher resolution and can be employed for analysis of essentials oils.

Química geral experimental: uma nova abordagem didática

This essay describes a new didactic approach, in according with the national curriculum guidelines for chemistry undergraduate courses in Brazil, employed during the one-semester course "Experimental General Chemistry" for chemistry undergraduate students at the Federal University of Piauí. The new approach has positively helped student's training by improving their reading skills and their understanding of scientific reports, by developing the use of electronic tools to search and to recover the required knowledge for their learning activities, and by improving their skills of understanding published texts and dealing with digital sources. At the same time the students are strongly stimulated to enter the research program for undergraduate students available at the University.

Nova Casa Consistorial de Bigues i Riells

Award-winning

Projecte modificat per a les obres de nova construcció 1 línia de l'Escola l'Olivar de Castellnou de Bages

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