This paper presents an investigation into the relationship between the announcement of mergers and acquisitions, the existence of positive abnormal returns for shares of these firms, and market efficiency in Argentina, Brazil and Chile. Statistically significant Standardized Abnormal Returns were present in the event announcement and the following days in Argentina and Chile and on the event day in Brazil, confirming value creation signaling. Furthermore, the significance of abnormal returns in the event window, namely in the 5 days following the event in Argentina and Chile and the absence of such in Brazil suggests a more efficient market exists in Brazil, in keeping with the semi-strong market efficiency hypothesis. The absence of semi-strong efficient market behavior could prove valuable to investors who could use a window of a few days after the event announcement to accumulate abnormal returns, provided the appropriate research into news of possible mergers or acquisitions has been made.

O Mismatch Negativity (MMN) é um potencial evocado auditivo endógeno, gerado por mudanças no processo de discriminação que ocorrem no córtex auditivo que avalia a memória sensorial auditiva. OBJETIVOS: Avaliar se, quando presente, o MMN pode ser utilizado como um índice funcional do córtex auditivo supratemporal e correlacionar com comprometimento cognitivo, avaliado pelo Teste Auditivo Compassado de Adição Seriada (PASAT). MATERIAL E MÉTODOS: Um grupo controle e outro com diagnóstico definido de EM foram submetidos ao registro do MMN com estímulos auditivos com variação de duração e de freqüência. O grupo de EM foi submetido ao PASAT. As latências e as amplitudes negativas do MMN foram comparadas entre os grupos. Os escores do PASAT foram correlacionados com a presença ou ausência do MMN nos dois protocolos de estimulação auditiva. RESULTADOS: O MMN esteve presente em 60% dos indivíduos no grupo de EM no protocolo de estimulação auditiva com variação de duração, e em 45% no protocolo de estimulação auditiva com variação de freqüência. Encontrou-se uma correlação estatisticamente significante entre a ausência da onda do MMN com a presença de comprometimento cognitivo avaliado pelo PASAT. CONCLUSÕES: A ausência do MMN se correlaciona com comprometimento cognitivo avaliado pelo PASAT.

Mismatch Negativity is a functional index of the supratemporal auditory cortex. AIM: The aim of the present study on Mismatch Negativity (MMN) in multiple sclerosis (MS) patients was to evaluate if the MMN can be correlated with cognitive deficits assessed by the Paced Auditory Addition Task - PASAT. METHOD: a clinical study in forty females and 20 males separated in two groups: control individuals and those with a definite diagnosis of MS underwent a duration and frequncy MMN. The MMN latencies and negative amplitudes obtained from the MS group were compared to the ones from the control group. The scores from the Paced Auditory Addition Task were correlated either with the presence or the absence of MMN. RESULTS: MMN was found in 60% of the individuals with multiple sclerosis within the auditory stimulation protocol with varied durations, and in 45 % within the auditory stimulation protocol with frequency variations. There were no statistically significant differences in latencies and amplitudes when compared to controls. We found a statistically significant correlation for the lack of MMN wave together with cognitive disorder asserted by the PASAT. CONCLUSIONS: The MMN correlated to the cognitive deficit assessed by the PASAT.

Two new marine metabolites, 3Z, 6Z, 9Z-dodecatrien-1-ol (1) from the ascidian Botrylloides giganteum and 4H-pyran-2ol acetate from the sponge Ircinia felix (4) are herein reported. The known bromotyrosine compounds, 2-(3,5-dibromo-4-methoxyphenyl)-N,N,N-dimethylethanammonium (2) and 2,6-dibromo-4-(2-(trimethylammonium)ethyl)phenol (3), have been isolated from the sponge Verongula gigantea. Serotonin (5) is reported for the first time from the sponge Cliona delitrix, and tambjamines A (15) and D (16) isolated as their respective salts from the nudibranch Tambja eliora. Only tambjamine D presented cytotoxicity against CEM (IC50 12.2 µg/mL) and HL60 (IC50 13.2 µg/mL) human leukemya cells, MCF-7 breast cancer cells (IC50 13.2 µg/mL), colon HCT-8 cancer cells (IC50 10.1 µg/mL) and murine melanoma B16 cancer cells (IC50 6.7 µg/mL).

A investigação química do extrato bruto obtido a partir do meio de crescimento do actinomiceto Streptomyces acrimycini isolado de sedimentos marinhos levou ao isolamento de dois dipeptídeos: a 8-amino-[ 1,4] diazonano-2,5-diona (1) e leucil-4-hidroxiprolina (3). Os compostos foram isolados a partir do seu meio de crescimento por uma série de etapas cromatográficas e identificados pela análise de seus dados espectroscópicos. O esqueleto macrocíclico da 8-amino-[ 1,4] diazonano-2,5-diona foi descrito apenas uma vez nas marinobactinas, sideróforos isolados a partir de uma bactéria marinha do gênero Marinobacter.

The chemical investigation of the crude extract obtained from the growth media of the marine-derived actinomycete Streptomyces acrimycini isolated from marine sediments led to the isolation of two new dipeptide derivatives: 8-amino-[ 1,4] diazonane-2,5-dione (1) and leucyl-4-hydroxyproline (3). The dipeptides were isolated from the growth media by a series of chromatographic steps, and identified by analysis of spectroscopic data. The macrocyclic carbon backbone of 8-amino-[ 1,4] diazonane-2,5-dione has been previously reported only once in marinobactins, siderophores isolated from the marine bacterium Marinobacter sp.

É proposta uma escala de avaliação de desenvolvimento de estádios fenológicos do cafeeiro arábica, com base em fotografias das 12 fases, do período reprodutivo, compreendidas entre o estádio de gemas dormentes e o de grão seco. Durante a safra de 2001/2002, a escala foi utilizada em diferentes cultivares de café em experimentos localizados em Campinas e Mococa, onde se mostrou útil para estudos que vão possibilitar a identificação das variáveis climáticas relacionadas ao desenvolvimento, à expansão e à maturação dos frutos para as diferentes cultivares de café arábica nas diversas regiões de cultivo.

A scale to evaluate coffee phenological stages is proposed based on images of twelve stages, considering lot for reproductive period, from dormant buds up to dry beans (harvest). During the growing season 2001/02 the scale was used for different coffee cultivars in field trials located at Campinas and Mococa, São Paulo State, Brazil. The scale showed to be useful to relate meteorological variation and crop yield, development and maturation period for the different evaluated cultivars.

Os autores relatam um caso de entomoftoromicose intestinal causada por Entomophthorales, em indivíduo de 19 anos, agricultor e sem doença associada. O paciente foi submetido a ressecção intestinal e o diagnóstico foi feito após análise da peça cirúrgica. Após revisão da literatura, são discutidos a evolução clínica, as características clinicopatológicas, as dificuldades no diagnóstico e o tratamento dessa entidade rara.

A case of intestinal entomophthoramycosis caused by Entomophthorales in a man with 19 years-old, farmer and without associated disease. The patient was submitted to a intestinal ressection and diagnosis was carried through after analisys of the surgical specimen. After a review of the literature, the clinical evolution, clinico-pathologic features, difficulties in diagnosis and treatment are discussed.