Abstract: The article examines a document from a confraternity dedicated to the Immaculate Conception in Sayula, written in Nahuatl through the seventeenth century. The members of the brotherhood inform that they rented out a piece of land. The house, however, has been occupied by a Spaniard and they request to have it back. The text allows us to take sight of a small part of the daily life of a confraternity, a Christian brotherhood which was well accepted among the Indigenous communities of New Spain. Its existence provided them an opportunity of being autonomous within the colonial regime.

Resumen: El artículo revisa un documento procedente de la cofradía de la Purísima Concepción de Sayula, escrito en náhuatl en el siglo XVII. En él, los cofrades informan que arrendaron tierra de la cofradía. Sin embargo, la propiedad ha sido ocupada por un español y piden que se les devuelva. El documento permite asomarnos a una parte de la cotidianeidad de una cofradía, forma de organización muy extendida en las comunidades indígenas de Nueva España y que les permitía un margen de autonomía dentro del sistema.

ABSTRACT Detection of virulent strains associated with aquatic environment is a current concern for the management and control of human and animal health. Thus, Vibrio diversity was investigated in four estuaries from state of Ceará (Pacoti, Choró, Pirangi and Jaguaribe) followed by antimicrobial susceptibility to different antimicrobials used in aquaculture and detection of main virulence factors to human health. Isolation and identification were performed on TCBS agar (selective medium) and dichotomous key based on biochemical characteristics, respectively. Nineteen strains of genus Vibrio were catalogued. Vibrio parahaemolyticus (Choró River) and V. alginolyticus (Pacoti River) were the most abundant species in the four estuaries. All strains were submitted to disk diffusion technique (15 antimicrobials were tested). Resistance was found to: penicillin (82%), ampicillin (54%), cephalotin (7%), aztreonan (1%), gentamicin, cefotaxime and ceftriaxone (0.5%). Five pathogenic strains were chosen to verification of virulence factors. Four estuaries showed a high abundance of species. High number of tested positive strains for virulence is concerning, since some of those strains are associated to human diseases, while others are known pathogens of aquatic organisms.

The occurrence of psychrotrophic bacteria in raw milk is studied worldwide due to the difficulties associated with controlling their growth during cold storage and the consequent negative effects upon fluid milk or dairy products. Among the psychrotrophic bacteria, the genus Pseudomonas (represented primarily by P. fluorescens) has been highlighted as the cause of numerous defects in dairy products. In light of its perceived predominance, this species has frequently been chosen as a model organism to assess the effects of psychrotrophic bacteria on milk or to evaluate the efficacy of control measures. However, recent findings derived from the application of molecular biological techniques have exposed a number of deficiencies in our knowledge of the biology of milk-associated psychrotrophs. Furthermore, it has been revealed that microbe to microbe communication plays a significant role in determining both the identities and the extent to which different groups of microbes develop during cold storage. The application of molecular identification methods has exposed errors in the classification of members of the genus Pseudomonas isolated from cold stored milk and has stimulated a reevaluation of the presumed status of P. fluorescens as the predominant milk-associated psychrotrophic species. This article presents a succinct review of data from studies on psychrotrophic bacteria in milk, some of which contest established theories in relation to the microbiology of cold stored raw milk, and poses the question: how much do we really know?

Important climatic variations have occurred during the last millennium. After the "Medieval Warming" period, a long period of cold conditions, called "Little Ice Age", took place, being followed by the current "Global Warming". Transient scenarios have been developed using the General Circulation Model ECHO-G to simulate the monthly anomalies for the period 1000-1990 AD. Firstly, the research analyses the ability of ECHO-G model to reproduce the temperature and zonal wind component at 1000hPa over southern South America in the period 1961-1990 to contrast the outputs with the NCEP/NCAR Reanalysis data. The difference of means and standard deviations has been tested for both temperature and zonal wind. In central-north Argentina, ECHO-G simulates higher temperatures than the NCEP/NCAR Reanalysis. However, the differences between model and reanalysis are smaller in the Patagonia region, especially close to the Cardiel Lake. Hence, extended simulations for the last millennium can be used to analyse paleoclimatic variations in such region. Although anomaly patterns between Maünder and Dalton solar Minimums are similar with respect to the 1960-1990 period, their amplitudes are higher for the Maünder Minimum. The alternating light and dark laminae (annual rythmites or varves) from the Cardiel Lake sediments in central Patagonia were previously interpreted as the result of regional wind intensity variations. In this work their thickness time series has been compared with the local zonal wind component and temperature time series at 1000hPa in the period 1000 AD and 1990 AD. A centered 80-years moving average has been applied to these time series to enhance the effect of the Gleissberg solar cycle and other lower frequency periodicities. The results show a reverse relationship between the zonal wind component and the thickness of the dark laminae. Such an inference is confirmed employing Coherence Wavelet Spectrum between the time series. The latter indicates that the thickness of the dark laminae can be used as a proxy for the strengthening of the zonal wind component over Patagonia.

Durante el último milenio han ocurrido importantes variaciones climáticas. Luego de la "Anomalía Climática Medieval" tuvo lugar un prolongado período de generalizadas condiciones frías llamado "Pequeña Edad de Hielo" seguido por el actual "Calentamiento Global". Con el Modelo de Circulación General ECHO-G se produjeron escenarios transientes que simulan las anomalías mensuales del período 1000 a 1990 AD. En este trabajo primeramente se analiza la capacidad del ECHO-G de reproducir los campos de temperatura y componente zonal del viento, ambos en el nivel de 1000hPa, en la región del cono sur de Sudamérica utilizando como referencia el re-análisis NCEP/NCAR para el período 1961-1990 testeando las diferencias de los valores medios y los desvíos estándar para la temperatura y la componente zonal del viento. En el centro norte del país el modelo ECHO-G simula temperaturas superiores a las del re-análisis NCEP-NCAR. Sin embargo, las diferencias entre el modelo y el re-análisis son menores en la Patagonia y particularmente despreciables en la región del Lago Cardiel. Por lo cual las simulaciones de los últimos 1000 años pueden ser utilizadas para analizar la variabilidad paleoclimática de esa región. Los patrones de anomalías para los Mínimos solares de Maünder y Dalton obtenidos con el ECHO-G respecto al período 1961-1990 resultan similares pero más intensos en el caso del Mínimo de Maünder. Las láminas alternantes claras y oscuras (ritmitas anuales o varves) de los testigos sedimentarios del Lago Cardiel en Patagonia central han sido previamente interpretadas como el resultado de la intensidad de los vientos regionales. En el trabajo además se comparara los espesores de dichas láminas con los valores de la componente zonal del viento y la temperatura en 1000hPa para el período comprendido entre los años 1000 a 1990 AD. Las series filtradas con promedios móviles de 80 años, que realzarían el efecto del ciclo de Gleissberg y otras periodicidades solares de menor frecuencia, sugieren relación inversa principalmente entre la componente zonal del viento y los espesores de las láminas oscuras. Esta inferencia es confirmada mediante los espectros de onditas de coherencia entre ambas series. Este primer resultado indicaría que la serie de espesores de láminas oscuras podría ser utilizada como "proxy" dato de la intensidad de la componente zonal del viento sobre la Patagonia.

Objetivou-se, com o presente trabalho, avaliar e comparar o desempenho de três estratégias de aeração de milho armazenado quanto à ocorrência de fungos e à condutividade elétrica dos grãos. As estratégias avaliadas foram: aeração contínua; aeração noturna e aeração em condições de umidade de equilíbrio entre os grãos e o ar ambiente. Realizaram-se dois ensaios de aeração com grãos de milho secos (11% b.u.) e úmidos (17% b.u.). Amostras de grãos foram retiradas durante os ensaios para contagem de fungos e medida da condutividade elétrica dos grãos. Grãos armazenados úmidos apresentaram maior ocorrência de fungos do que grãos armazenados secos. Observou-se que o Fusarium spp. apresentou contagens mais elevadas, o Penicillium spp. manifestou desenvolvimento e o Aspergillus spp. ocorreu com menor frequência. As estratégias de aeração empregadas não interferiram na condutividade elétrica dos grãos de milho armazenados, visto que não houve diferença significativa dos valores de condutividade elétrica entre os grãos submetidos a aeração e os grãos armazenados sem aeração.

The aim of this study was to evaluate and to compare the performance of three aeration strategies for stored corn as for occurrence of molds and electrical conductivity of grain: continuous aeration; night aeration and aeration under equilibrium moisture content conditions between the grains and the ambient air. Two tests of aeration with dry corn grain (11% w.b.) and wet corn (17% w.b.) were done. Grain samples were taken during testing for counting of molds and measuring of electrical conductivity of grains. Wet corn stored had increased incidence of molds more than dry corn stored. It was observed that the Fusarium spp. showed higher scores, Penicillium spp. showed development and Aspergillus spp. occurred with lesser frequency. Aeration strategies employed did not affect the electrical conductivity of corn stored because there was no significant difference in electrical conductivity values between the aerated grain and non-aerated grains.

The objective is to analyze the interannual to interdecadal variability in summer and winter precipitation on the northern argentine Patagonia region, called Pampa Amarilla (RPA), during 1969-2006. The annual 28 regime shows a strong change on annual cycle along the northeast-southwest transect in the RPA. Towards the northeast the annual cycle of precipitation has the maximum records with winter minima and summer equinoccial maxima (March). Towards the southwest the records are smaller, with uniform distribution throughout the anual cycle, presenting slight winter minimum. The observed frequency distribution of the precipitation anomalies tends to show greater occurrence of negative frequencies in the interval (- 100; 0)mm with a slight major probability of occurrence of positive anomalies interval (right tail). The interannual variations for the warm period show, over the north sub-region, a positive and significative trend. An exception is the central region which trend is negative and significative. In the cold season, positive and significative trends are observed, especially in the north and in the southeast areas of the RPA. The RPA can be chracterized by devicing two precipitation indices, one for summer and the other for winter. The indices do not show significant trends. For the summer it is possible to split the región into two: one the northern RPA and the other the southern RPA, with diverse inter-annual behavior. In the northern the dominant cycles are 5 years and to 8 years, and in the southern, around 2-4 years, 11 years and 15 years. During the winter the whole RPA behaves as a uniform region with significant cuasi-cycles around 4-5 years and 11 years. For both summer and winter the regional precipitation indices do not show significant trends. The low-frequency processes between 2 and 6 years could be related to the Southern Annular Mode (SAM). The solar cuasi-cycle could be also involved. For the summer, the tropospheric circulation of lower levels is different in northern and southern RPA. The centers of precipitation at northern RPA are located towards mid-latitudes over the the Argentine Sea. Those associated with the precipitation in southern RPA, are located towards higher latitudes. Generally, anticyclonic activity on the Argentine Sea and Patagonia in high latitudes, can be associated with moisture advection from the east and more precipitation. However, the cyclonic activity at mid-latitudes around the Patagonia inhibits the precipitation. Over the Pacific side, the induced circulation centers seems to act by blocking the westerlies. For winter the precipitation is more associated to westerlies intensified in southern Pacific. The Niño- Southern Oscillation (ENSO) also seems to have influence on the summer precipitation.

Se estudia la variabilidad interanual e interdecádica de la precipitación de verano y de invierno en la región norte de la Patagonia argentina, denominada Pampa Amarilla (RPA), para el período 1969-2006. El régimen anual muestra un marcado cambio del ciclo anual sobre una transecta noreste-sudoeste que atraviesa RPA. Hacia el noreste el ciclo anual de precipitación presenta los mayores registros, y muestra marcado mínimo invernal junto con máximo estival equinoccial (marzo). Hacia el sudoeste, los registros son menores, con uniforme distribución a lo largo del ciclo anual, presentando mínimos invernales ligeros. La distribución de frecuencia observada de las anomalías de precipitación, para verano e invierno, tienden a mostrar una mayor ocurrencia de frecuencias negativas en el intervalo (-100; 0)mm, con una ligera mayor probabilidad de ocurrencia de extremos positivos. Las tendencias de las series del semestre cálido son positivas y significativas hacia el norte, con excepción en la zona centro. Para el semestre frío, las tendencias son positivas y significativas en el norte y sudeste de la RPA. Es posible caracterizar toda la RPA mediante dos índices de precipitación para verano e invierno, respectivamente. Estos índices de precipitación regional no presentan tendencia significativa. El verano puede subdividirse en dos subregiones, norte y sur, con diverso comportamiento interanual. En el norte los ciclos dominantes son de 5 años a 8 años; y en el sur, en las bandas 2-4 años, ca. 11 años y ca. 15 años. El invierno presenta una variabilidad interanual espacialmente homogénea con cuasi-ciclos significativos en torno a 4-5 años y 11 años. En ambas estaciones, los procesos de baja frecuencia de entre 2 y 6 años podrían estar relacionados al Modo Anular del Sur (MAS). El cuasi-ciclo solar podría estar involucrado también. Para veranos, la circulación troposférica de capas bajas, asociada a precipitación, también es discriminante entre norte y sur. Los centros de acción asociados a la precipitación en la subregión norte se localizan hacia latitudes medias sobre el Mar Argentino. Los asociados a la precipitación en la subregión sur se localizan hacia más altas latitudes. En general, actividad anticiclónica sobre la sobre el Mar Argentino y Patagonia de latitudes medias está asociada al ingreso de humedad desde el este y mayor precipitación sobre RPA en verano. En cambio, la actividad ciclónica en dicha región inhibe la precipitación. Para el invierno, la precipitación está más asociada a oestes más intensificados sobre el sur del Pacifico. El Niño-Oscilación del Sur (ENOS) parece también afectar la precipitación de verano.

The Little Ice Age (LIA) was a cold period that ranged from taken part of the century XIV until taken part of the century XIX. In the period occurred three pulses of minimum values of temperature and will study the second of them comprised between 1645-1715 designated Maunder Minimum (MM). The decrease of the solar activity, the increase of the volcanic activity and the change in the Carbon Dioxide concentrations were the main forcings during these periods. In present work we realize distinct simulations of the climatic conditions for the South Hemisphere, by means of the General Circulation Model EdGCM, with the end to obtain stages of answer to the changes of irradiance and CO2 for the MM. At the same time, the climatic differences between years of maxima and minimum values of sunshine during the century XX determined by means of the results of the re-analysis of the NCEP/NCAR, compare with the differences between the current conditions and the ones of the MM, simulated by the model. The anomalies between the XX century and the MM obtained with the EdGCM are in agree qualitatively, and also quantitatively in some locations, with the proxy data information for various regions of the Hemisphere South. The annual temperature anomalies, between the MM and the 20th century ending conditions, are negative for both hemispheres and the temperature anomalies result more intense on semester November-April. Furthermore, over South America, shows a more intense centre in subtropical latitude and central and south Patagonia. The cold pattern obtained by the model is in agreement, on magnitude too, with proxy information obtained in some South America regions. The westerly wind component undergoes a shift to lower latitudes during the MM. The atmospheric circulation anomalies obtained in the simulations, show a pattern, over middle and high latitudes, where alternate three or four positive and negative anomaly centres, which is in agreement with a greater meridional component of the flux. Both patterns are similar to those present during El Niño events.

La Pequeña Edad de Hielo fue un período frío que abarcó desde mediados del siglo XIV hasta mediados del siglo XIX. Durante ese tiempo ocurrieron tres pulsos de temperaturas extremadamente bajas. En el presente trabajo se analiza el segundo de ellos denominado Mínimo de Maunder (MM) que ocurrió entre 1645 y 1715. La disminución de la actividad solar, el aumento de la actividad volcánica y el cambio en las concentraciones de Dióxido de Carbono fueron sus principales forzantes. Mediante el Modelo de Circulación General EdGCM se realizan distintas simulaciones de las condiciones climáticas, con el fin de obtener escenarios de respuesta de la temperatura y la circulación atmosférica a los cambios producidos en la irradiancia y los gases invernadero, en especial del CO2. A su vez, son calculadas por medio de los re-análisis del NCEP/NCAR, las diferencias climáticas entre años de máxima y minima irradiancia a fin de compararlas con las diferencias ocurridas entre las condiciones actuales y del MM dadas por el modelo. Las anomalías anuales de temperatura, entre el MM y las condiciones de fines del siglo XX, son negativas para ambos hemisferios y las anomalías de temperatura resultan más intensas para el semestre frío. Además, sobre Sudamérica, se observa un centro más intenso en latitudes subtropicales y desde el centro hasta el sur de Patagonia. El patrón de enfriamiento simulado por el modelo concuerda, en algunos casos aún en magnitud, con la información de proxy datos de algunas regiones de Sudamérica. La componente zonal del oeste se muestra desplazada hacia menores latitudes durante el MM. Los campos de anomalías de circulación atmosférica simulados para el MM, muestran un patrón, en latitudes medias y altas, en que alternan tres ó cuatro centros positivos con negativos, el cual concuerda con una mayor componente meridional del flujo. Ambos resultan patrones parecidos con los que ocurren actualmente durante eventos El Niño.

The correlation between an index of potential water storage (PWS) with magnetic signal in soils and paleosoils, developed in loessic sediments has been proposed. The analyzed data suggest the existence of climatic thresholds that affect the genesis, preservation or depletion of ferrimagnetic minerals. Soils and paleosoils characterized by a positive PWS have an appropriate environment that favors the depletion of ferrimagnetic minerals due to mainly reductive loss. Such soils are characterized by a depletion of detrital ferrimagnetic minerals, as in northeastern Pampean plain soils and paleosoils of Argentina and SE of China. A negative PWS prevents highly reducing conditions in the soil, and the detrital ferrimagnetic minerals are preserved. On the other hand, the environmental conditions of these soils allow the formation of new nannoparticle minerals. These conditions produce a net magnetic enhancement of the soil, as observed in European soils (Russia, Czech Republic, Rumania), Asian (paleosoils from the loess plateau of China) and Northern African ones (Tunisia). The influence of parent material in the magnetic signal is also discussed.

Se propone la correlación de la señal magnética, registrada en suelos y paleosuelos desarrollados en sedimentos loéssicos, con un índice climático (Potencial de almacenamiento de agua, PWS). Los datos analizados sugieren la existencia de umbrales climáticos que afectan la génesis, preservación ó pérdida de minerales ferrimagnéticos. Suelos y paleosuelos con un índice PWS positivo se caracterizan por ambientes que favorece la pérdida de minerales ferrimagnéticos, la que se debe principalmente a procesos de reducción. Estos suelos presentan pérdida de fracción ferrimagnética detrítica como los del NE de la llanura pampeana y SE de China. Por el contrario, PWS negativos previenen condiciones reductoras en el ambiente con lo cual se preservan los minerales ferrimagnéticos detríticos. Por otra parte, las condiciones estacionales de estos suelos permiten la formación de nuevas nanopartículas magnéticas. Estas condiciones producen un neto enriquecimiento en minerales ferrimagnéticos como el observado en suelos de Europa (Rusia, República Checa y Rumania), Asia (paleosuelos del plateau de China) yNorte de África (Túnez). Se discute asimismo, la influencia del material parental en la señal magnética pedogenética.

Los avances científicos en el campo de la química y de la medicina se han apropiado la inquietud popular que desde hace muchos años utiliza los recursos que ofrece la naturaleza. La planta Cannabis sativa ha sido tradicionalmente utilizada con propósitos medicinales, así como con fines recreativos. Sin embargo, sus importantes efectos psicoactivos han constituido una limitante para su uso. Algunos gobiernos han comenzado a permitir su uso de forma controlada, con fines medicinales. El descubrimiento de compuestos endógenos con propiedades similares a los cannabinoides (endocanabinoides), y el previo conocimiento de los receptores CB1 y CB2, sobre los cuales actúan, ha despertado interés en el mundo entero por descubrir nuevas rutas terapéuticas para el tratamiento de diferentes patologías. Las posibilidades de aprovechar la estructura de los endocanabinoides para diseñar nuevas moléculas con actividad antineoplásica están llevando a enfrentar este reto, buscando fármacos tan eficaces como los actualmente utilizados pero con menos efectos tóxicos. Se está avanzando en el conocimiento de los aspectos moleculares de muchos de estos compuestos, así como en las rutas bioquímicas sobre las cuales actúan.

Scientific advances in Chemistry and Medicine now study wise ancestral popular usages of natural resources. Cannabis sativa has been traditionally used for medicinal and recreational purposes. However, its important psychoactive effects limit its use. Some governments allow its controlled use for medicinal purposes since the discovery of endogenous compounds with similar properties to cannabinoids (endocannabinoids) combined with the previous knowledge on CB1 and CB2 receptors on which they act. A great interest to discover new therapeutic substances for several pathologies treatment has grown increasingly the world over. The possibilities to take advantage of the endocannabinoids structures to design new molecules with antineoplastic activity are coming closer to this challenge, which looks for new efficient drugs like those used today, but less toxic. Knowledge of the molecular aspects of many of these compounds as well as the biochemical ways on which such compounds act, attract now more interest everywhere.

Este trabalho registra pela primeira vez o histórico da contaminação e as fontes de 38 elementos em sedimentos do sistema estuarino de Santos-Cubatão (SE do Brasil), em uma das áreas mais industrializadas da América Latina. A composição de um testemunho de 260 cm de profundidade do estuário do rio Morrão foi determinada por ICP-MS e avaliada por meio de fatores de enriquecimento, análise de componentes principais, matrizes de correlação e assinaturas geoquímicas. Elementos contaminantes como Cr, Mn, Ni, Zn, Ga, Ag, Cd, Sn, Sb, Pb e Bi foram associados ao Fe, derivados de atividades siderúrgicas, enquanto Be, Ca, Sc, Co, Cu, Sr, Y, Zr, Nb, Hf, Ta, Th e U estiveram associados ao P, relacionados ao processo produtivo de fertilizantes. Uma sobreposição da distribuição do Fe sedimentar e produção local de aço indicaram que o Fe é um marcador confiável do histórico da contaminação, permitindo a estimativa de taxas de sedimentação para 45 anos de atividades industriais.

This paper records for the first time the contamination history and identifies the sources of 38 elements in sediments from the Santos-Cubatão Estuarine System (SE Brazil), at one of the most industrialized areas in Latin America. The compositions of samples from a 260 cm long sediment core collected in the Morrão River estuary were determined by ICP-MS. Enrichment factors, principal component analysis, correlation matrixes, and the characterization of geochemical signatures permitted a consistent data evaluation. Contaminant elements such as Cr, Mn, Ni, Zn, Ga, Ag, Cd, Sn, Sb, Pb, and Bi were associated with steel plant-derived Fe concentrations, while Be, Ca, Sc, Co, Cu, Sr, Y, Zr, Nb, Hf, Ta, Th, and U were associated with fertilizer industry-derived P concentrations. An overlap of sedimentary Fe distribution and local steel plant production indicated that Fe is a reliable marker of the contamination history, allowing the estimation of sedimentation rates over a period of 45 years of industrial activities.

In this paper the most frequent spatial patterns of sea ice concentration anomalies (SICA) over the Amundsen, Bellingshausen and Weddell Seas have been obtained from monthly mean values of sea ice concentrations provided by the Scanning Multichannel Microwave Radiometer and the Special Sensor Microwave/Imager of NASA Goddard Space Flight Center for the period 1979 2000. Using analysis of Principal Components (PCs) in T-Mode rotated Varimax, six PCs were obtained. Therefore, a total of 12 patterns were found with six in direct mode (SICA of the same sign that the PC) and six in inversely (SICA of opposite sign to the PC), that classify 95.5 % of the monthly fields. Three PCs describe the most frequent winter-spring cases (period with major concentration and expansion of sea ice) and three PCs correspond to summer-autumn (minor concentration and retraction of the field of ice). Winter-spring months have mainly situations close to the first and second PCs. The 2°PC shows a 30 ° counter wise rotation with respect to the 1°CP and both present dipole anomalies between the seas at both sides of the Antarctic Peninsula. These two components display a recurrence of approximately 4 years in which alternatively the exterior region of the Weddell Sea has conditions of sea ice above the mean values meanwhile, in the north of the Amundsen Sea, the anomalies are negative and vice versa. The most frequent condition with an annual summer - autumn recurrence (3ºCP) is also a dipole but between the interior of the Weddell and the coastal region of Amundsen-Bellingshausen because these is the region where the sea ice is presented in this epoch of the year. The 4 º, 5 º and 6 º components refer to different, and not descript in the literature, conditions of SICA. The summer-autumn PCs, fundamental for the Antarctic navigation, show a change of behavior occurred at the end of the 80s years, in that the Amundsen and Bellingshausen Seas passed of having bigger to minor concentrations of sea ice. The SICA spatial distribution during the mature phases El Niño showed great variability among events and in some cases have opposite behavior for different events. The same occur for La Niña. The influence of the ENSO cycle is relatively clear only for the winter that follows the summer mature phase of the El Niño or La Niña.

En el presente trabajo se han obtenido los patrones espaciales más frecuentes de los campos de anomalías de concentración de hielo marino (ACHM) en los mares de Amundsen, Bellingshausen y Weddell a partir de los valores medios mensuales de concentración de hielo marino provistos por la NASA Goddard Space Flight Center derivados del Scanning Multichannel Microwave Radiometer y Special Sensor Microwave/Imager para el período 1979 al 2000. Haciendo uso de la técnica de análisis de Componentes Principales (CPs) en modo-T rotadas Varimax, se obtienen seis CPs. Por lo tanto, se obtienen un total de 12 patrones con seis en modo directo (ACHM del mismo signo que la CP) y seis en inverso (ACHM de signo opuesto a la CP), que clasifican el 95,5% de los campos mensuales. Tres CPs describen los casos más frecuentes de inviernoprimavera (período con mayor concentración y expansión del hielo marino) y tres CPs corresponden a verano-otoño (menor concentración y retracción del campo de hielo). La primera y segunda CP representan situaciones de invierno y primavera. La segunda componente está rotada 30° en sentido horario con respecto a la primer componente y ambas presentan anomalías dipolares entre los mares a ambos lados de la península Antártica. Estas dos componentes presentan una recurrencia de aproximadamente 4 años en los que alternativamente el exterior del mar de Weddell tiene condiciones de hielo marino sobre lo normal cuando en el norte del mar de Amundsen las anomalías son negativas y viceversa. La condición más frecuente y con una recurrencia anual de verano-otoño (3ºCP) también es bipolar pero entre el interior del Weddell y la región del Amundsen-Bellingshausen costera por ser la región donde se presenta el hielo en esaépoca del año. Las componentes 4º, 5º y 6º refieren a condiciones de ACHM diferentes y no descriptas en la literatura. Por otra parte, las CPs de verano-otoño, fundamentales para la navegación antártica, muestran un cambio de comportamiento ocurrido a fines de los años 80s, en que los mares de Amundsen y Bellingshausen pasaron de tener mayores a menores concentraciones de hielo marino. La distribución espacial de ACHM durante las fases maduras tanto de El Niño muestra una gran variabilidad entre eventos y en algunos casos tiene comportamiento opuesto para diferentes eventos. Lo mismo ocurre para La Niña. La influencia del ciclo El Niño/Oscilación del Sur es clara solo para el invierno que sigue a la fase madura estival del El Niño o La Niña.

The purpose of this paper is to locate the different regions in Los Andes mountain range on which the behavior of the flows of the involved rivers shows statistical homogeneities, studying also their entailment with sea surface temperature and atmospheric circulation. A corrected correlation linear index is defined and used as a distance measurement in a Principal Component Analysis. The first two Components identify two independent regions that explain the greater variability. These regions include: I) the area from the Neuquén River to the Senguer River and II) the area from the Jachal River to the Colorado River. Region I shows a double maximum regime of flow in winter-spring, whereas Region II is characterized by a maximum in summer. The last one would be closely related to the El Niño / Southern Oscillation patterns. The most relevant differences in the associated circulation to volume extremes of the Regions I and whit respect to the Region II would be: 1) the displacement of the circulation systems towards higher latitudes, 2) the greater relevance of the middle latitude systems, 3) the smaller importance of the systems located on the Drake Passage and 4) the presence at 500 hPa of a smaller longitude stationary waves train that crosses the continent at subtropical latitudes coming from the central Pacific in NW-SE direction.

El presente trabajo se centra en localizar las distintas regiones a lo largo de la Cordillera de los Andes sobre las cuales el comportamiento de los caudales de los ríos involucrados muestran homogeneidades estadísticas, estudiando además su vinculación con las condiciones de Temperatura de la Superficie del Mar y Circulación Atmosférica. Se define un índice lineal de correlación corregido, utilizado como medida de distancia en un Análisis de Componentes Principales. Las primeras dos Componentes permiten identificar dos regiones independientes que explican la mayor variabilidad. Estas regiones abarcan: I) desde el río Neuquén hasta el río Senguer y II) desde el río Jachal hasta el río Colorado. La región I presenta un régimen de doble máximo de caudal en invierno-primavera, mientras que la región II se caracteriza por un máximo en verano. Esta última estaría íntimamente ligada a los patrones del ciclo El Niño / Oscilación Sur. Las diferencias más relevantes de la circulación asociada a los extremos de caudal en la región I con respecto a la II serían: 1) el corrimiento de los sistemas de circulación hacia mayores latitudes, 2) la mayor relevancia de los sistemas de latitudes medias, 3) la menor importancia de los ubicados sobre el Pasaje de Drake y 4) la presencia en altura de un tren de ondas estacionarias de menor longitud que atraviesa el continente por latitudes subtropicales provenientes del Pacífico central en dirección NO-SE.

Brazil is a country of continental dimension with a population of different ethnic backgrounds. Thus, a wide variation in the frequencies of hepatitis C virus (HCV) genotypes is expected to occur. To address this point, 1,688 sequential samples from chronic HCV patients were analyzed. HCV-RNA was amplified by the RT-PCR from blood samples collected from 1995 to 2000 at different laboratories located in different cities from all Brazilian States. Samples were collected in tubes containing a gel separator, centrifuged in the site of collection and sent by express mail in a refrigerated container to Laboratório Bioquímico Jardim Paulista, São Paulo, SP, Brazil. HCV- RNA was extracted from serum and submitted to RT and nested PCR using standard procedures. Nested PCR products were submitted to cycle sequencing reactions without prior purification. Sequences were analyzed for genotype determination and the following frequencies were found: 64.9% (1,095) for genotype 1, 4.6% (78) for genotype 2, 30.2% (510) for genotype 3, 0.2% (3) for genotype 4, and 0.1% (2) for genotype 5. The frequencies of HCV genotypes were statistically different among Brazilian regions (P = 0.00017). In all regions, genotype 1 was the most frequent (51.7 to 74.1%), reaching the highest value in the North; genotype 2 was more prevalent in the Center-West region (11.4%), especially in Mato Grosso State (25.8%), while genotype 3 was more common in the South (43.2%). Genotypes 4 and 5 were rarely found and only in the Southeast, in São Paulo State. The present data indicate the need for careful epidemiological surveys throughout Brazil since knowing the frequency and distribution of the genotypes would provide key information for understanding the spread of HCV.

Hidrolisado de bagaço de cana-de-açúcar contendo uma concentração inicial de ácido acético de 3,5g/L foi utilizado como meio de fermentação para a bioconversão de xilose em xilitol pela levedura Candida guilliermondii FTI 20037. Ácido acético (2,0g/L) foi adicionado ao meio em diferentes tempos de fermentação, com o objetivo de avaliar o efeito deste ácido neste bioprocesso. O maior efeito inibitório deste ácido na bioconversão de xilose em xilitol pela levedura ocorreu quando este foi adicionado ao meio após 12h de fermentação. Nesta condição observou-se uma redução de 23,22% e 11,24%, respectivamente, no consumo de xilose e no crescimento celular em relação à fermentação em que a adição deste ácido ocorreu no tempo inicial de incubação. Como conseqüência do efeito inibitório, observou-se os menores valores de rendimento (0,39g/g) e produtividade (0,22g/L.h) de xilitol, correspondendo a uma redução de 36 e 48%, respectivamente, em relação aos valores obtidos com a adição de ácido acético nos outros tempos de fermentação. Os resultados obtidos permitem concluir que, nas condições experimentais empregadas neste trabalho, o efeito inibitório do ácido acético sobre a bioconversão de xilose em xilitol é dependente do tempo de fermentação em que a adição do ácido foi feita e não apenas de sua concentração no meio.

Sugarcane bagasse hydrolysate (initial acetic acid concentration = 3.5g/L), was used as a fermentation medium for conversion of xylose into xylitol by the yeast Candida guilliermondii FTI 20037. Acetic acid (2.0g/L) was added to the medium at different times of fermentation, with the aim of evaluating its effects on the bioconversion process. The addition of acetic acid to the medium after 12h of fermentation resulted in the strongest inhibition of the yeast metabolism. In this case, the xylose consumption and cell growth were, respectively, 23.22 and 11.24% lower than when acid was added to the medium at the beginning of fermentation. As a consequence of the inhibitory effect, lower values of the xylitol yield (0.39g/g) and productivity (0.22g/L.h) were observed, corresponding to a reduction of 36 and 48%, respectively, in relation to the values obtained with the addition of acetic acid after other fermentation times. The results obtained allowed to conclude that, under the experimental conditions employed in this work, the inhibitory effect of acetic acid on the xylose-xylitol bioconversion depends on the fermentation time when this acid was added, and not only on its concentration in the medium.

As cenouras são as principais fontes de origem vegetal em carotenóides provitamínicos A (a e o b-caroteno) e podem ser transformados em vitamina A dentro do organismo animal. Segundo a Pesquisa de Orçamento Familiar realizada na região Sudeste do Brasil, no grupo de raízes e tubérculos, a cenoura é amplamente consumida. As cenouras minimamente processadas foram acondicionadas em embalagens com atmosferas modificadas de 5% O2/10% CO2 e 21% O2 (ar sintético), e tratadas com radiação ionizante gama, fonte de césio, nas doses de 0,25, 0,50, 0,75 e 1,00kGy. Os produtos após o emprego da radiação foram armazenados em refrigeração de 5°C durante 24 dias. Os diferentes tratamentos da cenoura e o grupo controle foram avaliados através das análises de pH, sólidos solúveis totais (SST), acidez total titulável (ATT) e microbiologia. Os resultados de microbiologia evidenciaram que os produtos tratados com as doses de 0,50, 0,75 e 1,0kGy apresentaram redução de 3 a 4 ciclos logarítmicos na contagem total de mesófilos (CTM) logo após a irradiação e uma vida-útil de 20 dias. Não foram detectados coliformes totais e E. coli até o 24º dia. Os patógenos B. cereus, Salmonella e Estafilococos coagulase positivos em 0,1g do produto, também não foram detectados. As contagens de bactérias láticas mantiveram-se menores que 100UFC/g. O processo de irradiação em baixas doses mostra-se promissor na manutenção da qualidade e apresenta-se como uma medida alternativa na redução de perdas pós-colheita.

Carrots are the mains vegetable sources of carotenoids provitamin A (a and b-carotene) which might be transformed into vitamin A in animal organism. According to the Family Budget Survey (FBS, 1991) carried out in the Brazilian Southeast, within the roots and tubers group, carrots are widely consumed. The minimally processed carrots were packaging with 5% O2/10% CO2 and 21% O2 (sintetic air), and g ionizing radiation treatments was carried out with a 137Cs source, of 0.25, 0.50, 0.75 and 1.0kGy doses. After radiation treatments, the products were stored at 5°C for 24 days. The different treatments and the control group were evaluated by analysing for pH, total soluble solids (TSS), total titratable acidity (TTA) and microbiologycal. It was made clear by the microbiologycal analysis results that the products treated with 0.5, 0.75 and 1.0kGy presented a decrease of 3 to 4 logaritmic cicles in aerobic mesophilic microflora just after irradiation and shelf life of 20 days. Total coliforms and E. coli were not detected until the 24th day. The B. cereus, Salmonella and Stafilococos coagulase positive were also not detected in 0.1g of product. The latic microflora were always below detection 100CFU/g level. The results show that the low dose irradiation process is very promising to maintain the quality of the product, being a good alternative to avoid post harvest losses.