The Lomagundi-Jatuli carbon isotopic event recorded in the marble of the Tandilia System basement, Río de la Plata Craton, Argentina

The “Lomagundi-Jatuli event” corresponds to the most important δ13C positive anomaly (≥5‰) globally reported in Palaeoproterozoic marine carbonates (between ∼2.30 and 2.06 Ga). In the Tandilia System (Argentina), Río de la Plata Craton, this event was recorded in the basement marble of the San Miguel area. The calcite-diopside marble, hosted by biotite gneiss and intruded by 2.12 Ga garnet-leucogranite, was metamorphosed in amphibolite facies during the Transamazonian Cycle. PAAS-normalised rare-earth elements (REE) and Y for the carbonate rocks are HREE-enriched and display positive Eu and Y anomalies, typical of primary precipitates from a mixed hydrothermal-marine environment carbonate. Additionally, a truly negative Ce anomaly for all the samples indicates that the depositional environment was oxidising. Positive δ13C values ranging from +5.90 to +4.30‰ (V-PDB), and δ18O from +17.45 to +13.84‰ (V-SMOW) were determined in this marble, both gradually decreasing towards the contact with the leucogranites. These values indicate that devolatilization reactions took place during the crystallisation of a wollastonite-vesuvianite-grossular-diopside skarn generated by the leucogranite intrusions into the marble. δ18O values obtained from diopside and calcite crystals, in the marble sectors furthest from the contacts with leucogranite, allowed a 663–623 °C formation temperature to be calculated, considering oxygen in a calcite-diopside geothermometric pair. These temperatures are consistent with the metamorphic degree (amphibolite facies) reached in this portion of the basement. Although the San Miguel marble shows petrographic and mineralogical evidence of regional and contact metamorphism, important geochemical and isotopic characteristics, together with its estimated Palaeoproterozoic age, indicate that the marble protolith was a marine carbonate deposited during the “Lomagundi-Jatuli event”.Fil: Lajoinie, Maria Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Recursos Minerales. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto de Recursos Minerales; ArgentinaFil: Lanfranchini, Mabel Elena. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Recursos Minerales. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto de Recursos Minerales; ArgentinaFil: Recio, C.. Universidad de Salamanca; EspañaFil: Sial, A.N.. Federal University of Pernambuco; BrasilFil: Cingolani, Carlos Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; ArgentinaFil: Ballivian Justiniano, Carlos Alberto. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Recursos Minerales. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto de Recursos Minerales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Etcheverry, Ricardo Oscar. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Recursos Minerales. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto de Recursos Minerales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentin

The collapse of the scallop Euvola ziczac (Linnaeus, 1758) (Bivalvia: Pectinidae) fishery in Brazil: changes in distribution and relative abundance after 23 years of exploitation

No Brasil, uma pesca industrial de arrasto dirigida à vieira Euvola ziczac teve inicio em 1973 e colapsou após 1980, quando foram desembarcadas 8.800 t. Atualmente os desembarques não têm ultrapassado algumas centenas de quilos. Baseado em cruzeiros de prospecção realizados em 1974-1975 e em 1995-1996, este trabalho descreve as alterações nos padrões de distribuição e abundância relativa do recurso e discute a sua situação atual frente ao ordenamento local da pesca demersal de arrasto. Nos anos 70 E.ziczac concentrava-se num grande banco localizado entre o sul de São Paulo e o norte de Santa Catarina e entre 30 e 50 metros de profundidade. Tal padrão foi profundamente modificado nos anos 90 quando somente duas pequenas agregações muito pouco densas foram encontradas. Os efeitos cumulativos da redução da área de ocorrência e das densidades do recurso sugerem que a sua biomassa foi reduzida em 98%. O enfoque do manejo da pesca industrial de arrasto da região tem se mantido sobre seu antigo recurso-alvo (o camarão-rosa, Farfantepenaeus paulensis e F. brasiliensis), e medidas adicionais não têm sido implementadas, mesmo depois da frota ter redirecionado seu esforço para recursos alternativos da plataforma continental e do talude. Desta forma a situação da vieira E. ziczac fornece um exemplo concreto dos danos irreversíveis que o redirecionamento do esforço pesqueiro não controlado pode ocasionar sobre os estoques, e demonstra a necessidade de mudança no enfoque do manejo da pesca demersal brasileira.In Brazil, an industrial trawling fishery directed to Euvola ziczac started in 1973 and collapsed after 1980, when scallop landings reached 8,800 t. Since 1995 E. ziczac landings have not surpassed a few hundred kilograms. Based on surveys carried out in 1974-1975 and in 1995-1996, this work assesses temporal changes occurred in scallop distribution and relative abundance patterns and analyzes the current stock situation under the present management regimes applied to the local demersal trawling fishery. In the 1970's E. ziczac was concentrated in a main bed extending from southern São Paulo to northern Santa Catarina States and between 30 and 50 m depth. This pattern changed dramatically during the 1990's, when only two very small and low-density concentrations were found in the region. Cumulative effects of reducing areas and density within the remnant concentrations produced a reduction in the stock biomass of 98%. Management of the local double rig trawler fishery has always focused on its first main target, the shrimps Farfantepenaeus paulensis and F. brasiliensis. Additional measures have not been implemented, even after substantial part of the fleet has directed its effort to alternative shelf and slope resources. The collapse of the Brazilian scallop fishery provides a striking example of irreversible damage caused by uncontrolled fishing redirection allocated to other resources, demonstrating the need of changes in the Brazilian demersal fishery management model

Realidad virtual en la educación: Matemáticas en tercer grado de primaria

Se cumplió con el objetivo señalado en este trabajo de tesis que fue desarrollar una aplicación de RV funcional enfocada al tema de fracciones, que se imparte durante el proceso de enseñanza – aprendizaje a los alumnos de tercer grado de primaria, en México como complemento de las herramientas educativas tradicionales.En la actualidad la tecnología se ha convertido en una herramienta de gran importancia para el ser humano, siendo útil para muchas actividades cotidianas, desde el entretenimiento hasta las actividades laborales. Por ejemplo, en el área educativa a pesar de que los libros y apuntes constituyen el soporte de la enseñanza; las computadoras personales, los Smartphone, las tabletas electrónicas y el internet se están empleando para facilitar la docencia de los profesores y el aprendizaje de los estudiantes, incluyéndose de esta manera en el entorno educativo

Elementos del desarrollo local y recursos disponibles para el desarrollo del turismo alternativo en Ocuilan, México

La complejidad ambiental, enmarcada por la interrelación entre los procesos sociales y territoriales, constituye un argumento central para la delineación de estrategias que promuevan el desarrollo local acorde a las especificidades físicas y socioculturales. Para ello, la planificación territorial deberá avanzar en la adecuada integración de los diferentes recursos que conforman un espacio determinado, con la finalidad de impulsar el equilibrio entre la conservación, adecuado aprovechamiento de los recursos y el mejoramiento en las condiciones de vida de la población local, como una condición necesaria para alcanzar la justicia y el uso racional de los recursos presentes (Mantero, 2004). En este sentido, el aprovechamiento recreativo de los recursos naturales y culturales, puede ser considerado una alternativa económica y para la conservación ambiental, en espacios rurales que enfrentan profundas problemáticas ambientales, a partir del desplazamiento de corrientes de visitantes, atraídos por los elementos biofísicos, las manifestaciones de arte, técnica, folklore, hitos de la historia entre otros elementos culturales, tangibles e intangibles (Rivero, 2001).En México existen numerosas localidades rurales donde el turismo podría constituirse en un eje estratégico para el desarrollo local. Tal es el caso de Ocuilan en el Estado de México donde a partir del aprovechamiento recreativo de sus recursos, se podría estimular la dinamización económica y la conservación ambiental de la región. Para que este turismo alternativo se consolide y pueda contribuir al desarrollo local es preciso instrumentar procesos de planificación territorial que favorezcan el aprovechamiento recreativo del medio natural y los elementos culturales, satisfagan las expectativas de los usuarios y mejoren el nivel de vida los residentes. En este trabajo se identificaron los elementos que caracterizan al desarrollo local, los recursos disponibles y los agentes de desarrollo. Con la finalidad de obtener información sobre la percepción del entorno, los recursos naturales y culturales disponibles, y las posibilidades de participación en la oferta de servicios, se aplicó un cuestionario a 139 personas con estancia temporal y transitoria durante los meses de septiembre a diciembre de 2015. Los resultados mostraron una insuficiente infraestructura y equipamiento turístico para dar cobertura a las necesidades de la población, falta de servicios de transporte, y fallas constantes en los servicios de alcantarillado, recolección de residuos, energía eléctrica y telecomunicaciones. Los habitantes indicaron varias ventajas con respecto al turismo, como la mejora de ingresos, generación de empleos y mayor conocimiento de la cultura por parte de los visitantes. La principal conclusión sugiere que en el lugar de estudio existen recursos naturales y culturales con potencial turístico, interés de los actores locales y una afluencia turística considerable en la región, a partir de las cuales se pueden generar estrategias para el turismo alternativo como soporte del desarrollo local

Trade Agreement and Trade Specialization Between Colombia And The EU

The study analyses the relevance of the trade agreement between Colombia and the European Union as a policy that promotes trade between them (export and import flows) and, subsequently, establishes its effectiveness in reducing the trade deficit of the former. Furthermore, the paper analyses the determinants of trade flows between the parties, emphasizing the effect of factor endowment on their bilateral trade. We use a panel data set from 2005 to 2019, wherein the export and import flows between Colombia and the countries of the European Union are considered. The findings indicate that the trade agreement between the two parties has deepened the Colombian trade deficit. Additionally, it is established that the parties share an inter-industry trade pattern based on their factor endowment. Consequently, the Colombian government should consider these findings to reorient its trade policy towards those European Union countries that have an opposite factor endowment

Insoluble soybean polysaccharides: Obtaining and evaluation of their O/W emulsifying properties

The aims of this work were to obtain different samples of insoluble soybean polysaccharides (ISPS) from defatted soy flour and to study their potential application as O/W emulsifier. In this regard, the insoluble residue (okara) resulting from an aqueous extraction (60 °C, pH 9.0), was submitted to an acidic extraction (pH 3.5, 120 °C) without or with a pretreatment (high pressure homogenization or sonication treatment). The insoluble residues of these extractions were dried (oven, 70 °C or vacuum post-treatment with 2-propanol, 40 °C) yielding different ISPS samples. Aqueous dispersions of ISPS samples (1?2% w/w, pH 3 and 7), were used to prepare coarse and fine O/W emulsions. Emulsion stability against creaming and coalescence processes, and the rheological behavior were analyzed. ISPS samples obtained by okara pretreatment and vacuum dried post-treatment with 2-propanol allow to produces emulsions with high values of flocculation degree, increasing the stability of the particle size, and allowing the formation of stronger gel-like emulsions. These pretreatments expose internal sites of the polysaccharide and protein structures, increasing their superficial hydrophobicity and, therefore, allow a strong absorption of the macromolecules at the oil-water interface and/or the formation of external layers, increasing the rigidity of the interfacial film and contributing to the formation of hydrated flocs, Also, these treatments could solubilize certain compounds in okara that would interfere negatively in the formation of the interfacial film. Particularly, sample obtained by high pressures homogenization of the okara presented the best emulsifying properties and it was not significantly affected by variations in the pH of the emulsion. The results of this research work demonstrate a high potential of application of the ISPS samples as O/W emulsifier, under acid and neutral conditions, increasing the added value of an important by-product of the soybean industry.Fil: Porfiri, María Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Investigación en Funcionalidad y Tecnología de Alimentos; ArgentinaFil: Vaccaro, J.. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Investigación en Funcionalidad y Tecnología de Alimentos; ArgentinaFil: Stortz, Carlos Arturo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones en Hidratos de Carbono. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones en Hidratos de Carbono; ArgentinaFil: Navarro, Diego Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones en Hidratos de Carbono. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones en Hidratos de Carbono; ArgentinaFil: Wagner, Jorge Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Investigación en Funcionalidad y Tecnología de Alimentos; ArgentinaFil: Cabezas, Dario Marcelino. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Investigación en Funcionalidad y Tecnología de Alimentos; Argentin

Conflicto ambiental por la distribución y uso del agua en la microcuenca de la quebrada cerro negro durante el periodo comprendido entre los años 1950 al 2016

La vereda Mancilla ha sido escenario de cambios significativos en sus actividades productivas. Por una parte, históricamente se han desarrollado actividades tradicionales de producción agropecuaria, tales como: los sistemas ganaderos tradicionales, cultivos transitorios anuales y los sistemas de agricultura familiar. Los cambios en los sistemas productivos tradicionales se han generado durante los últimos años, siendo las actividades agrícolas intensivas como el caso de la producción de flores bajo invernadero y cultivos de fresa, ganando terreno en las dinámicas productivas de la vereda. Además, los habitantes de la vereda asentados en la microcuenca de la quebrada cerro negro, se abastecen del agua de dicha quebrada a través del acueducto veredal del km 46. Este acueducto se configura como la forma de gestión comunitaria del agua, puesto que en él se constituyen las instituciones capaces de gestionar, administrar y mantener el agua como recurso y fuente de vida de los pobladores.The sidewalk Mancilla has been the scene of significant changes in its productive activities. On the one hand, traditional agricultural production activities have historically been developed, such as: traditional livestock systems, annual transitional crops and family farming systems. The changes in traditional production systems have been generated during the last years, with intensive agricultural activities such as the production of flowers under greenhouse and strawberry cultivation, gaining ground in the productive dynamics of the path. In addition, the inhabitants of the village settled in the micro-basin of the black hill ravine, they are supplied with water of this ravine through the veredal aqueduct of the km 46. This aqueduct is configured like the form of community management of the water, since in him The institutions capable of managing, administering and maintaining water as a resource and source of life for the inhabitants are constituted.Magíster en Desarrollo RuralMaestrí

Management of citrus canker in Argentina, a success story

Citrus canker is an important bacterial disease of citrus in several regions of the world. Strains of Xanthomonas citri type-A (Xc-A) group are the primary pathogen where citrus canker occurs. After Xc-A entered the Northeast of Argentina in 1974, the disease spread rapidly from 1977 to 1980 and then slowed down and remained moving at slow pace until 1990 when it became endemic. Citrus canker was detected in Northwest Argentina in 2002. This paper presents the main steps in the fight of the disease and the management strategies that have been used to control citrus canker at this time. We think the process might be usefull to other countries with the same situation. Results from more than 40 years of research in Northeast (NE) Argentina indicate that we are at the limit of favorable environment for the disease. The severity of citrus canker is greatly affected by the environment and El Niño Southern Oscillation (ENSO) phenomenon which causes cyclic fluctuations on the disease intensity in the NE region. Weather-based logistic regression models adjusted to quantify disease levels in field conditions showed that the environmental effect was strongly modulated by the distance from a windbreak. Production of healthy fruits in citrus canker endemic areas is possible knowing the dynamics of the disease. A voluntary Integrated Plan to Reduce the Risk of Canker has been in place since 1994 and it allows growers to export unsymptomatic, uninfested fresh fruit to countries which are free of the disease and require healthy, pathogen free fruits. The experience from Argentina can be replicated in other countries after appropriate trials.EEA Bella VistaFil: Canteros, Blanca Isabel. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bella Vista; ArgentinaFil: Moschini, Ricardo Carlos. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Clima y Agua; ArgentinaFil: Gochez, Alberto Martín. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bella Vista; Argentin

Strategic Marketing Environment based on Integrated CRM to Foster Competition

After the great wave of ERP (Enterprise Resource Planning) systems implementations, the organizations focus has been turning to CRM (Customer Relationship Management) applications. CRM systems are centered on one to one interactions with customers, they analyse each client trying to identify his or her own characteristics from internal and external data. At the same time, every client interaction is registered, to create a relationship historical data. Intelligent tools like data mining and OLAP using complex algorithms, rules based systems, fuzzy logic and multivariate statistics data analysis will retrieve the best of clients, partners, employees, suppliers and other strategic data to provide the organization with accurate actions for marketing campaigns, better products, excellence of services and decision making, based on the organization ecosystem. This study reviews concepts of CRM, its architecture and integration with ERP, Governance Systems, and Competence Administration, in the current perspective of integrated corporate management systems connected to the internet. In kernel we propose a “intelligence core joystick” where the strategic core supports and decides about resources allocation, negociates and establishes politics and actions to minimize the conflicting forces to get a balance line satisfaction between participants or partners. Our model also contemplates data warehouse, which centralizes separately all the corporate significant data to provide managers with high quality data for the decision making. According to the corporation, this data warehouse can feed others data marts to serve specific departamental areas such as Marketing and Human Management Competences. In addition, to link the participants, organization and processes, there is a intelligent communication infrastructure to simplify and speed actions, to spread organizational culture and relevant information throughout the organization in a symbiotic way