46 research outputs found
Análisis del sepulcro de Quinto Sulpicio Máximo, el niño poeta
Trabajo de fin de Grado. Grado en Filología Clásica. Curso académico 2021-2022Análisis del sepulcro de Quinto Sulpicio Máximo, un niño poeta falllecido a los 11 años de edad. Participó en un concurso literario con una epopeya. El monumento que se le dedica permite tratar cuestiones relacionadas con el status social de su familia, el bilingüismo, el sistema escolar en que se educó y los concursos literarios en la Antigua Roma.Analysis on the tomb of Quintus Sulpicius Maximus, a boy poet who died at the age of 11. He participated in a literary competition. His funerary monument allows dealing with issues related to the social status of his family, bilingualism, the school system in which he was educated and literary contests in ancient Rome
Multilevel current source inverter to improve power quality in a distribution network
This paper deals with the problem of reactive power and harmonics in a standard medium voltage (MV) distribution network. It presents the design of a shunt active filter implemented with a multilevel current source inverter (MCSI) connected to the medium voltage level of a power distribution system. The proposed MCSI is made by identical modules where all inductors carry the same amount of current. The current balance is achieved by a Phase-Shifted Carrier SPWM proper implementation. The performance of proposed active filter is thoroughly simulated with Matlab Simulink. It shows very good behavior in steady state and transient conditions.Instituto de Investigaciones Tecnológicas para Redes y Equipos Eléctricos (IITREE
Pollination and sexual reproduction of key dominant trees of Arid Chaco under different land-use intensities
Fruit production by dominant native trees in the arid Chaco of central Argentina represents a crucial provisioning ecosystem service for local peasant economies. This region presents gradients of different woody vegetation cover (open forests and shrublands) along with cattle production systems operating under a variety of management regimens and socio-environmental degradation conditions. Here, we assess land-use intensity effects on pollination and reproduction of Neltuma spp. and Sarcomphalus mistol. The studied species responded differently to land-use intensity. Pollination service and fruit production in the strict self-incompatible Neltuma spp. tended to decrease with increased land-use intensity. In contrast, both pollination and reproduction in S. mistol, which is able to set fruits with geitonogamous pollen, increased in the highest land-use intensity sites (silvopastoral system). In Neltuma spp., the highest values of fodder production (fruit set, fruit mass and total fruit per plant) were found in secondary forests (medium land-use intensity). The positive effects of land-use intensity on the reproduction of S. mistol could be related to the higher visitation frequency observed in these sites, especially from Apis mellifera, but also with the higher amounts of soil nitrates and light availability in these sites. The only two stingless bee species present in the region (Plebeia molesta and P. catamarcensis) played an important role in the reproduction of Neltuma species, increasing fodder production. Our results highlight the complexity of species response to land-use changes and underline the importance of thinking beyond the conservation of species to concentrate on preserving ecological interactions. Many key functional aspects of ecosystems functioning and ecosystem services provision closely depend on plant-animal interactions. Thus, the promotion of local production systems that allows the preservation of not only provision services but also plant-pollinator interactions is crucial to conserve these remaining arid Chaco forests and secure the livelihoods of local communities.Fil: Marquez, Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Carbone, Lucas Manuel. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Chiapero, Ana Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Calviño, Ana Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Ashworth, Lorena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Zamudio, Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Aguilar, Ramiro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentin
The Toxicity Exerted by the Antibiotic Sulfadiazine on the Growth of Soil Bacterial Communities May Increase over Time
The toxicity exerted by the antibiotic sulfadiazine on the growth of soil bacterial communities was studied in two agricultural soils for a period of 100 days. In the short-term (2 days of incubation), the effect of sulfadiazine on bacterial growth was low (no inhibition or inhibition <32% for a dose of 2000 mg·kg−1). However, sulfadiazine toxicity increased with time, achieving values of 40% inhibition, affecting bacterial growth in both soils after 100 days of incubation. These results, which were here observed for the first time for any antibiotic in soil samples, suggest that long-term experiments would be required for performing an adequate antibiotics risk assessment, as short-term experiments may underestimate toxicity effectsThis study has been funded by the Spanish Ministry of Economy and Competitiveness through the projects CGL2015-67333-C2-1-R and -2-R (FEDER Funds), and by Xunta de Galicia via CITACA Strategic Partnership (ED431E 2018/07) and BV1 research group (ED431C 2017/62-GRC). David Fernández Calviño holds a Ramón y Cajal contract (RYC-2016-20411) financed by the Spanish Ministry of Economy Industry and Competitiveness. Vanesa Santás Miguel holds a pre-doctoral fellowship founded by the University of VigoS
Clarithromycin Effect in Microbial Communities
Financiaciado para publicación en acceso aberto: Universidade de Vigo/CISUGA laboratory experiment was carried out to investigate the response of the microbial communities in acid agricultural soils located in the NW Iberian Peninsula to the presence of clarithromycin. Four soils, with different organic C content and similar pH, and seven different concentrations of clarithromycin (0.49, 1.95, 7.81, 31.25, 125, 500 and 2,000 mg kg−1 of soil) were used, and microbial estimates were made after 8 and 42 incubation days. The phospholipid fatty acids (PLFA) technique was used to estimate the total microbial biomass and biomass of specific microbial groups as well as the microbial community structure (PLFA pattern). The microbial biomass (total and specific groups) was different in the four studied soils, the lowest values being exhibited by soils with the lowest organic C. The antibiotic addition showed a positive effect on microbial biomass (total and specific groups), especially at the highest dose; the effect being similar or even more accentuated with time passed after the addition (42 days ≥8 days). Principal component analysis (PCA) of the PLFA data carried out with the whole data set showed that the main determining factors of the microbial structure followed the order: soil > time incubation ≥ antibiotic dose. When the PCA was performed individually for each incubation time, the results indicated that microbial communities of the four soils were different. Likewise, for each soil, different microbial communities were observed depending on antibiotic concentration. The microbial biomass and PLFA pattern data were coincidentally showing that the clarithromycin addition favored fungi and G− bacteria more that bacteria and G+ bacteria; the effect being dose-dependent. Our data (microbial biomass, PLFA pattern) also demonstrated that the effect of clarithromycin addition on microbial communities in these four acid agricultural soils persisted even after 42 incubation days.Xunta de Galicia | Ref. ED481B-2022-081Ministerio de Ciencia, Innovación y Universidades | Ref. RTI2018-099574-B-C21Ministerio de Ciencia, Innovación y Universidades | Ref. RTI2018-099574-B-C22Ministerio de Ciencia, Innovación y Universidades | Ref. FPU21/0420
Filtro activo de modo corriente multinivel para mejorar la calidad de potencia en sistemas de distribución
Este trabajo trata el problema de las armónicas y potencia reactiva en una red de distribución de mediana potencia y cómo solucionarlo mediante la utilización de un filtro activo en derivación realizado a partir de un convertidor multinivel de modo corriente (MCSI). El MCSI propuesto consiste en módulos idénticos, donde cada inductor conduce la misma corriente. El balance de corriente entre los distintos módulos se consigue haciendo uso de la técnica de modulación conocida como Modulación de Ancho de Pulso con Corrimiento de Fase. El correcto funcionamiento del conjunto sistema-convertidor ha sido analizado en profundidad mediante simulacionesInstituto de Investigaciones Tecnológicas para Redes y Equipos Eléctricos (IITREE
Filtro activo de modo corriente multinivel para mejorar la calidad de potencia en sistemas de distribución
Este trabajo trata el problema de las armónicas y potencia reactiva en una red de distribución de mediana potencia y cómo solucionarlo mediante la utilización de un filtro activo en derivación realizado a partir de un convertidor multinivel de modo corriente (MCSI). El MCSI propuesto consiste en módulos idénticos, donde cada inductor conduce la misma corriente. El balance de corriente entre los distintos módulos se consigue haciendo uso de la técnica de modulación conocida como Modulación de Ancho de Pulso con Corrimiento de Fase. El correcto funcionamiento del conjunto sistema-convertidor ha sido analizado en profundidad mediante simulacionesInstituto de Investigaciones Tecnológicas para Redes y Equipos Eléctricos (IITREE
Multilevel current source inverter to improve power quality in a distribution network
This paper deals with the problem of reactive power and harmonics in a standard medium voltage (MV) distribution network. It presents the design of a shunt active filter implemented with a multilevel current source inverter (MCSI) connected to the medium voltage level of a power distribution system. The proposed MCSI is made by identical modules where all inductors carry the same amount of current. The current balance is achieved by a Phase-Shifted Carrier SPWM proper implementation. The performance of proposed active filter is thoroughly simulated with Matlab Simulink. It shows very good behavior in steady state and transient conditions.Instituto de Investigaciones Tecnológicas para Redes y Equipos Eléctricos (IITREE
Estudios citogenéticos y morfo-anatómicos comparativos entre diploides y poliploides de Solanum elaeagnifolium (Solanaceae)
Solanum elaeagnifolium, morfológicamente variable, se multiplica sexual- y asexualmente y es invasora en distintas partes del mundo. Se desconoce su rango de origen y como se propagó fuera de él. En Argentina existen poblaciones naturales diploides, tetraploides y hexaploides. Presenta tres linajes genéticos claramente distanciados, dos en Sudamérica con poblaciones poliploides y un tercero solo con diploides en América del Norte y áreas invadidas. Nuestro objetivo es detectar relaciones entre nivel de ploidía, linaje y procedencia con características morfológicas de las plantas y variables climáticas. Se realizaron preparados cromosómicos y mediciones de caracteres de epidermis, flor y semilla, en individuos 2x, 4x y 6x de diferente linaje y origen geográfico. Se compararon los valores medios obtenidos mediantes tests estadísticos y la similitud global se evaluó mediante análisis multivariados. Resultados: Únicamente número de estomas y masa de semillas resultaron significativamente diferentes entre niveles de ploidía: los tetraploides presentan menor número de estomas y semillas más pesadas. Las restantes variables morfoanatómicas contribuyen a la diferenciación global de los citotipos, aunque las medias no variaron proporcionalmente con el aumento de ploidía. La precipitación media anual contribuye a la discriminación entre citotipos, coincidiendo la distribución occidental de los tetraploides con la diagonal árida en Argentina. Las diferencias en el tetraploide no pueden atribuirse a un efecto de la poliploidización. El patrón global de datos podría explicarse por múltiples orígenes independientes de la poliploidía, plasticidad fenotípica y presiones del ambiente.Fil: Mancini, Miguel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Chiarini, Franco Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Calviño, Ana Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Stiefkens, Laura Beatriz. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; Argentin
Direct toxicity of six antibiotics on soil bacterial communities affected by the addition of bio-adsorbents
Reducing the toxicity caused by antibiotics on bacterial communities in the soil is one of the great challenges of this century. For this, the effectiveness of amending the soil with different bioadsorbents such as crushed mussel shell (CMS), pine bark (PB) and biomass ash (BA), as well as combinations of them (CMS + PB and PB + BA) was studied at different doses (0 g kg−1 to 48 g kg−1). Soil samples were spiked, separately, with increasing doses (0–2000 mg kg−1) of cefuroxime (CMX), amoxicillin (AMX), clarithromycin (CLA), azithromycin (AZI), ciprofloxacin (CIP) and trimethoprim (TMP). Their toxicity on bacterial growth was estimated using the tritium-labeled leucine (3H) incorporation method. Toxicity was observed to behave differently depending on the antibiotic family and bioadsorbent, although in different magnitude and at different doses. The toxicity of β-lactams (AMX and CXM) was reduced by up to 54% when the highest doses of bio-adsorbents were added due to the increase in pH (CMS and BA) and carbon (PB) contribution. Macrolides (CLA and AZI) showed slight toxicity in un-amended soil samples, which increased by up to 65% with the addition of the bio-adsorbents. The toxicity of CIP (a fluoroquinolone) increased with the dose of the bio-adsorbents, reaching up to 20% compared with the control. Finally, the toxicity of TMP (a diaminopyrimidine) slightly increased with the dose of bio-adsorbents. The by-products that increase soil pH are those that showed the highest increases of CLA, AZI, CIP and TMP toxicities. These results could help to prevent/reduce environmental pollution caused by different kinds of antibiotics, selecting the most appropriated bio-adsorbents and doses.Agencia Estatal de Investigación | Ref. RTI2018-099574-B-C21Agencia Estatal de Investigación | Ref. RTI2018-099574-B-C22Ministerio de Economía, Industria y Competitividad | Ref. RYC-2016-20411Xunta de Galicia | Ref. ED481B-2022-081Xunta de Galicia | Ref. ED481A-2021/309Financiado para publicación en acceso aberto: Universidade de Vigo/CISU