Field measurements and modelling of high frequency transients during disconnect switch operations in EHV Substations : Assessment of their effects on Current Transformers

The article describes the complete procedure carried out in order to determine the cause of high levels of gases detected in chromatographic determinations performed in Current Transformers (CT) oil. These analyses of gases are normally included in routine maintenance work. The obtained results could evidence some possible damage in the machine insulation. According to the electrical stresses that Current Transformers are typically subjected to, it was presumed that the cause of the possible damaged could be the high-frequency transients that take place during air disconnect switch operations. Therefore, with the aim of determining the presence of such electrical stress, field measurements were performed. A specially designed measuring system was utilized to accomplish this goal. Taking into account the difficulties normally encountered when measuring currents flowing through Current Transformers to ground, especially in terms of accuracy, it was decided to perform voltage measurements. Then, by determining the real frequency response of the CT in the range of interest, it was possible to achieve such currents by computer simulations. In order to achieve accurate results in the simulations, it was necessary to develop an appropriate electrical model of this type of transformers in the analyzed frequency range. Once the model was carefully adjusted, computer simulations were performed. As a result, both shape and magnitude of such currents were also achieved. Finally, one of the Current Transformers with high levels of gases was taken out of service. Then, it was completely disassembled so as to confirm the suspected damage in the insulation. The results yielded in the inspection of the insulation are commented at the end of this work.Instituto de Investigaciones Tecnológicas para Redes y Equipos Eléctricos (IITREE

Balanç de carboni: els embornals a Catalunya

28 pages, 3 figues, 5 tablesEn aquest capítol es determinen els estocs i els embornals de carboni (C) dels diferents sistemes terrestres i marins. El bosc és el sistema terrestre que manté en estoc més quantitat de carboni per hectàrea, 149,5 Mg Cha−1 (en una proporció vegetació/sòl [v:s] de 60:100). Els prats ocupen la segona posició, amb 121,4 Mg Cha−1 (v:s d ’11:10 0 ), i a continuació trobem els conreus llenyosos i els matollars, amb 104,0 Mg Cha−1 (v:s de 12:100) i 112,1 Mg Cha−1 (v:s de 15:100), respectivament. En la darrera posició, hi ha els conreus herbacis, amb 100,8 Mg Cha−1 (v:s d’1:100). La mar catalana ha anat augmentant l’estoc de carboni des del 1750 fins al 2001, amb un còmput acumulat de 12 Mg Cha−1. Les praderies de fanerògames, que acumulen 330 Mg Cha−1 (en una proporció planta/sediment de 4:100) són molt destacables. Les aigües continentals mantenen 47,9 Mg Cha−1, però una part molt elevada és carboni inorgànic dissolt del sistema carbònic-carbonats, que es calcula que pot ser trenta vegades superior al carboni orgànic. [...]Peer Reviewe

A NOVEL FUSION 5'AFF3/3'BCL2 ORIGINATED FROM A t(2;18)(Q11.2-Q21.33) TRANSLOCATION IN FOLLICULAR LYMPHOMA

Follicular lymphoma is the second most frequent type of non-Hodgkin's lymphoma in adults. The basic molecular defect consists of the t(14;18)(q32;q21) translocation, juxtaposing the B-cell lymphoma protein 2 gene BCL2 to the immunoglobulin heavy chain locus IGH@, and leading to the antiapoptotic BCL2 protein overproduction. Variations in the t(14;18) are rare and can be classified into two categories: (i) simple variants, involving chromosomes 18 and 2, or 22, in which the fusion partner of BCL2 is the light-chain IGK@ or IGL@; (ii) complex variant translocations occurring among chromosomes 14, 18 and other chromosomes. We report a follicular lymphoma case showing BCL2 overexpression, detected by immunohistochemistry and real-time quantitative PCR, consequently to the formation of a novel fusion gene between the 5' of the lymphoid nuclear transcriptional activator gene AFF3 at 2q11.2, and the 3' of BCL2. This case shows evidence, for the first time, of BCL2 overexpression consequently to the fusion of BCL2 to a non-IG partner locus

FRONTEIRAS, TRABALHO E ETNICIDADE

A revista Canoa do Tempo traz a público o dossiê Fronteiras, Trabalho e Etnicidade, com artigos que denotam a complexidade da discussão sobre a ideia de fronteira. Para além do entendimento sumário da categoria, usualmente articulada como linha divisória, há o indicativo do peso dos mundos do trabalho no estabelecimento de suas problemáticas. A Amazônia aparece como espacialidade privilegiada para a articulação de estudos desta natureza, ambientados entre o imaginário da opulência e as agruras de formas coercitivas da lida cotidiana. Ao longo do tempo, a floresta foi atravessada por diversos tipos de deslocamentos de fronteiras, cujos desdobramentos socioeconômicos e demográficos deixaram marcas indeléveis no tecido social de suas cidades, aldeias e rios. Não por acaso, a floresta por tempos pensada no terreno do fantástico perdeu força discursiva sob a sombra do colonialismo interno, quase sempre jungido a interesses capitalistas internacionais. O ethos das mulheres guerreiras que (re)batizou o vale ao gosto do imaginário europeu, teve seus sentidos transformados com as sucessivas devassas e esquadrinhamentos do espaço em busca de riquezas. As fronteiras do paraíso terreal tiveram de ser redimensionadas, restando apenas o invólucro da mensagem edênica, que traduziu a Amazônia como terreno inabitado, disponível e à margem da História. A diversidade de abordagens e aparatos teóricos aqui propostos demonstram a as possibilidades dos temas que abalizam o dossiê. Em tempos monocromáticos, refletir sobre a complexidade do conceito de fronteira vai na contramão de pensamentos que simplificam a realidade. Com isso, objetivamos fomentar ainda mais discussões que levem em conta o caráter movediço e múltiplo das experiências humanas no espaço e no tempo. Boa leitura

Orientación espacial de la atención mediante conceptos temporales

Ponència de la VI Reunión Científica sobre Atención (RECA 6), celebrada a Barcelona, 200

Agricultural soil organic carbon stocks in the north-eastern Iberian Peninsula: Drivers and spatial variability

Estimating soil organic carbon (SOC) stocks under agriculture, assessing the importance of their drivers and understanding the spatial distribution of SOC stocks are crucial to predicting possible future SOC stocks scenarios under climate change conditions and to designing appropriate mitigation and adaptation strategies. This study characterized and modelled SOC stocks at two soil depth intervals, topsoil (0–30 cm) and subsoil (30–100 cm), based on both legacy and recent data from 7245 agricultural soil profiles and using environmental drivers (climate, agricultural practices and soil properties) for agricultural soils in Catalonia (NE Spain). Generalized Least Square (GLS) and Geographical Weighted Regression (GWR) were used as modelling approaches to: (i) assess the main SOC stock drivers and their effects on SOC stocks; (ii) analyse spatial variability of SOC stocks and their relationships with the main drivers; and (iii) predict and map SOC stocks at the regional scale. While topsoil variation of SOC stocks depended mainly on climate, soil texture and agricultural variables, subsoil SOC stocks changes depended mainly on soil attributes such us soil texture, clay content, soil type or depth to bedrock. The GWR model revealed that the relationship between SOC stocks and drivers varied spatially. Finally, the study was only able to predict and map topsoil SOC stocks at the regional scale, because controlling factors of SOC stocks at the subsoil level were largely unavailable for digital mapping. According to the resulting map, the mean SOC stock value for Catalan agriculture at the topsoil level was 4.88 ± 0.89 kg/m2 and the total magnitude of the carbon pool in agricultural soils of Catalonia up to 30 cm reached 47.9 Tg. The present study findings are useful for defining carbon sequestration strategies at the regional scale related with agricultural land use changes and agricultural management practices in a context of climate change

Field measurements and modelling of high frequency transients during disconnect switch operations in EHV Substations : Assessment of their effects on Current Transformers

The article describes the complete procedure carried out in order to determine the cause of high levels of gases detected in chromatographic determinations performed in Current Transformers (CT) oil. These analyses of gases are normally included in routine maintenance work. The obtained results could evidence some possible damage in the machine insulation. According to the electrical stresses that Current Transformers are typically subjected to, it was presumed that the cause of the possible damaged could be the high-frequency transients that take place during air disconnect switch operations. Therefore, with the aim of determining the presence of such electrical stress, field measurements were performed. A specially designed measuring system was utilized to accomplish this goal. Taking into account the difficulties normally encountered when measuring currents flowing through Current Transformers to ground, especially in terms of accuracy, it was decided to perform voltage measurements. Then, by determining the real frequency response of the CT in the range of interest, it was possible to achieve such currents by computer simulations. In order to achieve accurate results in the simulations, it was necessary to develop an appropriate electrical model of this type of transformers in the analyzed frequency range. Once the model was carefully adjusted, computer simulations were performed. As a result, both shape and magnitude of such currents were also achieved. Finally, one of the Current Transformers with high levels of gases was taken out of service. Then, it was completely disassembled so as to confirm the suspected damage in the insulation. The results yielded in the inspection of the insulation are commented at the end of this work.Instituto de Investigaciones Tecnológicas para Redes y Equipos Eléctricos (IITREE

Diversity of Drosophilidae parasitoids in organic raspberry crops in Tafí del Valle (Tucumán), Argentina

Se estudió la diversidad de dípteros drosofílidos y parasitoides asociados, en cultivos orgánicos de frambuesa en Tafí del Valle (Tucumán, Argentina). Frutos próximos a madurez fueron cosechados periódicamente, colocados en bandejas plásticas cubiertas con tela voile y mantenidos 15-20 días a ≈25°C y 60-70% de HR. Además, con aspirador entomológico se colectaron muestras de insectos en frambuesas adheridas a las plantas. De los puparios obtenidos, emergieron machos y hembras de Drosophila spp. y parasitoides de los géneros Ganaspis y Dieucoila (Hymenoptera, Cynipoidea, Figitidae, Ganaspini), también encontrados en las colectas. Ganaspis está citado como parasitoide del género Drosophila pero Dieucoila carece de registro de hospedador. Las identificaciones a nivel de especie están en progreso.The diversity of Drosophilidae and associated parasitoids were studied in organic raspberry crops in Tafí del Valle (Tucumán, Argentina). Fruits were harvested periodically near maturity, placed in plastic trays covered with voile cloth and held 15-20 days at H»25°C and 60- 70% RH. Additionally, insect samples were collected with an entomological aspirator, from berries attached to plants. Drosophila spp. females and males emerged from the puparia obtained, as well as parasitoids of the genera Ganaspis and Dieucoila (Hymenoptera, Cynipoidea, Figitidae, Ganaspini), which were also found in the samples collected with the aspirator. Ganaspis is cited as a parasitoid of the genus Drosophila but Dieucoila lacks host registration. Specieslevel identifications are in progress.Facultad de Ciencias Naturales y MuseoComisión de Investigaciones Científicas de la provincia de Buenos Aire