Two widely used methods for soil phosphorus (P) determination are Bray Kurtz 1 (B & K) and Olsen. Argentine regulations (IRAM-SAGyP) for the analysis of extractable P in soils for agricultural diagnostic purposes define that B & K is suitable in slightly acid, non-calcareous and non allophanic soils, while Olsen is best suited for all soils. In the semi-arid pampean region, P extraction was historically carried out by means of B & K, and even today, this test is used, although its generalized use in all soils is under discussion. The objective of this study was to evaluate the relationship of extractable P using B & K and Olsen in different soils of the semi-arid pampean region. The samples were classified considering their pH value, Fieldes Perrott test reaction and calcareous. In all cases, a significant difference was observed between extractable P determined by B & K and Olsen. A significant linear relationship was observed between both P tests methods; although the coefficients of determination (R²) ranged from 0,12 to 0,79. Based on the results obtained, the use of regression equations was not recommended to convert the results of P from one soil test method to the other in the region under study. Therefore, the P test method to use should be defined based on the diagnostic method used for fertilization recommendation. In those cases where the method of diagnosis is not indicated, the national regulation will define the P extraction method to be used according to the pH of the soil, Fieldes Perrott test reaction and calcareous.

Dos métodos ampliamente utilizados para la determinación de fósforo (P) en suelos son Bray Kurtz 1 (B & K) y Olsen. La normativa argentina (IRAM-SAGyP) para el análisis de P extraíble en suelos con fines de diagnóstico agropecuario define que B & K es aplicable a muestras de suelos levemente ácidos, no calcáreos y no alofánicos, mientras que Olsen es aplicable a muestras de todo tipo de suelos. En suelos de la región semiárida pampeana históricamente se realizó la extracción de P mediante B & K, y aun en la actualidad se emplea este método, aunque su utilización generalizada en todos los suelos es motivo de debate. El objetivo de este trabajo fue evaluar la relación del contenido de P extraíble empleando B & K y Olsen en diferentes suelos de la región semiárida pampeana. Las muestras se clasificaron considerando su valor de pH, reacción al test Fieldes Perrott y calcáreo. En todos los casos se observó diferencia significativa entre los métodos B & K y Olsen. Si bien se observó una relación lineal significativa entre ambos métodos, los coeficientes de determinación calculados estuvieron en el rango 0,12 a 0,79. En base a los resultados obtenidos no se recomienda el uso de ecuaciones de regresión para estimar los resultados de P alcanzados por Olsen a partir de los resultados conseguidos por B & K, en los suelos bajo estudio. Más bien, el método de extracción de P debería definirse en función del método de diagnóstico empleado en la recomendación para fertilizar. En aquellos casos donde no se indique el método de diagnóstico, la normativa nacional definirá el método de extracción de P a utilizar de acuerdo al pH del suelo, reacción al test Fieldes Perrott y calcáreo.

Devido à intensa atividade agrícola no rio Uruguai (Sul do Brasil), há potencial para contaminação aquática por agrotóxicos. Há muitos reservatórios para atender a demanda de água de campos de arroz, formando ambientes lênticos. De acordo com estas informações, o objetivo do presente estudo foi mostrar uma análise comparativa de alguns biomarcadores como a peroxidação lipídica (TBARS), glutationa S-transferase (GST), tióis não-protéicos (NPSH), aminoácidos (AA) e teste písceo de micronúcleos (MNE) em Astyanaxjacuhiensis amostrados em ambientes lóticos e lênticos da região do médio rio Uruguai, comparando estações quentes e frias. Oito pesticidas foram encontrados em amostras de água, sendo propoxur a maior concentração encontrada em ambos os ambientes e estações. Peixes da estação quente apresentaram maiores níveis de biomarcadores bioquímicos e peixes da estação fria apresentaram maiores níveis de MNE e AA. TBARS e AA apresentaram maiores níveis nos peixes de rio, enquanto GST, NPSH, MNE e AA apresentaram níveis mais elevados em peixes da represa. Estes ambientes têm características diferentes, com potencial redox, aeração, sedimentação, estrutura trófica, a entrada de agroquímicos e outros que podem afetar as respostas fisiológicas e bioquímicas de peixe contra situação adversa.

Due to intense agricultural activity in the rio Uruguai (South Brazil), there is the potential for aquatic contamination by agrochemicals. In this region, there are many reservoirs to meet the water demand for rice fields, forming lentic environments. In line with this information, the aim of this study was to show a comparative analysis of some biomarkers, such as lipid peroxidation (TBARS), gluthatione S-transferase (GST), non-protein thiols (NPSH), amino acids (AA) and piscine micronucleus tests (MNE) in Astyanax jacuhiensis from lentic and lotic environments in the middle rio Uruguai region, comparing warm and cold seasons. Eight pesticides were found in water samples, with propoxur having the highest concentration found in both environments and seasons. Fish from the warm season showed higher levels of biochemical biomarkers, and fish from the cold season showed higher levels of MNE and AA. TBARS and AA presented higher levels in fish from the river, while GST, NPSH, MNE and AA presented higher levels in fish from dams. These environments have different characteristics in terms of redox potential, aeration, sedimentation, trophic structure, agrochemicals input and others, which may affect the physiological and biochemical responses of fish in against adverse situations.

La Terapia de Estimulación Cognitiva (TEC) es una intervención psicosocial para personas con demencia que ha obtenido buenos resultados en población anglosajona. El objetivo de este estudio fue evaluar la eficacia de la TEC en una muestra de personas chilenas. Participaron 22 pacientes con diagnóstico de Enfermedad de Alzheimer (EA) en fase leve a moderada, pertenecientes a un centro asistencial de la ciudad de Quillota, Chile. Para determinar la eficacia del programa, se definió un diseño experimental mixto 2x2 de medidas repetidas, asignándose aleatoriamente la muestra a dos grupos: intervención (GI) y control (GC). Se establecieron tres dimensiones para evaluar: cognición, calidad de vida y capacidad funcional de la persona con demencia. Posterior a la intervención, el GI presentó una mejoría significativa en sus indicadores de deterioro cognitivo y calidad de vida; por el contrario, el GC no evidenció cambios positivos en ninguna dimensión, empeorando el declive cognitivo. Ninguno de los grupos experimentó cambios significativos en la capacidad funcional. Si bien en la comparación intergrupo no existieron diferencias significativas en ninguna variable, el GI presentó una mejoría sustancial de la función cognitiva, en comparación con el aumento en la progresión del deterioro cognitivo en el GC. Se recomienda que futuras investigaciones contrasten dichos resultados utilizando una muestra más grande de personas con EA.

Cognitive Stimulation Therapy (CST) is a psychosocial intervention for people with dementia that has been successful in Anglo-Saxon population. The aim of this study was to assess the effectiveness of CST in a sample of Chilean elders. The participants were 22 patients diagnosed with Alzheimer's disease (AD) in mild to moderate stage, who were living in a residential care home in the town of Quillota, Chile. In order to determine the effectiveness of the program, an experimental mixed design 2x2 (repeated measures) was employed. The sample was randomly assigned into two groups: intervention group (IG) and control group (CG). Three dimensions were assessed: cognition, quality of life and functional ability. After the intervention, the IG presented a significant improvement in their cognitive function and quality life. In contrast, the CG did not show positive changes in any dimension. In fact, CG showed a worsening in its cognitive deterioration. Both groups did not showed significant changes in functional ability. Even though intergroup comparisons did not yield significant differences, the IG showed an important improvement in cognitive function, compared with an increase in the progression of cognitive impairment in the CG. It is recommended that future research will contrast these results using a larger sample of people with AD.

En el presente trabajo se intenta abordar el concepto de violencia de género a partir de la violencia ejercida contra las mujeres; además de desarrollar la noción de feminicidio en el contexto de la movilización política que surge a partir de la violación seguida de muerte de Sandra Ayala Gamboa ocurrida en la ciudad de La Plata (Argentina) el 16 de febrero de 2007. Dado el caso, la distancia entre teoría y práctica conduce, por un lado, al aislamiento de las feministas académicas y, por otro, al pragmatismo irreflexivo de los grupos y organizaciones feministas. En nuestra opinión, la reflexión crítica y el análisis de las acciones políticas impulsadas deben ser parte de un mismo proceso.

The present paper seeks to address the concept of gender violence from violence against women, also developing the concept of femicide in the context of political mobilization that emerges from the rape and death of Sandra Ayala Gamboa in the city of La Plata (Argentina) on February 16, 2007. On this case, the gap between theory and practice drives on the one hand, to the isolation of academic feminists, and secondly, to a thoughtless pragmatism of the feminist groups and organizations. In our view, critical thinking and analysis of policy actions should be driven as parts of the same process.