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Antimicrobial properties and chemical composition of eight exotic and indigenous Argentinean essential oils to control American Foulbrood (AFB) were determined. The oils tested were extracted from Artemisia absinthium, Artemisia annua, Lepechinia floribunda, Aloysia polystachya, Verbena officinalis, Wedelia glauca, Satureja odora and Hetherothalamus alienus. The components of the essential oils were identified by SPME-GC/MS analysis. The antimicrobial activity of the oils against Paenibacillus larvae were determined by broth microdilution method. Two-way ANOVA for minimum inhibitory concentrations (MICs) data and minimal bactericide concentrations (MBCs) data, indicated no significant differences between the thirteen P. larvae strains tested and highly significant differences between the oils. The antimicrobial assays showed that the oils of A. absinthium, A. annua and L. floribunda inhibited the bacterial strains at the lowest concentrations tested, MICs and MBCs averages of 393.6 mg/L to 416.7 mg/L and 517.9 mg/L to 624.4 mg/L respectively, indicating the highest inhibitory capacities. Their antimicrobial activities were attributed to the kind and the variation in percentage of the components. α-Thujone (62.3%) was largely predominant in the oil of the A. absinthium meanwhile artemisia ketone (36.3%) and 1,8-cineole (31.5%) constituted the bulk of the oil of A. annua. 1,8-Cineole (27.5%) was also very important in the composition of the oil of L. floribunda, which also possessed camphene (16.6%) and camphor (12.9%). [ABSTRACT FROM AUTHOR]

The article features CONCIENCIA, an all women nonpartisan organization, in Buenos Aires, Argentina. The institution was founded in 1982 by 22 women in Buenos Aires which aims to promote democracy in the country. The group also focuses on the authoritarian rulers wishing them to be mature citizens and make them realize their civic responsibilities as well as their individual rights and convince them the advantages of democratic participation. CONCIENCIA believes that democracy is the most legitimate government system and it must be consolidated and maintained. Moreover, the association's activities and other programs are also presented.

Para evaluar el efecto de las tecnologías de manejo sustentables y de acciones agresivas en sistemas de producción con pastizal natural psamófilo, se comparó la acumulación de materia seca (MS) de un pastizal natural psamófilo (degradado) con la de especies megatérmicas implantadas y se evaluaron las plantas logradas por superficie, así como el desarrollo de las especies megatérmicas, introducidas al final del primer ciclo de crecimiento. Se analizaron siete tratamientos, según el estado del pastizal natural: sin alterar (PN), sometido a quema (Q), quema y roturación (QR) o implantado con pasto llorón (Eragrostis curvula) (PLL), digitaria (Digitaria eriantha) (D), mijo perenne (Panicum coloratum) (Pc ) o mezcla de megatérmicas (M). Se aplicó un diseño en bloques completamente aleatorizados. Se aplicó análisis paramétrico (ANOVA y DLS) y no paramétrico (Kruskal-Wallis). PN, Q y QR presentaron menor producción de MS (15 g MS m-2 como promedio) (P > 0.05) y PLL, mayor producción y altura vegetativa (166.33 g de MS m-2 y 55 cm, P < 0.05). D manifestó baja densidad de plantas (1.67 m-2), pero también mayor eficiencia de implantación (1.35 %), dado el menor número de semillas viables sembradas (123 m ). Para la densidad de siembra y calidad de semilla utilizada, el mayor número de plantas logrado con PLL (8.42 m-2, P < 0.05) ubicó a esta especie en una posición de ventaja con respecto a las otras. Se recomienda evitar la quema o quema y roturación del pastizal natural degradado, y reemplazarlo con gramíneas perennes megatérmicas, como el pasto llorón. [ABSTRACT FROM AUTHOR]

The volcano Copahue, Neuquén province, Argentina has shown infrequent explosive eruptions since the 18th century. Recently, eruptive activity and seismicity were registered in the period July-October, 2000. As a consequence, ash clouds were dispersed by winds and affected Caviahue village located at about 9 km east of the volcano. Samples of deposited particles from this area were collected during this episode for their chemical analysis to determine elements of concern with respect to the health of the local population and its environment. Different techniques were used to evaluate the distribution of elements in four particle size ranges from 36 to 300 microm. X-ray powder diffraction (XRD) was selected to detect major components namely, minerals, silicate glass, fragments of rocks and sulfurs. Major and minor elements (Al, Ca, Cl, Fe, K, Mg, Mn, Na, S, Si and Ti), were detected by energy dispersive X ray analysis (EDAX). Trace element (As, Cd, Cr, Cu, Hg, Ni, Pb, Sb, U, V and Zn) content was quantified by inductively coupled plasma-mass spectrometry (ICP-MS). Nuclear activation analysis (NAA) was employed for the determination of Ce, Co, Cs, Eu, Hf, La, Lu, Rb, Sc, Sm, Ta and Yb. An enrichment was observed in the smallest size fraction of volcanic ashes for four elements (As, Cd, Cu and Sb) of particular interest from the environmental and human health point of view.