In vitro propagation and stoloniferous stem formation of Thelesperma megapotamicum Figueroa, A. C.; Diaz, S.; Palacio, Lorena; Goleniowski, Marta Ester An efficient “in vitro” propagation protocol for Thelesperma megapotamicum (Spreng.) Kuntnze was established. Nodal segments were cultured in vitro with different combination and concentration of growth regulators. Microshoots (60-days) cultured in Murashige and Skoog (MS) with the addition of 4 mg/l 6-benzyl adenine (BA) were used as explants and incubated on a half salt concentrations MS/2 medium supplemented with different combination of indol butyric acid (IBA) and sucrose for 120 days. Explants cultured on a half of Murashige and Skoog salts (MS/2) with the addition of 1,0 mg/L-40 g/L and 1,5mg/L - 30g/L of IBA and sucrose gave shoot number and principal stem length as the control medium with higher stoloniferous stem percentage or development of shoots in stoloniferous stem respectively.

Verbascum thapsus: Antifungal and phytotoxic properties Vogt, Maria Veronica; Cravero, Carolina; Tonn, Carlos Eugenio; Sabini, Liliana Ines; Rosas, Susana Beatriz Verbascum thapsus (Schrophulariaceae) better known as Mullein is a medicinal plant used in the treatment of inflammatory diseases, asthma, spasmodic cough, diarrhea, and other pulmonary problems. The objective of this study was to evaluate the effect of V. thapsus extracts on fungal plant pathogens growth and seed germination. Verbascum thapsus leaves were treated with n-hexane, chloroform, methanol, cold and warm water to obtained the extracts. Antifungal activity was observed mainly in the methanol extract (1000 µg mL-1) against Fusarium graminearum and Macrophomina phaseolina. Furthermore, results show that the hexane, cold and warm aqueous extract favored or had no toxic effect on Lycopersicon esculentum and Triticum aestivum seeds germination and growth, while the chloroform and methanol extracts affected negatively the germination.

Construcción del conocimiento y desarrollo académico en la universidad Garello, Maria Virginia; Rinaudo, María Cristina; Donolo, Danilo Silvio Nos propusimos aportar elementos para una mayor comprensión de los procesos de construcción y aplicación del conocimiento en alumnos universitarios. Para tal fin nos planteamos analizar la naturaleza de las respuestas proporcionadas por alumnos universitarios a dos tareas consecutivas que requerían uso del conocimiento específico de la materia Didáctica. El análisis de los datos mostró las dificultades que los alumnos tienen para transferir y para recontextualizar el conocimiento en situaciones de resolución de problemas, en especial ante problemas abiertos y poco estructurados.; We propose to contribute with elements for a major understanding of the construction and application process of knowledge in university students. In that order we propose to analyze the nature of the answers provided by university pupils on two consecutives task that demand the use of specific knowledge in Didactic. The analysis of the information showed students problems to transfer and provide a new knowledge context in problem resolution situations, especially in view of open and little structured problems.

“In vitro” Hedeoma multiflorum Benth propagation in response to different nutritional conditions Diaz S.; Figueroa A. C.; Palacio, Lorena; Goleniowski, Marta Ester An efficient protocol for in vitro propagation of Hedeoma multiflorum Benth (“Tomillo de las Sierras”) was established. To determine the effect of different medium and plant growth regulators on the growth rates and essential oil production, nodal segments from in vitro 90-days old plantlets were incubated on the following media: 1) SH (Schenk and Hildebrandt); 2) WP (Lloyd and McCown); 3) B5 (Gamborg). All the media studied were supplemented with different combinations and consentrations of growth regulators: naphtaleneacetic acid (NAA) and 6-benzyl adenine (BA). The optimal shoot length and number of nodes of the plantlets, showing no statistical difference, were obtained in WP with the addition of 2.69:0.5 μM, 0.5:0.5 and 2.69:0.05 μM of NAA:BA and in absence of these growth regulators (control). The best multiple shoot medium with no statistical difference, corresponded to SH with the addition of 0.5:2.25 μM and B5 with 0.05:2.25, 0.5:2.25 and 2.69:2.25 μM of NAA:BA. The major essential oil determined by GC/MS, were common in all the plantlets grown in all the media being pulegone (62-64%) , menthone (25-28 %) and isomenthone (2-2,3%).

Roque Zubiate: Las andanzas de un ladrón de ganado en el Septentrión Novohispano (1750-1836); Roque Zubiate: The Adventures of a Cattle Thief in the Septentrión Novohispano (Northern New Spain) (1750-1836) Ortelli, Sara Ines La biografía de Roque Zubiate es una ventana que permite observar el modo de vida de pequeños rancheros y trabajadores del campo; hombres que, además de la dedicación a las tareas rurales, realizaron actividades consideradas ilícitas por las autoridades coloniales, relacionadas con el abigeato, en connivencia con algunos poderosos locales, de quienes eran, además, hombres de confianza. Esta mirada, que enfoca la trayectoria de un hombre que vivió entre la colonia y los primeros años del periodo independiente y analiza el contexto local, cuestiona el paradigma del bandolerismo como explicación a la presencia de este tipo de fenómenos en las sociedades hispanoamericanas.; The biography of Roque Zubiate is a window through which we may observe the way of life of small ranchers and farm workers. In addition to their rural work, these men also engaged in activities deemed illegal by the colonial authorities, connected with rustling and in connivance with certain powerful local people who were, moreover, trusted men. This view, which focuses on the career of a man who lived between the colonial period and the first years of independence, analyses the local context and questions the paradigm of banditry as an explanation of the presence of this kind of phenomenon in Hispano-American societies.

Bactericidal and Hemolytic Activities of Synthetic Peptides Derived from Granulysin Siano, Alvaro Sebastían; Tonarelli, Georgina Guadalupe; Imaz, María Susana; Perín, Juan Carlos; Ruggeri, María Natalia; Lopez, M.; Santi, Maria Noemi; Zerbini, Elsa Virginia Granulysin is a human polypeptide produced by cytolytic cells active against a broad range of microbes. Three peptides covering the regions 25-50 (Gr-1 and Gr-2) and 39-62 (Gr-3) of granulysin were synthesized, and their in vitro activity against Mycobacterium tuberculosis was evaluated. The most active peptide was Gr-1C, containing a disulphide bridge, with Minimal Inhibitory Concentration value of 10.1 μM. In concentrations of up to 50 μM, Gr-1 and Gr2 didn't exceed 30% of hemolysis.

Los niveles glauconíticos de la formación salamanca, Chubut: su efectividad agronómica como fuente alternativa de fertilizante potásico; The glauconitic levels of the Salamanca Formation, Chubut: its agronomic effectiveness as a potassium fertilizer alternative Castro, Liliana Norma; Scasso, Roberto Adrian; Branzini, Agustina; Zubillaga, Marta Susana; Fazio, Ana Maria; Tourn, Selvia M.; Zubillaga, María M. Las secuencias marinas del Maastrichtiano-Paleoceno inferior representadas por la Formación Salamanca y unidades equivalentes, presentan niveles con glauconita que podrían suplir parcialmente las importaciones de potasio para uso en la industria de fertilizantes. La prospección y muestreo se realizó en las nacientes del río Chico, Chubut, donde los espesores de los niveles glauconíticos alcanzan 20 metros. El trabajo se dividió en fases: fase 1, prospección, muestreo y análisis sedimentológicos y químicos de rutina; fase 2a, ensayos de concentración y tratamiento, y fase 2b, ensayos agronómicos donde se compara la efectividad agronómica de las areniscas glauconíticas (GL) con el fertilizante potásico tradicional (KCl). Estos últimos se realizaron en cámara de cultivo, con las fracciones 125 ∝m y 250 ∝m, (2,85 y 2,82 % K2O respectivamente) de GL y con KCl, variando las dosis aplicadas, más una muestra testigo resultando en total 7 tratamientos. A lo largo de las 4 cosechas no se observó un comportamiento diferencial significativo entre GL1, GL2 (125) y el testigo. Ambos tratamientos de GL 250 ∝m presentaron una mayor biomasa acumulada, superando al testigo en un 44 y 60 % respectivamente. Como conclusión, los tratamientos con GL (125) presentaron resultados poco diferenciables del testigo, en tanto que en GL (250) los valores alcanzados superaron a los obtenidos con la fertilización con KCl. Probablemente la mayor participación de feldespato potásico junto a un incremento en la velocidad de lixiviación por riego en la fracción 125 ∝m origine el rendimiento diferencial observado. La gran extensión areal de la Formación Salamanca y la continuidad de los niveles glauconíticos alienta a continuar su evaluación como fertilizante o enmienda.; The Maastrichtian-Early Palaeocene Salamanca Formation and equivalent marine sequences show several glaucony levels, which could be used as a source of potassium and could partially replace current fertilizer requirements met from import. First agronomic assays are shown comparing the efficiency of greensands (GL) with a traditional potassium fertilizer (KCl). Prospection and sampling took place in the heads of Rio Chico to east of Lago Colhué Huapi, Chubut, where glauconitic levels thickness reach to 20m. This research was separated in phases: phase 1, prospection, sampling, and sedimentological and chemical routine analyses, phase 2a, concentration and ore treatment assays, and phase 2b:, agronomic assays. This last phase, was done in culture chamber, with 125 ∝m and 250 ∝m fractions (2,85 and 2,82 % K2O respectively) and KCl. Varying the dose, seven treatments were completed. In successive harvests (four in total) was observed that GL1 and GL2 (125), did not present a significantly differential behavior with the control. Both treatments of GL 250 ∝m showed major accumulated biomass, overcoming the control in 44 and 60 % respectively. As conclusion, better results were obtained by 250 ∝m overcoming even to the KCl fertilization. Probably the major participation of K feldspars in the 125 ∝m and fast leaching of K in this fraction during successive irrigations of soil would originate the minor observed yield. The great areal extension of the Salamanca Formation and the continuity of the glauconitic levels encourage continuing the evaluation as fertilizer or amendment.

Pharmacological approaches to the treatment of tinnitus Elgoyhen, Ana Belen; Langguth, Berthold Tinnitus is the conscious perception of a phantom sound in the absence of an external source. For 1 in 100 of the general population, the condition severely affects quality of life. In spite of the fact that the market for a drug indicated for tinnitus relief is huge, there are still no FDA-approved drugs, and the quest for a tinnitus-targeted compound faces important challenges. A wide variety of drugs have been used off-label to treat tinnitus sufferers, with limited but significant effects in subsets of patients. If the compounds being developed at present by the pharmaceutical industry finally reach the market, they will establish a turning point in the treatment of this pathology.

(1931) Proposal to conserve the name Pertya against Myripnois (Asteraceae, Pertyeae) Freire, Susana Edith Se propone conservar el nombre de Pertya Sch. Bip.  en contra del género monotipico Myripnois Bunge. Se designan ademas,  lectotipos para Pertya scandens (Thunb.) Sch. Bip. (= Erigeron scandens Thunb.) y Myripnois dioica Bunge.

A model for underpotential deposition in the presence of anions Giménez, María Cecilia; Ramirez Pastor, Antonio Jose; Leiva, Ezequiel Pedro M. A simple model to study the effect of on top coadsorption of anions in underpotential deposition is formulated. It considers a lattice-gas model with pair potential interactions between nearest neighbors. As test system, the electrodeposition of silver on gold is studied by means of grand canonical Monte Carlo simulations. The influence of anions on the adsorption isotherms is analyzed. It is found that as the interaction between silver atoms and anions increases, the monolayer adsorbs at more negative chemical potentials. For large interactions between silver atoms and anions, a expanded structure occurs for the silver monolayer. © 2010 American Institute of Physics.

Antiproliferative activity of synthetic naphthoquinones related to lapachol. First synthesis of 5-hydroxylapachol Bonifazi, Evelyn Lucia; Ríos Luci, Carla; Leon, Leticia G.; Burton, Gerardo; Padron, Jose; Misico, Rosana Isabel A series of 5-hydroxy-1,4-naphthoquinones analogues was synthesized from juglone (6) and their antiproliferative activity against a representative panel of six human solid tumor cell lines has been investigated. The 2,5-dihydroxy-3-(3-methylbut-2-enyl)naphthalene-1,4-dione (4) and 2,3-dihydro-5-hydroxy-2-(prop-1-en-2-yl)naphtho[2,3-b]furan-4,9-dione (27) were the most potent antiproliferative agents with GI50 values of 0.42-8.1 and 0.80-2.2 μM, respectively. The results provide insight into the correlation between some structural properties of 5-hydroxynaphthoquinones and their antiproliferative activity.

A cornerstone in the history of hypertension: The seventieth anniversary of the discovery of angiotensin Milei, Jose In 1939, two independent teams, in Buenos Aires and Indianapolis, identified the polypeptide angiotensin. In 1934, Goldblatt et al. demonstrated that partial occlusion of the renal arteries produces hypertension in dogs, and Houssay in 1936 predicted the presence of a humoral mechanism and, with Fasciolo, demonstrated that the ischemic kidneys released a pressor substance that increased the recipient's blood pressure. Later on, Taquini proved that the rise in blood pressure that follows the re-establishment of circulation in kidneys was also produced by a plasmatic substance from the venous blood of acute ischemic kidneys and it was called 'hypertensin'. Then, they proved that it was the result of an enzymatic reaction in which renin was the enzyme and plasma the substrate. At the same time, in 1939, Page et al. postulated that renin activated by plasma becomes vasoactive and the substance was called 'angiotonin'. Page's group began in 1937, with the purification of renin, studying its renal hemodynamic effects. Later on, Page et al. acknowledged in 1943 the enzymatic nature of the system and renamed their so-called renin-activator as renin substrate. Both groups fused the two original names into 'angiotensin' during a meeting at Michigan in 1958, making the 'adventure of the discovery of angiotensin' a reality. © 2010 Italian Federation of Cardiology.

The involvement of transition metal ions on iron-dependent lipid peroxidation Repetto, Marisa Gabriela; Ferrarotti, Nidia Fatima; Boveris, Alberto Antonio The metals iron (Fe) and copper (Cu) are considered trace elements, and the metals cobalt (Co) and nickel (Ni) are known as ultra-trace elements, considering their presence in low to very low quantity in humans. The biologic activity of these transition metals is associated with the presence of unpaired electrons that favor their participation in redox reactions. They are part of important enzymes involved in vital biologic processes. However, these transition metals become toxic to cells when they reach elevated tissue concentrations and produce cellular oxidative damage. Phospholipid liposomes (0.5 mg/ml, phosphatidylcholine (PC)/phosphatidylserine (PS), 60/40) were incubated for 60 min at 37°C with 25 μM of Fe2+ in the absence and in the presence of Cu2+, Co2+, and Ni2+ (0-100 μM) with and without the addition of hydrogen peroxide (H 2O2, 5-50 μM). Iron-dependent lipid peroxidation in PC/PS liposomes was assessed by thiobarbituric acid-reactive substances (TBARS) production. Metal transition ions promoted lipid peroxidation by H 2O2 decomposition and direct homolysis of endogenous hydroperoxides. The Fe2+-H2O2-mediated lipid peroxidation takes place by a pseudo-second order process, and the Cu 2+-mediated process by a pseudo-first order reaction. Co2+ and Ni2+ alone do not induce lipid peroxidation. Nevertheless, when they are combined with Fe2+, Fe2+-H2O 2-mediated lipid peroxidation was stimulated in the presence of Ni2+ and was inhibited in the presence of Co2+. The understanding of the effects of transition metal ions on phospholipids is relevant to the prevention of oxidative damage in biologic systems. © 2009 Springer-Verlag.

Semantics-based Color Assignment in Visualization Larrea, Martin Leonardo; Martig, Sergio R.; Castro, Silvia Mabel The active use and manipulation of visual representations makes many complex and in tensive cognitive tasks feasible. A visual representation is able to convey relationships among many elem ents in parallel and it provides an individual with directly observable memory. A successful visualization allows the user to gain insight into the data, that is, to communicate different aspects of the data in an effective way. Even with today’s visualization systems that give the user a considerable control over the visualization process, it can be difficult to produce an effective visualization. To obtain useful results, a user has to interr ogate the visual ization very precisely. A strategy to improve this situation is to guide the user with the selection of the parameters involved in the visualization. This paper presents the initial effort dedicated to achieve a visualiz ation system that assists the user in the configuration and preparation of the visualization by considering bot h the semantic of the data and the semantic of the stages through all the visualization process. In this article we present a visualization system for file hierarchies where color assignment is made by a reasoning process through the use of an ontology. This work sets the way forward to integrate the visualization process with a reasoning process and configure a visualization based on the reasoner’s results.

Detecting and mapping buried buildings with Ground-Penetrating Radar at an ancient village in northwestern Argentina Bonomo, Nestor Eduardo; Osella, Ana Maria; Ratto, Norma Rosa We describe an archaeo-geophysical investigation performed near the Palo Blanco archaeological site, Catamarca, Argentina. A large area beyond the northern limit of the site was explored with the Ground-Penetrating Radar (GPR) method in order to detect new buildings. The exploration showed signals of mud-walls in a sector that was located relatively far from the previously known buildings. A detailed survey was performed in this sector, and the results showed that the walls belonged to a large dwelling with several rooms. The discovery of this dwelling has considerably extended the size of the site, showing that the dwellings occupied at least twice the originally assumed area. High-density GPR surveys were acquired at different parts of the discovered building in order to resolve complex structures. Interpreted maps of the building were obtained. Different characteristics of the walls were satisfactory determined, in spite of the low contrast of the dielectric constant at their interfaces and the noticeable spatial fluctuations of the signals due to wall collapses.Systematic excavations confirmed the GPR maps providing further relevant information about the characteristics of the walls and the occupational floor, as well as material for radiocarbon analyses. These analyses indicated that the discovered building was occupied until about AD 880. This fact extends 180 years the previously known period for the village, and also for the settlements in the region (formerly, AD 200 to AD 700). The performed investigations moreover confirmed different architectural characteristics assumed for Palo Blanco, related to the internal and external layouts. Interconnection between the rooms without intermediary courtyards seems to indicate a better use of the internal spaces and a more integrated spatial conception in Palo Blanco than in other villages of the region. © 2010 Elsevier Ltd.

Nonequilibrium electronic transport in a one-dimensional Mott insulator Heidrich-Meisner, F.; González, Ignacio; Al-Hassanieh, K.A.; Feiguin, Fabian Marcelo; Rozenberg, Marcelo Javier; Dagotto, Elbio We calculate the nonequilibrium electronic transport properties of a one-dimensional interacting chain at half filling, coupled to noninteracting leads. The interacting chain is initially in a Mott insulator state that is driven out of equilibrium by applying a strong bias voltage between the leads. For bias voltages above a certain threshold we observe the breakdown of the Mott insulator state and the establishment of a steady-state electronic current through the system. Based on extensive time-dependent density-matrix renormalization-group simulations, we show that this steady-state current always has the same functional dependence on voltage, independent of the microscopic details of the model and we relate the value of the threshold to the Lieb-Wu gap. We frame our results in terms of the Landau-Zener dielectric breakdown picture. Finally, we also discuss the real-time evolution of the current, and characterize the current-carrying state resulting from the breakdown of the Mott insulator by computing the double occupancy, the spin structure factor, and the entanglement entropy. © 2010 The American Physical Society.

Linfomas asociados con la infección por el virus de la inmunodeficiencia humana: subtipos histológicos y asociación con los virus de Epstein Barr y Herpes-8.; AIDS related lymphomas: histopathological subtypes and association with Epstein Barr virus and Human Herpes virus type-8 Corti, Marcelo; de Dios Soler, Marcela; Baré, Patricia; Villafañe, Maria F.; de Tezanos Pinto, Miguel; Pérez Bianco, R.; Narbaitz, Marina Los linfomas no Hodgkin (LNH) constituyen la segunda neoplasia definitoria de Sida más frecuente. En el presente trabajo se evaluaron 48 casos de linfomas asociados con la enfermedad debida al virus de la inmunodeficiencia humana (HIV) diagnosticados en la División Histopatología del Instituto de Investigaciones Hematológicas de la Academia Nacional de Medicina. Se incluyeron en la investigación 5 mujeres y 43 hombres con una mediana de edad al momento del diagnóstico de la neoplasia de 37 años. La evaluación morfológica se realizó en cortes coloreados con hematoxilina-eosina, estudio inmunohistoquímico para la detección del virus de Epstein Barr (VEB) en 48/48 casos, y mediante sonda oligonucleotídica biotinilada para la detección del ADN del Herpes virus humano tipo-8 (HHV-8) en 14/14 linfomas plasmoblásticos (LP). Todos fueron linfomas de fenotipo B, con un curso clínico agresivo y enfermedad neoplásica avanzada al momento del diagnóstico. Se pudo demostrar la fuerte asociación del VEB con los linfomas asociados al sida, con frecuencias que variaron según el subtipo histológico: 16/21 (76%) para los linfomas difusos de grandes células; 1/3 casos (33%) de linfomas de Burkitt y 3/4 (75%) en los linfomas primarios del sistema nervioso central. Globalmente, el genoma del VEB se detectó en 20/28 (71%) de las muestras de biopsias de LNH de esta serie. La detección del HHV-8 resultó negativa en los 14 LP. Los linfomas de Hodgkin fueron más frecuentes en varones,18/20 (90%), con un curso clínico agresivo y franco predominio de los subtipos histológicos de peor pronóstico (90% de casos). En estas neoplasias también se comprobó una frecuente asociación patogénica con el VEB (90% de casos).; Non-Hodgkin lymphomas (NHL) of the B-cell type are the second most common neoplasm among patients with human immunodeficiency virus (HIV) infection and AIDS. Here, we evaluated 48 cases of AIDS-related lymphomas (ARL) diagnosed at the Histopathological Division of the Instituto de Investigaciones Hematológicas of the National Academy of Medicine. Five were females and 43 were males with a median of age of 37 years at the time of the diagnosis. Micrometer sections were prepared and stained with hematoxilin-eosin; immunohistochemical examination for the presence of Epstein-Barr virus (EBV) was carried out in 48/48 cases. Additionally, biotinilated oligonucleotides were used to determine the presence of DNA of the Human Herpes virus type-8 (HHV-8) in 14/14 biopsy smears corresponding to plasmablastic lymphomas (PL). All were fenotype B cell lymphomas with an aggressive course and advanced neoplasm disease at the time of diagnosis. Virological findings showed the strong association between EBV and AIDS-related NHL. According to the histopathological subtype, the EBV genome was detected in 16/21 (76%) diffuse large B cell lymphomas, 1/3 Burkitt lymphoma and 3/4 (75%) of primary central nervous system lymphomas. Globally, EBV genome was detected in 20/28 NHL of this series. Detection of HHV-8 was negative in all cases of PL. Hodgkin lymphoma were more frequent in males 18/20 (90%), with an aggressive clinical course and a significant predominance of the subtypes associated with worse prognosis (90% of cases). We detected a significant association between EBV and HL (90% of cases). We consider that all cases of AIDS related lymphomas should be assessed for the presence of EBV because its presence may play a role in the prognosis.

Characterization of the Earwig, Doru lineare , as a Predator of Larvae of the Fall Armyworm, Spodoptera frugiperda : A Functional Response Study Romero Sueldo, Mabel; Bruzzone, Octavio Augusto; Virla, Eduardo Gabriel Spodoptera frugiperda Smith (Lepidoptera: Noctuidae) is considered as the most important pest of maize in almost all tropical America. In Argentina, the earwig Doru lineare Eschscholtz (Dermaptera: Forficulidae) has been observed preying on S. frugiperda egg masses in corn crops, but no data about its potential role as a biocontrol agent of this pest have been provided. The predation efficiency of D. lineare on newly emerged S. frugiperda larva was evaluated through a laboratory functional response study. D. lineare showed type II functional response to S. frugiperda larval density, and disc equation estimations of searching efficiency and handling time were (a) = 0.374 and (t) = 182.9 s, respectively. Earwig satiation occurred at 39.4 S. frugiperda larvae.

Extreme and Exposed Points of Spaces of Integral Polynomials Boyd, Christopher; Lassalle, Silvia Beatriz We show that if E is a real Banach space such that E has the approximation property and such that 1 → n,s, E, then the set of extreme points of the unit ball of PI (nE) is equal to {±φn : φ ∈ E , φ = 1}. Under the additional assumption that E has a countable norming set, we see that the set of exposed points of the unit ball of PI (nE) is also equal to {±φn : φ ∈ E , φ = 1}.

2-Filteredness and The Point of Every Galois Topos Dubuc, Eduardo Julio A connected locally connected topos is a Galois topos if the Galois objects generate the topos. We show that the full subcategory of Galois objects in any connected locally connected topos is an inversely 2-filtered 2-category, and as an application of the construction of 2-filtered bi-limits of topoi, we show that every Galois topos has a point.