Sobre la atribución genérica de la especie 'Cerithium' valeriae de Verneuil & de Lorière, 1868
Cataldo, Cecilia Soledad; Calzada, Sebastián
Se recuerdan y discuten las diferentes asignaciones genéricas de la especie Cerithium valeriae de Verneuil & de Lorière, 1868. Provisionalmente se propone dejar su atribución genérica abierta.; The different generic assignments for Cerithium valeriae are reminded. For the moment, the following assignment is proposed: “Cerithium” valeriae.
Phylogenetic analysis and taxonomic position of section Verrucosa of Panicum and its relationship with taxa of the Sacciolepis–Trichanthecium clade (Poaceae: Panicoideae: Paniceae)
Nicola, Marcela Viviana; Lizarazu, Mabel Angela; Scataglini, María Amalia
The new genus Kellochloa is proposed, on the basis of morphological and molecular characters, to include two North American species of Panicum s.l., previously classified in sect. Verrucosa: P.brachyanthum and P. verrucosum. Both species are annual, with decumbent culms branching divaricately at the lower nodes, and erect culms with terminal and axillary inflorescences. The spikelets are pilose, with lower glume 1/6 to 1/4 the length of the spikelet, upper glume and lower lemma subequal, 3–5-nerved, the lower anthecium reduced to the lower lemma, and upper anthecium indurate, with bicellular microhairs and simple papillae evenly distributed all over the lemma and palea. Molecular phylogenetic studies, analyzing plastid ndhF and rpoA sequences, confirmed that these morphological characters are differential. The phylogenetic position and taxonomic features of the new genus are established and compared with Panicum s.str. and other taxa of the Sacciolepis–Trichanthecium clade. Full synonymies and descriptions, a distribution map, illustrations of both species, and a key are provided. Two new combinations are proposed. In addition, four African ungrouped species of Panicum s.l. were, for the first time, included in the phylogenetic analysis to analyze their relationship with the new genus and its positions in the Sacciolepis–Trichanthecium clade.
Laboratory and field studies to evaluate the potential of an open rearing system of Lysiphlebus testaceipes for the control of Aphis craccivora in Argentina
Zumoffen, Leticia; Tavella, Julia Rita; Signorini, Marcelo; Salvo, Silvia Adriana
The aim of this work was to examine, both in the field and in the laboratory, ecological aspects of selected plant–aphid–parasitoid interactions to evaluate their potential for the open rearing of the parasitoid Lysiphlebus testaceipes (Cresson) (Hymenoptera: Aphidiinae) for the control of Aphis craccivora (Koch) (Hemiptera: Aphididae) in alfalfa agroecosystems. To this end quantitative samplings of parasitoids and aphids were made fortnightly in three alfalfa crop fields and their spontaneously vegetated edges, in Rafaela (Santa Fe, Argentina), during three years (2009–2011). Three sink webs based on L.testaceipes, on a per-year basis, were constructed to assess the strength of the interactions established by aphids and parasitoids, the host ranges of alternative aphid species, and the tendencies in parasitoid host use across years. In the laboratory, emergence rates, parasitism rates, larval and pupal development times, and adult lifespan of L. testaceipes were analyzed by means of choice tests, including the alternative and the target aphid species in the assays. About 84 % of adults of L. testaceipes obtained in the samples came from Aphis nerii (Boyer de Fonscolombe), an innocuous aphid species only associated with plants of the genus Araujia Brotero (Apocynaceae). Based on our results, the system proposed has many features that support its feasibility to be used as an open rearing system of L. testaceipes: unrisky alternative aphid, easy reproduction of the banker plant and similar suitability of innocuous and pest aphid species for the parasitoid to oviposit and complete their development without noticeably preference for specific hosts.
Persistence of plants and pollinators in the face of habitat loss: Insights from trait-based metacommunity models
Astegiano, Julia; Guimarães Jr., Paulo R.; Cheptou, Pierre Olivier; Morais Vidal, Mariana; Mandai, Camila Yumi; Ashworth, Lorena; Massol, François
The loss of natural habitats is one of the main causes of the global decline of biodiversity. Understanding how increasing habitat loss affects ecological processes is critical for mitigating the effects of environmental changes on biodiversity and thus on the supply of ecosystem services by natural habitats. Habitat loss negatively affects pollinator diversity and the pollination service provided by insects, a key ecosystem service supporting the quantity, quality and diversity of crops directly consumed by humans and the sexual reproduction of most flowering plants. By integrating evolutionary relationships among traits that may modulate plant response to habitat loss, the structure of plant ? pollinator interaction networks and metacommunity models, we examine how plant ? pollinator metacommunities might respond to habitat loss. The main predictions of our trait-based metacommunity model are that (1) variation on dispersal ability among plant species may prevent full metacommunity collapse under pollinator loss associated with increasing habitat loss; (2) habitat loss may select for plants with higher dispersal ability and higher autogamous self-pollination, and will typically decrease the incidence of pollination generalist plants; (3) metacommunities that comprise plants with high autonomous self-pollination ability may harbour higher richness of rare plant species when pollinator diversity declines with increased habitat loss. We discuss the implications of our results for the vulnerability of pollination services for biotically pollinated wild plants and crops co-occurring in human-dominated landscapes.
Isotope effect on the superconducting critical temperature of cuprates in the presence of charge order
Greco, Andres Francisco; Zeyher, Roland
Using the large-N limit of the t–J model and also allowing for phonons and the electron–phonon interaction, we study the isotope effect α for coupling constants appropriate for YB2C3O y . We find that α has a minimum at optimal doping and increases strongly (slightly) towards the underdoped (overdoped) region. Using values for the electron–phonon interaction from the local density approximation we get good agreement for α as a function of T c and doping δ with recent experimental data in YB2C3O y . Our results strongly suggest that the large increase of α in the underdoped region is (a) caused by the shift of electronic spectral density from low to high energies associated with a competing phase (in our case a charge density wave) and the formation of a gap, and (b) compatible with the small electron–phonon coupling constants obtained from the local density approximation. We propose a similar explanation for the anomalous behavior of α in Sr-doped La2CuO4 near the doping 1/8.
Transiciones y afinidades biogeográficas
Ferro, Luis Ignacio
Las transiciones biogeográficas involucran el pasaje de una entidad biogeográfica a otra en el espacio terrestre u oceánico del planeta. La naturaleza de las entidades o unidades biogeográficas puede ser variable de acuerdo al énfasis que se haga en la observación de los distintos aspectos de la distribución de la vida sobre la Tierra. Por ejemplo, en ecología del paisaje, las diferentes unidades se definen por homogeneidad estructural y de procesos funcionales (Forman, 1995; Vila Subirós et al., 2006). El ejemplo más gráfico quizás es un mosaico de bosques, pastizales, humedales, cultivos y áreas urbanas. Cada uno de los elementos del paisaje presenta características estructurales, morfológicas y/o de composición específica similares que los agrupan en una categoría dada y los diferencia de los restantes elementos. Sus límites tienen gran importancia funcional en el flujo e intercambio de materiales, energía e información genética; pueden ser sumamente diversos tanto morfológica como funcionalmente y han sido unificados bajo el concepto de bordes ecológicos (Cadenasso et al., 2003).
Pilot Field Trial of the EG95 Vaccine Against Ovine Cystic Echinococcosis in Rio Negro, Argentina: Second Study of Impact
Larrieu, Edmundo Juan; Mujica, Guillermo; Gauci, Charles G.; Vizcaychipi, Katherina; Seleiman, Marcos; Herrero, Eduardo; Labanchi, José Luis; Araya, Daniel; Sepúlveda, Luis; Grizmado, Claudia; Calabro, Arnoldo; Talmon, Gabriel; Poggio, Thelma Veronica; Crowley, Pablo; Cespedes, Graciela; Santillán, Graciela; García Cachau, Mariela; Lamberti, Roberto; Gino, Lilia; Donadeu, Meritxell; Lightowlers, Marshall W.
Cystic echinococcosis (CE) is an important zoonotic disease caused by the cestode parasite Echinococcus granulosus. It occurs in many parts of the world where pastoral activities predominate, including the Rio Negro province of Argentina. Although CE control activities have been undertaken in the western regions of Rio Negro for more than two decades, the disease continues to remain prevalent in both the human and livestock animal populations. Vaccination of animal intermediate hosts of CE with the EG95 vaccine may provide a new opportunity to improve the effectiveness of CE control measures, although data are lacking about field application of the vaccine. Aims: Evaluate the impact of EG95 vaccination in sheep on the transmission of Echinococcus granulosus in a field environment. Methodology: Two trial sites were established in western Rio Negro province within indigenous communities. Vaccination of lambs born into one trial site was introduced and continued for 6 years. Prior to initiation of the trial, and at the end of the trial, the prevalence of CE in sheep was determined by necropsy. Weaned lambs received two injections of EG95 vaccine, approximately one month apart, and a single booster injection one year later. Vaccination was not implemented at the second trial site. A total of 2725 animals were vaccinated in the first year. Animals from this cohort as well as age-matched sheep from the control area were evaluated by necropsy. Key results: Introduction of the vaccine led to a statistically significant in the number and size of hydatid cysts in comparison to the situation prior to the introduction of the vaccine, or compared to CE prevalence in the control area where the vaccine was not applied. The prevalence of infection in the vaccinated area was also significantly reduced by 62% compared to the re-intervention level, being lower than the prevalence seen in the control area, although the difference from the control area after the intervention was not significant possibly due to limitations in the numbers of animals available for necropsy. Conclusions: Vaccination of sheep with the EG95 vaccine provides a valuable new tool which improves the effectiveness of CE control activities. Vaccination was effective even in a difficult, remote environment where only approximately half the lambs born into the communities were fully vaccinated.
T-duality and α′-corrections
Marques, Diego; Nuñez, Carmen Alicia
We construct an O(d, d) invariant universal formulation of the first-order alpha-prime-corrections of the string effective actions involving the dilaton, metric and two-form fields. Two free parameters interpolate between four-derivative terms that are even and odd with respect to a Z 2-parity transformation that changes the sign of the two-form field. The Z 2-symmetric model reproduces the closed bosonic string, and the heterotic string effective action is obtained through a Z 2-parity-breaking choice of parameters. The theory is an extension of the generalized frame formulation of Double Field Theory, in which the gauge transformations are deformed by a first-order generalized Green-Schwarz transformation. This deformation defines a duality covariant gauge principle that requires and fixes the four-derivative terms. We discuss the O(d, d) structure of the theory and the (non-)covariance of the required field redefinitions.
About the role of typical spacer/crosslinker on the design of efficient magnetic biocatalysts based on nanosized magnetite
Nicolás, Paula; Lassalle, Verónica Leticia; Ferreira, María Luján
The immobilization of Candida antarctica lipase B (CALB) was carried out using glutaraldehyde (GLUT) and/or 3-aminopropyl-triethoxisilane (APTS). The aim of this work was to elucidate the role of these crosslinkers/functionalizers on the efficiency of the prepared nanosized catalysts in solvent-free oleic acid esterification.A series of biocatalysts were prepared in presence or absence of GLUT and APTS. The impact of the amount of initial CALB was also explored. An experimental design was utilized to study the variables that maximize biocatalyst activity.A strong dependence of enzymatic activity with the nominal amount of GLUT as well as the final protein/CALB loading was found. Nominal quantity of APTS did not affect catalyst́s activity when used in combination with GLUT. Additional studies demonstrated that stability during storage was mainly dependent on the enzyme loading. The optimum biocatalyst was reused 6 cycles without mass loss. Biocatalyst́s performance decreased with reuse. Mechanisms justifying these results were proposed.The role of GLUT and APTS on stability during storage and on differences between initial enzymatic activity and the performance in the reaction after two months was discussed. The problem of mixed interaction of CALB (covalent bonding plus simple adsorption) was carefully addressed to explain leaching of the lipaseLeaching and stability on storage should be included in the analysis of modifiers impact when support́s modifiers are used. The fresh and stored biocatalyst enzymatic activity has to be addressed looking at the practical aspects of implementation in technological settings.
Manejo de la recreación y el turismo en conservación
Encabo, Matilde; Boschi de Bergallo, Ana Maria; Sanchez, Sandra E.; Torre, María Gabriela; Paz Barreto, Daniel; Andrés, Juan Manuel; Mastrocola, Yusara Isis; Vazquez, Maria Victoria; Cánepa, Luis Homero; Buchiniz, Yanina
Este proyecto de Investigación promueve el cambio de paradigma en el turismo y la recreación en naturaleza. Su objetivo general es desarrollar y evaluar conocimientos, metodologías y procesos científico tecnológicos que aporten al manejo del Turismo y la Recreación sustentable en áreas naturales y áreas naturales protegidas. Se basa en metodologías de la Ecología de la Recreación y el Turismo. aplicadas a la complejidad ecosistémica y territorial como: Limite de Cambio aceptable, Capacidad de carga Turística, Sistema Integral de Evaluación de Impactos a la Biodiversidad - Actividades de Turismo, entre otras. Algunas conclusiones son: Reforzar los aspectos ambientales de la sustentabilidad en el uso público turístico recreativo en naturaleza; Generar metodologías de análisis, evaluación y control con conocimiento científico de la naturaleza; Avanzar en aspectos teórico – prácticos del modelo Recreación y Turismo en Conservación.
Experiencia en la aplicación de la enseñanza de química de sólidos inorgánicos en forma de proyecto corto
Belletti, Gustavo Daniel; Alconchel, Silvia Alejandra
Se describe el desarrollo y puesta en ejecución de una metodología de enseñanza de Química de Sólidos Inorgánicos para alumnos de la carrera de Licenciatura en Química de la FIQ-UNL. Se empleó una estructura centrada en un proyecto corto de investigación sobre un sólido de interés tecnológico. En torno al mismo, los alumnos aprenden los contenidos teóricos-prácticos de una nueva asignatura e incorporan herramientas valiosas para su futuro desempeño profesional
El rol de los ambientes semi- naturales en la abundancia y diversidad de coleópteros edáficos en los viñedos de la Costa de Berisso, Argentina
Paleologos, María Fernanda; Pereyra, Patricia Cecilia; Sarandon, Santiago Javier; Cicchino, Armando Conrado
Los ambientes semi-naturales que rodean los cultivos aseguran el mantenimiento de las funciones ecológicas. Sin embargo, el aumento de la diversidad dentro de las parcelas cultivadas también contribuiría a mejorar las funciones ecológicas en el agroecosistema. Se evaluó la influencia de hábitats semi-naturales en la abundancia, riqueza y diversidad de coleópteros, así como la dominancia relativa de los diferentes grupos funcionales (depredadores, descomponedores, fitófagos). Este estudio se llevó a cabo en dos fincas de vid con diferente composición de la cobertura vegetal: un viñedo con manejo tradicional de tierras bajas e inundables y un "nuevo" viñedo de tierras altas no inundables. Los coleópteros se muestrearon mediante trampas de caída. Se identificaron 24 familias de coleópteros en el sistema de la zona baja y 23 en el de zona alta. El grado de importancia de los ambientes semi-naturales fue marcadamente diferente entre regiones. En el sistema “tradicional”, la abundancia de coleópteros y la abundancia de los grupos tróficos fue mayor en la parcela cultivada que en los ambientes semi-naturales. En el “nuevo” viñedo fueron mayores en ambientes semi-naturales que en la parcela cultivada. Nuestros resultados muestran que el papel de los ambientes semi-naturales, para favorecer la presencia de fauna, depende de sus características ambientales, y de su complejidad vegetal dentro de las parcelas de cultivo.
Exploring food preferences and the limits of feeding flexibility of seed-eating desert birds
Camín, Sergio Ramón; Cueto, Víctor; Lopez de Casenave, Javier Nestor; Marone, Luis
Habitat degradation caused by cattle grazing may be a serious threat for seed-eating birds because theavailability of beneficial seeds usually diminishes in grazed areas. Ecologically plastic species might, however, circumventfood deprivation via changes in foraging behaviour. We studied the limits of feeding flexibility and factors affecting seedpreferences in Zonotrichia capensis, Diuca diuca, and Saltatricula multicolor.We experimentally assessed preferences forseeds of eight grass and eight forb species by using a protocol that combines choice and non-choice trials, and employed adifferent batch of experiments to evaluate some plausible causes of different feeding flexibility. On average, birds consumed45?140% more grass than forb seeds, confirming previous results. Z. capensis preferred several grass and forb seeds, andshowed maximum feeding flexibility. S. multicolor and, to a lesser extent, D. diuca, were grass specialists that preferredlarge and medium-sized grass seeds. The size of forb seeds did not affect preferences. Coat thickness of grass seeds didnot seriously reduce consumption levels. Birds showed low ability to feed on resources characteristic of degradedenvironments (i.e. annual grass seeds). Species-specific differences in behavioural flexibility could be used to predictdietary and numerical responses of seed-eating birds to habitat degradation.
Antimicrobial resistance in thermotolerant Campylobacter isolated from different stages of the poultry meat supply chain in Argentina
Zbrun, María Virginia; Olivero, Carolina Raquel; Romero Scharpen, Analía; Rossler, Eugenia; Soto, Lorena Paola; Astesana, Diego Martín; Blajman, Jesica; Berisvil, Ayelén Patricia; Signorini Porchietto, Marcelo Lisandro; Frizzo, Laureano Sebastian
The objective of this study was to investigate the antimicrobial resistance in thermotolerant Campylobacter spp. isolated from different stages of the poultry meat supply chain in Argentina. Six poultry meat chains were studied from the reproductive farm to the chicken at the retail. Chickens sampled along each food chain were from the same batch. Samples collected were: a) cloacal samples from hens and chickens on the farm, b) chicken carcasses from the slaughterhouse and retail market. Samples obtained were examined for Campylobacter spp. Antimicrobial resistance was evaluated using the disk diffusion method. Almost all isolates were resistant to nalidixic acid (91.2%) and ciprofloxacin (88.2%). A large proportion of thermotolerant Campylobacter isolated from hens and broilers <1wk showed resistance to erythromycin in comparison with the rest of the stages of the poultry meat supply chain (P=0.031). Campylobacter isolated from broilers (both <1wk and >5wk) and carcasses at slaughterhouse and at retail showed a proportion of resistance to ciprofloxacin and enrofloxacin higher than isolates from hens (P=0.015 and P=0.031, respectively). One strain was resistant to all the antibiotics analyzed, and 46.1% of the isolates were resistant to three or more drug classes. Almost 50% of the isolates were resistant to all quinolones tested (ciprofloxacin, nalidixic acid, and enrofloxacin), and 13.2% were resistant to all quinolones and erythromycin. Campylobacter strains isolated from carcasses at retail showed higher resistance to all quinolones than strains isolated from hens (P=0.016). These results reflect an alarming situation with potential serious consequences to the public health.
Controlling Rotavirus-associated diarrhea: Could single-domain antibody fragments make the difference?; Hacia el control de la diarrea por rotavirus A: ¿podrían los nanoanticuerpos VHH marcar la diferencia?
Maffey, Lucía; Vega, Celina Guadalupe; Parreño, Gladys Viviana; Garaicoechea, Lorena Laura
Group A Rotavirus (RVA) remains a leading cause of severe diarrhea and child mortality. The variable domain of camelid heavy chain antibodies (VHH) display potent antigen-binding capacity, have low production costs and are suitable for oral therapies. Two sets of anti-RVA VHHs have been developed: ARP1-ARP3; 2KD1-3B2. Here, we explore the potential of both sets as a prevention strategy complementary to vaccination and a treatment option against RVA-associated diarrhea in endangered populations. Both sets have been expressed in multiple production systems, showing extensive neutralizing capacity against strains of RVA in vitro. They were also tested in the neonatal mouse model with various degrees of success in preventing or treating RVA-induced diarrhea. Interestingly, mitigation of the symptoms was also achieved with freeze-dried ARP1, so that it could be applied in areas where cold chains are difficult to maintain. 3B2 was tested in a pre-clinical trial involving gnotobiotic piglets where it conferred complete protection against RVA-induced diarrhea. ARP1 was used in the first clinical trial for anti-RVA VHHs, successfully reducing stool output in infants with RVA diarrhea, with no detected side effects.
Characterization of the Genetic Diversity of Trachemys dorbigni and Phrynops hilarii
Guidetti, Brenda Yamile; Siroski, Pablo Ariel; Amavet, Patricia Susana
The utilization of RAPD and ISSR molecular markers is proposed to initiate studies of genetic variability in Phrynops hilarii (Chelidae) and Trachemys dorbigni (Emydidae), two species of fresh water turtles distributed in South America. Three primers of RAPD and four of ISSR were selected and the amplified products of these markers were evaluated by electrophoretic runs in agarose and polyacrylamide gels. The levels of heterozygosity, Shannon index and different allele numbers were slightly higher in P. hilarii for both types of markers. Levels of polymorphism were also higher in P. hilarii than T. dorbigni and both were elevated compared to those recorded for other species. The fact that similar results were obtained with both types of markers for all estimates of diversity highlights the usefulness and validity of the RAPD technique. The molecular markers used were found potentially useful for analysing future temporal and spatial distribution of genetic diversity in both species, expanding scales work.
Elementos de respuesta a estrés en el ovario y su implicancia en la fisiopatología ovárica en bovinos.
Amweg, Ayelen Noelia; Salvetti, Natalia Raquel; Rey, Florencia; Ortega, Hugo Hector
En respuesta a varios estresores, la hormonaadrenocorticotrópica estimula la síntesis y secreción de los glucocorticoides,los cuales pueden afectar la reproducción directamente por acción sobre el ejehipotálamo-hipófisis-ovario. En este sentido, es importante destacar que laovulación ha sido descripta como un proceso inflamatorio localizado, donde unasucesión de eventos lleva a la degradación proteolítica de un punto específicode la pared folicular para permitir la salida del ovocito. Por lo tanto, elcortisol liberado a causa del estrés podría actuar a nivel del sitio ovulatorioinhibiendo la ovulación al producir efectos antiinflamatorios locales. Si bienno ha sido demostrado que el ovario sea capaz de producir glucocorticoides denovo, la hormona adrenocorticotrópica, a través de su unión a los receptores demelanocortinas en el ovario bovino, es capaz de estimular la secreción dehormonas esteroides tanto in vivo como in vitro, principalmente la secreción decortisol, y producir cambios en la expresión de las enzimas11β-hidroxiesteroide deshidrogenasas responsables de la activación/inactivacióndel cortisol. Nuestros resultados indican que la hormona adrenocorticotrópicapuede estar implicada en los mecanismos regulatorios relacionados a la funciónovárica asociados con la ovulación, la esteroidogénesis y la fisiopatología dediferentes enfermedades reproductivas en bovinos.
Una "Casa de Piedra" en el sudoeste del Chubut
Perez, Cecilia Beatriz; Castro, Analia; Casanueva, María Laura
El artículo presenta las primeras etapas de excavación del sitio Casa de Piedra de Roselló, una cueva utilizada como habitación hasta el siglo XX. Ubicada en el ecotono estepa-bosque patagónico, cuenta con fuentes de agua cercanas y otros recursos naturales aptos para la habitación humana.
El nazismo como Stimmung: Los textos políticos del joven Emmanuel Levinas
Rossi, Luis Alejandro
El artículo reconstruye la interpretación del nacionalsocialismo derivada de los textos que Emmanuel Levinas publica en 1933 y 1939. En ella hay una primera confrontación con la filosofía de Martin Heidegger, en la medida en que el pensador francés buscó hallar el nexo de sentido que unía al nacionalsocialismo como «paganismo» con la afirmación del ser que creía encontrar en el pensamiento de Heidegger. Se examina la interpretación que hace Levinas de la tradición judeocristiana como opuesta al «paganismo» y qué contenidos atribuye el filósofo francés a esa tradición.
Circulación de información y representaciones del trabajo en el servicio
Gorban, Debora; Tizziani, Ania
El trabajo en el servicio doméstico también transcurre en espacios que trascienden los límites de los domicilios particulares. Si bien a veces se trata de lugares en los que se permanece por poco tiempo, constituyen puntos de encuentro con otras trabajadoras que posibilitan el intercambio de experiencias de trabajo, intercambios en los que circula información sobre la actividad que resulta de un valor central para estas mujeres. Así, la circulación de información se insinúa como un componente de importancia tanto en la configuración de las relaciones de trabajo en las que se insertan las mujeres empleadas en el servicio doméstico, como en las posibilidades de organización colectiva. Sobre la base de un estudio cualitativo, el objetivo de este artículo es indagar en torno de la manera en que esta información afecta la configuración de la relación laboral entre trabajadoras y empleadores/as y en las condiciones de trabajo de las primeras. Para ello, en la primer sección nos centraremos en caracterizar la manera en que se configura el trabajo en el sector en la Argentina y los desafíos que esa configuración plantea a la organización colectiva de las trabajadoras. En un segundo momento, nos centraremos en el análisis de los espacios que habilitan los intercambios entre las empleadas domésticas, el tipo de información que allí circula y la especificidad del rol que cumplen las organizaciones colectivas. Abordaremos, por último, la manera en que esa información es movilizada por las empleadas en sus experiencias cotidianas de trabajo.; Working in the domestic service implies along with the tasks carried out in the particular address of the employer, displaying some others in spaces that extend this particular addresses limits. Although sometimes workers do not spend too much time in these places, they constitute points of contact with other workers, making possible the interchange of work experiences. And in these interchanges there is a circulation of information on the activity that has a central value for these women workers. In this way is that the circulation of information is insinuated not only as a component of importance in the configuration of the relationships in which domestic workers are inserted, but also in their possibilities of collective organization. Based on a qualitative study, the aim of this article is to analyse the way in which this information affects the configuration of the labor relation between workers and their employers and the working conditions of the first. In the first section of the article we will concentrate in how is characterized domestic work in Argentina and the challenges that its configuration raises to the collective organization process of the workers. At a second moment, we will concentrate in the analysis of the spaces that make possible the interaction between domestic workers, the type of information that circulate there and the specificity of the roll that collective organizations accomplished. In the last part we will depict the way in which these workers in their daily work experiences mobilize that information.; L'exercice du travail dans les services domestiques inclut des activités qui débordent les limites du domicile privé des employeurs. Les commerces, les espaces communs des immeubles, les aires de jeux pour enfants constituent des lieux de travail pour les employées domestiques et des espaces de rencontre avec d'autres travailleuses qui rendent possible des échanges sur leurs expériences de travail. La circulation d'information apparaît comme une dimension importante concernant la configuration des relations de travail des femmes qui s'insèrent dans le secteur, ainsi que les possibilités d'organisation collective de cette catégorie de travailleuses. Sur la base d'une étude qualitative, cet article s'interroge sur les effets de la circulation d'information sur la configuration des relations que les employées établissent avec leurs employeurs et sur leurs conditions de travail. Dans la première section, nous cherchons à caractériser ce secteur en Argentine et analyser les défis de l'organisation collective de ces travailleuses. Dans une deuxième section, nous étudions les espaces qui rendent possible les échanges entre les travailleuses, le type d'information qu'y circule et le rôle joué par les organisations syndicales dans ce circuit. Nous analysons, enfin, la manière dont ces informations sont mobilisées par les travailleuses au cours de leurs expériences quotidiennes de travail.