Spatiotemporal Variations in Abundance and Biomass of Planktonic Ciliates Related to Environmental Variables in a Temporal Pond, Argentina

This report describes the structure and seasonal dynamics of ciliated protozoa associated with variations in the physicochemical characteristics of the environment in a temporary pond in the Buenos Aires province, Argentina. Plankton samples were obtained and physicochemical variables measured monthly for two years. A total of 50 planktonic ciliates were recorded. The highest species richness occurred during the pond´s filling and stable-hydric phases. Upon the pond´s desiccation, the number of ciliate species decreased, with the lowest values being recorded in spring; while the highest abundance and biomass were observed before the droughts. Ciliate diversity tended to be higher after droughts but decreased with pond desiccation. Most of the ciliate species were rare and found during the filling periods. Vorticella convallaria, Pelagostrobilidium wilberti, and Coleps hirtus were dominant; Cyclidium glaucoma, Strobilidium caudatum, Pseudochilodonopsis piscatoris, Limnostrombidium viride, L. pelagicum, and Chilodonella sp. were common; and Pelagostrombidium mirabile along with Rhabdostyla sp.?an epibiont on cladocerans?were occasional. The first and the sum of all axes in canonical correspondence analysis explained a significant portion of the ciliate-data variance. The autumn and winter samples grouped together corresponding to the highest conductivities, high precipitations, and low temperatures?properties characterizing the filling and stable-hydric periods. The species were distributed mainly according to conductivity and temperature gradients along the first canonical axis. The structure and temporal dynamics of planktonic ciliates from this temporary pond varied with the changes in physicochemical characteristics of the environment determined by flooding and desiccation.Fil: Kuppers, Gabriela Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología "Dr. Raúl A. Ringuelet". Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología; ArgentinaFil: Claps, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología "Dr. Raúl A. Ringuelet". Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología; Argentin

Ciliados (Protozoa) de sedimentos secos de una charca temporaria de la Argentina

Temporary ponds represent special environments that are inhabited by organisms adapted to changing environmental conditions. Ciliates are able to survive complete loss of water in these transient habitats through cyst formation. Nevertheless, ciliates from the Neotropical region in general have been poorly studied through the use of modern techniques. The main goal of this study is to describe the ciliates developing in dried sediments of a temporary pond from the Buenos Aires Province, Argentina through samplings that were performed during the period 2003-2005. Soil samples were obtained during drought phases and rewetted in laboratory, in order to establish raw and enriched cultures. Ciliates were then studied both in vivo and after  impregnation with protargol. In this study, we present four new records for Argentina (Gonostomum affine (Stein, 1859) Sterki, 1878, Stylonychia bifaria (Stokes, 1887) Berger, 1999, Pleurotricha lanceolata (Ehrenberg, 1835) Stein, 1859, Meseres  corlissi Petz and Foissner, 1992), one more for South America (Blepharisma americanum (Suzuki, 1954) Hirshfield, Isquith and Bhandary, 1965), and two for the Neotropical Realm (Gonostomum strenuum (Engelmann, 1862) Sterki, 1878, Stylonychia lemnae Ammermann and Schlegel, 1983).Los cuerpos de agua temporarios son ambientes particulares que se encuentran habitados por organismos adaptados a condiciones fl uctuantes. Los ciliados son capaces de sobrevivir a la pérdida completa de agua del ambiente gracias a la formación de estructuras de resistencia. Por otra parte, los ciliados de la región Neotropical han sido poco investigados con técnicas modernas. El objetivo de este estudio es referir los ciliados que se desarrollaron a partir de los sedimentos secos de una charca temporaria de la provincia de Buenos Aires, Argentina, en la que se realizaron muestreos durante el período 2003-2005. Las muestras de suelo fueron obtenidas durante las fases de sequía y luego resuspendidas en el laboratorio para realizar cultivos naturales y enriquecidos. Los ciliados fueron estudiados in vivo y luego de la impregnación argéntica con protargol. En este trabajo se presentan 4 nuevos registros de especies para la fauna de ciliados de la Argentina (Gonostomum affi ne (Stein, 1859) Sterki, 1878, Stylonychia bifaria (Stokes, 1887) Berger, 1999, Pleurotricha lanceolata (Ehrenberg, 1835) Stein, 1859, Meseres corlissi Petz and Foissner, 1992), 1 para América del Sur (Blepharisma americanum (Suzuki, 1954) Hirshfi eld, Isquith and Bhandary, 1965) y 2 para la región Neotropical (Gonostomum strenuum (Engelmann, 1862) Sterki, 1878, Stylonychia lemnae Ammermann and Schlegel, 1983).Fil: Kuppers, Gabriela Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología "Dr. Raúl A. Ringuelet". Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología; ArgentinaFil: Claps, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología "Dr. Raúl A. Ringuelet". Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología; ArgentinaFil: Lopretto, Estela Celia. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

The utility of the consumer from the ancients to the classics

The concept of utility is, together with the one of cost, the most important one in economic theory; all economic theories – except for the one of the producer – consider utility in their substantiation. Utility appears involved in the subjective theory of value, in the theory of imputation, of decision, of welfare and of playing. Due to the signification it possesses, utility has been initially debated by philosophers, theologians, scientists, who have inevitably inserted ethic or religious elements in the definition of the concept. To a great extent, economic problems are also ethic problems and the contradictions and interferences between moral and economy or their interdependencies with other social sciences have been a reason of controversial debates, especially during the last decades. This study is first of all a theoretical one, presenting multiple aspects on the evolution of the utility paradigm in the economic theory – starting with Antiquity and finishing with the classics – also considering the progress generated by its development in the science of Economy.&nbsp

New Valences for the Financial-Accounting System

A new approach to a company’s information systems is needed, if we take into consideration the globalization process of the economy, the intensified competition, the impose of new qualitative demands or the adjustment to new accounting standards. The former accountant is about to be replaced by the „professional employee with accounting information”, who knows very well how to use the domain technologies. The need for clear, correct and significant information has become a must for all the departments of a company and, definitely, this is especially the case for the financial-accounting department, i.e. when we have to come up with solutions for the profitability of the company.financial accounting system, intelligent technology, multiagent systems, mining technology

Process of transition from school-to-work: generator for the initial stage of path dependence in career development

Main achievements: The major objective of the project was accomplished through building life-table of survival analysis (event history analysis or duration analysis or transition analysis) for describing transitions from school-to-work using longitudinal micro-data. It is important to mention that we built a longitudinal data base, using the ECHP data base for all the 8 waves, with the SPSS program. The discrete model’s approach for this transition is described as the process of entering on the labour market, between two moments/points in time. The observed subjects are viewed as a cohort, a homogenous one. The selective final sample included the people over 16 years old who responded to the interviews in all the 8 waves, within the same household and who achieved the highest level of education one year before 1994. So, the entrance point is 1994 and the exit point is represented by the year of obtaining the main activity status – self defined as "working with an employer in paid employment (15+ hours/week)". There are some intermediary results obtained for 10 countries: Belgium, Denmark, France, Ireland, Italy, Greece, Spain, Portugal, Germany (ECHP – from national sources), United Kingdom (ECHP – from national sources). Transition process from school-to-work is described as the distribution of time-to-event variables, where the 'event' is considered ‘to be employed’ (in the conditions already specified) in opposition to the state of not experiencing this event. Additionally, we compared the distribution by levels of a factor variable represented by 'gender'/sex and 'the highest level of general or higher education completed' (stated in ISCED levels). The main results of the study are expressed through: Median Survival Time, Cumulative Proportion Surviving at End of Interval, Probability Density, Hazard Rate - for the aggregate sample and also for the selected countries: Italy, Portugal and Spain. Final remarks: The major objective of the project was accomplished through building life-table of survival analysis (event history analysis or duration analysis or transition analysis) for describing transitions from school-to-work using longitudinal micro-data. But, under this destination we encounter a lot of “traps” and “opportunities” in view to answer to a lot of questions. First set of questions is concentrated to a better understanding of the Life Table Main Results, their interpretation and analysis from the labour market perspective. 1.The cumulative proportion surviving at the end of an interval could be a speed of (still) searching or a speed of (no)allocation? 2. Probability density / probability of experiencing the event of entering on work, during the given year interval, could be an indicator of the absorbent power of the labour market for the new entrants? 3. Could we consider the hazard rate as a way to measure the “permeability characteristic” of the “local” labour market? Second set of questions is strongly connected with some visible consequences of the duration measuring and analysis in perspective of shaping of the working life span. The median period of this transition process or the average searching period regarded as a measure of searching duration could be a starting point to determine: 1. The “average age” of entrance on the labour market; 2. Discussion regarding the age borders for the young people’s definition. We consider that our enterprise was concentrated to find new semantics for the main results obtained through Life Table Analysis, useful for better explaining the functioning and the characteristics of the labour markets at different levels (national, local and regional). The idea of the journey from learning-to-know to learning-to-do represents a complex set of interactions between the individual/person/young and: o itself, in the sense of making a lot of choices (intending to get employment under the personal strategy); o the socio-economic environment, regarded in this article particularly as the labour market space (described under the absorptive, permeability and speed of allocation characteristics for the new entrants); o unknown, in the sense of the efficient utilisation of all the resources under the new circumstances … We tried to answer the questions and present our study results in this paper. For the moment: “that’s it”, even if the various analyses could continue and we suppose having made misinterpretations/inaccuracies/mistakes; we are expecting readers’ comments in order to correct them. The only reliable conclusion is that the Life Table Analysis could represent a useful tool/instrument to better understand and explain the differences in functioning and for better shaping the characteristics of the labour markets.Demand and Supply of Labo ; Labour Force and Employme ; Time Allocation and Labou ; Labour Demand ; Human Capital; Skills; Oc

Informes Contables de Responsabilidad Social Empresaria.

El siguiente trabajo se refiere a las características de los informes contables microsociales externos e internos y sus beneficios. Su función es de suma importancia ya que permite mostrar a los distintos interesados, la gestión social del ente y a partir de allí tomar sus decisiones

Atención odontológica en niños en etapa de desarrollo temprano (0 a 3 años)

Teniendo en cuenta que los primeros años de vida del niño es un periodo primordial para la constitución del ser, se considera que es necesario contar con profesionales odontólogos capacitados y concientizados en la atención en desarrollo infantil temprano con el fin de lograr la prevención y detección temprana de alteraciones afectivas, motrices, cognitivas y relacionales. Los conceptos de organizadores del desarrollo se constituyen así en un instrumento de base para construír un buen abordaje odontopediátrico, con el objetivo de establecer pautas de atención productivas y menos traumáticas para el niño.Considering that the first period in the life of a child is the most important for his / her development, it is considered to have trained professionals for the dental care of kids from 0 to 3 years old. They should also be aware of the special attention that children need during their development stage in order to prevent and detect the affective, motor, cognitive and relational alterations. The concepts of “development organizers" are constituted as a basic instrument to build a useful odontopediatric approach. Therefore, it is considered to establish more productive and less traumatic treatment patterns for the child.Fil: Suárez, Cristina Gabriela. Universidad Nacional de Cuyo. Facultad de Odontologí

Irisin evokes bradycardia by activating cardiac-projecting neurons of nucleus ambiguus.

Irisin is a newly identified hormone induced in muscle and adipose tissues by physical activity. This protein and its encoding gene have been identified in the brain; in addition, the precursor for irisin, FNDC5, can cross the blood-brain barrier. The fact that irisin is secreted during exercise together with the lower resting heart rate in athletes prompted us to investigate the effect of irisin on cardiac-projecting vagal neurons of nucleus ambiguus, a key regulatory site of heart rate. In vitro experiments in cultured nucleus ambiguus neurons indicate that irisin activates these neurons, inducing an increase in cytosolic Ca(2+) concentration and neuronal depolarization. In vivo microinjection of irisin into the nucleus ambiguus promotes bradycardia in conscious rats. Our study is the first to report the effects of irisin on the neurons controlling the cardiac vagal tone and to link a myokine to a cardioprotective role, by modulating central cardiovascular regulation

The postmodern ethics of global capitalism

Global capitalism constitutes a concept surrounded by contention and controversy, fact which is evidenced by the abundance of studies regarding it, and probably the main feature which is nowadays questioned is its moral behaviour. The present study intends to provide an opposite explanation regarding the ethics of global capitalism by associating it with the contemporary movement of post-modernity. The aim of this paper is to demonstrate that global capitalism, since it reflects societies’ ethics, cannot be intrinsically good or bad, but morally ambivalent, the determination of global capitalism to be more unprejudiced depending on the willingness of individuals to be moral.                                                                                                     

Diversity of freshwater ciliates (Protista) from Argentina

Diversity of ciliates from freshwater and soil were scarcely investigated in Argentina, in spite of their ecological role in these ecosystems and the huge environmental heterogeneity that can be found in this country. In the present study, we describe the morphology of nine species from a temporary pond in Buenos Aires province, by means of live observations and protargol impregnations. Stentor igneus Ehrenberg, Pseudochilodonopsis piscatoris (Blochmann), Vorticella halophila Stiller, Intranstylum invaginatum Stokes, and Epistylis rotans ?vec were recorded for the first time in Argentina, and in most cases, are new for the Neotropical realm as well. In addition, an updated checklist on freshwater ciliates from Argentina is provided, based on ciliates listed for the Salado River basin in the Buenos Aires province, new findings from Rancho Hambre peat bog pools in Tierra del Fuego province and a pond from Misiones province.Instituto de Limnología "Dr. Raúl A. Ringuelet