Wind induced dispersion and algal growth in shallow lakes

The objectives of this paper are (1) to present experimental measurements of wind induced, vertical dispersion in Lake Brielle, The Netherlands, and (2) to examine the utility of a euphotic—dark zone model for investigation of the effects of dispersion and sedimentation on algal growth and phosphate cycling in shallow lakes. A tracer technique was used to measure dispersion (D) caused by a moderate wind of 4 m/s. The resulting values ranged between 4 and 6 cm2/s and compared well with that predicted from theory. The latter objective was accomplished by comparing the results of a simple, two compartment model with those using a more complex, but more descriptive, finite difference model which accounts for the algal concentration gradient induced by growth, dispersion and sedimentation. Simulations showed good agreement in computation of the average euphotic and dark zone algal concentrations between the two models for D ranging from 0 to 6 cm2/s and for a sedimentation rate constant, Ks, of 0.002 and 0.02 m/h.\ud \ud The results of simulations suggest that rapid algal growth occurs most readily in calm weather when wind induced dispersion in negligible. Dispersion may also influence the rate of particulate phosphate accumulation in the sediment (due to the settling out of algal cells) and the soluble phosphate profile in the overlying water column. Field data is needed to verify the relationship between algal growth and wind induced dispersion

Trasmisión de maternidad y sexo en el programa de higiene mental de 1966 de la UNLP

En este trabajo, se indaga la trasmisión que Mauricio Knobel hizo de la obra de Marie Langer: Maternidad y sexo. Estudio psicoanalítico y psicosomático (1951, reedición 1964), en la cátedra de Higiene Mental a su cargo, materia de quinto año de la Licenciatura en Psicología del Plan de Estudios del año 1958. La obra apareció como fuente bibliográfica, por primera vez en 1964, conservándose igual hasta el programa de 1966. La incorporación de este texto fue parte de un movimiento de inclusión de clásicos argentinos e internacionales. En el presente trabajo se analiza el programa de 1966 ya que incluye la incorporación de Maternidad y sexo así como modificaciones en los trabajos prácticos. Sostenemos que Mauricio Knobel retoma los postulados de Marie Langer en Maternidad y sexo con el posible fin de definir un contexto acerca de la mujer moderna y la maternidad moderna, para poder conceptualizar e intervenir en relación a los conflictos posibles relacionados a la maternidad y la feminidad. Se concluye que la articulación entre mujer moderna y maternidad delimitó un campo amplio de acción para definir lo normal y lo patológico en el desarrollo femenino. Esta articulación suponemos que fue tomada por la asignatura Higiene Mental para brindar herramientas para pensar a la mujer moderna.Facultad de Psicologí

Feminism in acts. Significations about being a woman on the first graduates of psychology (1958-1962)

El presente trabajo forma parte de las investigaciones realizadas en el marco de la Beca CIN: “Los discursos sobre la mujer en la Carrera de Psicología de la U.N.L.P entre 1958 y 1970” (dirigida por la Dra. Mariela González Oddera, período 20192020) dentro del proyecto titulado “Psicología y orden social: controversias teórico-políticas en las intervenciones de la psicología en la Argentina (1900-1990) (dirigido por la Dra. Ana María Talak, período 2017-2020)”. Tiene por objetivo analizar significaciones sobre el ser mujer en egresadas de la primera promoción de la carrera de Licenciatura en Psicología de la Universidad de La Plata (UNLP). Se pondrá el acento tanto en la experiencia como estudiantes, como en relación a las primeras inserciones laborales, que tuvieron lugar durante principios de la década de 1960. Estas experiencias se inscriben en un tiempo previo a la implantación en nuestro país de la praxis feminista de la segunda ola (Dora Barrancos, 2010). No obstante, como daremos cuenta a lo largo del trabajo, las mismas refieren a una trayectoria que desde el presente se pone en diálogo con la matriz de pensamiento que fue instalando el feminismo. Al poner en tensión el discurso de las entrevistadas, se apuntará a reconstruir la trama de sentidos específicos que operaron en este primer tramo de la construcción profesional.Eje temático: Historia de la Psicología. Epistemología y Filosofía de la ciencia.Facultad de Psicologí

Feminism in action

El presente trabajo forma parte de las investigaciones realizadas en el marco de la beca CIN: “Los discursos psicológicos acerca de la mujer en la carrera de Psicología de la UNLP entre 1958 y 1970” (dirigida por Mariela González Oddera, período 2019-2020) dentro del proyecto titulado “Psicología y orden social: controversias teórico-políticas en las intervenciones de la psicología en la Argentina (1900-1990)”.  El objetivo es recoger representaciones sobre el ser mujer en la primera generación de psicólogas y psicólogos. Desde el punto de vista metodológico, se parte del enfoque de la historia crítica y de los aportes de la perspectiva de la historia reciente (Danziger, 1997; Flier, 2014). En esta oportunidad, se toma como material de análisis entrevistas realizadas a dos egresadas de la primera promoción de la carrera de Psicología de la UNLP: Norma Delucca y Mirta Videla. Se utiliza la categoría de “feminismo en acción” para dar cuenta de una nueva significación sobre el ser mujer que no se enlaza directamente con el sostén de un ideario feminista, pero sí con una práctica y un horizonte que brindó a las mujeres posibilidades de proyectarse en lugares legitimados y de poder, históricamente instituidos como masculinos. En este sentido, el discurso de las entrevistadas recupera la relevancia de referentes mujeres, tanto en el ámbito teórico como en el de la gestión institucional, que marcaron un camino fructífero posible en torno al papel de la mujer en las instituciones. En ese discurso se destacan dos figuras: Fernanda Monasterio y Marie Langer.The present work is part of the research carried out in the framework of the CIN scholarship: “Psychological discourses about women in the Psychology degree of the UNLP between 1958 and 1970” (directed by Mariela González Oddera, period 2019-2020) within the project entitled "Psychology and social order: theoretical-political controversies in the interventions of psychology in Argentina (1900-1990)”. The goal is to collect representations about being a woman in the first generation of psychologists. From the methodological point of view, it is based on the critical history approach and the contributions of the recent history perspective (Danziger, 1997; Flier, 2014). On this occasion, interviews with two graduates of the first promotion of the Psychology degree of UNLP: Norma Delucca and Mirta Videla are taken as analysis material. The category of “feminism in action” is used to account for a new significance about being a woman which is not directly connected to the support of a feminist ideology but to a practice and a horizon that gave women possibilities to project themselves in legitimate places of power, historically instituted as masculine. In this sense, the discourse of the interviewees recovers the relevance of women referents, both in the theoretical field and in that of institutional management, which marked a possible fruitful path around the role of women in institutions. Two figures stand out: Fernanda Monasterio and Marie Langer.Facultad de Psicologí

Coordinating Networked Learning Activities with a General-Purpose Interface

Classrooms equipped with wirelessly networked tablets and handhelds can engage students in powerful collaborative learning activities that are otherwise impractical or impossible. However, the system must fulfill certain technological and pedagogical requirements such as tolerance for latecomers, supporting disconnected mode gracefully, robustness across dropped connections, promotion of both positive interdependence and individual accountability, and accommodation of differential rates of task completion. Two approaches to making a Tuple Space-based computer architecture for connectivity into an inviting environment for the generation and creation of novel coordinated activities were attempted. One approach made the technological “bones” of the system very clear but assumed user vision of the complex goals and settings of real education. The more satisfactory approach made clear how Tuple Spaces matches the complex goals and settings of real education, but backgrounded technical complexity. This approach provides users with a system, Group Scribbles, which may inspire a wide range of uses.SRI International Virginia Tech Newport Universit

Partnering for greater success: local stakeholders and research in tropical biology.

Local communities are important stakeholders in resource management and conservation efforts, particularly in the developing world. Although evidence is mixed in suggesting that these resident stakeholders are optimal forest stewards, it is highly unlikely that large tracts of tropical forests will be conserved without engaging local people who depend on them daily for their livelihoods. Stakeholders, who reside in biodiverse ecosystems like tropical forests, are the largest direct users and ultimate decision-makers of forest fate, can be important investors in conservation, harbor local ecological knowledge that complements Western science and frequently have long-term legitimate claims on lands where they reside. Research partnerships with local stakeholders can increase research relevance, enhance knowledge exchange and result in greater conservation success. Different phases of the research cycle present distinct opportunities for partnership, with flexibility in timing, approaches and strategies depending on researcher and local stakeholder needs and interests. Despite being the last step in the research process, dissemination of results can be the best starting point for researchers interested in experimenting with local stakeholder engagement. Still, tropical biologists might not choose to partner with local people because of lack of institutional rewards, insufficient training in stakeholder engagement, insecure research infrastructure in community settings, and time and funding limitations. Although not appropriate in all cases and despite significant challenges, some biological scientists and research institutions have successfully engaged local stakeholders in the research process, proving mutually beneficial for investigators and local people alike and resulting in important innovations in tropical biology and conservation

Comprensión de textos informativos en estudiantes universitarios usuarios de redes sociales

En los últimos años se asiste a un creciente número de investigaciones que indagan cómo el uso de redes sociales impacta en las capacidades desarrolladas por los sujetos para comprender distinto tipos de textos. Sin embargo, no ha sido suficientemente analizado el impacto del uso intensivo de los nuevos medios tecnológicos en las habilidades para realizar una lectura comprensiva. El objetivo del presente trabajo es indagar si existe relación entre la frecuencia e intensidad del uso de redes sociales y el nivel de comprensión lectora de textos informativos en estudiantes universitarios de los primeros años de la Facultad de Psicología de la Universidad Nacional de La Plata (UNLP). Participaron de la investigación 100 sujetos (70 mujeres, 30 hombres), el promedio de edad es de 24 años (de 9.11). Los datos han sido recogidos mediante dos instrumentos: 1) un cuestionario ad-hoc construido con el fin de obtener datos sociodemográficos y el perfil de usuario de redes sociales de los sujetos y 2) una prueba de screening sobre comprensión de textos informativos. El análisis de los resultados permite afirmar que la frecuencia e intensidad con que los sujetos se conectan a las redes sociales no tiene un impacto en la comprensión lectora de textos informativos.In the last years, the studies about social network and their impact on reading comprehension performance have increased. However, the abuse in their use, it has not been studied at all, thus, the main of the present study is determinate if the frequency and intensity in the use of social network have an impact on the reading comprehension performance in university students at the Faculty of Psychology, National University of La Plata. In the research, 100 students have participated (70 female and 30 male), with an average age of 24 years (De 9.11), currently in their first and second year at the University. The data were collected through two instruments: 1) an ad-hoc questionnaire constructed to obtain sociodemographic data and the profile of social networks of the users; and 2) a screening test on comprehension of informative texts. The analysis of the results allows to affirm that the frequency and intensity with which many student use social networks does not have an impact in the reading comprehension of informative texts.Mesa de trabajos libres: Psicología y EducaciónFacultad de Psicologí

Investigation of E. coli and Virus Reductions Using Replicate, Bench-Scale Biosand Filter Columns and Two Filter Media

The biosand filter (BSF) is an intermittently operated, household-scale slow sand filter for which little data are available on the effect of sand composition on treatment performance. Therefore, bench-scale columns were prepared according to the then-current (2006–2007) guidance on BSF design and run in parallel to conduct two microbial challenge experiments of eight-week duration. Triplicate columns were loaded with Accusand silica or crushed granite to compare virus and E. coli reduction performance. Bench-scale experiments provided confirmation that increased schmutzdecke growth, as indicated by decline in filtration rate, is the primary factor causing increased E. coli reductions of up to 5-log10. However, reductions of challenge viruses improved only modestly with increased schmutzdecke growth. Filter media type (Accusand silica vs. crushed granite) did not influence reduction of E. coli bacteria. The granite media without backwashing yielded superior virus reductions when compared to Accusand. However, for columns in which the granite media was first backwashed (to yield a more consistent distribution of grains and remove the finest size fraction), virus reductions were not significantly greater than in columns with Accusand media. It was postulated that a decline in surface area with backwashing decreased the sites and surface area available for virus sorption and/or biofilm growth and thus decreased the extent of virus reduction. Additionally, backwashing caused preferential flow paths and deviation from plug flow; backwashing is not part of standard BSF field preparation and is not recommended for BSF column studies. Overall, virus reductions were modest and did not meet the 5- or 3-log10 World Health Organization performance targets

Design and Calibration of an Organic Diffusive Probe to Extend the Diffusion Gradient Technique to Organic Pollutants

The objective of this study was to develop a method for measuring the mobility of persistent organic pollutants in the solid phase of soils within the context of environmental pollution risk assessment. A new diffusive probe, purposely designed by adapting the diffusive gradient technique method, measures labile organic species by immobilizing them after diffusion through a thin deionized water layer. The measure of the mass accumulated is used to calculate the flow of pollutant from solid phase to pore water. Naphthalene was chosen as a model persistent organic pollutant. The probe was calibrated at different temperatures and was then tested in several microcosms at different porosity and reactivities with naphthalene (one clay soil, two sandy soils and one natural soil). The probe response showed good agreement with the expected different abilities of the solid phases in restoring the solution phase. The concentration of naphthalene in the pore water was well buffered by rapid equilibria with the solid phase in the investigated natural soil. In contrast, pore water concentration in the sandy soils decreased rapidly and the flow was slackened, especially for the sandy soil with finer particles. In clay, only a fraction of the total naphthalene content was present in the labile fraction, while the remaining was tightly bound and was not released to the pore water. Therefore, this first stage of testing points out that the diffusive gradient technique, if optimized, can properly quantify the mobility of organic pollutants in soil