Entre el arte y la técnica: René Villeminot y la arquitectura beaux- arts en la Argentina (1878-1928); Between art and technique: René Villeminot and the beaux-arts architecture in Argentina (1878-1928) Franchino, Magali Debora Solange René Villeminot formó parte de un grupo de personajes relevantes en la construcción del campo disciplinar de la Arquitectura en la Argentina a principios del siglo XX. Más que la construcción de una biografía, el interés de este trabajo se focalizará en el estudio de su esfera artística y profesional, dando cuenta de las particularidades de su producción en el marco del proceso de institucionalización de la Arquitectura como disciplina en los primeros decenios del siglo XX. En este sentido, analizar su trayectoria implica reconocer la complejidad que su figura adquiere al ser uno de los primeros personajes que articula la enseñanza de la Arquitectura, el ejercicio de la profesión dentro de las reparticiones estatales y la construcción de la arquitectura pública del Estado nacional.; René Villeminot was part of a group of prominent f gures in the construction of the architectural discipline in Argentina in the early twentieth century. Rather than a biography, the interest of this work will focus on the study of his artistic and professional sphere, identifying the particularities of his production during the process of institutionalization of Architecture as a discipline in the early decades of the twentieth century. In this direction, analyzing his trajectory involves recognizing the complexity that his figure acquires as one of the first characters that articulates architectural teaching, professional work in the state and the construction of national state public works.

La Política de Manejo de la Tierra Vacante en en Gran La Plata, Buenos Aires; Vacant Land Management Policy in Greater La Plata, Province of Buenos Aires Frediani, Julieta Constanza A partir del reconocimiento del significativo papel que adquiere la tierra vacante en la definición de las políticas de suelo como una instancia básica e indispensable para el desarrollo urbano, el presente trabajo se propone profundizar en esta temática. La reutilización de tierras vacantes a través de adecuadas políticas de manejo permitiría contribuir a la recuperación de la calidad urbana-ambiental de ciudades actualmente dispersas y fragmentadas. Sin embargo, la ausencia de políticas de suelo orientadas a la planificación del desarrollo de las ciudades y a corregir las distorsiones del crecimiento urbano pone de manifesto la relevancia de profundizar en esta problemática. En este contexto, el objetivo general del presente trabajo consiste en contribuir al conocimiento de la relación entre las políticas de suelo y la tierra vacante en el interior de la región del Gran la Plata, tendiente a una utilización del territorio social y ambientalmente sustentable.; Recognizing the significant role that vacant land acquires in the definition of land policies as a basic and essential resource for urban development, this paper proposes the analysis of this dimension. Reuse of vacant land through appropriate management policies would contribute to the recovery of the urban-environmental quality of currently dispersed and fragmented cities. However, the absence of land policies oriented towards planning their development and in order to correct the distortions of urban growth, it is relevant to deepen the understanding of this issue. In this context, the general objective of this study is to contribute to the knowledge of the relationship between land policies and vacant land in the Greater La Plata area, based on the use of socially and environmentally sustainable territory.

Remote sensing and ground-based measurements of evapotranspiration in an extreme cold Patagonian desert Cristiano, Piedad María; Pereyra, Daniel Alberto; Bucci, Sandra Janet; Madanes, Nora; Scholz, Fabian Gustavo; Goldstein, Guillermo Hernan Accurate estimates of seasonal evapotranspiration (ET) at different temporal and spatial scales are essential for understanding the biological and environmental determinants of ecosystem water balance in arid regions and the patterns of water utilization by the vegetation. For this purpose, remote sensing ET estimates of a Patagonian desert in Southern Argentina were verified with field measurements of soil evaporation and plant transpiration using an open top chamber. Root distribution and seasonal variation in soil volumetric water content were also analysed. There was a high correlation between remote sensing and field measurements of ecosystem water fluxes. A substantial amount of the annual ET occurred in spring and early summer (73.4 mm) using winter rain stored in the soil profile and resulting in water content depletion of the upper soil layers. A smaller amount of annual ET was derived from few rainfall events occurring during the mid or late summer (41.4 mm). According to remote sensing, the 92.9% of the mean annual precipitation returns to the atmosphere by transpiration or evaporation from the bare soil and by canopy interception. Only 7.1% infiltrates to soil layers deeper than 200 cm contributing to the water table recharge. Fourier time series analysis, cross-correlation methods and multiple linear regression models were used to analyse 11 years of remote sensing data to assess determinants of water fluxes. A linear model predicts well the variables that drive complex ecosystem processes such as ET. Leaf area index and air temperature were not linearly correlated to ET because of the multiple interaction among variables resulting in time lags with ET variations and thus these two variables were not included in the linear model. Soil water content, the fraction of photosynthetic active radiation and precipitation explained 86% of the ET monthly variations. The high volumetric water content and the small seasonal variations at 200-cm depth were probably the result of little water uptake from deeper soil horizons by roots with low hydraulic conductivity. Copyright © 2016 John Wiley & Sons, Ltd.

Total and marketable fruit yield of strawberry plants grown under different levels of nitrogen fertility and inoculated with azospirillum brasilense REC3; Rendimiento frutal total y comercial de plantas de frutillas cultivadas bajo diferentes niveles de fertilidad nitrogenada e inoculadas con Azospirillum brasilense REC3 Lovaisa, Nadia Carolina; Guerrero Molina, María Fernanda; Delaporte Quintana, Paola Adriana Georgina; Salazar, Sergio Miguel The aim of this work was to evaluate the agronomic response of strawberry plants (Fragaria ananassa Duch.)inoculated with Azospirillum brasilense as a biotechnological alternative to reduce or complement the plant nitrogen-fertilization under field conditions. The field trial was carried out in the province of Tucumán, Argentina, inoculating or not strawberry plants (cv. 'Camino Real') with A. brasilense REC3 and applying or not nitrogenfertilization. Treatments consisted in plants cultivated under different nitrogen fertilization (0%, 50%, 100%) with or without bacterial inoculation. The variables assessed were: SPAD relative values, total and marketable fruit yield, and growth index. As a result, it was observed that A. brasilense REC3 contributed positively to the nitrogen nutrition of strawberry plants growing at field conditions, expressed in the values of the variables assessed.

New theropod fauna from the Upper Cretaceous (Huincul Formation) of Northwestern Patagonia, Argentina Motta, Matias Javier; Aranciaga Rolando, Alexis Mauro; Rozadilla, Sebastian; Agnolin, Federico; Chimento, Nicolás Roberto; Brissón Egli, Federico; Novas, Fernando Emilio The present contribution describes theropod remains coming from the Huincul Formation (Neuquén Group; Cenomanian-Turonian; Upper Cretaceous) at a single locality located in northwestern Río Negro province, Patagonia, Argentina. This theropod association is composed of abelisauroids, two different-sized carcharodontosaurid allosauroids, a coelurosaur of uncertain relationships, a megaraptoran tyrannosauroid, and a possible unenlagiid paravian. Two new theropod genera and species are here described. The new carcharodontosaurid is based on an isolated postorbital bone bearing a unique prominence above the orbital brow. The new megaraptoran of uncertain affinities is described on the basis of a partially articulated tail and sacral vertebra. A new taxon is characterized by having notably elongate and highly pneumatic sacral and caudal vertebrae. It shows a large number of similarities with the African taxa Deltadromeus and Baharisaurus. These genera probably constitute a still poorly known clade of megaraptoran tyrannosauroids different from the Megaraptoridae. These findings support that Patagonia is a key place for understanding theropod evolution in Gondwana.

Percepción del verde urbano en parques de la ciudad de Buenos Aires; Urban green perception in Buenos Aires parks Perelman, Patricia Eleonora; Marconi, Patricia Laura El presente trabajo estudia, evalúa y analiza la percepción del verde urbano de la ciudad de Buenos Aires. La metodología empleada fue una encuesta de población en cuatro parques (Saavedra, Avellaneda, Centenario y Bastidas) representativa de la localidad en estudio (25% del área verde de la ciudad aprox.), dividida en cuatro partes: preguntas cerradas de elección múltiple para obtener los datos demográficos y sociales de los encuestados; preguntas generales (3) sobre la distancia y asiduidad de las visitas; y preguntas abiertas (5) donde los encuestados refirieron al lugar y motivo de la visita. Por último, se realizó una encuesta cerrada donde cada encuestado debió elegir 3 atributos que definieran al parque de una lista de 20. Los encuestados seleccionaron atributos que estaban en contraposición con el paisaje urbano. El análisis de los 4 parques en su conjunto permite identificar los 6 atributos más mencionados: tranquilidad, armonía, belleza, naturaleza, sonidos de la naturaleza, y verde. En general, las personas parecen buscar un bienestar personal, un lugar donde sentirse serenos y protegidos entre la vegetación. Los resultados hallados permiten concluir que si bien las percepciones son subjetivas, los factores que definen el paisaje son comunes.; This paper explores, evaluates and analyzes the perception of Buenos Aires urban green area. The methodology used was a population survey including four parks (Saavedra, Avellaneda, Centenario and Bastidas) representative of the locality under study (25% of the green area of the city), divided into four sets: multiple choice closed questions for the social and demographic data; general questions (3) on the distance and frequency of the visits; and open questions (5) where the respondents referred to the place and purpose of the visit; finally, a closed questionaire where each respondent had to choose three attributes that define the park from a total of 20 attributes. The subjects selected attributes for place identity that were opposed to urban landscape. The analysis of the 4 parks as a whole identifies 6 of the most frequently mentioned attributes: peace, harmony, beauty, nature, nature sounds, and green. In general, people seem to seek personal well-being, a place to feel calm and protected in vegetation. The obtained results suggest that although perceptions are subjective, landscape features are common.

Optimizing Product Launches in the Presence of Strategic Consumers Lobel, Ilan; Patel, Jigar; Vulcano, Gustavo; Zhang, Jiawei A technology firm launches newer generations of a given product over time. At any moment, the firm decides whether to release a new version of the product that captures the current technology level at the expense of a fixed launch cost. Consumers are forward-looking and purchase newer models only when it maximizes their own future discounted surpluses. We start by assuming that consumers have a common valuation for the product and consider two product launch settings. In the first setting, the firm does not announce future release technologies and the equilibrium of the game is to release new versions cyclically with a constant level of technology improvement that is optimal for the firm. In the second setting, the firm is able to precommit to a schedule of technology releases and the optimal policy generally consists of alternating minor and major technology launch cycles. We verify that the difference in profits between the commitment and no-commitment scenarios can be significant, varying from 4% to 12%. Finally, we generalize our model to allow for multiple customer classes with different valuations for the product, demonstrating how to compute equilibria in this case and numerically deriving insights for different market compositions.

Empleo del análisis multivariado en la evaluación de factores no genéticos de cabras Criollas; Use of multivariate analysis in the non-genetic factors assessment of Creole goats David, R. N.; Abdala, G. C.; Abdala, María Eugenia; Lescano, J. A. El peso al nacimiento en caprinos es un factor que siempre se pondera en los esquemas productivos por estar positivamente correlacionado con la tasa de crecimiento, con el tamaño del adulto, con el tiempo que tardan las crías en alcanzar peso de faena y con el tipo de alimentación que reciben. El peso al nacimiento varía en las distintas razas por ser determinado genéticamente. Hay productores que llegan a cambiar la raza de cabra buscando mejores pesos al nacimiento y desarrollos más precoces. Existen, sin embargo, factores no genéticos, que influyen en el peso al nacimiento y el desarrollo inicial que pueden llevar a confundir los resultados cuando se comparan diferentes razas buscando la producción de cabritos de mejores pesos al nacimiento y desarrollos más precoces. Sexo y número de camada son dos factores no genéticos relevantes en la determinación del peso al nacimiento y ya han sido demostrados en otras razas. En cabras Criollas, además de estos, se detecta que edad de la madre, número de parto de la madre, y mes de nacimiento también influyen. Se realizó un estudio de la influencia de todas estas variables en el peso al nacimiento y desarrollo inicial en un rebaño caprino de la Universidad Nacional de Santiago del Estero (UNSE), en el que se pesaron crías al nacimiento y en desarrollo inicial en cinco pariciones sucesivas. Se aplicó un análisis conjunto de todas las variables o multivariado, empleándose el método de componentes principales ACP, el cual detectó relaciones muy estrechas entre las variables en los tres ejes principales: 1) edad de la madre con número de parto, 2) peso con el tamaño de la camada y 3) otras relaciones, aunque débiles entre sexo y tamaño de camada. El ACP sirvió para sintetizar la información y mejorar la eficiencia en la interpretación de resultados, concentrando a los ejemplares en base a la influencia de las variables estudiadas con sus respectivos pesos al nacimiento, siendo los grupos 2 y 3 los de mayores pesos (3,18 kg y 3.4 kg respectivamente) y los bajos pesos para los grupos 1 y 4 (2,22 kg y 2,25 kg promedio, respectivamente).; In goats, birth weight is a factor that is always taken into account in the production systems since it correlates positively with growth rate, with adult size, with the time required for the offspring reach slaughter weight and with the type of food they receive. Birth weight varies in different races to be genetically determined. There are breeders who change the race of goat focusing on the better birth weight and more early development. However, there are non-genetic factors that influence on the birth weight and early development that can lead to confusing results when comparing different races to looking offspring production of better birth weight and early development. Sex and number of litter are two non genetic factors relevant in determining birth weight, that in addition already it was demonstrated in other races. In Creole goats in addition to these, we found that age of mother, calving number of the mother, and birth month also have influence. A study of the influence of these variables on birth weight and initial development in a goat herd was conducted at the Na-tional University of Santiago del Estero. In this study the offspring were weighed at birth and during early developmental conducted in five successive calving. A pooled analysis of all variables or multivariate analyzes were applied, using the method of principal component ACP, which detect very close relations between the variables in the three major axis: 1) age of mother with calving number, 2) weight with the litter size and 3) other relationships, though weak between sex and litter size. This method, ACP, helped to summarize information and improving efficiency in the interpretation of results, bringing together animals based on the influence of the variables studied and their birth weight. Thus the groups 2 and 3 they presented the higher weights (3.18 kg and 3.4 kg respectively), and groups 1 and 4, lower weights (2.22 kg and 2.25 kg average respectively).

Valve morphology of Didymosphenia geminata (Bacillariophyceae) in Chubut province, Argentina; Morfología valvar de Didymosphenia geminata (Bacillariophyceae) en la provincia de Chubut, Argentina Uyua, Noelia Mariel; Santinelli, Norma Herminia; Sastre, Alicia Viviana; Sala, Silvia Estela Recientemente se verificó que Didymosphenia forma proliferaciones masivas en Patagonia. En Argentina se ha esparcido a cinco provincias en un corto tiempo. En este trabajo, analizamos datos morfológicos y morfométricos de especímenes recolectados en la provincia del Chubut, Argentina y los comparamos con otras especies de este género de diferentes regiones del mundo. El material de estudio fue recolectado en dos cuencas durante 2010-2012. Las muestras, analizadas con MO y MEB, mostraron variación inter e intra-poblacional en las características morfométricas y en algunas estructuras valvares, como espinas. La morfología del material estudiado corresponde a la de D. geminata ssp geminata Metzeltin & Lange-Bertalot. Nuestros materiales también se asemejan a las especies: D. clavaherculis, D. clavamagna, D. coronata y D. laticollis. Los materiales de Chubut pueden ser fácilmente confundidos con algunos ejemplares mencionados en la literatura como D. clavaherculis, pero difieren claramente del material tipo de esa especie. Por otro lado, la morfología de los materiales estudiados coincide con los hallados en Chile. Aunque recientemente se publicó una extensa revisión morfológica del género Didymosphenia, todavía hay dudas en torno al grupo de taxones estrechamente relacionados con D. geminata. Actualmente se están realizando análisis moleculares que ayudarían a establecer los límites específicos.; Didymosphenia was recently found in Patagonia forming massive proliferations. In Argentina the species scattered in a short time to five provinces. Here, we analyse morphologic and morphometric data of specimens collected at Chubut Province, Argentina, and we compare them with other species of this genus reported from different regions of the world. Materials were collected in two basins during 2010- 2012. Samples analyzed with LM and SEM showed inter and intrapopulation variation in morphometric characteristics and in some valve structures such as spines. The studied material corresponds in valve outline and morphology to D. geminata ssp geminata Metzeltin & Lange-Bertalot. Our materials also resemble a group of species: D. clavaherculis, D. clavamagna, D. coronata and D. laticollis. The studied material can be easily confused to some specimens mentioned in the literature as D. clavaherculis but they clearly differ from the type material of the species. On the other hand, fine morphology of the studied materials coincides with materials from Chile. Although morphological revision of the genus recently published allowed separating many species, there are still doubts about specific limits of taxa closely related to D. geminata. Molecular analysis should be performed to clarify these issues.

El clero regular y el gobierno diocesano en el obispado de Córdoba del Tucumán en la tardocolonia: Aproximación historiográfica a un vínculo difuso; Regular clergy and diocesan government at the diocese of cordoba del tucuman in the late colonial period: a historiographical approach to a vague bond Mazzoni, María Laura La administración eclesiástica diocesana y las distintas órdenes regulares que se instalaron en el territorio de la gobernación del Tucumán han sido abordados, en la mayoría de los casos, como estamentos absolutamente diferentes y distanciados uno del otro. Las escasas vías de contacto entre ambos se constituyeron sobre la base del conflicto. En el caso del obispado de Tucumán, el extrañamiento de la Compañía de Jesús y el traspaso de la administración de la universidad a manos de la orden seráfica han sido de los pocos canales de encuentro que atraviesan ambas esferas en la historiografía. Nuestro trabajo propone repasar los estudios históricos, para el caso de la diócesis cordobesa, sobre las órdenes regulares con el objetivo de detectar los cruces entre la administración diocesana y el clero regular. Marcar los posibles vínculos en el nivel institucional, pero también relacional, constituirá un segundo propósito a lo largo de esta aproximación.; The diocesan government and the distinct regular orders that settled in the territory of Tucumán have been approached mostly as quite different and away from each other. The scarce links between these institutions were based on conflict. In Córdoba del Tucumán, the expulsion of Jesuit order, and the transfer of the university management into the hands of the Franciscan order have been some of the few aspects where historiography has found some links. This article aims to review the historical studies about regular orders focusing on the bonds between diocesan government and regular clergy. Another objective of this paper is to highlight possible interactions and relationships of those institutions.

Nacionalsocialistas anti-hitleristas y cuestión judía: Los casos de Die Schwarze Front y Frei-Deutschland Bewegung en la Argentina; Anti-hitlerite national socialists and jewish question: The cases of die schwarze front and frei-deutschland bewegung in Argentina Friedmann, Germán Claus Following Hitler's rise to power in Germany, National Socialism started a process of Gleichschaltung (uniformity) throughout diverse institutions belonging to the German community in Argentina. Though successful, it did not encompass them entirely. Associations that gathered Germanspeaking members of diverse origins sharing a common opposition to the Third Reich sprung to life during the 1930's and 1940's. Among the motley group of anti-Hitlerite militants, were two groups directed from his exile by Otto Strasser, who during the 1920's had been one of the main figures of the Nationalsozialistische Deutsche Arbeiterpartei (National socialist German worker's party). Local Strasser followers presented their points of view regarding the escalation of anti-Semitism in Europe, made their thoughts on the relationship between Jews and Germany known, and kept in touch with the German-speaking Jewish émigrés.

Espacios para la memoria: Narrativas sobre la violencia Zarankin, Andrés; Salerno, Melisa Anabella En este trabajo centramos nuestro interés en diversos “espacios para la memoria” surgidos como recordatorios de un pasado violento. Entre ellos consideramos los sitios donde se da cuenta de la antigua división de Alemania (representados por el tratamiento brindado a los restos del Muro de Berlín); los espacios para la memoria del bombardeo atómico sobre Japón (incluyendo los museos que refieren al tema en Hiroshima y Estados Unidos); los sitios para la reflexión sobre la última dictadura militar en Argentina (contando los ex centros clandestinos de detención, parques, plazoletas, monolitos, etc. en Buenos Aires). Nuestro objetivo reside en discutir la diversidad contenida en los proyectos ensayados. Para ello proponemos abordar la materialidad de los espacios construidos, las ideas y sensaciones a los que apelan, y las narrativas que pretenden construir. El enfoque permite comprender las tensiones que comúnmente involucra la construcción de la memoria en el presente.; Neste artigo concentramos o nosso interesse em vários "espaço para a memória" surgidos como recordações de um passado violento. Dentre eles, podemos considerar os sítios onde ser percebe a antiga divisão da Alemanha (representado pelo tratamento dado aos restos do Muro de Berlim); espaços de memória do bombardeio atômico sobre o Japão (incluindo o endereço dos museus sobre esse tema em Hiroshima e nos Estados Unidos); sítios para refletir sobre a última ditadura militar na Argentina (contando os antigos centros de detenção clandestinos, parques, praças, monolitos, etc, em Buenos Aires). Nosso objetivo é discutir a diversidade contida nos projetos analisados. Propomo-nos abordar a relevância dos espaços construídos, idéias e sentimentos e as narrativas que buscam construir. Uma abordagem que permite a compreensão das tensões que comumente envolvem a construção da memória no presente.

Application of quantitative structure-property relationship analysis to estimate the vapor pressure of pesticides Goodarzi, Mohammad; Coelho, Leandro dos Santos; Honarparvar, Bahareh; Ortiz, Erlinda del Valle; Duchowicz, Pablo Román The application of molecular descriptors in describing Quantitative Structure Property Relationships (QSPR) for the estimation of vapor pressure (VP) of pesticides is of ongoing interest. In this study, QSPR models were developed using multiple linear regression (MLR) methods to predict the vapor pressure values of 162 pesticides. Several feature selection methods, namely the replacement method (RM), genetic algorithms (GA), stepwise regression (SR) and forward selection (FS), were used to select the most relevant molecular descriptors from a pool of variables. The optimum subset of molecular descriptors was used to build a QSPR model to estimate the vapor pressures of the selected pesticides. The Replacement Method improved the predictive ability of vapor pressures and was more reliable for the feature selection of these selected pesticides. The results provided satisfactory MLR models that had a satisfactory predictive ability, and will be important for predicting vapor pressure values for compounds with unknown values. This study may open new opportunities for designing and developing new pesticide.

La industria argentina de harina de trigo en el cambio de siglo: Límites y alcances, 1880-1914; Flour milling industry in Argentina at the turn of the century: Limitations and scopes, 1880-1914 Martiren, Juan Luis; Rayes, Agustina La expansión agraria producida en la región pampeana entre el último cuarto del siglo XIX y las dos primeras décadas del XX, convirtió a este espacio en uno de los mayores nichos productores de cereales del mundo. Como corolario, este proceso permitió la emergencia de una industria harinera que en pocos años acaparó los mercados nacionales y se posicionó fuertemente en las plazas de abasto brasileñas. No obstante, para ingresar a este mercado las harinas argentinas debieron enfrentar constantemente fuertes restricciones arancelarias, lo cual, según la bibliografía especializada, supuso un importante freno a la expansión de esta industria. En este trabajo proponemos revisitar esa imagen, al presentar evidencia estadística seriada sobre índices de producción, precios y comercio exterior del producto, con el fin de mostrar, además de la evolución creciente de la industria, que el peso de las exportaciones ha sido sobrevalorado en la bibliografía.; The agrarian expansión in the Pampean region between the last quarter of the XIXth century and the first two decades of the XXth transformed this area in one of the largest world’s cereal production cores. As a result, this process allowed the emergence of a flour milling industry that readily garnered national and Brazilian markets. However, to enter into them, Argentine flour faced tariff restrictions, wich, according to the literature, was a major obstacle to the expantion of this industry. In this paper we propose to revisit that image, presenting statistical evidence on serial production rates, prices and foreign trade of the product, in order to show the the weight of exports has been overrated in this literature.

Second-order magnetic critical points at finite magnetic fields: Revisiting Arrott plots Bustingorry, Sebastián; Pomiro, Fernando; Aurelio, Gabriela; Curiale, Carlos Javier The so-called Arrott plot, which consists in plotting H/M against M2, with H the applied magnetic field and M the magnetization, is used to extract valuable information in second-order magnetic phase transitions. Besides, it is widely accepted that a negative slope in the Arrott plot is indicative of a first-order magnetic transition. This is known as the Banerjee criterion. In consequence, the zero-field transition temperature T∗ is reported as the characteristic first-order transition temperature. By carefully analyzing the mean-field Landau model used for studying first-order magnetic transitions, we show in this work that T∗ corresponds in fact to a triple point where three first-order lines meet. More importantly, this analysis reveals the existence of two symmetricalsecond-order critical points at finite magnetic field (Tc,±Hc). We then show that a modified Arrott plot can be used to obtain information about these second-order critical points. To support this idea we analyze experimentaldata on La2/3Ca1/3MnO3 and discuss an estimate for the location of the triple point and the second-order critical points

Programación de la producción a corto plazo y de tareas de mantenimiento preventivo en ambientes Job Shop Flexibles Sirolla, Mauricio Daniel; Novas, Juan Matias; Henning, Gabriela Patricia Se aborda el problema de scheduling predictivo en plantas industriales de tipo Job Shop Flexible para el que se ha desarrollado un modelo basado en programación con restricciones (Constraint Programming, CP) que permite obtener una agenda eficiente para un conjunto de partes o Jobs conocido de antemano. El modelo considera las características de este tipo de ambiente industrial: recetas de manufactura específicas para cada Job, unidades multipropósito y disímiles para llevar a cabo cada operación, tiempos de alistamiento de equipos y de disponibilidad inicial de las máquinas, etc. Además, la formulación considera la necesidad de ejecutar tareas de mantenimiento preventivo en cada equipo. El modelo se ha verificado y validado utilizando diferentes ejemplos de tamaño medio disponibles en la bibliografía, hallándose soluciones de muy buena calidad en bajos tiempos de cómputo, lo que permite inferir las bondades del modelo.

Epipelon dynamics in a shallow lake through a turbid-and a clear-water regime Cano, Maria Gabriela; Casco, Maria Adela; Claps, Maria Cristina In Pampean lakes, very little information is available on epipelon structure and dynamics or the effect of environmental variables on those parameters. We anticipate that light may have the greatest influence on this community and that the nutrient concentration and substrate instability may exert secondary effects. Our objective was to analyze variations in descriptive parameters and in the algal species composition of the epipelon in the Pampean Lake Lacombe over space and time to establish the most influential environmental forces (light climate, wave action, nutrients). Sediment was collected from the benthos with a 3.5-cm-diameter corer in a year-round sampling every month at four sites in the lake that differed from each other in depth, distance from the shore, and the presence of emergent and submerged macrophytes. Although Lacombe is a shallow lake, differences occurred in community descriptive variables and in the epipelon composition (especially diatoms) over space and time. In particular, differences between the site nearest to the shore and the rest of the sites were found with respect to environmental variables (sediment-particle size, total phosphorus, organic matter content, light climate), epipelon descriptive parameters (abundance, chlorophyll a and Margalef’s index) and epipelon composition (especially specific biovolume and diatom-size classes). The epipelon also reflected, though slightly, the change from the turbid- to clear-water states in the lake. Sediment erosion or deposition was evidenced by differences in the sediment-particle composition and the predominant particle-size classes at each site. Statistical analyses indicated linear correlations between the epipelon parameters and variables related to the light climate in the water column. Conductivity and sediment total phosphorus and density were also correlated, but to a lesser extent, with epipelon composition. The epipelon variations in Lacombe Lake would exemplify the reference communities developed during clear or turbid regimes in Pampean shallow lakes. We found evidence for the influence of light climate and wave action (through instability of the substrate) on this community, but the effect of nutrients was negligible. We emphasize that the close relationships maintained by the epipelon with other communities such as the phytoplankton and the epiphyton may superimpose the patterns of variation to those communities onto the epipelon dynamics.

An index to evaluate the fluvial habitat degradation in lowland urbanstreams Cochero, Joaquin; Cortelezzi, Agustina; Tarda, Alan Santiago; Gomez, Nora The objective of the present article is to propose an index that allows the assessment of the fluvial habitat quality in lowland streams that run through urbanized areas, by the use of metrics related to the quality of the watercourse, the river banks, the riparian zone and the fluvial geomorphology. The metrics retained in the index (USHI, Urban Stream Habitat Index) include the cover percentage and quality of the aquatic vegetation; the main features of the river banks; the presence of exotic trees, of litter, of permanent structures (such as buildings) in the riparian zone and other major geomorphological alterations, such as dredging or channelization. The index is related to physical-chemical parameters that are linked to water quality, the imperviousness of the watershed and to other biotic descriptors, particularly the macroinvertebrate and diatom assemblages. The values of the index for the sites in the studied area revealed that 41.2% have a bad or very bad habitat quality, 27.8% a moderate habitat quality, while 31% have a good or very good habitat quality. The main issue detected in the studied sites involved the dredging or partial channelization of the reaches. Unlike other indices that evaluate the quality of the physical habitat through the use of the diatoms or macroinvertebrate communities, the USHI can be interpreted as a measure of the overall quality of the habitat, and uses indicators that do not require the identification of taxa, making it more accessible to non-specialists. Therefore it provides with a tool to evaluate the fluvial habitat quality of lowland streams that can be easily applied, particularly by professionals that take part in the management and decision making process regarding urbanized watersheds.

Family Ceratopogonidae Spinelli, Gustavo Ricardo; Wolff, Marta Two hundred and thirty five species of Ceratopogonids arranged in 28 genera are listed for Colombia, mostly Culicoides (112 species) and Forcipomyia (50 species). For each listed species, information on type locality, type category and sex, location of type material, species distribution, localities for Colombia and main references, is provided. Localities are not
specified for 17 species in which the literature searching was negative. Forcipomyia squamitibia Lutz and Bezzia clavipennis are excluded from the list.

Altered soil carbon dynamics under different land-use regimes in subtropical seasonally-dry forests of central Argentina Conti, Georgina; Kowaljow, Esteban; Baptist, Florence; Rumpel, C.; Cuchietti, Anibal; Pérez Harguindeguy, Natalia; Díaz, Sandra Myrna Background and aims Subtropical seasonally dry forestsfrom South America are now experiencing one ofthe highest rates of forest-cover change globally. Thesechanges may affect the dynamics of soil organic carbon(SOC) including long-term stabilization processes, withprofound consequences for the fertility and carbon storageof these ecosystems.Methods In order to explore the effect of different landuseregimes on SOC dynamics, we determined theamount and quality of plant litter, the amount and quality(lignin and carbohydrate content) of SOC, and thesoil basal respiration rates across seasonally dry Chacoforests of Argentina.Results Changes in land-use regimes significantly reducedthe amount of litter but not its quality. As aconsequence, the SOC content was also reduced togetherwith SOC quality. Unexpectedly, we found a higherCO2 release per SOC unit in soils with lower amountand quality of SOC.Conclusions The results presented here show a cleareffect of different land-use regimes on SOC dynamicsthrough a reduction in the amount and quality of SOC.Additionally, we found that potential microbial activityis somehow disconnected from substrate quantity andquality, suggesting that the molecular structure of SOCis not significantly affecting long-term soil stabilizationprocesses across these seasonally-dry ecosystems.